1.1 Heer Office Legal Authorities
...substances listed in various federal environmental protection laws such as the Clean Water Act, CERCLA, the Solid Waste Disposal Act, the Clean Air Act, and the Toxic Substances Control ...
 

1.4 Environmental Health Administration Divisions
... is responsible for implementing and maintaining statewide programs for controlling air, water and wastewater pollution, assuring safe drinking water, and for the proper management of solid ...
 
...and wastewater pollution, assuring safe drinking water, and for the proper management of solid and hazardous ...
 
...pollution, assuring safe drinking water, and for the proper management of solid and hazardous waste. The EMD is organized into five ...
 
... within the branch. " target="_blank">Safe Drinking Water Branch (SDWB)-administers federal and state safe drinking water regulations for public ...
 
...Branch (SDWB)-administers federal and state safe drinking water regulations for public water systems in the state to assure water served by these ...
 
... regulations for public water systems in the state to assure water served by these systems meets state and federal standards. ...
 
...systems in the state to assure water served by these systems meets state and federal standards. " target="_blank">Clean ...
 
... systems meets state and federal standards. " target="_blank">Clean Water Branch (CWB)-administers and enforces federal and state water pollution control laws and ...
 
...Branch (CWB)-administers and enforces federal and state water pollution control laws and regulations. Services include permitting of point sources, compliance ...
 
...compliance monitoring, inspections, investigations of complaints, and ambient water quality monitoring. " target="_blank">Clean Air Branch (CAB)-responsible ...
 
...and state air pollution control laws and regulations. " target="_blank">Wastewater Branch (WWB)-implements construction of County wastewater facilities and is ...
 
... Branch (WWB)-implements construction of County wastewater facilities and is involved in related regulatory and financing issues. ...
 
...use reviews and helps get new programs underway. They are also involved in coordinating watershed management projects and the polluted runoff control program. 1.4.5 ...
 

2.1 State Contingency Plan
...of a variety of waste, accidentally spilled substances, abandoned materials, soil, groundwater, surface water, air, and leaking underground tanks may be addressed through the Hawai`i ...
 
...surface water, air, and leaking underground tanks may be addressed through the Hawai`i SCP. ...
 
... In some cases, such as during emergency responses and responses to contaminated surface water, drinking water, outdoor air, soil vapor, or leaking underground tanks, the HEER Office may ...
 
...drinking water, outdoor air, soil vapor, or leaking underground tanks, the HEER Office may refer cases to ...
 

2.3 Emergency Response
...criteria for notification: Any amount of oil causing a sheen to appear on surface water or any navigable water of the State (sheens resulting from discharge of oil from a properly ...
 
...or any navigable water of the State (sheens resulting from discharge of oil from a properly functioning ...
 
...functioning vessel engine are exempt) Any free product that appears on groundwater Any amount of oil greater than 25 gallons released to the environment Any amount of ...
 

2.4 Environmental Cleanups
...complex environmental cleanups involving multiple contaminants and both soil and groundwater contamination can involve years of effort before the site is adequately cleaned up and closed. ...
 
...are discovered and removed during an emergency response, but some sub-soil or groundwater contamination still remains Groundwater contamination discovered in a non-drinking ...
 
...contamination still remains Groundwater contamination discovered in a non-drinking groundwater aquifer located below a former gasoline ...
 
...contamination discovered in a non-drinking groundwater aquifer located below a former gasoline service station A Phase II Environmental ...
 
...Site Assessment required by a financial institution reveals soil or groundwater contaminated with a hazardous substance above HEER Office Environmental Action Levels ...
 
...have typically aged, weathered, absorbed, or dispersed into the soil, or diluted in groundwater to the point that the contamination present does not pose a significant short-term hazard. ...
 
...staining or sampling data indicated the potential for remaining subsurface or groundwater contamination An overview of the discovery, assessment, and cleanup steps for non-emergency ...
 
...releases are usually identified when environmental samples (typically soil and/or groundwater) are collected at a site, and sample analysis shows Tier 1 EAL exceedances. These exceedances ...
 
...substance releases, including actual or probable releases to: Groundwater that is a drinking water supply Surface water that is a drinking water supply Groundwater ...
 
...that is a drinking water supply Surface water that is a drinking water supply Groundwater or surface water ...
 
...supply Surface water that is a drinking water supply Groundwater or surface water that is not a drinking water supply ...
 
...that is a drinking water supply Groundwater or surface water that is not a drinking water supply Air that poses ...
 
...supply Groundwater or surface water that is not a drinking water supply Air that poses a threat to public health ...
 
...or surface water that is not a drinking water supply Air that poses a threat to public health Soil ...
 
...that is not a drinking water supply Air that poses a threat to public health Soil that may pose a direct exposure ...
 
...substances, such as leaking containers or impoundments Soil, soil gas, indoor air, groundwater, or surface water that has contamination levels exceeding HDOH Tier 1 EALs Adverse ...
 
...or surface water that has contamination levels exceeding HDOH Tier 1 EALs Adverse impacts to natural ...
 
...The goal of a site assessment is to identify and remediate contaminated soil and groundwater that poses unacceptable environmental hazards, either under current site conditions or ...
 
...The investigation is carried out by the collection and analysis of samples of soil, groundwater, soil gas, surface water, sediment, air and/or other media as needed (see Sections 4 through ...
 
...soil gas, surface water, sediment, air and/or other media as needed (see Sections 4 through 11). The HDOH " ...
 
...absence of potential hazards may simply be identified and the contaminated soil or groundwater quickly remediated without further assessment. In cases where remedial costs could be significant ...
 
...13 and Evaluation of Environmental Hazards at Sites with Contaminated Soil and Groundwater, ">HDOH, 2008). This will help make the final EHE more site-specific and ensure that ...
 
...is causing immediate environmental hazards (e.g., free product discharging into a surface water body or vapor intrusion into a building) and prepare an Environmental Hazard Management Plan ...
 
... Cause of release or threat Site history General site geology, hydrology, groundwater status, adjacent land uses Distance to surface water bodies Situation preceding decision ...
 
...status, adjacent land uses Distance to surface water bodies Situation preceding decision to conduct removal Efforts by Dept. to obtain ...
 

2.5 Site Closure
...address contamination that may remain at the site (e.g., in the subsurface soil or groundwater). In these instances, the NFA letter will indicate that the emergency response has been appropriately ...
 
...Office guidance for Long-Term Management of Petroleum-Contaminated Soil and Groundwater, responsible parties may request the HEER Office to issue a determination that "No Further ...
 

Contents
... 3-27. Stormwater drainage vault designated as a DU for testing of sediment runoff from a contaminated ...
 
... DU Designated for Characterization of Sediment at the Mouth of a Wastewater Pond Outfall   ...
 

3.0 Site Investigation Design And Implementation
... as needed. For example, detection of high levels of tetrachloroethylene in groundwater during a site investigation could suggest vapor intrusion as a potential environmental ...
 
...could suggest vapor intrusion as a potential environmental hazard (e.g., groundwater action level for vapor intrusion exceeded). This could trigger the collection of soil gas samples ...
 

3.1 Site Investigation Scoping
...up on Phase I findings through the collection, analysis and evaluation of soil, groundwater, soil gas or other types of environmental samples (e.g., lead and asbestos testing of building ...
 
... maps and area-wide descriptions of geology, soil types, topography, and groundwater conditions); Historical use sources (e.g., aerial photographs, ...
 

3.2 Systematic Planning Of Site Investigation
...progression of environmental investigations at sites with contaminated soil and groundwater. Preparing DQOs prior to the initiation of field activities should ...
 
... Do preliminary data indicate the presence of contaminants in soil, groundwater or other environmental media greater than the HDOH Tier 1 Environmental Action Levels ...
 
...hazards at a site (e.g., direct exposure, vapor intrusion, leaching to groundwater, etc.). The site investigation must be designed to meet this objective, as well as to provide ...
 
...risk to residents? Is the size of the benzene plume in groundwater increasing, stable or shrinking? Does the contamination at the site extend ...
 
...of debris or fill material, location of utilities, depth to and use of groundwater, location and types of other manmade structures, etc. Identify nearby water supply wells, ...
 
...location and types of other manmade structures, etc. Identify nearby water supply wells, bodies of surface water and other potentially sensitive ecological habitats ...
 
...supply wells, bodies of surface water and other potentially sensitive ecological habitats that could be threatened by the ...
 
... in Evaluation of Environmental Hazards at Sites with Contaminated Soil and Groundwater (HDOH, 2011). Step 3—Identify Data Needs ...
 
...What types of media should be collected and analyzed (e.g., soil, soil gas, groundwater, surface water, etc.) based on areas and types of potential contamination? ...
 
...surface water, etc.) based on areas and types of potential contamination? For groundwater, ...
 
...etc.) based on areas and types of potential contamination? For groundwater, how often will sampling need to be repeated, and how will samples for specific contaminants ...
 
... the targeted, decision unit. In general, contaminants in soil, water, soil gas or indoor air at concentrations below the Tier 1 EALs do not pose a significant ...
 
...of soil gas samples. Concurrent collection of groundwater data should be considered at sites where soils are grossly contaminated with highly mobile ...
 
...the type of contaminants present could otherwise pose significant leaching and groundwater contamination hazards (e.g., herbicides, such as atrazine). In other cases, additional ...
 
... Collection of soil gas data at sites where initial soil and/or groundwater data indicate potential vapor intrusion hazards. Analysis of soil samples that exceed ...
 
...area and more specifically the volume of the targeted media (e.g., soil, sediment or water) that would be collected and analyzed as a single unit if possible. This is rarely if ...
 
...target contaminant is highly leachable from the soil and could pose a threat to groundwater resources or is highly volatile and could pose potential vapor intrusion hazards for buildings ...
 
...highly volatile and could pose potential vapor intrusion hazards for buildings (e.g., water-soluble pesticides, solvents, light-end petroleum fuels, etc.). For relatively non-mobile ...
 
...driving environmental hazard is often direct exposure, rather than leaching and groundwater protection (e.g., arsenic, lead, PCBs, polychlorinated dibenzodioxins and polychlorinated ...
 
... Section 5. Issues to consider in developing the SAP for soil, groundwater, soil gas and other targeted media include: How can sample collection ...
 
... what is the minimal well size needed to collect the necessary amount of groundwater for sample analyses, given the site geology (e.g., micro-wells may not allow the ...
 
...collection methods are discussed in Sections 4 and 5. The collection of groundwater samples is discussed in Section 6. Soil gas and indoor air sampling is discussed ...
 
... on the samples to better evaluate contaminant mobility and the threat to groundwater. These possible outcomes should be identified in advance under Step 3 and contingencies ...
 
...staff at the anticipated or potential concentrations in soil, soil gas and groundwater? What physical site conditions could pose hazards to field staff and what ...
 
... A summary of common environmental hazards posed by contaminated soil and groundwater is provided in Figure 3-5. Site investigations and Environmental Hazard Evaluations ...
 
...to the mean concentration of a COPC in the target media (e.g., soil, air or water) over a specified area and volume of that media. The latter, referred to as the decision ...
 
...evaluate contaminant mobility (HDOH, 2007, 2011) and/or the collection of groundwater data (Section 6)? Do reported concentrations of COPCs in soil or groundwater ...
 
...(Section 6)? Do reported concentrations of COPCs in soil or groundwater data present potential vapor intrusion concerns, indicating the need for soil gas or ...
 
... excavation activities? Do high levels of contaminants in groundwater indicate potential impacts to nearby aquatic habitats, suggesting the need to collect ...
 
...to nearby aquatic habitats, suggesting the need to collect additional groundwater, sediment or surface water data? Do high levels of COPCs in soil and groundwater ...
 
...sediment or surface water data? Do high levels of COPCs in soil and groundwater pose a threat to ...
 
...data? Do high levels of COPCs in soil and groundwater pose a threat to offsite migration which could lead to contamination of adjacent properties? ...
 

3.3 Conceptual Site Models
...common environmental hazards associated with contaminated soil and groundwater as well as potential exposure pathways for human and ecological receptors. ...
 
...depiction of environmental hazards associated with contaminated soil and groundwater (see also Figure 3-5). Exposure pathways to human and ecological receptors are also indicated ...
 
...includes a summary of the known or suspected extent and magnitude of soil and groundwater contamination. In addition, site conditions such as land use, groundwater use, potential ...
 
...contamination. In addition, site conditions such as land use, groundwater use, potential onsite and offsite receptors, exposure or isolation of contaminated soil, ...
 
...by the COPC. Common environmental hazards associated with contaminated soil and groundwater (Figures 3-5 and 3-6) include: Contaminated Soil: ...
 
...vapors to building interiors; Leaching and contamination of groundwater resources; Impacts to terrestrial habitats (terrestrial ...
 
...odors, general resource degradation, etc.); Contaminated Groundwater: Contamination of drinking water resources (toxicity, taste ...
 
... Contamination of drinking water resources (toxicity, taste and odors); Emission of subsurface vapors to ...
 
...vapors to building interiors; Discharges of contaminated groundwater to surface water aquatic habitats (aquatic ecotoxicity or gross contamination conditions); ...
 
... to surface water aquatic habitats (aquatic ecotoxicity or gross contamination conditions); Gross contamination ...
 
... (e.g., uptake of contaminants in produce, runoff of contaminated soil into surface water bodies, etc.). A more detailed discussion of these and other potential environmental hazards ...
 
...Evaluation of Environmental Hazards at Sites with Contaminated Soil and Groundwater (HDOH, 2011). These environmental hazards form the basis of the ...
 
... CSMs or site scenarios are provided for in the Tier 1 EALs, depending on groundwater utility and location of a subject site with respect to nearby surface water bodies ...
 
... utility and location of a subject site with respect to nearby surface water bodies and aquatic habitats (Figure 3-7; HDOH, 2011): The default ...
 
...for preparation of an Environmental Hazard Evaluation (see Section 13). Only surface water bodies that are hydraulically connected to groundwater are considered to be potentially ...
 
... bodies that are hydraulically connected to groundwater are considered to be potentially threatened by contaminated groundwater. This could include ...
 
...are considered to be potentially threatened by contaminated groundwater. This could include streams, drainage ways, or even leaky storm sewers that lead to a surface ...
 
...include streams, drainage ways, or even leaky storm sewers that lead to a surface water body. Given their direct and potential rapid link to aquatic habitats, storm sewers in ...
 
...aquatic habitats, storm sewers in direct hydraulic connection with contaminated groundwater are considered to represent a "surface water body" for initial screening purposes. Measuring ...
 
...are considered to represent a "surface water body" for initial screening purposes. Measuring the piping invert in relation to the groundwater ...
 
... for initial screening purposes. Measuring the piping invert in relation to the groundwater table at high-high tides and the presence or absence of free product at the discharge ...
 
... point of a storm drain can help determine if it serves as a pathway to a surface water body. Data for a site are screened against Tier 1 EALs for the default ...
 
...Site Model used to develop Tier 1 EALs for sites that overlie a source of drinking water and are within 150m of a surface water body; assumes impacted soil exposed at surface. ...
 
...and are within 150m of a surface water body; assumes impacted soil exposed at surface. ...
 
...be significant, or at sites where long-term management of contaminated soil or groundwater will be required. A closer evaluation of current and future risks to human or ecological ...
 
... site boundaries; Area of contaminated soil is paved; Underlying groundwater is not a current or potential source of drinking water; Site is located ...
 
...is not a current or potential source of drinking water; Site is located more than 150m from the nearest surface water body. ...
 
... Site is located more than 150m from the nearest surface water body. A "Yes" in a cell under "Receptors" indicates that the noted ...
 
...that the pathway for leaching of contaminants from soil and contamination of groundwater is complete, because contaminated soil is in direct contact with groundwater, even though ...
 
...is complete, because contaminated soil is in direct contact with groundwater, even though the area is assumed to be capped with pavement. This is used to support the ...
 
...assumed to be capped with pavement. This is used to support the collection of groundwater data to more directly evaluate impacts and potential concerns. Removal of pavement could ...
 
...and potential concerns. Removal of pavement could also exacerbate leaching and groundwater contamination due to infiltrating rain or irrigation water. This could require the maintenance ...
 
...contamination due to infiltrating rain or irrigation water. This could require the maintenance of an impermeable cap over the contaminated soil under ...
 
...detailed CSM may be used to support a conclusion that contaminated soil and groundwater does not pose unacceptable environmental hazards under current site conditions. Depending ...
 
...of contaminated soil remain capped, that a health and safety plan and soil and groundwater management measures be developed prior to any subsurface construction activities at the ...
 
...activities at the site, and that the need for long-term monitoring of groundwater be further evaluated. Actions related to restricted-use site closure, and the preparation ...
 
...environmental hazards, including leaching and potential contamination of groundwater (refer to Figure 3-5; see also Section 13). As discussed in Sections 2, 3 ...
 
...with other relevant information): Additional soil, soil vapor or groundwater data; Location of existing monitoring wells and past ...
 
...based on decision unit and Multi Increment sample data); Groundwater contamination summary figures with areas above EALs highlighted; Soil ...
 
...figures with areas above EALs highlighted; Direction of groundwater flow, depth to groundwater; Cross sections that depict the site ...
 
...flow, depth to groundwater; Cross sections that depict the site stratigraphy as well as the lateral ...
 
...or preferential pathways (e.g., addition of underground piping), roads, surface water bodies, neighboring property operations and land uses, geographical features, etc.; ...
 

3.4 Selection Of Decision Units
...Evaluation of Environmental Hazards at Sites with Contaminated Soil and Groundwater (HDOH, 2011). 3.4.1 DECISION UNIT DESIGNATION ...
 
...be selected to characterize the area. DUs for different media (e.g. soil vs. groundwater vs. soil gas vs. indoor air) should in most cases be treated separately, even if they are ...
 
...environmental hazards, including leaching of contamination to subsurface groundwater resources, intrusion of vapors into overlying buildings and nuisance or even explosion ...
 
...or other chemicals that could migrate downwards and contaminate deeper soil or groundwater. A subsurface investigation may also be required to further delineate contamination documented ...
 
... to be contaminated by the tank release and soil at capillary fringe zone at the water table. Including a core interval across the capillary fringe is especially useful, since ...
 
...has the highest chance of catching the presence of contamination that has reached the water table (see Figure 3-14). Such core intervals might be considered "discrete" samples ...
 
...forthcoming. Sediment is defined as unconsolidated material that is currently under water (e.g., harbor bottom sediment) or otherwise associated with deposition in an aquatic environment ...
 
... Sediment geochemistry, Size distribution of sediment particles, Water flow rate and volume, Location of depositional areas, Local features (natural ...
 
... Stratification can affect the nature of contamination at the water-sediment interface, necessitating seasonal sampling and leading to significant and abrupt ...
 
...to be collected from the biotic zone (e.g., the 0 to 4-inch interval) at the sediment-water interface. Deeper samples might be necessary to delineate the vertical extent of contamination ...
 
...or urban areas, or aquatic areas impacted by long-term discharges of industrial waste water. If this is the case, replicate field samples could document adequate sample precision ...
 
...(e.g. explosives residues) can also pose potential leaching threats to groundwater that might be used to serve the redevelopment in the future. A default ...
 
...Evaluation of Environmental Hazards at Sites with Contaminated Soil and Groundwater (HDOH, 2011). When using a Decision Unit strategy, the entire area of a Decision Unit is ...
 

3.5 Example Decision Units
... Figure 3-27. Stormwater drainage vault designated as a DU for testing of sediment runoff from a ...
 
...a single sample might be feasible. Examples include small volumes of sediment in stormwater sumps being tested to assess contaminant runoff from a property (Figure 3-27). This ...
 
...approximately 1,000 ft2 to 2,000 ft2. These areas primarily pose leaching and groundwater impact hazards. Subsurface DU layers designated for the site are ...
 
...on the nature of the release and the objectives of the investigation. Example shallow water sediment DUs are presented in Figures 3-32 through 3-36. The examples are taken from actual ...
 
...3-32 depicts sediment DUs designated for a drainage canal that once carried waste water from a sugar mill. Testing of surface soil at discharge points suggested that sediment ...
 
...The next example illustrates a single sediment DU designated at the outfall of a wastewater pipe. A single DU is designated given the anticipated similarity of impacts within the ...
 
... Figure 3-33. DU Designated for Characterization of Sediment at the Mouth of a Wastewater Pond Outfall "Xs" indicate increment collection locations ...
 
...estuary suspected to have been impacted by historic arsenic-contaminated wastewater and runoff from past agricultural operations in the area. The pond is tidally influenced. ...
 
...agencies. Note that the use of dredge material from salty or brackish water bodies as fill material in upland areas is not recommended due to potential salinity problems. ...
 
...can also cause soil to harden and form clods when dry, impeding the uptake of water during rainfall or irrigation and again reducing plant growth. A SAR value greater than ...
 
...concerns associated with the reuse of dredge material include runoff of saline water during rain events, as well as leaching of salt and impacts to underlying groundwater. ...
 
...during rain events, as well as leaching of salt and impacts to underlying groundwater. (Note that while a high sodium content can inhibit leaching and runoff, this will also ...
 
...appropriate on a case-by-case basis, the general use of dredge material from saline water bodies for fill material is not recommended without prior review and approval by HDOH. ...
 

3.6 Sampling And Analysis Plans
... Section 4.3). See Section 6 for sample collection strategies for groundwater, and Section 13 for information and references regarding ecological risk evaluations. ...
 
...useful for a given site. Sampling method procedural guidance for soil and sediment, groundwater and surface water, and soil vapor and indoor air is presented in Sections 5, ...
 
... and surface water, and soil vapor and indoor air is presented in Sections 5, 6, and 7, respectively. ...
 
...of Decision Unit approaches is recommended for characterization of sediment and surface water as well as soil. 3.6.3 HEALTH AND SAFETY PLANS Hawai’i hazardous ...
 

3.8 Data Quality Assessment
... did not delineate the vertical or horizontal extent of contamination, or if groundwater was not encountered due to drilling refusal at a site where groundwater was believed ...
 
... was not encountered due to drilling refusal at a site where groundwater was believed to be impacted; then additional sampling would typically be required. ...
 

3.9 Site Investigation Reports
...HEER Office requires that the lateral and, as needed, vertical extent of soil and groundwater (and in some cases soil gas) contamination be clearly depicted on to-scale maps and cross sections ...
 

3.10 Environmental Hazard Evaluation
...Evaluation of Environmental Hazards at Sites with Contaminated Soil and Groundwater (HDOH, 2011). An overview of the document is provided in Section 13. As ...
 
...to identifying potential environmental hazards associated with contaminated soil or groundwater is a direct comparison of site data to the HDOH Tier 1 EALs (see Section 13). ...
 
... of a COPC exceeds the Tier 1 EAL in the subject media (e.g., soil, soil gas, or groundwater) then the specific environmental hazard(s) potentially posed by the chemical should be identified ...
 
...leaching hazards associated with a COPC suggests that batch testing and/or groundwater data may be needed. The identification of potential vapor intrusion concerns suggests that ...
 

4.0 Characterization Of Decision Units
... Ideally, the entire, targeted volume of soil or other targeted media (e.g., sediment, water or air) included in a DU would be collected and sent to the laboratory for analyses. This is ...
 

4.2 Use Of Multi Increment Samples To Characterize DUs
...or for liquid-based chemicals that were released in a uniform manner (e.g., sprayed, water-based pesticides). A minimum of 75 increments per sample is recommended for contaminants ...
 
...soil should normally be accompanied by the concurrent or followup collection of groundwater (Section 6) and/or soil vapor samples (see Section 7). Volatile chemicals ...
 
...hazards. These concerns can be more directly addressed through testing of groundwater and soil vapors. 4.2.4 INCREMENT DISTRIBUTION ...
 
...and clay more strongly than the parent compounds. Volatilization from moist soil and water surfaces will not be significant. This is supported by high concentrations of mercury in ...
 
...with diesel and other middle distillate fuels is no longer required (tested for groundwater only; refer to Section 9). Note also that naphthalene can be reported under most VOC ...
 
...vapor intrusion hazards associated with volatile contaminants in soil (and groundwater). Soil gas data are also very useful for identifying and locating areas of heavy contamination. ...
 
...Evaluation of Environmental Hazards at Sites with Contaminated Soil and Groundwater (HDOH, 2011) and Section 7 of this TGM for additional information. ...
 
...contaminants are found in surface soils above HDOH EALs; Groundwater data suggest that a release has occurred and contamination has migrated through the ...
 
...the collection of soil gas samples for volatile contaminants or testing of groundwater for contaminants that pose potential leaching hazards. Sampling constraints and potential ...
 

4.4 Common DU-MIS Investigation Mistakes And Problems
...apply to the characterization of sediment that happens to be covered by a layer of water. Simplistic contouring between discrete sample points cannot be assumed to be reliable ...
 

Contents
... Use of a Vibracore Device to Collect Sediment Samples in Deep Water   ...
 

5.1 Initial Site Inspection
...For example check for potential irrigation lines in landscaped areas or obviously well-watered lawns or shallow electrical conduits attached to sidewalk lighting. Look for sprinkler ...
 
...shallow electrical conduits attached to sidewalk lighting. Look for sprinkler heads and water piping or electrical conduits extending from buildings or outside air conditioning units, water ...
 
...piping or electrical conduits extending from buildings or outside air conditioning units, water heaters, etc. Note the presence of overhead utilities, trees or structures that might ...
 
... likely to be encountered in the subsurface, as well as the anticipated depth to groundwater. Direct push rigs are preferable for the collection of continuous cores and subsurface Multi ...
 

5.2 Site Preparation
...should not be limited to the following: Utilities (e.g., Board of Water Supply, Hawaiian Electric); Communication companies (e.g., cable/telephone ...
 
...lines, including lines for electric, gas, telecommunications, cable, water and sewer facilities. (www.DigSafelyHawaii.com) ...
 
...often represent trenches dug for installation or subsequent repair of subsurface water, fiber optic or electric lines, or other types of pipeline (e.g., stormwater). Rectangular ...
 
...fiber optic or electric lines, or other types of pipeline (e.g., stormwater). Rectangular patches a few hundred square feet or smaller in area might indicate the location ...
 
...if samples are to be collected. Hand digging, or other methods such as air or water jetting, may be required at some facilities. The latter can pose problems with the integrity ...
 
...a means of measuring the electrical conductivity of subsurface soil, rock, and ground water. Electrical conductivity (the inverse of electrical resistivity) is a function of the type ...
 
...however, obscure imaging of deeper features. High soil moisture, particularly in saltwater or brackish environments, can also mask subsurface features. ...
 

5.4 Subsurface Soil Sample Collection
...4.2). The same applies to characterization of sediment that is covered by a layer of water. Shallow subsurface soil (e.g., <12-18 inches bgs) might be accessible using ...
 
...for MI sampling strategies. Push rigs can also be used to collect soil gas or groundwater samples. Soil gas sampling is discussed in Section 7. The use of push rigs ...
 
...Section 7. The use of push rigs to install small-diameter monitoring wells for groundwater collection is discussed in Section 6.2. Smaller track-mounted rigs could be ...
 
...Plastic sheeting on the ground keeps potentially contaminated soil and water brought up by the auger from mixing with surface soils or impacting the pavement. ...
 
...are to be collected for contaminant analysis. On occasion, potable or distilled water may need to be added, but only in the situation that cuttings cannot be brought to the ...
 

5.6 Collection Of Multi Increment Samples For VOC Analysis
...amounts of either methanol (most common) or reagent-grade (e.g., distilled) water. However, the use of reagent-grade water for preservation is not recommended by the HEER ...
 
...However, the use of reagent-grade water for preservation is not recommended by the HEER Office due to concerns regarding extraction ...
 
... storing and shipping the flammable solution around the islands. The use of water as an extraction solution is not recommended (See Section 11.2. This approach was ...
 
...for volatile chemicals, which is more than adequate for screening purposes. The water-based extraction is also significantly less effective in comparison to methanol according ...
 
...concentration in the sample collected. In addition, VOCs will be less tightly held in water than in methanol and can be lost when the sample bottle is opened repeatedly to add increments. ...
 
... The use of an acidic, sodium bisulfate solution as an alternative to water provides both an extended holding time (up to 14 days) and allows for similarly low detection ...
 
...temperatures between -7°C and -15°C (for temporary storage and shipping) use water ice with added salt (Hewitt, 1999), and document that suitable freezing temperatures ...
 

5.7 Sediment Sampling
...ends attached to cut PVC, with solid cap on end of one piece, to keep the water out. Bottom left photo: Two-foot long, one-inch aluminum sampling tube (thin-walled ...
 
...two metal hose clamps. The bottom piece of PVC is sealed to keep mud and water out. (Examples in Figure 5-37 made by Weston Solutions, not patented) ...
 
...tube slightly backward before pushing out sample in order to drain excess water, being careful not to lose the sediment. Bottom right photo: Increment collected ...
 
...many sources including Superfund Program, Representative Sampling Guidance, Volume 5: Water and Sediment (USEPA, 1995c), USGS National Field Manual for the Collection ...
 
... Sediment (USEPA, 1995c), USGS National Field Manual for the Collection of Water-Quality Data (USGS, 2005), and Field Sampling Procedures Manual (NJDEP, 2005). ...
 
...the collection of Multi Increment samples from sediment in relatively shallow water (e.g., <15 ft deep) does not involve significantly more effort than required for the ...
 
...for collecting sediment samples. Consider the type and characteristics of the water body associated with the sediment to be sampled when selecting sampling equipment. Factors ...
 
...width, depth (especially if tidally influenced), flow, and bed characteristics of the water body are important. Increments collected from sediment should be core-shaped ...
 
...increment positions marked by pins or flags can also be placed along the edge of the waterway to guide sample collection (Figure 5-41). Refer to Section 4.2.5.1 for ...
 
... then the resulting Multi Increment sample will not be representative. Decant excess water from collected sediment Multi Increment sample by waiting several minutes and then carefully ...
 
...Multi Increment sample by waiting several minutes and then carefully pouring excess water out of the container. Use a cellulose paper filter to catch and re-place fine sediment ...
 
...methods are required for the collection of sediment samples from larger and/or deeper water bodies. Figure 5-42 depicts a core sampler used to collect Multi Increment sediment samples ...
 
...as the core is extracted from the increment location. As the core is being from the water, the base of the sampling tube is capped to prevent sediment loss. The sampling tube is ...
 
...was used to evaluate the feasibility of collecting Multi Increment samples from deep-water (50 ft) in a field study carried out by HDOH in 2013 (Figure 5-45). A small pontoon boat ...
 
... Figure 5-45. Use of a Vibracore Device to Collect Sediment Samples in Deep Water Left Photo: Vibracore sediment ...
 
...States Geological Survey (USGS), National Field Manual for the Collection of Water-Quality Data, Book 9, Handbooks for Water-Resources Investigations, Chapter A8, Bottom-Material ...
 
...Data, Book 9, Handbooks for Water-Resources Investigations, Chapter A8, Bottom-Material Samples. Version 1.1. June ...
 
...the laboratory data on a dry weight basis. If both sediment and surface water samples are collected in the same location, collect the surface water sample first. If ...
 
...samples are collected in the same location, collect the surface water sample first. If several sediment samples are collected from a streambed, collect the most ...
 

5.8 Field Documentation
... Depth to water table ...
 
... Dry - Absence of moisture, dry to the touch. Moist - No visible water but moisture is sufficient to bind soil matrix. Wet - Visible water, ...
 
...but moisture is sufficient to bind soil matrix. Wet - Visible water, usually when soil is sampled from a water table. In other instances, the wetness may ...
 
...usually when soil is sampled from a water table. In other instances, the wetness may also indicate the presence of non-aqueous ...
 
...Liquid (NAPL) contamination in soil (i.e., separate phase liquid not dissolved into water). The staining or moisture indicative of NAPL is often gray to brown in hue but can range ...
 
...by a sweet odor, while lubrication oil is most commonly much more viscous than water and accompanied by a dark color and a heavy, musky odor. Appearance of coarser ...
 
...in either lava type. All of these may indicate preferential pathways for groundwater travel. Tuff (T) � Descriptions of tuff should include boring ...
 
...type should pay primary attention to characteristics that potentially affect groundwater behavior (e.g. basalt fracturing, carbonate porosity). An example rock description is as ...
 

5.9 Equipment Preparation / Decontamination
... sampling equipment by hand; Wash with light detergent; Rinse with tap-water; Rinse a second time with tap-water. The use of solvents to clean ...
 
... Rinse a second time with tap-water. The use of solvents to clean equipment should be avoided in order to minimize ...
 
...These procedures may not be adequate for decontamination of equipment used to collect water samples (refer to Section 6). Carry multiple sets of sampling tools in order to expedite ...
 
...for the advancement of any sampling device must be steam cleaned or high pressure/hot water washed between DU locations. Examples of these types of equipment include auger flights, ...
 
...for "ultraclean" sampling approaches most typically associated with the collection of water samples, where parts-per-trillion level accuracy of laboratory data is desired. The collection ...
 

6.0 Groundwater and Surface Water Sampling Guidance
... ' SECTION 6 GROUNDWATER AND SURFACE WATER SAMPLING GUIDANCE Interim Final-December 31, 2008 ...
 
...AND SURFACE WATER SAMPLING GUIDANCE Interim Final-December 31, 2008 ...
 

Contents
... 6.0 Groundwater and Surface Water Sampling Guidance ...
 
...and Surface Water Sampling Guidance   ...
 
... 6.1 Groundwater Monitoring Well Placement   ...
 
... 6.1.1 Initial Groundwater Investigation Phase   ...
 
... 6.3 Groundwater Gauging   ...
 
... 6.3.2 Depth-to-Water Measurement   ...
 
... 6.5 Groundwater Sample Collection Methods   ...
 
... 6.5.7 Order of Groundwater Sampling   ...
 
... 6.6 Filtration of Groundwater Samples   ...
 
... 6.8 Groundwater Modeling   ...
 
... 6.9 Surface Water Sample Collection Methods   ...
 
... 6.9.1 Sampling Flowing and Still Surface Waters   ...
 
... 6.9.5 Lake/Standing Water Sampling   ...
 
... 6-1 Diagram of a Typical Groundwater Monitoring Well   ...
 
... 6-10 Oil-water Interface Meter   ...
 
... 6-11 Example Groundwater Sampling Log   ...
 
... 6-15 Bailers for Purging and Groundwater Sampling   ...
 
... 6-1 Test Methods for water Quality Parameters   ...
 
... Potential for Representative Analytical Results for commonly Utilized Groundwater Sampling Methods for Common Contaminants of Potential Concern ...
 

6.0 Groundwater and Surface Water Sampling Guidance
... ' 6.0 GROUNDWATER AND SURFACE WATER SAMPLING GUIDANCE The sampling guidelines presented in this section ...
 
...AND SURFACE WATER SAMPLING GUIDANCE The sampling guidelines presented in this section are intended to ensure ...
 
... The sampling guidelines presented in this section are intended to ensure that water samples collected as part of an environmental investigation are representative of ...
 
...an environmental investigation are representative of the in-situ condition of the groundwater or surface water, and that data derived from these samples can be used for decision making ...
 
...or surface water, and that data derived from these samples can be used for decision making purposes. This section ...
 
...as well as an overview of sampling equipment available for the collection of groundwater or surface water samples. This section refers to information in other TGM sections ...
 
...or surface water samples. This section refers to information in other TGM sections that are relevant to ...
 
... This section refers to information in other TGM sections that are relevant to groundwater and surface water sampling. For instance, site investigations may sometimes feature ...
 
... and surface water sampling. For instance, site investigations may sometimes feature groundwater as the sole media ...
 
...sampling. For instance, site investigations may sometimes feature groundwater as the sole media of concern, but groundwater sample collection is most frequently performed ...
 
...as the sole media of concern, but groundwater sample collection is most frequently performed as part of a larger investigation that also ...
 

Figures
... 6-1 Diagram of a Typical Groundwater Monitoring Well   ...
 
... 6-10 Oil-water Interface Meter   ...
 
... 6-11 Example Groundwater Sampling Log   ...
 
... 6-15 Bailers for Purging and Groundwater Sampling   ...
 

Tables
... 6-1 Test Methods for water Quality Parameters   ...
 
... Potential for Representative Analytical Results for commonly Utilized Groundwater Sampling Methods for Common Contaminants of Potential Concern ...
 

6.1 Groundwater Monitoring Well Placement
... ' 6.1 GROUNDWATER MONITORING WELL PLACEMENT The SAP must identify the site-specific monitoring well design ...
 
...3) that describe the site topography, the geologic setting, and the presumed groundwater hydrology The area of environmental concern The contaminants of potential concern ...
 
... The contaminants of potential concern Potential receptors such as potable water supply wells, irrigation wells, and surface streams connected to groundwater Influences ...
 
...supply wells, irrigation wells, and surface streams connected to groundwater Influences on hydrology such as injection wells or tidal fluctuation ...
 
...such as injection wells or tidal fluctuation 6.1.1 Initial Groundwater Investigation Phase The initial investigation phase described in this section assumes ...
 
...(1) a single point source or area of suspected contamination, and (2) prior groundwater investigation has not been conducted. The preliminary conceptual model (see ...
 
...published reports such as the Aquifer Identification and Classification Reports: Groundwater Protection Strategy for Hawai`i (Mink, J.F. and L.S. Lau, 1990a; 1990b; 1992; ...
 
...Lau, 1990a; 1990b; 1992; 1992b; 1993; 1993b), published by the Water Resources Research Center at the University of Hawai`i. The initial phase of the ...
 
...phase of the investigation determines whether contaminants have impacted the uppermost water bearing zone including perched groundwater. During this phase, a minimum of three wells are ...
 
...bearing zone including perched groundwater. During this phase, a minimum of three wells are required for each known or suspected contaminant ...
 
...angles relative to one another, will provide sufficient data to establish the local groundwater flow direction through static groundwater level measurements. Place at least ...
 
...flow direction through static groundwater level measurements. Place at least one of these wells in proximity to the source area ...
 
... During the initial investigation phase, the well screens must extend across the water table and groundwater sampling must include the uppermost water bearing zone, including perched ...
 
...table and groundwater sampling must include the uppermost water bearing zone, including perched groundwater. Monitoring ...
 
...sampling must include the uppermost water bearing zone, including perched groundwater. Monitoring wells with screens extending across ...
 
...bearing zone, including perched groundwater. Monitoring wells with screens extending across the water table are typically installed with ...
 
...Monitoring wells with screens extending across the water table are typically installed with 7 feet of screen interval below the water table (i.e., the ...
 
...table are typically installed with 7 feet of screen interval below the water table (i.e., the saturated interval) and 3 feet of screen interval above the water ...
 
... table (i.e., the saturated interval) and 3 feet of screen interval above the water table. This allows for the assessment of groundwater level fluctuations as well as ...
 
... table. This allows for the assessment of groundwater level fluctuations as well as the accumulation of free product on the water table surface. ...
 
...level fluctuations as well as the accumulation of free product on the water table surface. 6.1.2 Subsequent Investigation Phases If contamination ...
 
... wells may be required to delineate the horizontal and/or vertical extent of the groundwater contamination plume. In general, contamination resulting from petroleum products (which are ...
 
...In general, contamination resulting from petroleum products (which are less dense than water, and float) requires less vertical delineation than contamination resulting from chlorinated ...
 
...delineation than contamination resulting from chlorinated solvents (which are denser than water, and sink). To delineate the horizontal extent of groundwater impacts, monitoring ...
 
... and sink). To delineate the horizontal extent of groundwater impacts, monitoring wells are installed cross gradient, up gradient, and down gradient of the ...
 
...important if one or more contaminants of concern occur naturally in the soil and groundwater at the site. To delineate the vertical extent of groundwater impacts, monitoring wells ...
 
...at the site. To delineate the vertical extent of groundwater impacts, monitoring wells are installed with successively deeper screen intervals. Screen intervals ...
 
...confining units between upper and lower aquifers to prevent the vertical spread of groundwater contamination. When possible, drill to and collect geotechnical samples from the confining ...
 
...be required to establish that the confining unit is impermeable and that the underlying water bearing unit is not hydraulically connected to the impacted upper water bearing u...
 
... bearing unit is not hydraulically connected to the impacted upper water bearing unit. ...
 

6.2 Monitoring Well Installation and Abandonment
...of the potential presence, extent, and movement of contaminant plumes in groundwater, as well as the assessment of aquifer characteristics (for use in groundwater models). Monitoring ...
 
...as well as the assessment of aquifer characteristics (for use in groundwater models). Monitoring wells must therefore facilitate hydrologic testing and facilitate the collection ...
 
...facilitate hydrologic testing and facilitate the collection of representative groundwater samples. There is no "typical" monitoring well for achieving this objective. ...
 
...and materials are a function of the anticipated nature of the contaminants, groundwater quality, desired sampling depth(s), the aquifer's lithology and its overburden, the borehole ...
 
...or smaller diameter well. To ensure that samples are representative of groundwater conditions, monitoring well design should reflect anticipated contaminant properties. For example, ...
 
... contaminant is a light non-aqueous phase liquid (LNAPL), it will float on top of the water table; in this case, the well screen must be installed across the water table. If the contaminant ...
 
...table; in this case, the well screen must be installed across the water table. If the contaminant is a dense non-aqueous phase liquid (DNAPL), it will sink ...
 
...screen must provide access to the bottom of the aquifer. If the contaminant is soluble in water, it may impact the entire saturated zone; in this case, multiple screen intervals may be required ...
 
...into the aquifer or for contaminant transport between hydraulically separated water bearing units. 6.2.1 Permanent Monitoring Wells All permanent groundwater ...
 
...units. 6.2.1 Permanent Monitoring Wells All permanent groundwater monitoring wells have certain design components in common (USEPA, 1991a). A schematic of a ...
 
...have certain design components in common (USEPA, 1991a). A schematic of a standard groundwater monitoring well is presented in Figure 6-1. The monitoring well design components ...
 
... Figure 6-1. Diagram of a Typical Groundwater Monitoring Well This illustration shows the screen interval across the water table, ...
 
...Monitoring Well This illustration shows the screen interval across the water table, which is used for the assessment of LNAPLs. [Source: US Navy, 2007.] ...
 
...well riser and a well screen, which keeps the borehole open and provides access to groundwater for the collection of a water sample. The casing should always include a bottom cap to exclude ...
 
...for the collection of a water sample. The casing should always include a bottom cap to exclude material from entering ...
 
...from entering the bottom of the well and a top cap to exclude surface material or water from entering the well from the surface. Well casing materials include steel, ...
 
... depending on the objective of the well installation (e.g., site investigation or groundwater remediation) and the proposed monitoring and test equipment. When practical, the casing diameter ...
 
...4 inches to avoid generating large volumes of potentially contaminated soil and groundwater requiring management and disposal during well installation, development and purging activities. ...
 
... 1991a; CalEPA, 1995b). The casing material must not alter the groundwater chemistry by leaching, sorbing or desorbing It must be strong enough to withstand ...
 
...consisting of clean silica sand is installed around the well screen and allows groundwater to flow into the monitoring well for the collection of groundwater samples. ...
 
...to flow into the monitoring well for the collection of groundwater samples. Figure 6-3. Hollow Stem Auger with PVC ...
 
...see the following: Standard Practice for Design and Installation of Ground Water Monitoring Wells, (ASTM, 2004a). Handbook of Suggested Practices for the Design ...
 
... (ASTM, 2004a). Handbook of Suggested Practices for the Design and Installation of Groundwater-Monitoring Wells (USEPA, 1991a). Test Methods for Evaluating Solid Waste, Volume ...
 
...and Construction for Hydrogeologic Characterization, Guidance Manual for Ground Water Investigations (CalEPA, 1995b). The Chemical Composition of Leachate from a Two-Week Dwell-Time ...
 
...1988). Sorption of Aromatic Hydrocarbons by Materials Used in Construction of Ground-Water Sampling Wells (Gillham et. al., 1990). Adsorption of Selected Organic Contaminants ...
 
...of Four Well Casing Materials for Monitoring Selected Trace Level Organics in Ground Water (Parker et. al., 1989). In general, the well riser and well screen should be of ...
 
...filter pack material (USEPA, 1991a). For typical investigations of shallow groundwater in Hawai`i, a 2-inch diameter PVC casing with a screen slot size of 0.020 inches combined ...
 
...typical shallow monitoring wells are constructed with 7 feet of screen interval below the water table (i.e., the saturated interval) and 3 feet of screen interval above the water table. This ...
 
...table (i.e., the saturated interval) and 3 feet of screen interval above the water table. This allows for the assessment of groundwater level fluctuations as well as the accumulation ...
 
...table. This allows for the assessment of groundwater level fluctuations as well as the accumulation of free product on the water table surface. ...
 
...level fluctuations as well as the accumulation of free product on the water table surface. The casing at the bottom of the well screen must be closed against soil ...
 
...solid riser below the screen may lead to stagnant environments, which may alter the groundwater chemistry (USACE, 1998). The total borehole depth should not be more than 1 ...
 
...the planned bottom of the monitoring well in order to avoid preferential vertical groundwater flow originating from below the well screen. If a borehole extends greater than 1 meter ...
 
...well screen to 2 to 5 feet above the well screen, if feasible. In areas of shallow groundwater, a site-specific plan is recommended before installation of the wells begins. The filter pack ...
 
...the annular seal. Predevelopment may be necessary in aquifers of low permeability. Clean water may be circulated down the well through the screen into the filter pack and out of the top ...
 
... and out of the top of the borehole to aid in removal of the fines (USACE, 1998). All water introduced into the borehole must be removed. It is therefore important to record the water ...
 
...introduced into the borehole must be removed. It is therefore important to record the water volume injected and the water volume removed from the well. Do not use this technique if the ...
 
...volume injected and the water volume removed from the well. Do not use this technique if the borehole bridges water bearing ...
 
...volume removed from the well. Do not use this technique if the borehole bridges water bearing units that are not hydraulically connected, since it may induce cross contamination. ...
 
...upon hydration. Neat cement is a mixture of Portland cement (Type I for general use) and water, at a ratio of 5 to 6 gallons of water per 94-pound bag of cement. The grout must have a minimum ...
 
...at a ratio of 5 to 6 gallons of water per 94-pound bag of cement. The grout must have a minimum design strength of 2,500 pounds per ...
 
...seal material and placement is dependent upon whether the screen interval is below the water table (fully saturated screen interval) or extends across the water table. For ...
 
...table (fully saturated screen interval) or extends across the water table. For a fully saturated screen interval, a 3 to 5 foot thick bentonite seal, if ...
 
...seal, if feasible, is installed above the filter pack. In areas of shallow groundwater, a site-specific plan is recommended before installation of the wells begins. Pelletized bentonite ...
 
...seal can be installed through the use of a slurry mixed from powdered bentonite and clean water. It must contain a minimum of 20 percent solids by weight and have a density of 9.4 pounds ...
 
...denser and may intrude into the slurry. For screen intervals extending across the water table, a 3 to 5 foot thick bentonite seal is also installed above the filter pack. Bentonite ...
 
...box must be set slightly above the surrounding elevation to prevent pooling of surface water on the well. Provide protection from infiltration into the annular space by installing a surface ...
 
...from infiltration into the annular space by installing a surface seal made of a water-tight material such as neat cement or concrete. Install the surface seal on top of the ...
 
...concrete apron must slope away from the well (a minimum of 1 percent) to prevent surface water leakage into the well head. A flush mounted well head box during installation is illustrated ...
 
...lot is illustrated in Figure 6-5. The top of the well casing should be closed with a water tight cap, such as a compression cap. Protect the well head from unauthorized ...
 
...to bottom and top of annular grout Depth to bottom of surface seal Depth to the water table Surface seal and well apron design Protective box/casing and cap designs ...
 
...Well Survey All wells being used to assess the hydraulic gradient and the groundwater flow direction must be surveyed by a licensed professional surveyor. Record the well locations ...
 
...well, the filter pack and the adjacent formation. Development must extract a sufficient water volume from the well casing, filter pack, and adjacent formation such that the resulting inflow ...
 
...and adjacent formation such that the resulting inflow is representative of the groundwater flow in the surrounding aquifer. Final well development proceeds after well installation ...
 
...(CalEPA, 1995b; USACE, 1998). During well development by pumping, water is extracted from the well at high rates, dislodging and removing loose material in the process. ...
 
...rod or stem and operated by a drill rig. The movement of the surge block pushes and pulls water through the well screen, dislodging fine particulates from the screen, filter pack and adjacent ...
 
...from the screen, filter pack and adjacent formation. Surging is alternated with groundwater pumping to remove groundwater and sediment accumulated in the well during surging. Use of ...
 
...pumping to remove groundwater and sediment accumulated in the well during surging. Use of a vented, rather than un-vented, ...
 
... a vented, rather than un-vented, surge block is recommended to minimize the volume of water in the well that is forced into the formation on the down stroke of the surge block. ...
 
...down stroke of the surge block. During well development by backwashing, water is pumped through the well into the filter pack and formation. The backwashing dislodges particulates ...
 
...stuck in the well screen and filter pack. Backwashing is alternated with groundwater pumping to remove groundwater and the sediment suspended in the groundwater due to well development. ...
 
...pumping to remove groundwater and the sediment suspended in the groundwater due to well development. A combination of surging, ...
 
...and the sediment suspended in the groundwater due to well development. A combination of surging, backwashing, and pumping may be used to ...
 
...by bailing, a bailer is used in a similar manner as a surge block to agitate the well water and dislodge particulates in the filter pack and well screen. After surging, water is removed ...
 
...and dislodge particulates in the filter pack and well screen. After surging, water is removed from the well by withdrawing the full bailer to the surface. When surging with a ...
 
...with a bailer, a surging period of 10 to 20 minutes is recommended prior to removing water from the well. During well development by high velocity hydraulic jetting, water is jetted ...
 
...from the well. During well development by high velocity hydraulic jetting, water is jetted through the well screen from several horizontal jets. The water jet dislodges particulates ...
 
...is jetted through the well screen from several horizontal jets. The water jet dislodges particulates from the well screen, filter pack and adjacent formation. Hydraulic ...
 
...screen, filter pack and adjacent formation. Hydraulic jetting is alternated with groundwater pumping to remove groundwater and sediment accumulated in the well by jetting. ...
 
...pumping to remove groundwater and sediment accumulated in the well by jetting. When using water during drilling, ...
 
...and sediment accumulated in the well by jetting. When using water during drilling, pre-development or hydraulic jetting, at least three times the volume of water ...
 
...during drilling, pre-development or hydraulic jetting, at least three times the volume of water added should be removed during well development. The following criteria are typically ...
 
... 2002b): Removal of at least three times the calculated volume of standing water in the well. The calculated volume of standing water should include the saturated filter ...
 
...in the well. The calculated volume of standing water should include the saturated filter pack (assuming 30 percent porosity of the filter pack). ...
 
...filter pack (assuming 30 percent porosity of the filter pack). The well water pH stabilizes to within plus or minus (±) 0.1 pH units for three successive readings. ...
 
...successive readings. Readings are separated by the removal of one well volume of water. Well water temperature stabilizes to within ±1 degree Celsius. Well water ...
 
... Well water temperature stabilizes to within ±1 degree Celsius. Well water conductivity stabilizes ...
 
...temperature stabilizes to within ±1 degree Celsius. Well water conductivity stabilizes to within ±3 percent. Well water oxidation-reduction potential ...
 
...conductivity stabilizes to within ±3 percent. Well water oxidation-reduction potential stabilizes to within ±10 millivolts. Well water dissolved ...
 
...oxidation-reduction potential stabilizes to within ±10 millivolts. Well water dissolved oxygen concentration stabilizes to within ±0.3 milligrams per liter. ...
 
...stabilizes to within ±0.3 milligrams per liter. The well water is clear to the unaided eye, in areas where the local groundwater is known to be clear ...
 
...is clear to the unaided eye, in areas where the local groundwater is known to be clear and the turbidity readings are below 10 nephelometric turbidity ...
 
...percent at concentrations larger than 10 NTU. In areas of known turbid groundwater, the final well water may be turbid to the eye. The sediment thickness in the ...
 
...the final well water may be turbid to the eye. The sediment thickness in the well is less than 1 percent ...
 
...less than 10 feet long. Use the methods listed in Table 6-1 to determine the water quality parameters. For the specific methods refer to the USEPA document entitled "Methods ...
 
...specific methods refer to the USEPA document entitled "Methods for Chemical Analysis of Water and Wastes" (USEPA, 1983) and the ASTM standards identified in Table 6-1. ...
 
... ASTM standards identified in Table 6-1. Table 6-1 Test Methods for Water Quality Parameters Water Quality Parameter ...
 
...Quality Parameters Water Quality Parameter EPA Method ...
 
... If the well recharge rate is so slow that (1) the required water volume cannot be removed within 48 hours of development, (2) excessive sediment remains in ...
 
... During all purging and sampling activities, prevent potentially contaminated water from spilling onto the ground surface surrounding the well. All water and sediment ...
 
... from spilling onto the ground surface surrounding the well. All water and sediment extracted during well development must be placed in containers conforming to requirements ...
 
...for each monitoring well. ASTM Standard D5521 (ASTM, 2005a) presents additional guidance on groundwater well development. An example well development log is illustrated on Figure 6-8. ...
 
... Date and time of well development Well development technique Average pumping or water extraction rate Estimated recharge rate Static water level from top of casing before ...
 
...extraction rate Estimated recharge rate Static water level from top of casing before development Sediment level from top of casing prior to development ...
 
...before development Sediment level from top of casing prior to development Static water level from top of casing- 24 hours after development Sediment level from top of casing- 24 ...
 
...of liquids lost into well during drilling, predevelopment and development Volume of water standing in the well casing and saturated filter pack, assuming a 30 percent filter pack ...
 
...pack porosity A running log of: Time Water volume removed, both incremental and total Field measurement of pH, temperature, conductivity, ...
 
... particulates, etc. Total volume of water removed Total time needed for development Investigation derived waste (IDW) inventory ...
 
...than 7 days after well completion. The HEER Office recommends that groundwater gauging, purging and sampling be conducted no sooner than 14 days after well development. The ...
 
...from other agencies for the time interval between monitoring well completion and groundwater sample collection ranges from 24 hours (US Navy, 2007) to 48 hours (SC DHEC, 2005) to several ...
 
...2008.] 6.2.2 Temporary Monitoring Wells Temporary groundwater monitoring wells or sampling points are generally installed in boreholes driven by direct push ...
 
... according to the procedures outlined in Subsection 6.4. The use of temporary groundwater monitoring wells is not as rigorous as the construction and development of permanent groundwater ...
 
...wells is not as rigorous as the construction and development of permanent groundwater monitoring wells, and the samples collected may not be representative of the aquifer. However, ...
 
...lower cost alternative to the initial characterization or delineation of potential groundwater impacts. While the use of temporary monitoring wells may be advantageous in some instances, ...
 
...advantageous in some instances, they are not suitable for long-term monitoring of groundwater or for final decision making purposes. The intended use of data collected from temporary monitoring ...
 
...the HEER Office. 6.2.3 Other Wells Other wells used for groundwater sampling include micro wells, existing production wells and potable wells. The following sections ...
 
... 6.2.3.2 Production/ Potable Well Sampling Collection of water samples for analysis from wells other than groundwater monitoring wells should be approved ...
 
...samples for analysis from wells other than groundwater monitoring wells should be approved by the HEER Office. The request should be accompanied by ...
 
...and depth, seal material and depth Elevation of screen interval Depth to groundwater table and bottom of unconfined aquifer Depth to top and bottom of confined aquifer(s) ...
 
...data A description of how the sampling data will be used Collect raw water samples from a supply well as close to the well head as possible (before any treatment). Purge ...
 
...any treatment). Purge the well long enough to obtain a representative sample of groundwater with a minimal residence time in the collection/distribution system. The purge volume may be ...
 
...Downhole Equipment Dedicated sampling equipment that will reside within a groundwater monitoring well must not alter the chemistry of the groundwater and must be resistant to chemical ...
 
...monitoring well must not alter the chemistry of the groundwater and must be resistant to chemical or physical deterioration. Inspect the equipment periodically ...
 
...operation. The equipment must not interfere with aquifer tests, well maintenance, and water level measurements (CalEPA, 1995b). 6.2.4.2 Monitoring Wells at Sites with LNAPL ...
 
...where the free-phase plumes reside. For LNAPL plumes, provide sampling access across the water table and capillary fringe of the uppermost water bearing unit. If the aquifer in question ...
 
...table and capillary fringe of the uppermost water bearing unit. If the aquifer in question is tidally influenced, free phase liquid may be trapped ...
 
... free phase liquid may be trapped in pore spaces below the capillary fringe when the water table is at its highest and above the capillary fringe when the water table is at its lowest. ...
 
...table is at its highest and above the capillary fringe when the water table is at its lowest. In addition, provide access to the part of the aquifer ...
 
...at Sites with DNAPL Plumes Most DNAPLs that are commonly found in soil and groundwater contamination fall into four groups (USEPA, 2004c): Chlorinated solvents used ...
 
...gas plants (MGP) The tendency of DNAPLs to move independently of groundwater flow makes it difficult to delineate and remediate free phase DNAPL plumes. Most DNAPLs are ...
 
...locate and remediate the free phase plume. Most DNAPLs are relatively immiscible in water and tend to remain in a separate non-aqueous phase due to their low solubility. If their density ...
 
...phase due to their low solubility. If their density is sufficiently high compared to water density and they are present in a great enough free phase volume, they will sink through the ...
 
...with a high enough density, therefore, migrate vertically rather than following groundwater movement. In addition, they may migrate according to the slope of the uppermost confining unit, ...
 
...to the slope of the uppermost confining unit, which may differ from the regional groundwater flow direction. The migration of DNAPLs with a density (specific gravity) closer to ...
 
...of DNAPLs with a density (specific gravity) closer to 1 will be influenced by groundwater movement to a greater degree. The USEPA has published a guidance document that helps ...
 
...are not volatile and are not sufficiently soluble to be readily detectable in groundwater. The lighter end PCBs do have some solubility [3 milligram per liter (mg/L) range] and ...
 
...polynuclear aromatics are volatile and sufficiently soluble to be detected as a groundwater plume Coal tar creosote mixtures are very diverse and may or may not be associated with ...
 
...tar creosote mixtures are very diverse and may or may not be associated with groundwater plumes. They may contain several chemicals that fluoresce The HEER Office requires ...
 
...both the free phase and dissolved plumes are delineated at DNAPL sites. Borings and groundwater monitoring wells should be designed to accommodate the selected investigation techniques. ...
 
...many consequences. For example, in a hydraulically isotropic, porous formation, the groundwater flow direction is perpendicular to the equipotential lines of the water table or potentiometric ...
 
...flow direction is perpendicular to the equipotential lines of the water table or potentiometric map. This assumption cannot be made in a fractured formation, since ...
 
...layer or unit. The confining layer or unit, referred to as an aquitard, prevents water contained in the aquifer from rising to its elevation of hydraulic equilibrium. The ...
 
...installation that penetrates a confining unit becomes a potential pathway between the water bearing units and can result in cross contamination. In many cases, the overlying aquitard ...
 
...and wells that penetrate into the confined aquifer such that they do not open vertical water and contaminant pathways. Keep in mind that a well installed into a confined aquifer may be ...
 
...Monitoring Well Abandonment The purpose of well abandonment is to prevent surface water from infiltrating into the subsurface and to prevent vertical groundwater movement within the ...
 
...from infiltrating into the subsurface and to prevent vertical groundwater movement within the aquifer (HDLNR, 2004). By eliminating water movement vertically within ...
 
...movement within the aquifer (HDLNR, 2004). By eliminating water movement vertically within the former borehole, the borehole will cease to be a potential conduit ...
 
...be a potential conduit for contaminant dispersion (USEPA, 1991a). A groundwater monitoring well that is no longer needed, sustains damage serious enough to potentially affect ...
 
... 6.2.5.1 Well Abandonment Planning All soil borings and groundwater monitoring wells will eventually require decommissioning and closure in accordance with the ...
 
... Pressure grout the borehole to within 5 feet of ground surface or to above the groundwater table, whichever is shallower (CalEPA, 1995b). Pressure grouting is described ...
 
...casing. Pressure grout the well to within 5 feet of ground surface or to above the groundwater table whichever is shallower (CalEPA, 1995b). Pressure grouting is described ...
 
...with Clean Soil This option may be used only in areas where groundwater is not a current or potential source of drinking water or where contamination has not been ...
 
...is not a current or potential source of drinking water or where contamination has not been left on-site. Express advance approval must be obtained ...
 
...depth Backfill the borehole to within 5 feet of ground surface or to above the groundwater table whichever is shallower The backfill must be composed of silty clay or clayey ...
 
...this option Keep the moisture content of the soil at an optimum for compaction. Add clean water as needed Place the soil into the borehole in thin lifts and compact using mechanical ...
 
...ratio of one 94-pound sack of Portland cement to not more than six gallons of potable water. Concrete. Concrete shall contain 5.3 sacks of Portland cement per cubic yard of ...
 
...5.3 sacks of Portland cement per cubic yard of concrete and a maximum of 7 gallons of water per 94-pound sack of cement. The aggregate shall consist of 47 percent sand and 53 percent ...
 
...part sand to one part Portland cement, by weight, and not more than six gallons of water per sack of Portland cement. Clean well-sorted sand shall be used. Cement-Bentonite. A slurry ...
 
...sand shall be used. Cement-Bentonite. A slurry of Portland cement, bentonite and water. The amount of bentonite added shall not exceed 8% bentonite per dry weight of cement (7.5 ...
 
...weight of cement (7.5 pounds of bentonite per 94 pound sack of cement). The volume of water used in preparing these slurries is limited to three quarters (0.75) of a gallon per 94 ...
 
...It is not recommended to use neat cement in the saturated zone, particularly if the groundwater is acidic. Water with an acidic pH may corrode the cement (USEPA, 1991a). The rationale ...
 
...is acidic. Water with an acidic pH may corrode the cement (USEPA, 1991a). The rationale for the choice ...
 
...consideration of factors such as depth and width of the soil boring or well borehole, and water composition in the saturated zone. After grouting, all wells must be sounded to determine if ...
 
...compressive strength. One mix of cement-bentonite may be used for both the water-bearing and vadose zone when abandoning wells in locations where load-bearing is not a concern ...
 
... when abandoning wells in locations where load-bearing is not a concern and where groundwater is encountered at a depth of less than 20 feet below ground surface. 6.2.5.5 Well ...
 

6.3 Groundwater Gauging
... ' 6.3 GROUNDWATER GAUGING The purpose of groundwater gauging is to construct a groundwater table map or ...
 
...GAUGING The purpose of groundwater gauging is to construct a groundwater table map or a potentiometric surface map for the site ...
 
...gauging is to construct a groundwater table map or a potentiometric surface map for the site under investigation. The data are used ...
 
...The data are used to calculate the hydraulic gradient(s) and the horizontal groundwater flow direction(s) across the site. Therefore, all measurements must be taken within a 24-hour ...
 
...the contaminants present. The HEER Office requires a minimum of two rounds of groundwater gauging to verify the groundwater gradient(s) and flow direction(s). The two gauging events ...
 
...gauging to verify the groundwater gradient(s) and flow direction(s). The two gauging events must be separated by a minimum of ...
 
... On sites that are tidally influenced, perform a tidal study to determine the net groundwater flow direction. If site investigation, monitoring and remedial efforts continue over a year, ...
 
...monitoring and remedial efforts continue over a year, include seasonal groundwater gauging into the investigation to determine the influence of seasonal variations in the aquifer. ...
 
...the influence of seasonal variations in the aquifer. Correct the measured groundwater elevations for tidal influences, barometric influences, and overlying free product thickness. ...
 
...Monitoring Well Equilibration During well development, a large amount of groundwater is pulled through the surrounding formation as well as the filter pack and the well casing. ...
 
...This may disturb the chemical equilibrium of the surrounding formation with the groundwater. In addition, the filter pack may not reach chemical equilibrium with the aquifer. ...
 
...should be attained. This is especially important in low permeability aquifers, where water extraction during well development may draw down the aquifer adjacent to the well. ...
 
... down the aquifer adjacent to the well. The HEER Office recommends that groundwater gauging and sampling be conducted no sooner than 14 days after well development. However, equilibration ...
 
...equilibration is provided in Subsection 6.2.1.9. 6.3.2 Depth-to-Water Measurement Reference all water level measurements to the survey mark at the top of the ...
 
...Measurement Reference all water level measurements to the survey mark at the top of the casing. The reference point must be ...
 
...6.2.1.6, Well Survey. Use either a weighted steel tape with chalk or an electronic water level indicator to measure the depth to water (USEPA, 2002b and 1999a). Select the measuring ...
 
...level indicator to measure the depth to water (USEPA, 2002b and 1999a). Select the measuring device carefully for wells deeper ...
 
...at least 15 minutes prior to gauging to eliminate the effects of rising or falling water levels prior to the gauging event. Rising or falling water levels prior to removing the well ...
 
...levels prior to the gauging event. Rising or falling water levels prior to removing the well cap will create either pressure or a vacuum on the well that ...
 
...the well cap will create either pressure or a vacuum on the well that will impact the water level in the well unless sufficient time is allowed for the well to equilibrate. In ...
 
...submerged screens should be gauged continuously for several minutes to document that the water level has equilibrated. If groundwater sampling is to be completed on the same day, measure ...
 
...level has equilibrated. If groundwater sampling is to be completed on the same day, measure the depth to water prior to sampling. ...
 
...sampling is to be completed on the same day, measure the depth to water prior to sampling. Calculate the water table/potentiometric surface elevation by subtracting ...
 
...prior to sampling. Calculate the water table/potentiometric surface elevation by subtracting the depth to water from the reference ...
 
...table/potentiometric surface elevation by subtracting the depth to water from the reference point elevation. Correct elevations for tidal, barometric and free phase ...
 
...at least once to confirm the measurement (USEPA, 1999a). If groundwater sampling is to be completed on the same day, measure the total well depth after sampling has ...
 
...total well depth after sampling has been completed to prevent suspension of silt into the water column (USEPA, 1999a). Figure 6-10. Oil-water ...
 
... column (USEPA, 1999a). Figure 6-10. Oil-water Interface Meter [Source: Solinst, 2008] 6.3.4 Free Product Measurement ...
 
...Free Product Measurement Measure wells with free phase product last. Use an oil-water interface probe manufactured for use in free-phase product (See example in Figure 6-10). Measure ...
 
...surveyor's mark at the top of the casing. In LNAPL plumes, this would be on top of the water column; in DNAPL plumes at the bottom of the well. Correct the water table elevation ...
 
...column; in DNAPL plumes at the bottom of the well. Correct the water table elevation for the thickness of the free product floating on top of the water column. ...
 
...table elevation for the thickness of the free product floating on top of the water column. The corrections have to be based on the actual density of the LNAPL present at the ...
 
... 6.3.5 Well Gauging Log At a minimum record the following information on groundwater monitoring logs: Date Project name and location Field personnel ...
 
... Time of measurement Depth to free product Depth to groundwater Depth to bottom of well Observations (casing condition, well head ...
 
... etc.) Activities that may influence water level (groundwater pumping, irrigation, etc.) Decontamination procedures ...
 
...level (groundwater pumping, irrigation, etc.) Decontamination procedures ...
 
... 6.3.6 Tidal Effects Aquifers at sites in proximity of the ocean with water table or potentiometric surface elevations close to sea level often show tidal influences. ...
 
...sea level changes result in changes of hydraulic pressure at the shoreline, where groundwater flows into the ocean. As the tide rises, hydraulic pressure increases and causes backpressure ...
 
...may be necessary at sites that are tidally influenced. Continually gauge and record groundwater elevations at the site for a minimum period of 72 hours. Gauge at least three monitoring wells ...
 
...monitoring wells on small sites and more wells on larger sites. In addition, measure the water elevation in the ocean in a place protected from wave action. Enclose the pressure gauge in ...
 
...Synchronize data logging between all pressure gauges. Calculate the groundwater gradient and flow direction for each sampling time. Calculate the net groundwater gradient ...
 
...gradient and flow direction for each sampling time. Calculate the net groundwater gradient and net flow direction. Compare the times of tidal fluctuations between the ...
 
...ocean and each monitoring well to determine the tidal lag of each well. Compare the groundwater elevation changes within each well to the sea level changes to calculate the tidal efficiency ...
 
...each well to the sea level changes to calculate the tidal efficiency (percent of groundwater elevation change compared to sea level change). On a map, present the groundwater flow ...
 
...elevation change compared to sea level change). On a map, present the groundwater flow directions as they change throughout one tidal cycle. Present the groundwater gradient ...
 
...flow directions as they change throughout one tidal cycle. Present the groundwater gradient for each flow direction. In addition, present the net groundwater flow direction and ...
 
...gradient for each flow direction. In addition, present the net groundwater flow direction and gradient on the same map. If variations are seen between tidal cycles, present ...
 
...on a map. 6.3.6.2 Gauging at Tidally Influenced Sites Groundwater gauging at tidally influenced sites requires careful planning. Choose the date and time of ...
 
...half an hour between gauging other wells. Assume that the change in groundwater elevation within the reference well is linear throughout the half hour between measurements. ...
 
... throughout the half hour between measurements. Use the linear regression of the groundwater elevation change in the reference well to correct the groundwater elevations for all wells ...
 
...elevation change in the reference well to correct the groundwater elevations for all wells for tidal influence. On sites with large variations in tidal efficiency ...
 
...more than one reference well. 6.3.7 Seasonal Effects Groundwater flow may exhibit significant seasonal variations between the dry season and the wet season ...
 
...the wet season in Hawai`i. Characterizing seasonal and temporal variations in groundwater flow is important at sites where the groundwater flow direction may change due to seasonal ...
 
...flow is important at sites where the groundwater flow direction may change due to seasonal variations. It is also important for site investigations ...
 
...site investigations involving aquifer tests. Initially, weekly or monthly water level measurements may be needed to characterize seasonal fluctuations, followed by quarterly ...
 
... seasonal fluctuations, followed by quarterly or semi-annual monitoring after the water level variations have been described (CalEPA, 1995a). 6.3.8 Temporal Variations ...
 
...variations, the following processes can introduce temporal variations in the groundwater table/potentiometric surface and possibly in the groundwater flow direction (USEPA, 1992d; ...
 
...table/potentiometric surface and possibly in the groundwater flow direction (USEPA, 1992d; CalEPA, 1995a): Barometric effects Variations ...
 
... Identify and evaluate factors that result in short- or long-term variations in groundwater elevations and flow patterns. Measure the water levels frequently enough to detect ...
 
... elevations and flow patterns. Measure the water levels frequently enough to detect and characterize temporal variations in groundwater flow. ...
 
...levels frequently enough to detect and characterize temporal variations in groundwater flow. 6.3.9 Determination of Vertical Hydraulic Gradient and Flow Direction ...
 
...the vertical hydraulic gradient and flow direction on sites where vertical groundwater flow is significant. A deep vertical extent of a dissolved contaminant plume is an indication ...
 
...vertical extent of a dissolved contaminant plume is an indication that vertical groundwater flow is significant. To determine the vertical component of groundwater flow, install ...
 
...flow is significant. To determine the vertical component of groundwater flow, install multiple piezometers or wells in clusters or nests, or multi-level wells or sampling ...
 
...may cause disturbance in the formation around neighboring piezometers. Water levels measured in piezometers that are closely-spaced, but separated horizontally, may ...
 
... may produce imprecise information regarding the vertical component of groundwater flow Installation of multiple piezometers closely spaced or within ...
 
...entitled "Handbook of Suggested Practices for the Design and Installation of Groundwater-Monitoring Wells" (USEPA, 1991a) for a discussion of the advantages and disadvantages of ...
 
...site. The two or more measurement points must be aligned parallel to the horizontal groundwater flow direction. During groundwater gauging in the piezometers, follow the procedures ...
 
... flow direction. During groundwater gauging in the piezometers, follow the procedures for groundwater gauging detailed in Section ...
 
...gauging in the piezometers, follow the procedures for groundwater gauging detailed in Section 6.3. Calculate the vertical groundwater flow directions and ...
 
...gauging detailed in Section 6.3. Calculate the vertical groundwater flow directions and hydraulic gradient using the water level measurements. Generate a vertical ...
 
...flow directions and hydraulic gradient using the water level measurements. Generate a vertical cross section across the measuring points depicting ...
 
...flow net, piezometer screen depths and length of screen interval, geological units, and water bearing units. Refer for guidance (USEPA, 1989a; Cedergren, 1977; and Freeze ...
 

6.4 Purging
... ' 6.4 PURGING The purpose of well purging before groundwater sampling is to ensure that the samples will be representative of the groundwater and contaminant ...
 
...sampling is to ensure that the samples will be representative of the groundwater and contaminant levels in the vicinity of the well. If a well is left untended for prolonged ...
 
...levels in the vicinity of the well. If a well is left untended for prolonged periods, the water contained within the well and possibly within the filter pack may not be representative of ...
 
...within the filter pack may not be representative of the surrounding aquifer formation water. For example, water extending above or below the well screen may be stagnant and may have undergone ...
 
...For example, water extending above or below the well screen may be stagnant and may have undergone physiochemical ...
 
...through gas exchange with headspace, etc. Excessive purging may result in biased groundwater samples, since it may dilute or increase the contaminant concentrations at the sampling ...
 
...a purging device that will not alter the geochemical and physical parameters of the groundwater and dissolved contaminants or increase turbidity. Keep the contaminant characteristics in mind ...
 
...though due to the greater potential to alter geochemical and physical parameters of groundwater and other limitations, their use is generally limited to monitoring wells with specific characteristics ...
 
...the well screen. If purging above the well screen (if the screen interval is below the water table), start purging at the water table and gradually lower the pump so that it sits just ...
 
...table), start purging at the water table and gradually lower the pump so that it sits just above the top of the well screen at ...
 
...the top of the well screen at the end of purging. This will ensure that the stagnant water above the screen has been purged. It also ensures that during sampling, the groundwater has ...
 
...above the screen has been purged. It also ensures that during sampling, the groundwater has the shortest riser length to pass (USEPA, 2002b). If the intake is placed ...
 
...low-flow purging and sampling technique is used (USEPA, 2002b). All groundwater extracted from wells during purging must be properly containerized, staged, sampled, and disposed. ...
 
...purging must be properly containerized, staged, sampled, and disposed. Do not allow water to flow onto the ground. Place all downhole equipment onto a clean plastic sheet to ensure ...
 
...sheet to ensure that the ground around the well is not cross contaminated by groundwater, and to ensure that downhole equipment does not transfer surface materials into the well. ...
 
...and sampling approach be utilized whenever feasible to collect representative groundwater samples. The purpose of the low-flow purging is to sample a specific depth within a well ...
 
...slightly above the middle of the screen interval. Placement of the pump at the top of the water column for sampling is only recommended in unconfined aquifers, screened across the water table, ...
 
...column for sampling is only recommended in unconfined aquifers, screened across the water table, where this is the desired sampling point. Carefully place the pump into the well ...
 
...based on the assumption that under minimal drawdown the pump will not draw down stagnant water from the well portion above the pump. Therefore, the drawdown in the well must be kept at a ...
 
...exceed 0.33 feet or 0.1 meter (Puls and Barcelona, 1996). This involves regular water level measurements, i.e. gauging, throughout purging and subsequent sampling. Gauging intervals ...
 
... or dedicated manner. Throughout purging, regularly measure and record water quality parameters. Preferably, water quality parameters should be measured with a device that ...
 
...quality parameters. Preferably, water quality parameters should be measured with a device that prevents contact with air, such as ...
 
...The following criteria are typically achieved during well purging: Well water pH stabilizes to within ±0.1 pH units for three successive readings. Well ...
 
...stabilizes to within ±0.1 pH units for three successive readings. Well water temperature stabilizes to within ±1 degree Celsius. Well water conductivity stabilizes ...
 
...temperature stabilizes to within ±1 degree Celsius. Well water conductivity stabilizes to within ±3 percent. Well water oxidation reduction potential ...
 
...conductivity stabilizes to within ±3 percent. Well water oxidation reduction potential stabilizes to within ±10 millivolts. Well water ...
 
...oxidation reduction potential stabilizes to within ±10 millivolts. Well water dissolved oxygen concentration stabilizes to within ±0.3 milligrams per liter. ...
 
...concentration stabilizes to within ±0.3 milligrams per liter. Well water is clear to the unaided eye in areas where the local groundwater is known to be clear and ...
 
...is clear to the unaided eye in areas where the local groundwater is known to be clear and the turbidity readings are below 10 NTUs. Turbidity ...
 
...percent at concentrations larger than 10 NTU. In areas of known turbid groundwater, the final well water may be turbid to the eye. The HEER Office recommends ...
 
...the final well water may be turbid to the eye. The HEER Office recommends the use of flow-through ...
 
... The HEER Office recommends the use of flow-through cells when monitoring groundwater stabilization parameters during purging. Flow-through cells contain an inlet at the ...
 
...during purging. Flow-through cells contain an inlet at the bottom of a cup that purge water is pumped into. The water is allowed to overflow into a bucket during purging. The field instruments ...
 
...is pumped into. The water is allowed to overflow into a bucket during purging. The field instruments used to monitor ...
 
...the fixed well-volume purging approach is provided in "The Essential Handbook of Ground-Water Sampling" (Nielsen et. al., 2007). The well volume purging approach is described below as a ...
 
...the HEER Office. The purpose of the well volume approach is to remove all stagnant water or non-representative water within the well, the filter pack, and the adjoining formation. ...
 
...or non-representative water within the well, the filter pack, and the adjoining formation. For wells where the water ...
 
...within the well, the filter pack, and the adjoining formation. For wells where the water level is above the well screen (i.e., a fully saturated screen interval), start pumping near ...
 
...above the well screen (i.e., a fully saturated screen interval), start pumping near the water table and lower the pump slowly throughout the purging process. The final position of the pump ...
 
...of the pump should be just above the screen interval. For wells where the water level is within the well screen, set the pump to a level such that the drawdown does not allow ...
 
... liters per minute (USEPA, 2002b). Alternatively, use a bailer to remove groundwater from the well. Start bailing near the water table and keep lowering the bailer as purging continues. ...
 
...from the well. Start bailing near the water table and keep lowering the bailer as purging continues. Do not lower the bailer to a depth ...
 
...turbulence near the bottom of the well that could lead to suspension of sediment into the water column. Monitor water quality parameters after removal of each well volume (the well ...
 
...column. Monitor water quality parameters after removal of each well volume (the well volume includes the saturated ...
 
...pack volume). Continue purging until a minimum of three well volumes are removed and the water quality parameters have stabilized. The stabilization criteria typically monitored during purging ...
 
... where wells are slow to recover. In wells that are screened below the water table, purge water in storage in the well casing from above the screen, and avoid dewatering ...
 
...table, purge water in storage in the well casing from above the screen, and avoid dewatering and introducing air ...
 
...in storage in the well casing from above the screen, and avoid dewatering and introducing air into the well screen interval. Do not lower the pump into the well screen ...
 
...Do not lower the pump into the well screen interval, but pump from the top of the water column, following the water level down to the top of the screen. This procedure requires pumping ...
 
...column, following the water level down to the top of the screen. This procedure requires pumping at low rates to prevent ...
 
...not be utilized (USEPA, 2002b). In wells that are screened across the water table, it has been common practice to purge the well dry and let it recover for a minimum of ...
 
... purge the well dry and let it recover for a minimum of 2 hours and until sufficient water volume is present to take a water quality sample or the well has recovered to 90%. Although ...
 
...volume is present to take a water quality sample or the well has recovered to 90%. Although it is recognized that purging to ...
 
...for these low yield wells may be limited, especially in cases with less than 4 feet of water in the well and a depth to water of more than 20 feet (USEPA, 2002b). Another ...
 
...in the well and a depth to water of more than 20 feet (USEPA, 2002b). Another option is the use of "minimum-drawdown" ...
 
...purging for low yield wells as described in "Low-Flow (Minimal Drawdown) Ground-Water Sampling Procedures" (Puls and Barcelona, 1996). When sampling very low permeability wells, ...
 
...screen length Well purging technique Purging device Average pumping or water extraction rate Static water level from top of casing before purging Total well depth ...
 
...extraction rate Static water level from top of casing before purging Total well depth and presence/absence of sediment ...
 
...For well volume approach: measure total well depth before purging Water Volumes For well volume approach: calculate well volume For low-flow approach: calculate ...
 
...tube volume A running log of: Time Water volume removed both incremental and totalized For low-flow approach: water level and ...
 
...volume removed both incremental and totalized For low-flow approach: water level and drawdown Field measurement of pH, temperature, conductivity, oxidation reduction ...
 
...such as color, clarity, odor, particulates, etc. Total volume of water removed Total time needed for purging 15. IDW inventory including type and number ...
 
... Refer to Table 6-1 in Subsection 6.2.1.7 for methods to determine water quality parameters during purging. Figure 6-11 presents an example Groundwater Sampling Log ...
 
...quality parameters during purging. Figure 6-11 presents an example Groundwater Sampling Log containing locations for recording purging parameters prior to the collection ...
 
...containing locations for recording purging parameters prior to the collection of groundwater samples. Figure 6-11. Example Groundwater Sampling ...
 
...samples. Figure 6-11. Example Groundwater Sampling Log [Source: US Navy, 2007] ...
 

6.5 Groundwater Sample Collection Methods
... ' 6.5 GROUNDWATER SAMPLE COLLECTION METHODS The purpose of groundwater sampling is to collect samples representative ...
 
...SAMPLE COLLECTION METHODS The purpose of groundwater sampling is to collect samples representative for the aquifer at the well location. Consider ...
 
...the contaminant(s) such as volatility, solubility, density (denser or lighter than groundwater) and their resultant fate in the subsurface (adhesion to soil particles, biodegradation ...
 
...the sampling approach. The following sections describe different methods of groundwater sampling, the different types of equipment for each method, and details on the appropriate ...
 
...presents the potential for representative analytical results for commonly utilized groundwater sampling methods for common contaminants of potential concern. Table 6-2 ...
 
...Table 6-2 Potential for Representative Analytical Results for Commonly Utilized Groundwater Sampling Methods for Common Contaminants of Potential Concern ...
 
...bladder pump within a monitoring well In this illustration the water level is above the screen interval Figure 6-13. ...
 
... Figure 6-14. Field Setup for Purging and Sampling Well Purging and sampling of groundwater monitoring well using a portable low-flow bladder pump driven by a portable air compressor ...
 
... Figure 6-15. Bailers for Purging and Groundwater Sampling The following representative bailers are shown: ...
 
...Sampling The purpose of low-flow sampling is to collect representative groundwater samples for a specific depth within a well screen interval. The method is based on the assumption ...
 
... that given sufficiently low removal rates, a sampling pump will not draw stagnant water from the water column above and below the position of the pump. Therefore the rate of removal ...
 
...from the water column above and below the position of the pump. Therefore the rate of removal must be kept ...
 
...approach be utilized where appropriate and feasible to collect representative groundwater samples. Low-flow sampling is preceded by low-flow purging (see Subsection ...
 
...purging and sampling. Keep the pump rate throughout sampling low enough that the groundwater flow exiting from the discharge tube is laminar and does not induce turbulence in sampling ...
 
...enclosed by a rigid housing. In the most common application, a pump is inserted below the water table in a well, and water enters the housing under hydrostatic pressure through an intake ...
 
...table in a well, and water enters the housing under hydrostatic pressure through an intake check valve. When the housing ...
 
...intake check valve. When the housing chamber is full, the intake check valve prevents the water from escaping back out to the well. The bladder is inflated from a compressed gas source ...
 
... or pump at the surface, and the pressure generated by the inflating bladder pushes the water upwards through another discharge check valve, then through a discharge tube upwards to the ...
 
...6-13 and 6-14. 6.5.3 Submersible Pumps Submersible pumps move water up a well by applying positive pressure; however, instead of a pushing motion, submersible ...
 
...or centrifugal pumps typically use electric-motor driven impellers to drive the water to the surface. The impellor pressure is equal to the hydraulic head in the tubing extending ...
 
...site contaminants. Install a device that will prevent backflow to the pump to avoid groundwater contamination. Install the pump at a sufficient height above the bottom of the well to ...
 
... causing leaching of target analytes (NJDEP, 2005). In wells screened below the water table, set the pumping rate such that the water level is not drawn down into the screened section. ...
 
...table, set the pumping rate such that the water level is not drawn down into the screened section. Do not pump the well dry except ...
 
...Purging Low-Permeability Formations. Keep the pump rate low enough that the groundwater flow from the tube is laminar and does not induce turbulence in sampling containers. Choose ...
 
...check valve at the bottom and a means to attach a line to the top. The check valve allows water in to the interior chamber of the bailer as it is lowered into the saturated zone. When the ...
 
... the saturated zone. When the bailer is raised the check valve is forced shut and a water sample can be retrieved from the well. Larger diameter bailers may be used for well volume ...
 
... The purpose of bailer sampling is to collect samples representative of the groundwater at the sampling point. Therefore, bailer sampling must be preceded by well purging. ...
 
...documented to be less than 0.05 gallons per minute (200 milliliters per minute) and the water column in the well is less than 5 feet. Under these conditions, the "minimum-drawdown" purging ...
 
...a vacuum in an intake line drawing from the monitoring well. The vacuum draws groundwater up to the pump, where the water is dispensed from the end of the tubing. Tubing used for peristaltic ...
 
...up to the pump, where the water is dispensed from the end of the tubing. Tubing used for peristaltic pump sampling should be ...
 
...be proposed for use primarily if the following conditions exist: Depth to water is less than 15 to 20 feet There is limited recovery of water in a monitoring well ...
 
...is less than 15 to 20 feet There is limited recovery of water in a monitoring well Contaminants of concern do not include any on the previous list (USEPA, ...
 
... Office prior to field investigation. 6.5.6 Others Other groundwater samplers include passive diffusion samplers for VOCs or SVOCs, HydraSleeve®, the syringe ...
 
...be discussed with the HEER Office before use. 6.5.7 Order of Groundwater Sampling Collect samples in groundwater monitoring wells no sooner than 14 days after ...
 
...Sampling Collect samples in groundwater monitoring wells no sooner than 14 days after well development. This delay applies to newly ...
 

6.6 Filtration of Groundwater Samples
...Filter This filter type is typically used in the field collecting a filtered groundwater sample. An arrow on the body of the filter indicates the water flow direction when ...
 
... sample. An arrow on the body of the filter indicates the water flow direction when using the filter. [Source: Aqua Merik, 2008] ...
 
...filter. [Source: Aqua Merik, 2008] 6.6 FILTRATION OF GROUNDWATER SAMPLES Some contaminants and water quality parameters are impacted by excessive turbidity ...
 
...SAMPLES Some contaminants and water quality parameters are impacted by excessive turbidity in the water sample. Therefore, it is ...
 
...quality parameters are impacted by excessive turbidity in the water sample. Therefore, it is important to avoid introducing turbidity into the water samples since ...
 
...sample. Therefore, it is important to avoid introducing turbidity into the water samples since the HEER Office groundwater EALs are intended for comparison to dissolved phase ...
 
...samples since the HEER Office groundwater EALs are intended for comparison to dissolved phase contaminants (and not contaminants adsorbed ...
 
... low-flow purging and sampling technique is preferred, since it will not agitate the water column within the well. Bailer sampling should be avoided in cases where sediment has accumulated ...
 
... for sites near or adjoining the shoreline or in caprock substrate) filtering of groundwater samples prior to analysis for metals is generally accepted, and filtering for organic contaminants ...
 
... of the dissolved metal is dependent on the oxidation-reduction potential of the groundwater. In-situ groundwater is often under-saturated relative to the oxygen concentration in air. ...
 
...In-situ groundwater is often under-saturated relative to the oxygen concentration in air. Therefore, oxygen can ...
 
...to the oxygen concentration in air. Therefore, oxygen can dissolve from air into groundwater, resulting in an increased oxidation-reduction potential, which may change the oxidation ...
 
...and result in metal precipitation. It is therefore important to avoid aeration of groundwater collected for metals analysis. Aeration may occur during collection or transport. To ...
 
...results in a pH lower than 2, which keeps the dissolved metals in solution. A groundwater sample that is not filtered prior to preservation may yield false, elevated levels of dissolved-phase ...
 
...of an unfiltered sample may dissolve metals that are bound to particles suspended in the water sample. Therefore, a sample to be analyzed for dissolved metals must be filtered prior to preservation ...
 
... Due to the potential phase changes of metals that may occur during groundwater sampling and filtration, the HEER Office may require that analytical data for filtered samples ...
 
...samples be accompanied by data for unfiltered samples, especially at sites where groundwater is used as a water supply or may discharge into a nearby surface water body. ...
 
... is used as a water supply or may discharge into a nearby surface water body. 6.6.2 Filtering Procedures ...
 
...supply or may discharge into a nearby surface water body. 6.6.2 Filtering Procedures Filtration methods in the order ...
 
...An example of an in-line filter used in the field for the collection of a filtered water sample prior to preservation is illustrated in Figure 6-17. Filter the sample ...
 
...to 200 milliliters of sample to allow the filter to chemically equilibrate with the groundwater. Preserve the sample immediately upon filtration using proper preservation methods, in the ...
 

6.7 Aquifer Data Collection Methods
...of key characteristics used for evaluation of contaminant transport through groundwater. Hydraulic conductivity is a measure of the formation's ability to transmit water. It is therefore ...
 
...Hydraulic conductivity is a measure of the formation's ability to transmit water. It is therefore dependent on the permeability of the formation and the fluid properties. This ...
 
... describes methods to evaluate related characteristics of transmissivity, the average water transmission potential for a specific aquifer, and storativity or specific yield, the amount ...
 
...potential for a specific aquifer, and storativity or specific yield, the amount of water that a confined or unconfined aquifer will drain up for a certain change in hydraulic head. ...
 
... a certain change in hydraulic head. Hydraulic head is most commonly represented by groundwater elevation. Permeability of soil/rock samples can be determined in the laboratory and ...
 
...conductivity using the density and viscosity of the fluid being transmitted, in this case water or free phase product. However, soil/rock samples collected from soil borings may not ...
 
... are slug tests and pumping tests. Both tests require access to one or more groundwater monitoring well(s) on site. Ensure that the wells are properly developed and in equilibrium ...
 
...aquifer tests. On sites that are tidally influenced or show temporal groundwater fluctuations, monitor groundwater fluctuations in background wells throughout the duration ...
 
...fluctuations, monitor groundwater fluctuations in background wells throughout the duration of the aquifer test. The background ...
 
... in the test wells. Use the background monitoring data to correct for changes in the water table and potentiometric surface that are not related to the aquifer test. Methods are available ...
 
...also be required at sites with stratified aquifers or those sites where vertical groundwater movement is significant. The guidance presented below is adequate for porous formations. ...
 
... hydraulic conductivity in fractured rock requires a different approach, since the groundwater flow may be turbulent. The slug test assumes that the aquifer is confined. For pumping ...
 
...known volume (referred to as a "slug") from a well and continuously monitoring the groundwater level while the well recovers to its original level (Freeze et. al., 1979). Addition or ...
 
...used for evaluation of hydraulic conductivity. If the well screen extends above the water table, use a slug withdrawal procedure (Domenico et. al., 1990). Do not add water to a monitoring ...
 
...table, use a slug withdrawal procedure (Domenico et. al., 1990). Do not add water to a monitoring well at a contaminated site. A slug can be a solid cylinder or closed stainless ...
 
...to the bottom of the well. If a slug is to be removed from the well, insert it into the water column, wait until the water level has recovered to its original level and then remove it ...
 
...column, wait until the water level has recovered to its original level and then remove it as quickly as practicable. ...
 
... as quickly as practicable. In formations of high hydraulic conductivity, water level gauging must be continuous throughout the duration of the test. In this case, install ...
 
...a pressure transducer in the bottom of the well to log data continuously. Ensure that the water level has recovered to its original level after inserting the instrument prior to commencing ...
 
...with the downhole equipment. Accurately record the following: slug volume; water level within ±0.01 inch before, during and after the slug test; and the time of each ...
 
...within ±0.01 inch before, during and after the slug test; and the time of each water level measurement. There are several graphic/calculation methods to evaluate hydraulic ...
 
...packers separated by a length of perforated pipe. The test is then performed by inducing water into the isolated section. The procedure provides reliable data when performed properly ...
 
...procedure provides reliable data when performed properly (USEPA, 1992d). Do not introduce water into a monitoring well that extends into a contaminant plume. 6.7.2 Pumping ...
 
... 6.7.2 Pumping Tests An accurate method of determining the hydraulic properties of water-bearing substrate is the pumping test. Pumping tests tend to involve a comparatively larger ...
 
...change in hydraulic head is monitored, usually in terms of drawdown, or change in groundwater elevation in the aquifer in response to pumping and removal of water from the formation. The ...
 
...elevation in the aquifer in response to pumping and removal of water from the formation. The magnitude and rates of drawdown in the well, and rates of recovery ...
 
...Single Well Pumping Test Single well pumping tests involve the measurement of water levels over time in a single monitoring well at different rates of pumping. ...
 
... single monitoring well at different rates of pumping. Measure the original water level in the well. Then pump down the well for a period of time. Record the time when pumping ...
 
...when pumping stops. At the time when pumping stops, start monitoring the recovery of the water level in the well as a function of time (Domenico et. al., 1990). Storativity cannot ...
 
...relationship between the observation well and the pumping well, which stipulates that the water level change in the observation well, at a specified distance from the pumping well, is a function ...
 
...aquifer. Leakage may also arise through other sources such as connected bodies of surface water etc. In general, the first part of the drawdown will resemble that of a confined aquifer until ...
 
...(Domenico et. al., 1990). Unconfined Aquifers: When water is withdrawn from confined aquifers, the aquifer does not undergo dewatering, unless the groundwater ...
 
...is withdrawn from confined aquifers, the aquifer does not undergo dewatering, unless the groundwater elevation/head is lowered below the confining layer. The ...
 
... unless the groundwater elevation/head is lowered below the confining layer. The water is released from storage through ...
 
...elevation/head is lowered below the confining layer. The water is released from storage through elastic compression of the matrix and expansion of the water. ...
 
...is released from storage through elastic compression of the matrix and expansion of the water. In unconfined aquifers lowering of water levels actually causes some dewatering of the aquifer ...
 
...In unconfined aquifers lowering of water levels actually causes some dewatering of the aquifer and the value of storativity increases ...
 
...levels actually causes some dewatering of the aquifer and the value of storativity increases by several orders of magnitude. In ...
 
...as assumed by the Theis equation. Another assumption of the Theis equation is that water is instantaneously released from storage with decline in head. If this does not hold true, ...
 

6.8 Groundwater Modeling
... ' 6.8 GROUNDWATER MODELING The purpose of groundwater modeling is to generate a visual representation of ...
 
...MODELING The purpose of groundwater modeling is to generate a visual representation of an aquifer including the overall groundwater ...
 
...modeling is to generate a visual representation of an aquifer including the overall groundwater movement, and in the case of contaminated sites, the fate and transport of contaminants. Groundwater ...
 
...and in the case of contaminated sites, the fate and transport of contaminants. Groundwater modeling is also used to predict contaminant plume movement into the future or to predict the ...
 
...or to predict the aquifer and plume response to remedial activities. Groundwater modeling may be done manually by using a calculator or spreadsheet and then creating a graphical ...
 
...and then creating a graphical depiction of the data using flow nets. Manual groundwater modeling methods may be useful for creating preliminary site conceptual models intended ...
 
...and the initial contaminant plume extent. However, if the purpose of groundwater modeling is to predict how a contaminant plume changes over time or how it will respond to ...
 
...is to predict how a contaminant plume changes over time or how it will respond to water pumping or remedial activities, modeling becomes computationally intensive, and a computer ...
 
...in the design of sampling strategies during site monitoring and in the design of groundwater remediation systems. Computer groundwater models are based on the geologic and hydrologic field ...
 
...remediation systems. Computer groundwater models are based on the geologic and hydrologic field data collected during drilling, geotechnical ...
 
...Gradient and Flow Direction Determination The simplest way to determine the groundwater gradient and flow direction is by graphically constructing a flow net for the site. A flow ...
 
...lines connect points of equal head and the flow lines depict the interpreted groundwater flow path or flow direction. To construct a flow net for a site, measure the ...
 
...net for a site, measure the hydraulic head in wells across the site following the groundwater gauging procedures detailed previously in this section. Enter the measurements onto a site ...
 
...between adjacent lines is constant. The equipotential lines represent the height of the water table or potentiometric surface above mean sea level or other datum plane. Add ...
 
...mean sea level or other datum plane. Add flow lines to depict the movement of groundwater at the site. Groundwater follows the path of steepest groundwater gradient. At a site where ...
 
...at the site. Groundwater follows the path of steepest groundwater gradient. At a site where the aquifer formation ...
 
...follows the path of steepest groundwater gradient. At a site where the aquifer formation is isotropic and porous, the steepest groundwater ...
 
...At a site where the aquifer formation is isotropic and porous, the steepest groundwater gradient is the shortest path between equipotential lines. The shortest path is perpendicular ...
 
...such that the flow is equally divided between adjacent lines. Calculate the groundwater gradient as follows: Measure the distance between two equipotential lines along a flow line, ...
 
...between the equipotential lines. Divide the head loss by the distance. The groundwater flow direction is along the flow lines. Depict flow lines as arrows pointing in the direction ...
 
...is along the flow lines. Depict flow lines as arrows pointing in the direction of groundwater flow, i.e., in the direction of declining hydraulic head. 6.8.2 Velocity, ...
 
...in Subsection 6.7, Aquifer Data Collection Methods. Calculate the groundwater velocity (v) using the following equation: v = q/ne = (K dh/dl) / ne ...
 
... v = q/ne = (K dh/dl) / ne Where: v = actual groundwater velocity q = Darcy velocity ne = effective porosity (connected ...
 
...velocity ne = effective porosity (connected pore space through which groundwater can flow) K = Hydraulic conductivity dh/dl = groundwater ...
 
...can flow) K = Hydraulic conductivity dh/dl = groundwater gradient (change in groundwater elevation in two wells over distance between the wells) ...
 
...gradient (change in groundwater elevation in two wells over distance between the wells) Compare the ...
 
...over distance between the wells) Compare the calculated groundwater velocity to the velocity range expected based on aquifer lithology. Note that ...
 
...many consequences. For example, in a hydraulically isotropic, porous formation, the groundwater flow direction is perpendicular to the equipotential lines of the water table/potentiometric ...
 
...flow direction is perpendicular to the equipotential lines of the water table/potentiometric map. This assumption cannot be made in a fractured formation, since the ...
 
...of fractured rock with an equivalent hydraulic conductivity of K will conduct as much water as one square meter of porous medium with a hydraulic conductivity of K, under identical hydraulic ...
 
...be used at a site for many different goals including: (1) estimating how the actual groundwater system functions; (2) selecting sampling approaches, objectives and locations; (3) predicting ...
 
...are relatively more simplistic, offer an inexpensive method to conduct preliminary groundwater analysis, and may be useful during the early phases of a project. Numerical approaches are ...
 
...and software. However, numerical approaches easily deal with variability in the groundwater flow and contaminant transport parameters, which provides flexibility in representing complex ...
 
...solutions and for the evaluation of environmental hazards. A groundwater modeling report should, at a minimum, include (USEPA, 1992a): Previous studies ...
 

6.9 Surface Water Sample Collection Methods
... [Source: USGS, 2008b] 6.9 SURFACE WATER SAMPLE COLLECTION METHODS Environmental investigation sites featuring adjoining surface ...
 
...COLLECTION METHODS Environmental investigation sites featuring adjoining surface water bodies may require the collection of surface water samples to assess environmental impacts. ...
 
...bodies may require the collection of surface water samples to assess environmental impacts. Select the sampling approach and sampling equipment ...
 
...impacts. Select the sampling approach and sampling equipment based on the type of surface water (flowing versus still), the sampling platform and the contaminant characteristics. ...
 
...and the contaminant characteristics. 6.9.1 Sampling Flowing and Still Surface Waters In general, an isokinetic water sampler is used to collect a sample from water flowing ...
 
... In general, an isokinetic water sampler is used to collect a sample from water flowing faster than 1.5 to 2 feet per second. ...
 
...sampler is used to collect a sample from water flowing faster than 1.5 to 2 feet per second. Non-isokinetic water samplers are used for ...
 
...flowing faster than 1.5 to 2 feet per second. Non-isokinetic water samplers are used for all other surface water sampling applications. In flowing ...
 
...samplers are used for all other surface water sampling applications. In flowing water, always position the sampler upstream of any ...
 
...sampling applications. In flowing water, always position the sampler upstream of any disturbance caused by sampling activities. In ...
 
...the sampler upstream of any disturbance caused by sampling activities. In standing water deploy the sampler away from any disturbance caused by sampling. Avoid contact of sampling ...
 
...sampler. Refer to United States Geological Survey (USGS) document entitled "Handbooks for Water-Resources Investigations - National Field Manual for the Collection of Water-Quality Data" ...
 
...Investigations - National Field Manual for the Collection of Water-Quality Data" for more information on isokinetic samplers (USGS, 2002). ...
 
... 2002). Use an isokinetic sampler to collect a depth integrated, representative water sample continuously and isokinetically (that is, stream water approaching and entering ...
 
...sample continuously and isokinetically (that is, stream water approaching and entering the sampler intake does not change in velocity) from a vertical section ...
 
... Laboratory Cleaned Bottles The most widely used method for collection of surface water samples is simple immersion of the laboratory cleaned sample bottle below the surface of a ...
 
...simple immersion of the laboratory cleaned sample bottle below the surface of a surface water body. This method eliminates the need for other equipment and reduces the risk of introducing ...
 
...other variables into a sampling event. Immerse the open bottle by hand into surface water and allow water to slowly run into the bottle minimizing turbulence. Collect samples for volatile ...
 
...and allow water to slowly run into the bottle minimizing turbulence. Collect samples for volatile organics ...
 
...volatile organics analysis first to prevent loss of volatiles due to disturbance of the water. Do not disturb the sediment, especially when analytes (such as metals) could be impacted by ...
 
... Transfer the sample slowly into a laboratory supplied sample bottle, allowing the water to flow gently down the inside of the bottle. Avoid turbulence in the sample stream. Always ...
 
...and transfer the sample slowly into a laboratory supplied sample bottle, allowing the water to flow gently down the inside of the bottle. Avoid turbulence in the sample stream. Always ...
 
...sampling depth. Use the Wheaton Dip Sampler to collect samples in shallow surface water. With the bottle cap closed, lower the sampler to the required depth and unscrew the bottle ...
 
...unscrew the bottle cap. Once the bottle is filled, (i.e. when no more bubbles reach the water surface) screw the bottle cap back on and retrieve the bottle. Transfer the ...
 
... Transfer the sample slowly into a laboratory supplied sample bottle, allowing the water to flow gently down the inside of the bottle. Avoid turbulence in the sample stream. Always ...
 
... Sampler shown with the end stoppers open (left) prior to immersion in the surface water body and closed (right) following sample collection. [Source: General Oceanics, 2008] ...
 
... The Van Dorn sampler and Niskin bottle sampler are cylindrical samplers closed with water-tight stoppers on both ends. The stoppers are connected through an elastic band that runs through ...
 
...to the outside of the cylinder, leaving both pipe openings unobstructed, which allows for water to enter the cylinder. After the sampler has been placed at the pre-determined sampling depth, ...
 
...band pulls the stoppers into their seat and maintains the closed position to create a water-tight seal. A valve at the bottom of the cylinder together with a vent at the top are ...
 
...from the sampler drain valve into a laboratory supplied sample bottle, allowing the water to flow gently down the inside of the bottle. Avoid turbulence in the sample stream. ...
 
... The VOC sampler has been manufactured for the USGS and is used to collect open water samples for volatile organic compound analysis. The device has been tested in the ...
 
...lid into the bottom of the vials (Figure 6-20). When the sampler is lowered into water, the vials start to fill. The vials overflow into the inside of the cylinder, which has sufficient ...
 
... both ends. Both check valves are designed to open as the bailer is lowered into water and to close when it is retrieved. Dedicate the bailer to one sample location, when feasible. ...
 
...from the sampler drain valve into a laboratory supplied sample bottle, allowing the water to flow gently down the inside of the bottle. Avoid turbulence in the sample stream. Always ...
 
... first. Use a bottom emptying device with flow control when the bailer is used to collect water for volatile analysis. 6.9.2 Composite Sampling Use composite sampling ...
 
... 6.9.2 Composite Sampling Use composite sampling to represent a cross section of a water body. Composite samples vertically over the depth of a water body in one location or horizontally ...
 
...body. Composite samples vertically over the depth of a water body in one location or horizontally along a specific water depth. Use an isokinetic ...
 
...body in one location or horizontally along a specific water depth. Use an isokinetic sampler to collect a depth integrated, representative water ...
 
...depth. Use an isokinetic sampler to collect a depth integrated, representative water sample continuously and isokinetically (that is, stream water approaching and entering ...
 
...sample continuously and isokinetically (that is, stream water approaching and entering the sampler intake does not change in velocity) from a vertical section ...
 
...described below. For horizontal cross sections, collect discrete samples along one water depth traversing a body of water. Determine the total water volume needed to ...
 
...depth traversing a body of water. Determine the total water volume needed to fill all the sample bottles and add at ...
 
... Determine the total water volume needed to fill all the sample bottles and add at least 10% for filter losses etc. Select ...
 
...or pond, sample the verticals or horizontals as often as required to collect a sufficient water volume. Ensure that all verticals or horizontals are sampled the same number of times. ...
 
...with a churning paddle and a drain valve. Use a churn splitter to composite surface water samples. Always collect a minimum of 3 liters of water volume for a composite sample when ...
 
...samples. Always collect a minimum of 3 liters of water volume for a composite sample when using the churn splitter. Note that a churn splitter does ...
 
...splitter. Note that a churn splitter does not reliably produce representative composited water samples when it contains less than 2 liters. Prior to use, decontaminate the churn splitter ...
 
...site contaminants. Prior to sampling, rinse the churn three times with 1 liter of sample water each. Let the sample water drain from the drain valve each time. This will allow the container ...
 
...each. Let the sample water drain from the drain valve each time. This will allow the container to chemically equilibrate ...
 
...valve each time. This will allow the container to chemically equilibrate with the sample water. Collect the required number of sub-samples and add to the churn. Keep the churn ...
 
...churn. Keep the churn closed at all times except when adding sub-samples. Composite the water samples by moving the paddle up and down at least 10 times achieving a churning rate of ...
 
...at least 10 times achieving a churning rate of 9 inches per second before withdrawing water (NJDEP, 2005). Faster or slower churning rates can cause maximum errors of 45% to 65%. The ...
 
...be sustained throughout sample withdrawal. Increase the round trip frequency as the water volume in the splitter decreases so that the churning disc velocity is constant. The disc should ...
 
...touch bottom, and every stroke length should be as long as possible without breaking the water surface. Increase of the stroke length and/or disc velocity beyond the recommended rate will ...
 
...Once all sample bottles have been filled, rinse the churn thoroughly with deionized water, allowing the rinse water to flow through the drain valve. Keep the churn lid closed at all ...
 
...allowing the rinse water to flow through the drain valve. Keep the churn lid closed at all times to avoid contamination ...
 
...Lower the sampler to the target depth and trigger the closing mechanism. In shallow water collect the sample by submerging the closed sample containers by hand to the desired depth. ...
 
...remains at the sampling depth. Once the lid is in place remove the container from the water. 6.9.5 Lake/Standing Water Sampling Collect water from lakes and ...
 
... 6.9.5 Lake/Standing Water Sampling Collect water from lakes and other standing water as point samples. Either composite ...
 
...Sampling Collect water from lakes and other standing water as point samples. Either composite the point samples or ...
 
...from lakes and other standing water as point samples. Either composite the point samples or keep them as discrete samples as required ...
 
...point samples or keep them as discrete samples as required in the SAP. Collect surface water samples at a depth of one meter. If the water is shallower than one meter, collect the sample ...
 
...samples at a depth of one meter. If the water is shallower than one meter, collect the sample from just below the water surface or at mid-depth. ...
 
...is shallower than one meter, collect the sample from just below the water surface or at mid-depth. Sampling events should also be conducted during subsequent seasons, ...
 
...with sampling activities such as a boat or wading or sampler deployment. Calm waters will possibly help keep a lake's stratification more observable and make sampling each observable ...
 
... the procedure recommended by the USEPA in its publication entitled: "Sampling Ambient Water for Trace Metals at EPA Water Quality Criteria Levels" (USEPA, 1996d). ...
 
...for Trace Metals at EPA Water Quality Criteria Levels" (USEPA, 1996d). 6.9.8 Filtration ...
 
...(USEPA, 1996d). 6.9.8 Filtration For surface water filtration follow the same procedures outlined for groundwater filtration of groundwater samples ...
 
...filtration follow the same procedures outlined for groundwater filtration of groundwater samples (Subsection 6.6, Filtration). ...
 
... filtration of groundwater samples (Subsection 6.6, Filtration). ...
 

6.10 Investigation Derived Waste
...(IDW) generated during monitoring well installation, well development, well purging, and water sample collection activities. Contain all IDW in approved containers conforming to the requirements ...
 

Contents
... 7.10.5.2 Water Dam Vapor Point Test   ...
 
... 7-29 Example PVC Coupling "Water Dam" Sealed to Floor with Inert Putty for Leak Testing Slab-mounted Vapor Point ...
 

7.0 Soil Vapor and Indoor Air Sampling Guidance
...risks posed to outdoor air and overlying buildings. The development of HDOH soil, groundwater and soil gas (�vapors�) action levels for evaluation of vapor intrusion hazards is described ...
 
...Evaluation of Environmental Hazards at Sites with Contaminated Soil and Groundwater (�EHE guidance;� HDOH 2011, see also PBEHE 2012). The discussion provided below and ...
 

Figures
... 7-29 Example PVC Coupling "Water Dam" Sealed to Floor with Inert Putty for Leak Testing Slab-mounted Vapor Point. ...
 

7.1 Soil Vapor Transport Mechanisms and Conceptual Models
...tanks. The emission of volatile chemicals from contaminated soil and groundwater can create a plume of vapors in the vadose zone. These plumes can adversely impact indoor air ...
 
...(see HDOH 2011). Vapors in vadose-zone soil could also migrate downwards and impact groundwater that has otherwise not been directly affected by the release. This has been recognized, for ...
 
...with the presence of relatively shallow, free product in vadose-zone soil or groundwater (see USEPA 2013). Under most site scenarios, the breakdown of petroleum compounds ...
 
...potential vapor intrusion concerns even in the absence of free product in soil or groundwater. Dilute plumes of solvent-contaminated groundwater have, for example, been documented to travel ...
 
...Dilute plumes of solvent-contaminated groundwater have, for example, been documented to travel thousands of feet downgradient of initial release ...
 
...an earlier period of operation. The presence of high levels of vinyl chloride in groundwater or soil vapor at sites often indicates the presence of co-located petroleum contamination. ...
 
...of petroleum. The presence of significant breakdown products in soil vapor or groundwater signifies the need to look for petroleum contamination in the same area. ...
 

7.2 Soil Vapor Intrusion to Indoor Air
... areas (Figure 7-1). Vapors diffuse much more rapidly through air-filled pore space than water-filled pore space. Advective flow of vapors caused by pressure differentials (e.g., flow from ...
 
...include the �wet� season during the winter, and the �dry� season during the summer. The water table rises and falls accordingly. The magnitude of this rise and fall is minimal in coastal ...
 
...rise and fall is minimal in coastal areas near sea level. In inland areas the seasonal water table fluctuation can reach ten feet or more, however. The rise and fall of the water table ...
 
...table fluctuation can reach ten feet or more, however. The rise and fall of the water table can create a smear zone of contaminated soil of equal magnitude, especially in the case ...
 
...of equal magnitude, especially in the case of petroleum releases that have reached groundwater. As the water table falls and exposes this smear zone, an increase in vapor emissions can occur. ...
 
...As the water table falls and exposes this smear zone, an increase in vapor emissions can occur. As the water ...
 
...table falls and exposes this smear zone, an increase in vapor emissions can occur. As the water table rises some product may rise with it and continue to pose vapor emission hazards. A substantial ...
 
...hazards. A substantial portion is likely to remain trapped in the smear zone below the water table, however. This can result in a substantial reduction in vapor emissions during the wet ...
 
...dramatically over the year (see Section 7.10.1). The rise and fall of the water table with fluctuating tides could also influence the migration of vapors in the vadose zone. ...
 
...zone. Indoor air could be pulled out of the building and into the subslab zone as the water table falls. The same air, or a mixture of this air and VOCs from subsurface contamination, ...
 
...air and VOCs from subsurface contamination, could be pushed back into the building as the water table rises if the building was not over-pressured. This phenomenon has not been studied in ...
 
...has not been studied in detail in Hawai�i. Small, tide-related fluctuations of the water table observed in coastal areas of Hawai�i, typically less than one-foot, are unlikely to cause ...
 
...The collection of subslab soil vapor samples during periods of both falling and rising water table may be recommended or required, however, at sites that overlie significant, shallow ...
 
...on the expected subsurface geology, depth to the potential source contaminants or groundwater, and actual or potential human or environmental receptors, as well as other specific information ...
 
...e.g., benzene and PCE). A focus on soil vapor samples collected during periods of high water table or vapor flux assumptions during periods when a building is over-pressurized can lead ...
 
...vapor intrusion hazards. A focus on subsurface data collected during periods of low water table or periods when the building is under-pressured and most susceptible to vapor intrusion ...
 
...includes the outward diffusion of vapor-phase chemicals from impacted soil or groundwater and the potential advective flow of the vapors into an overlying building (Figure 7 1). ...
 
...with petroleum hydrocarbon or volatile organic compounds (VOC) impacted soil and groundwater (Figure 7-2). The biodegradation processes include aerobic and anaerobic degradation of contaminants ...
 

7.3 Characterization, Delineation and Monitoring
...action levels for rapid screening of suspect sites. Development of the HDOH soil, groundwater and soil gas (�vapor�) action levels for vapor intrusion is discussed in the HDOH EHE guidance ...
 

7.4 Soil Vapor Probe Installation
...are collected following the discovery or identification of subsurface soil or groundwater contamination containing volatile or semi-volatile constituents. In addition to the evaluation ...
 
...out in a manner that minimizes stripping of VOCs from free product in soil or groundwater or stripping of VOCs otherwise sorbed to soil particles or dissolved in groundwater and not ...
 
...or stripping of VOCs otherwise sorbed to soil particles or dissolved in groundwater and not initially present in the vapor phase. This is accomplished primarily by minimizing ...
 
...additional stripping of VOCs in product, sorbed to soil particles or dissolved in groundwater. HDOH is currently studying approaches for the collection of representative and ...
 

7.6 Soil Vapor Sample Collection Procedures
...are collected to help locate and characterize areas of contaminated soil and groundwater that might require remediation or long-term management. The direct collection of groundwater ...
 
...that might require remediation or long-term management. The direct collection of groundwater samples is generally adequate to identify contamination with volatile chemicals. This is because ...
 
...tends to become dispersed over relatively large areas due to diffusion and groundwater flow. The additional collection of soil vapor samples to assist in the identification ...
 
...of soil vapor samples to assist in the identification of areas of contaminated groundwater is typically not necessary or required. Note, however, that groundwater action ...
 
...is typically not necessary or required. Note, however, that groundwater action levels presented in the HDOH EHE guidance are not applicable for sites where the depth ...
 
...presented in the HDOH EHE guidance are not applicable for sites where the depth to groundwater is less than ten feet due to limitations in the models and data used to develop the levels. ...
 
...be considered. Direct collection of soil vapor samples regardless of soil and/or groundwater data is also recommended for sites with a very high potential for the release of volatile chemicals. ...
 
...and dry cleaners (see Section 7.6.2.2). As is the case for groundwater, volatile chemicals in subsurface soils tend to more evenly disperse over relatively large ...
 
... for the initial evaluation of vapor intrusion hazards at sites where soil or groundwater is contaminated with volatile chemicals (HDOH 2011): ...
 
... Contaminants in Vadose Zone 2Soil and/or 3Groundwater Pose Potential Vapor Intrusion Hazards ...
 
...(e.g., PCE vapors under a dry cleaner). Free product on groundwater table or dissolved VOC concentrations above Tier 1 groundwater action levels for vapor ...
 
...table or dissolved VOC concentrations above Tier 1 groundwater action levels for vapor intrusion. VOC concentrations ...
 
... VOC concentrations below Tier 1 EALs for both soil or groundwater and significant volume (e.g., >10m3) of VOC-contaminated soil or other potential ...
 
... vapors under a building slab not suspected. Compare groundwater and soil analytical data to appropriate HDOH environmental action levels (EALs) ...
 
...in Evaluation of Environmental Hazards at Sites with Contaminated Soil and Groundwater (HDOH 2011) or site-specific action levels approved by HDOH. See Table C-1a for Groundwater ...
 
...(HDOH 2011) or site-specific action levels approved by HDOH. See Table C-1a for Groundwater Action Levels and Table C-1b for Soil Action Levels, located in Appendix 1 of the EHE document; ...
 
...results to Shallow Soil Gas Action Levels for areas over or near a plume where Groundwater and/or Soil EALs for vapor intrusion are approached or exceeded or sites where a potentially ...
 
...sampling is recommended (Step 2) based on the occurrence of VOCs in soil and/or groundwater and the distance between the building and the source area. The initial ...
 
... that significantly impede the upward diffusion of vapors (diffusion rates through water are typically four orders-of-magnitude slower than through soil; see Appendix 1 in HEER EHE ...
 
...see Appendix 1 in HEER EHE guidance, HDOH 2011). Thin lenses of perched groundwater can further reduce upward vapor flux. Aerobic biodegradation of non-chlorinated, vapor-phase, ...
 
...a few feet of a source area (e.g., heavily contaminated soil or free product on groundwater). A discussion of targeted chemicals of concern for petroleum releases is provided ...
 
...or concentration of petroleum in underlying soil or the presence of free product on groundwater (e.g., Abreu et. al 2009, McHugh 2010; USEPA 2013). For dissolved-phase contaminants a �vertical ...
 
...intrusion hazards can be ruled out without the collection of soil gas samples. If the water table is at a depth of greater than fifteen feet year round and no free product is present ...
 
...a depth of greater than fifteen feet year round and no free product is present on groundwater and contaminated soil is not present in the vadose zone, then potential vapor intrusion hazards ...
 
...hazards are unlikely to be posed by dissolved-phase petroleum contaminants in groundwater under any site scenario due to low source strength and rapid biodegradation of vapors ...
 
...Large volumes of shallow, contaminated soil or widespread free product on shallow groundwater (i.e., <30ft deep) could lead to the accumulation of vapors under caps and a progressive ...
 
...exceptions include substantial subsurface releases of petroleum in areas with a very deep water table (e.g., >50ft). This could lead to the presence of a thick, deep column of heavily ...
 
... deep (i.e., >30ft) widespread, heavily contaminated soil or free product on groundwater. Such scenarios could be possible with large releases from fuel pipelines, fuel hydrant ...
 
...in the HEER guidance Long-Term Management of Petroleum-Contaminated Soil and Groundwater HDOH 2007c). 7.6.2 Soil Vapor Sampling Design ...
 
...sampling strategy depends on site-specific conditions, including soil types and groundwater levels, the number and size of existing buildings, and current site use or future development ...
 
...of the source area because soil vapor can migrate in a different direction than groundwater flow. When assessing upward, vertical migration, vapor samples from multiple depths may be ...
 
...7-4: Schematic of Soil Vapor Concentration Profile. VOCs volatilize out of a groundwater plume and diffuse vertically toward the surface. Vapor phase concentrations are highest ...
 
...vertically toward the surface. Vapor phase concentrations are highest at the groundwater-vadose zone interface and decrease with decreasing depth. Vapors can accumulate under buildings ...
 
...might not mimic the shape of the primary source area (i.e., contaminated soil or groundwater). This is because the outward, lateral migration of vapors away from the source area is strongly ...
 
...of five to ten feet below ground surface (or no more than two to three feet above groundwater for shallow water tables) in order to take into consideration the potential buildup of vapors ...
 
...for shallow water tables) in order to take into consideration the potential buildup of vapors under existing ...
 
...of time in the vadose zone following active, in situ remediation of contaminated groundwater (�residual vapor plume,� see Table 7-1). The San Diego County Site Assessment and ...
 
...as the nature and magnitude of the release, the subsurface geology and the depth to groundwater. The investigation of potential vapor intrusion hazards will require the placement of sample ...
 
...the distance to the source area is 5 feet or greater, but no closer than 2-3 ft to the water table to avoid pulling water into the sample collection device (see Figure 7-4; see also ...
 
...table to avoid pulling water into the sample collection device (see Figure 7-4; see also Sections 7.9.3 and ...
 
...ten feet for petroleum-contaminated sites or no more than two to three feet above groundwater for sites with a shallow water table. This is necessary in order to take into consideration ...
 
...for sites with a shallow water table. This is necessary in order to take into consideration the potential buildup of vapors ...
 
...point. Three or more sample depths may be beneficial at sites with deep sources or water tables. The site geology should also be considered when identifying sampling depths. ...
 
...above the maximum-anticipated, seasonally- or tidally-influenced elevation of the water table. 7.6.2.4 Soil Vapor Sample Screen Intervals Soil ...
 
...conditions. Note that the same is true with respect to the representativeness of a groundwater sample collected from a five-foot, monitoring well screen or from a much smaller interval ...
 

7.7 Indoor Air Sample Collection Procedures
...vapors is present below the building (e.g., petroleum free product on shallow groundwater) then the collection of source area soil vapor samples is also recommended (see ...
 

7.8 Soil Vapor or Indoor Air Sample Analysis
...of soil vapor or indoor air samples can be more involved and complex than soil or groundwater sample collection. This is due in part to the need for special sampling equipment and containers ...
 
...these approaches is provided in Table 7-3. Similar to soil and groundwater sample collection, a combination of sampling approaches can be used if analyzing for a broad ...
 
... Water ...
 
... Do not chill samples during storage as is common with soil and water samples. Sample containers should not be left in the direct sunlight. ...
 
... (e.g., to evaluate TPH in vapors associated with diesel-contaminated soil or groundwater) and the volume of vapors to be drawn is less than one liter then the concurrent collection ...
 
...a screening tool for soil vapor investigations. An emerging exception could be the use of water-based passive samples, discussed in a following section. Implementation of passive ...
 
... and Development for soil vapor characterization (Paul 2009). This sampler uses water as the media into which contaminants partition rather than the solid adsorbent approach described ...
 
... The PDS is constructed using a 40 ml VOA vial filled with de-ionized water and with the Teflon septa replaced with a vapor-permeable membrane. The PDS is inserted into ...
 
...exposed to the screened interval and contaminants diffuse through the membrane into the water-filled PDS until the water reaches equilibrium with the surrounding soil vapor. The PDS ...
 
... PDS until the water reaches equilibrium with the surrounding soil vapor. The PDS is recovered from the well after ...
 
...PDS sample after collection should be considered in the similar manner as done for groundwater samples (see Section 6). The water is then analyzed for targeted VOCs, with results ...
 
...samples (see Section 6). The water is then analyzed for targeted VOCs, with results expressed in units of mass per volume of water ...
 
...is then analyzed for targeted VOCs, with results expressed in units of mass per volume of water (e.g., ug/L). The concentration of the VOC in water is then multiplied by the Henry’s Law constant ...
 
...(e.g., ug/L). The concentration of the VOC in water is then multiplied by the Henry’s Law constant for that chemical to estimate the average, equilibrium ...
 

7.9 Gas Phase Sample Evaluation
... 7.9.2 Permanent Probes Permanent probes are constructed similar to groundwater monitoring wells installed using auger or direct push drilling techniques. However, permanent ...
 
...probe using a hand auger. Permanent probes should be finished to preclude infiltration of water or the exchange of ambient air in the sample tubing. Surface completions of permanent ...
 
...is poured to the top of the 3/4-inch hole and hydrated. Care should be taken not to allow water to leak into the filter pack sand. The Swagelok fitting is then sealed in place ...
 
... to help seal the annular space around a point. A small amount of water can be added to holes drilled in slabs (“wet drilling”) if high levels of methane or other ...
 

7.10 Documentation of Soil Vapor or Indoor Air Sampling
... Figure 7-29: Example PVC Coupling "Water Dam" Sealed to Floor with Inert Putty for Leak Testing Slab-mounted Vapor Point. After ...
 
...for Leak Testing Slab-mounted Vapor Point. After Cox-Colvin 2013, b. The water level is filled to a level above the tubing connection to the vapor point and monitored ...
 
...the distance to the source area is greater than 5 feet (but no closer than 2-3 ft to the water table) and a potentially significant source is present (see Section 7.6.2.3). This will help ...
 
... include building HVAC system operation, seasonal weather variations and associated water table fluctuations and tidal effects on groundwater elevation. Multiple sampling events are ...
 
...table fluctuations and tidal effects on groundwater elevation. Multiple sampling events are recommended if the conceptual model identifies the ...
 
...for sites where a significant smear zone is known or suspected to be present at the water table and exposure of contaminated soil in the smear zone could vary dramatically ...
 
...considered at sites where a substantial smear zone that could be exposed during falling water tables is known or suspected to be present. The collection of subslab soil vapor samples during ...
 
...The collection of subslab soil vapor samples during periods of both falling and rising water table may be necessary on a site-specific basis to evaluate the effects of tidal pumping on ...
 
...concentrations at high-risk, coastal sites with significant free product on shallow groundwater. At sites near the coast, the tides can affect groundwater levels, soil vapor samples ...
 
... At sites near the coast, the tides can affect groundwater levels, soil vapor samples should be collected at the same point in the tidal cycle in order ...
 
...collection of subslab samples during both rising and falling tides (or more specifically water tables) may also be necessarily, especially if significant concentrations of vapor-phase contaminants ...
 
...not including capillary fringe zone soils), 2) Less than 30m2 area of floating product on water table present, 3) Larger area of floating product present but greater than 30-foot vertical ...
 
...floating product present but greater than 30-foot vertical separation distance, and/or 4) Water table fluctuations unlikely to expose a smear zone greater than three feet thick within 30 ...
 
... of one round of samples should be collected at chlorinated solvent sites where groundwater action levels are approached or exceeded or a significant source is present in the ...
 
...Sites with widespread, heavy contamination in vadose-zone soil and/or floating on groundwater within 30 vertical feet or 100 lateral feet of a building slab that do not meet the above-noted ...
 
...should not be collected (e.g., vacuum greater than seven inches Hg or 100 inches of water; see Section 7.10.3.2). In addition to potential short circuiting to the surface, imposition ...
 
...intended to keep the vacuum imposed on the soil to below seven inches Hg (100 inches of water) and avoid migration of otherwise sorbed VOCs into the air-filled pore space (see following ...
 
...purging and sample collection vacuum should be less than seven inches Hg (100 inches of water; SDC 2011, CalEPA 2012). Increasing the vacuum on the sampling system (e.g., resulting ...
 
...in the sampling probes increases. High vacuums for sample points within a few feet of the water table can also cause water to be pulled into the sample container. This not only causes potential ...
 
...table can also cause water to be pulled into the sample container. This not only causes potential problems for the laboratory, ...
 
...the integrity of the sample data since vapor-phase compounds could partition into the water during storage and shipment of the sample. If water is drawn into a sample container then the ...
 
...during storage and shipment of the sample. If water is drawn into a sample container then the sample should be recollected (preferred) ...
 
...1) A �shut-in� test to determine the tightness of the sampling train in the field, 2) A �water dam� test for field testing of the integrity of the vapor point when installed into a slab ...
 
...this allows the tightness of the sampling train to be quickly evaluated in the field. A water dam test, as described below, or equivalent test is recommended for vapor points installed ...
 
...should still be placed around the point. A combination of a field shut-in test with a water dam (for intact slabs) and/or the Method 1 tracer test described above will be adequate for ...
 
... should be rechecked and the shut-in test repeated. 7.10.5.2 Water Dam Vapor Point Test A �water dam� offers a simple and inexpensive method to test ...
 
...Dam Vapor Point Test A �water dam� offers a simple and inexpensive method to test for leaks around vapor points installed ...
 
...surface (e.g., see Cox-Colvin 2013b). For a flush-mount installation, water is poured directly into the depression cut into the floor around the vapor point (see Figure ...
 
...a coupling can be sealed to the floor around with non-volatile putty and then filled with water (Figure 7-29). Pour enough distilled water into the water dam containment or the ...
 
...(Figure 7-29). Pour enough distilled water into the water dam containment or the annular space of a flush-mount depression to immerse ...
 
...into the water dam containment or the annular space of a flush-mount depression to immerse the tubing connection ...
 
...a flush-mount depression to immerse the tubing connection to the vapor point. Note that water soluble clays such as Play-Doh might absorb too much water to be suitable for tests that last ...
 
...soluble clays such as Play-Doh might absorb too much water to be suitable for tests that last more than one hour. Assemble the sample train and connect ...
 
...0.5 in Hg loss of vacuum (see previous section). Purge the vapor point and monitor the water level in the dam. The water level might drop slightly due to absorption into the concrete. ...
 
...level in the dam. The water level might drop slightly due to absorption into the concrete. A sudden drop in water level, ...
 
...level might drop slightly due to absorption into the concrete. A sudden drop in water level, the appearance of water in sample tubing or other indication of water entering the sub-slab ...
 
...level, the appearance of water in sample tubing or other indication of water entering the sub-slab is most likely indicative ...
 
...in sample tubing or other indication of water entering the sub-slab is most likely indicative of a significant leak, however. If this occurs ...
 
...indicative of a significant leak, however. If this occurs then remove the distilled water and reposition or reseal the vapor point to address the leak. 7.10.5.3 ...
 
...of Play-Doh to seal the base of the shroud. Play-Doh is a non-toxic mixture of flour, water, salt, boric acid and mineral oil. Volatile chemicals associated with the mineral oil are negligible ...
 

7.0 Soil Vapor and Indoor Air Sampling Guidance
...Screening for Environmental Hazards at Sites with Contaminated Soil and Groundwater (Environmental Hazard Evaluation [EHE] guidance [HDOH 2011]). In the EHE guidance, ...
 

9.1 Pesticide Contamination at Former Agricultural Facilities and Sites
...could also pose leaching hazards and subsequent contamination of underlying groundwater resources (e.g., triazine pesticides and fumigants). This generally requires that the full ...
 
...four to fourteen inches below ground surface. DBCP and EDB have been detected in groundwater wells on Oahu and Maui and have not been used since the mid-1980s (HDOH 1985, ...
 
...(TCP) is an impurity associated with D-D and has also been detected in groundwater wells in the state (see HDOH 1985) Fumigants are not likely to be ...
 
...costs, if needed. Heavy arsenic contamination due to the past use of water-based, arsenical herbicides has been identified to depths of greater than ten feet at former ...
 
...concern, these chemicals can still pose leaching threats to underlying groundwater. Comparison to screening levels that do not consider leaching is therefore not appropriate ...
 
... these chemicals in order to prevent and/or cease long-term contamination of drinking water aquifers. 9.1.4.2 Former Field Areas With the local ...
 

9.3 Petroleum Contaminated Sites
...of Total Petroleum Hydrocarbons (TPH). The concentration of TPH in soil and groundwater is typically reported in terms of "carbon ranges," or the number of carbon molecules in individual ...
 
...(HDOH 2011, 2012). Although not studied in detail, dissolved-phase gasoline in groundwater is also likely to be biased towards more soluble, lighter-range compounds. ...
 
... releases of middle distillate fuels. Dissolved-phase, middle-distillate fuel in groundwater could also be biased towards more soluble, "gasoline-range" compounds. A dominance of "TPHg" ...
 
...biased towards more soluble, "gasoline-range" compounds. A dominance of "TPHg" in groundwater samples does not in itself indicate that the source of the contamination is associated with ...
 
...This guidance, Long-Term Management of Petroleum-Contaminated Soils and Groundwater (HDOH, 2007c) is included in TGM Section 19 as Appendix 19-A. The document includes ...
 
...is possible in scenarios where the area and volume of contaminated soil and/or groundwater is minimal. Table 9-5 Target Analytes for Releases of Petroleum Products ...
 
...methane Groundwater Same as soil ...
 
...methane Groundwater Same as soil ...
 
...methane Groundwater same as soil ...
 
... Recommended target analytes for petroleum contaminated soil and groundwater are provided in Table 9-5. Petroleum contamination in soil, water or air/soil ...
 
...are provided in Table 9-5. Petroleum contamination in soil, water or air/soil vapors should be evaluated in terms of both TPH and a short list of target "indicator ...
 
... 9.3.1.2 Total Petroleum Hydrocarbons Soil, groundwater, and soil vapor samples must always be tested for TPH (or equivalent) in addition to targeted, ...
 
...range" (e.g., C10-C24) with respect to traditional, laboratory methods for TPH in soil or water is not applicable to air and vapor samples and can be misleading. The reported concentration ...
 
...basis as warranted. Silica gel cleanup of samples, in particular for surface water and groundwater, should not be carried out without consultation with HDOH. Two options are ...
 
...and groundwater, should not be carried out without consultation with HDOH. Two options are recommended: ...
 
...and evaluate potential hazards posed by TPH-derived, polar breakdown products to drinking water and aquatic habitats in a site-specific EHE (see HDOH 2011). Dissolved-phase ...
 
... in a site-specific EHE (see HDOH 2011). Dissolved-phase TPH in water is composed of unaltered, nonpolar compounds originally in the parent fuel and polar compounds ...
 
...for the sample. The polar compounds, which can dominate the overall mass of TPH in groundwater at aged-release sites, are primarily organic acids/esters and alcohols with variable amounts ...
 
...with these compounds (e.g., toxicity to aquatic organisms, taste and odors in drinking water, etc.) is assumed at an initial screening level to be identical to the parent, nonpolar ...
 
...aquatic ecotoxicity concerns as well as gross contamination concerns (e.g., drinking water taste and odors). Alternative action levels for each environmental hazard should be ...
 
...comparison to data. In most cases, it is anticipated that long-term management of groundwater contaminated primarily with polar, TPH breakdown compounds above HDOH action levels will still ...
 
...even in the absence of apparent risk to human health (e.g., via impacts to drinking water resources). Comparison of data for groundwater samples tested with and without ...
 
...resources). Comparison of data for groundwater samples tested with and without silica gel cleanup could be useful for assessing the state ...
 
...the state of natural biodegradation within a plume of petroleum-contaminated groundwater and optimizing remedial and monitoring actions. For example, no further active remediation ...
 

10.3 Data Quality Assurance Procedures
...(triplicates for MIS). Groundwater duplicates 1 per day for every 10 samples ...
 
... Source blanks 1 per water source per investigation, if used to decontaminate equipment for re-use. ...
 
...a Relative Standard Deviation (RSD) percent: Groundwater field duplicates are evaluated by determining a RPD for the replicates, using RPD formula as ...
 
...introduced into the analytical process Impurities detected in final decontamination rinse water that may not have originated from the site Contaminants originating from exposure ...
 
...via separate temperature blanks. These blanks are containers of analyte-free water included with field samples, handled and transported in the same manner and measure for ...
 
...some cases, additional care must be taken to evaluate comparability. For instance, groundwater samples handled in the exact same fashion, collected within the same sampling event, ...
 

10.5 Field Equipment and Laboratory Instrument Calibration
... 10.5.1 Field Equipment Calibration Investigations of soil, water, or gas phase matrices utilize variety of field equipment, such as a photo-ionization detector ...
 
...(PID) or flame-ionization detector (FID) to measure volatile constituents in soil sample, water quality measurement instruments, or a flow controller to limit or regulate the flow of gas. ...
 

10.6 Field QA/QC
...is strongly dependent upon a variety of factors including the sample matrix (i.e., soil, water, or gas phase), COPCs, and QA/QC questions to be answered. The number of field QA/QC samples ...
 
...or triplicate samples collected from within the same decision unit or from the same groundwater well to evaluate the precision of the sampling effort. Replicates are to be collected, preserved, ...
 
... 10.6.1.1 Discrete Sampling Replicates In general, for discrete sampling of groundwater or soil the HEER Office recommends collecting one replicate QA/QC sample per field day per ...
 
...sample data compared to ensure these DQO are met. Duplicate groundwater samples For non-volatile groundwater contaminants collected in vials, generally two sample ...
 
...samples For non-volatile groundwater contaminants collected in vials, generally two sample containers are "alternately" filled. ...
 
...be filled by going back and forth with the discharge tubing. For volatile groundwater contaminants, where multiple 40 ml vials are commonly used for each sample and loss of volatiles ...
 
...a trip blank. Prepare trip blanks by filling sample containers with reagent grade water, then assuring that the trip blank sample containers accompany the main sample containers ...
 
...step to the analytical laboratory. Trip blanks are not opened in the field. Trip blank water should be from the same source as the method blank water used in the laboratory. ...
 
...should be from the same source as the method blank water used in the laboratory. 10.6.2.2 Field Equipment Rinsate Blanks ...
 
...and transport conditions. An equipment blank is collected by pouring reagent grade water over/through decontaminated equipment used in sample collection. The water is then collected ...
 
...over/through decontaminated equipment used in sample collection. The water is then collected in a sample container and analyzed for the contaminants of interest. Equipment ...
 
...in a sample container and analyzed for the contaminants of interest. Equipment blank water should be from the same source as the method blank water used in the laboratory. ...
 
...should be from the same source as the method blank water used in the laboratory. The use of field equipment rinsate blanks is important for ultraclean ...
 
...not include equipment rinsate blanks, and discuss the rationale for this decision. Field (water) source blanks are required to be analyzed whenever equipment is decontaminated in the field. ...
 
... 10.6.2.3 Field Source Blank Field source blanks are collected from the water source used for decontamination rinse of equipment, and are used to assess potential for contamination ...
 
... rinse of equipment, and are used to assess potential for contamination in the water used for decontamination. One source blank is collected from each source of water ...
 
... used for decontamination. One source blank is collected from each source of water used for decontamination. 10.6.3 Documentation Document ...
 

Contents
... 11.1.2 Water Sample Containers   ...
 
... 11.1.2.1 Non-Volatile Water Sample Containers   ...
 
... 11.1.2.2 Volatile Water Sample Containers   ...
 
... Laboratory Methods, Containers, Preservation, and Holding Times for Groundwater Samples   ...
 

11.0 Handling and Analysis of Samples
...analytical methods for each sampling event. This section focuses on soil and groundwater samples collected as part of an environmental investigation, which are sent to a fixed laboratory ...
 
...presented on the use of soil sampling equipment in Section 5 and on the use of groundwater or surface water sampling equipment in Section 6. A discussion of gas phase samples is not ...
 
...or surface water sampling equipment in Section 6. A discussion of gas phase samples is not included ...
 

Appendices
... Laboratory Methods, Containers, Preservation, and Holding Times for Groundwater Samples ...
 

11.1 Sample Containers
... Table 11-B in the Appendix 11-B present the recommended sample containers for groundwater. The sample volumes for the containers listed in the tables represent the recommended size ...
 
...container may be required for the associated parameter and method. If soil or groundwater samples are to be analyzed for multiple contaminants, the sample volumes listed in the tables ...
 
...for volatile analysis is discussed in Section 4.2.7. 11.1.2 Water Sample Containers The type of sample container used for collecting surface water or groundwater ...
 
...Sample Containers The type of sample container used for collecting surface water or groundwater samples is dependent upon the specific analysis to be performed. Other factors, ...
 
...or groundwater samples is dependent upon the specific analysis to be performed. Other factors, such as ...
 
... the presence of free product are also important to consider when selecting appropriate water sample containers. In general, water sample containers may be grouped into the following ...
 
...sample containers. In general, water sample containers may be grouped into the following two broad categories: (1) non-volatile ...
 
...containers may be grouped into the following two broad categories: (1) non-volatile water sample containers, and (2) volatile water sample containers. 11.1.2.1 ...
 
...sample containers, and (2) volatile water sample containers. 11.1.2.1 Non-Volatile Water Sample Containers ...
 
...sample containers. 11.1.2.1 Non-Volatile Water Sample Containers Water samples for organic non-volatile analysis are typically collected ...
 
...Sample Containers Water samples for organic non-volatile analysis are typically collected in 1 liter amber glass jars ...
 
...1 liter amber glass jars without the use of chemical preservatives. When collecting groundwater samples, fill the water sample containers by directing the outlet of the sampling ...
 
... samples, fill the water sample containers by directing the outlet of the sampling device (i.e., pump tubing or bailer) ...
 
...pump tubing or bailer) toward the top and side of the sample container to allow the water to run down the inside of the bottle. Avoid agitation and the creation of bubbles when collecting ...
 
...the inside of the bottle. Avoid agitation and the creation of bubbles when collecting water samples. To prevent cross contamination, avoid contacting the interior or top of the sample ...
 
...of the sample containers with either the sampling device or gloved hands. Water samples for dissolved metals analysis are collected in 250 milliliter (mL) plastic bottles ...
 
...to collection as discussed in Section 6. 11.1.2.2 Volatile Water Sample Containers Water samples for volatile analysis are typically collected in 40 mL ...
 
...Sample Containers Water samples for volatile analysis are typically collected in 40 mL glass jars with septum-sealed ...
 
...be carefully placed on the jars and sealed with zero headspace. When collecting groundwater samples for volatile analysis, fill the 40 mL jars by directing the outlet of the sampling ...
 
...of the sampling device toward the top and side of the sample container to allow the water to run down the inside of the bottle. Adjust the flow rate of the water sampling device ...
 
...to run down the inside of the bottle. Adjust the flow rate of the water sampling device so that it does not cause the jars to rapidly overflow, causing loss of VOCs, ...
 
...sample preservative. Avoid agitation and the creation of bubbles when collecting volatile water samples to prevent the loss of volatile constituents. To prevent cross contamination, avoid ...
 
...device or gloved hands. The preservative HCl may react (effervesce) with turbid water containing calcareous particulates, resulting in a loss of volatile constituents. If a strong ...
 
...If a strong reaction is observed when filling the 40 mL jars containing HCl, collect the water samples for volatile analysis as unpreserved samples and note on the chain-of-custody. The ...
 
...as unpreserved samples and note on the chain-of-custody. The collection of unpreserved water samples reduces the hold time of 14 days down to 7 days. ...
 

11.2 Sample Preservation and Hold Times
...HOLD TIMES This section presents the recommended sample preservation for soil and water sample collection. Always consult with the laboratory when planning fieldwork to ensure ...
 
...in the Appendices, present the recommended preservation and hold times for soil and groundwater, respectively. Sample preservation consists of methods to assure the samples analyzed ...
 
... process in the field by placing the sample containers in an insulated cooler containing water ice or frozen gel packs. Use of water ice is generally considered by the HEER Office to be ...
 
...ice or frozen gel packs. Use of water ice is generally considered by the HEER Office to be more efficient to rapidly cool samples, ...
 
... chemical reagents from the analytical laboratory. Carefully place the soil or groundwater samples into the sample containers to minimize loss of chemical preservative as well ...
 
...preservative as well as volatile constituents in the sample (i.e., do not overfill water sample containers or leave the cap off a jar containing methanol for soil samples). ...
 
...sample media. For example, calcareous soil may react with sodium bisulfate; turbid groundwater collected from a coral aquifer formation may react with hydrochloric acid. If the sample media ...
 
... Some samples collected for specific analysis, such as dissolved metals in groundwater, may require pre-treatment prior to collection, as well as preservation (see ...
 
... Section 6.0). 11.2.3 Sample Hold Times The soil and water samples should be analyzed as soon as possible after collection. Hold times are the maximum ...
 
...mass of soil) and immediately extruded into a glass jar containing laboratory grade water must be analyzed within 14 days from the time of sample collection only if the samples ...
 

11.3 Sample Control and Chain-of-Custody Procedures
...sample collection (petroleum odor or staining in soil, petroleum product or sheen on water surface) a cross reference of primary and replicate QA/QC samples The ...
 
...media in chain-of-custody batches for submittal to the laboratory (i.e., submit groundwater samples on one chain-of-custody batch separate from soil samples collected for the same project). ...
 

11.4 Sample Shipping
...with padding to minimize movement against each other. Containers for water samples should be packed in an upright position and not stacked on their sides. When shipping ...
 
...should be packed in an upright position and not stacked on their sides. When shipping water samples, line the bottom of the cooler with absorbent material to contain liquids in case of ...
 
...gel ice is convenient to maintain the samples at a temperature of less than 6°C, but water ice may also be used. When using water ice, precautions to prevent spillage from the sample ...
 
...ice may also be used. When using water ice, precautions to prevent spillage from the sample cooler (i.e., containing water ice in ...
 
...ice, precautions to prevent spillage from the sample cooler (i.e., containing water ice in triple bags and sealing the cooler drain) are essential to expedient delivery of the ...
 
... to the laboratory. Line the bottom of the cooler with absorbent material when using water ice in coolers. Immediately prior to shipment, replace the ice or frozen gel packs in ...
 
...should be interpreted as minimum concentrations. When shipping air, soil, or water samples either inter-island or to the mainland, follow all appropriate U.S. Department of Transportation ...
 
... such as FedEx transports the samples. Personnel responsible for shipping soil and water samples in Hawai`i should receive training and refresher training in these regulations. ...
 
...of Agriculture (USDA) inspection and regulation. The USDA does not need to inspect water sample shipments. A "USDA Soil Import Permit" is required to prove that the receiving analytical ...
 
...regulations. Title 40 CFR, Part 261.40(d) states "A sample of solid waste or a sample of water, soil, or air which is collected for the sole purpose of testing to determine its characteristics ...
 
...samples from the field. Note that this provision applies to unpreserved soil and water samples (i.e., no chemical preservatives added during collection). For groundwater ...
 
...(i.e., no chemical preservatives added during collection). For groundwater samples specifically, very small quantities of certain dangerous goods may be transported without ...
 
...bisulfate, hydrochloric acid, nitric acid, sulfuric acid, and sodium hydroxide added to water samples if their pH or percentage by weight criteria is met (USEPA, 1996; USACE, ...
 
...analysis). The above paragraph references the shipment of chemical preservatives in water samples only. ...
 

11.5 Approved Analytical Methods
... 11-B in the Appendices provide the recommended analytical methods for soil and groundwater analysis, respectively. Use other EPA-approved methods (such as Methods for Chemical ...
 
... Use other EPA-approved methods (such as Methods for Chemical Analysis of Water and Wastes (USEPA, 1983) for analyses that measure parameters such as pH, specific ...
 
... include: American Public Health Association (APHA), American Water Works Association, Water Environment Federation. 2005. "Standard Methods for the Examination ...
 
...Works Association, Water Environment Federation. 2005. "Standard Methods for the Examination of Water and ...
 
... Environment Federation. 2005. "Standard Methods for the Examination of Water and Wastewater." 21st Edition (APHA, 2005). ASTM. (updated yearly). "Annual ...
 
... Wastewater." 21st Edition (APHA, 2005). ASTM. (updated yearly). "Annual Book of Standards." West Conshohocken, ...
 

Appendix 11-A Tables
...jar with septum cap Organic-free reagent water and <6°C Laboratory freeze within 48 ...
 
... Organic-free reagent water and <6°C Laboratory ...
 
... Organic-free reagent water and <6°C Laboratory ...
 
... Organic-free reagent water and <6°C Laboratory ...
 
... Organic-free reagent water and <6°C Laboratory ...
 
...indicates that the method comes from Environmental Protection Agency (EPA) wastewater and drinking water standards, both published and maintained by the EPA Safe Drinking ...
 
...and drinking water standards, both published and maintained by the EPA Safe Drinking Water Act (SDWA) ...
 
...standards, both published and maintained by the EPA Safe Drinking Water Act (SDWA) and/or Clean Water Act (CWA). For methods that are presented without the ...
 
...Act (SDWA) and/or Clean Water Act (CWA). For methods that are presented without the "EPA" notation, the methods come ...
 

Appendix 11-B Tables
...Methods, Containers, Preservation, and Holding Times for Groundwater Samples ...
 
...indicates that the method comes from Environmental Protection Agency (EPA) wastewater and drinking water standards, both published and maintained by the EPA Safe Drinking ...
 
...and drinking water standards, both published and maintained by the EPA Safe Drinking Water Act (SDWA) ...
 
...standards, both published and maintained by the EPA Safe Drinking Water Act (SDWA) and/or Clean Water Act (CWA). For methods that are presented without the ...
 
...Act (SDWA) and/or Clean Water Act (CWA). For methods that are presented without the "EPA" notation, the methods come ...
 

Contents
... Summary of Action Levels Used to Select Tier 1 Soil and Groundwater EALs for Benzene   ...
 
...Identification Page, Using Benzene at Noted Concentration in Soil and Groundwater as an Example   ...
 
...Surfer EHE Summary Report, Using Benzene at Noted Concentration in Soil and Groundwater as an Example   ...
 
... Environmental Hazard Map for Hypothetical Site with Groundwater Contamination   ...
 

13.0 Environmental Hazard Evaluation
...Screening for Environmental Hazards at Sites with Contaminated Soil and Groundwater (HDOH, 2011). Environmental Hazard Evaluation (EHE) is the link between site investigation ...
 
...carried out to address hazards posed by the presence of contaminated soil and groundwater, as shown in Figure 13-1. Figure 13-1. Expanded Overview ...
 
...or absence of potential environmental hazards associated with contaminated soil and groundwater is determined and summarized in an EHE (i.e., a review of potential environmental hazards), ...
 
...of a basic understanding of environmental hazards posed by contaminated soil or groundwater run the risk of being incomplete, and require unanticipated, additional field work. This can ...
 
...Screening for Environmental Hazards at Sites with Contaminated Soil and Groundwater (HDOH, 2011). Readers unfamiliar with the concept of environmental hazard evaluation may be ...
 

Figures
... Summary of Action Levels Used to Select Tier 1 Soil and Groundwater EALs for Benzene   ...
 
...Identification Page, Using Benzene at Noted Concentration in Soil and Groundwater as an Example   ...
 
...Surfer EHE Summary Report, Using Benzene at Noted Concentration in Soil and Groundwater as an Example   ...
 
... Environmental Hazard Map for Hypothetical Site with Groundwater Contamination ...
 

13.1 Target Environmental Hazards
... Contaminated Groundwater ...
 
... - Drinking Water Toxicity ...
 
... Toxicity concerns related to contamination of groundwater that is a current or potential source of drinking water ...
 
...that is a current or potential source of drinking water ...
 
... Emission of volatile contaminants from groundwater and intrusion into overlying buildings ...
 
... Discharges of contaminated groundwater and toxicity to aquatic organisms. Includes contamination of fish and shellfish ...
 
... Includes taste and odor concerns for contaminated drinking water supplies, free product, sheens and odors on surface water, general resource ...
 
...supplies, free product, sheens and odors on surface water, general resource degradation, etc. ...
 
... Leaching of contamination from soil by infiltrating surface water (rainfall, irrigation, etc.) and subsequent contamination of groundwater ...
 
...(rainfall, irrigation, etc.) and subsequent contamination of groundwater resources ...
 
... Emission of volatile contaminants from soil or groundwater into overlying buildings and/or outdoor air. ...
 
... The four target media tested to evaluate these potential hazards are groundwater, soil, soil gas and indoor air. A summary ...
 
...utility activities that require disturbance of heavily contaminated soil or groundwater. Leaching of contaminants from soil is also important to consider, even though this ...
 
...this is rarely included in traditional risk assessments. Discharges of contaminated groundwater or free product into nearby surface water bodies, either naturally or via leakage ...
 
... or free product into nearby surface water bodies, either naturally or via leakage into storm sewers or through site dewatering activities, ...
 
...bodies, either naturally or via leakage into storm sewers or through site dewatering activities, can pose significant environmental hazards to aquatic habitats. When large plumes ...
 
...environmental hazards to aquatic habitats. When large plumes of impacted groundwater threaten fisheries, the discharge of contaminated groundwater to surface water and subsequent ...
 
...threaten fisheries, the discharge of contaminated groundwater to surface water and subsequent uptake of contaminants into seafood may also be of concern. ...
 
...to surface water and subsequent uptake of contaminants into seafood may also be of concern. This includes the ...
 
...hazards to terrestrial flora and fauna (e.g., barium, copper, nickel). Drinking water toxicity hazards are almost always identified for contaminated aquifers. Potential vapor intrusion ...
 
...aquifers. Potential vapor intrusion hazards will also usually be identified for groundwater contaminated with carcinogenic, volatile chemicals. Chemicals that have a low taste ...
 
...not pose toxicity concerns but can still pose gross contamination hazards for drinking water resources (e.g., TPH, ethylbenzene, toluene, xylenes). A number of pesticides pose aquatic ...
 
...number of pesticides pose aquatic toxicity hazards at concentrations well below drinking water standards. This can drive remedial actions if discharge of contaminated groundwater into a ...
 
...standards. This can drive remedial actions if discharge of contaminated groundwater into a sensitive aquatic habitat is possible. Free product could pose both toxicity and gross ...
 
...gross contamination hazards if allowed to migrate offsite and discharge into a surface water body. Free product also poses potential vapor intrusion hazards for nearby buildings as well ...
 
...attention at some sites, including exposure of construction workers to contaminated groundwater and the potential uptake of contaminants in garden produce. The need to include additional ...
 

13.2 Tier 1 Environmental Action Levels
...guidance (HDOH, 2011). This guidance presents soil gas as well as soil and groundwater action levels for screening of potential vapor intrusion hazards. The action levels are periodically ...
 
...This is used in part to caution against use of the HDOH soil gas, soil and groundwater action levels for vapor intrusion in colder areas of the US where heating and overall building ...
 
...Indoor Air:Subslab Soil Gas attenuation factors used to develop the HDOH soil, groundwater, soil gas ("vapor") and indoor air action levels for potential vapor intrusion hazards are ...
 
...and soil gas action levels are based in part on similar guidance prepared by a Regional Water Board office of the California EPA (CalEPA, 2005c; prepared by the same author as the ...
 
...gas action levels (see HDOH, 2011). Note that the USEPA vapor intrusion model for groundwater calculates a vapor flux rate of 67.4 cm3/second or 4.0 L/minute, based on input, default building ...
 
...(see HDOH, 2011, Appendix 4). This generates an AF of 0.0010 (1/1,017) as used the groundwater vapor intrusion models. The AFs used between the soil gas and groundwater models are therefore ...
 
...vapor intrusion models. The AFs used between the soil gas and groundwater models are therefore consistent. The residential AF was divided by two (0.0005) for development ...
 
...see Section 7.7.1). Virtually any detection of volatile chemicals in soil, groundwater, soil vapors, or indoor air would trigger a time and cost consuming assessment of ...
 

13.3 Steps to Environmental Hazard Evaluation
...Levels (Tier 1 EALs) are concentrations of contaminants in soil, soil gas and groundwater below which the contaminants are assumed to not pose a significant threat to human health or ...
 
...Screening for Environmental Hazards at Sites with Contaminated Soil and Groundwater (HDOH, 2011). The EALs described in the EHE document are not intended to establish policy or ...
 
...of site environmental conditions with respect to contaminated soil and groundwater and related environmental hazards (see Section 3.4.3). Four default CSMs were used ...
 
...Four default CSMs were used to develop The Tier 1 EALs (HDOH, 2011): Groundwater affected or potentially affected by the release is a current or potential drinking water ...
 
...affected or potentially affected by the release is a current or potential drinking water resource; site located within 150m of a surface water body. Groundwater affected ...
 
...resource; site located within 150m of a surface water body. Groundwater affected or potentially affected by the release is a current ...
 
...body. Groundwater affected or potentially affected by the release is a current or potential drinking water ...
 
...affected or potentially affected by the release is a current or potential drinking water resource; site not located within 150m of a surface water body. Groundwater affected ...
 
...resource; site not located within 150m of a surface water body. Groundwater affected or potentially affected by the release is not a current ...
 
...body. Groundwater affected or potentially affected by the release is not a current or potential drinking ...
 
...or potentially affected by the release is not a current or potential drinking water resource; site located within 150m of a surface water body. Groundwater affected ...
 
...resource; site located within 150m of a surface water body. Groundwater affected or potentially affected by the release is not a current ...
 
...body. Groundwater affected or potentially affected by the release is not a current or potential drinking ...
 
...or potentially affected by the release is not a current or potential drinking water resource; site not located within 150m of a surface water body. Only ...
 
...resource; site not located within 150m of a surface water body. Only surface water bodies that are hydraulically connected to groundwater ...
 
...body. Only surface water bodies that are hydraulically connected to groundwater are considered to be potentially threatened ...
 
...bodies that are hydraulically connected to groundwater are considered to be potentially threatened by contaminated groundwater. For the purposes of ...
 
...are considered to be potentially threatened by contaminated groundwater. For the purposes of the Tier 1 EALs, it is further assumed under each default CSM that contaminated ...
 
...Evaluation of Environmental Hazards at Sites with Contaminated Soil and Groundwater for additional information on site conditions assumed for development of the Tier 1 EALs (HDOH, ...
 
...selection of Tier 1 EALs for benzene is presented in Figure 13-4 (surface soils, drinking water resource threatened, unrestricted land use desired). For soil, the action level ...
 
...as the Tier 1 EAL [refer to lookup tables in HDOH EAL document (HDOH, 2011)]. For groundwater, the action level for drinking water toxicity concerns drives environmental hazards and is ...
 
...the action level for drinking water toxicity concerns drives environmental hazards and is selected as the Tier 1 EAL (5 ug/L, the ...
 
...environmental hazards and is selected as the Tier 1 EAL (5 ug/L, the primary drinking water standard). Figure 13-3 Summary ...
 
... Figure 13-4. Summary of Action Levels Used to Select Tier 1 Soil and Groundwater EALs for Benzene. CSM A based on (1) groundwater is a drinking water resource, and ...
 
... EALs for Benzene. CSM A based on (1) groundwater is a drinking water resource, and (2) site within 150m of a surface water body. For ...
 
...is a drinking water resource, and (2) site within 150m of a surface water body. For soil and groundwater, ...
 
...resource, and (2) site within 150m of a surface water body. For soil and groundwater, the lowest action level for environmental hazards is ...
 
...body. For soil and groundwater, the lowest action level for environmental hazards is selected as the final Tier 1 ...
 
...simply select the appropriate site scenario information from the pull-down list (groundwater utility, distance to nearest surface water body, land use, etc.), select the target contaminant, ...
 
...utility, distance to nearest surface water body, land use, etc.), select the target contaminant, and (optional) input the representative ...
 
...(optional) input the representative concentration of the contaminant in soil and/or groundwater. If included, the input concentration is compared to action levels for specific environmental ...
 
...for leaching hazards are unchanged because land use does not alter the threat to groundwater. Groundwater action levels for vapor intrusion hazards are also higher for a commercial/industrial ...
 
...Groundwater action levels for vapor intrusion hazards are also higher for a commercial/industrial land ...
 
...soil is located within three meters of the ground surface ("shallow") and overlies groundwater that is a current or potential source of drinking water. The site is within 150 meters ...
 
...that is a current or potential source of drinking water. The site is within 150 meters of a surface water body. In the example ...
 
...The site is within 150 meters of a surface water body. In the example (i.e., Figures 13-5a, 13-5b, and 13-5c), the input concentration ...
 
...not flagged as potential hazards. The input concentration of 150 ug/L benzene in groundwater flags drinking water toxicity concerns and aquatic ecotoxicity concerns, but no other potential ...
 
...flags drinking water toxicity concerns and aquatic ecotoxicity concerns, but no other potential hazards. ...
 
...used for this example was 5.1 mg/kg benzene in soil, and 150ug/L benzene in groundwater. Also, check for updates. The EAL Surfer is updated periodically and the page configurations ...
 
...Identification Page, Using Benzene at Noted Concentration in Soil and Groundwater as an Example. Refer also to Figure13-5a. ...
 
...Surfer EHE Summary Report, Using Benzene at Noted Concentration in Soil and Groundwater as an Example. Refer also to Figure13-5a. This page can be printed and included in ...
 
...determine the extent of investigation needed at a site where contaminated soil or groundwater is identified. The list of Chemicals of Potential Concern (COPCs) can be quickly narrowed down ...
 
...Concern (COPCs) can be quickly narrowed down by direct comparison of soil and groundwater data to the Tier 1 EALs (HDOH, 2011). Further consideration of contaminants that do not exceed ...
 
...and Section 9 ). If the reported concentration of volatile contaminants in soil or groundwater exceed action levels for vapor intrusion concerns, then soil gas data can be collected ...
 
...of potential environmental hazards associated with contaminated soil and groundwater (refer to Section 3.4). With the exception of gross contamination, most of the environmental ...
 
...action levels in this guidance helps expedite this evaluation. A detailed review of groundwater data can sometimes be used in place of soil action levels to better evaluate leaching and groundwater ...
 
...sometimes be used in place of soil action levels to better evaluate leaching and groundwater contamination concerns. In other cases, additional laboratory tests and/or use of environmental ...
 
...levels to understand the specific environmental hazards posed by contaminated groundwater is especially important. Identifying toxicity hazards and taste and odor hazards in groundwater ...
 
...is especially important. Identifying toxicity hazards and taste and odor hazards in groundwater that is currently used as a source of drinking water is obviously important. Expeditious actions ...
 
...that is currently used as a source of drinking water is obviously important. Expeditious actions to address vapor intrusion hazards posed by contaminated ...
 
...soil are usually warranted. In contrast, long-term monitoring may be acceptable for groundwater that poses only gross contamination hazards (e.g., toxicity-based action levels for currently ...
 
...contamination hazards (e.g., toxicity-based action levels for currently unused drinking water resources not exceeded) or potential aquatic toxicity hazards if it were to migrate offsite ...
 
...toxicity hazards if it were to migrate offsite and discharge into a body of surface water. Long-term management will be required for sites where soil and groundwater contaminated ...
 
... Long-term management will be required for sites where soil and groundwater contaminated above levels of potential concern cannot be remediated in a relatively short time ...
 
...acceptable alternatives) should be used to delineate areas of contaminated soil and groundwater that will require long-term management as well as the specific environmental hazards posed ...
 
...commercial laboratory Method Reporting Limits (MRLs) for a number of chemicals in groundwater. This is not generally the case for soil. As discussed in the EHE guidance, the laboratory ...
 
... Chemicals with laboratory MRLs that could exceed the HDOH EALs for groundwater are given in Table 13-2. If the reported concentration of a chemical exceeds ...
 
... Groundwater Soil ...
 

13.4 Preparation of Environmental Hazard Evaluation Reports
...' 13.4 CHEMICALS NOT LISTED IN LOOKUP TABLES Soil, groundwater, soil gas and/or indoor air action levels should be developed and approved by HDOH for chemicals ...
 

13.5 Human Health Risk Assessments
...to identify potential environmental hazards at a site as soon as initial soil, groundwater and other data are received. As discussed above, this is used to guide completion of the site ...
 
...HDOH Screening for Environmental Hazards at Sites with Contaminated Soil and Groundwater guidance document (HDOH, 2011). The list of COPCs can be quickly narrowed down ...
 
...and the representative concentration of target COPCs within each DU determined. For groundwater and soil gas samples, direct reference to reported concentrations of COPCs in single ...
 
...Screening for Environmental Hazards at Sites with Contaminated Soil and Groundwater ["EHE guidance" (HDOH, 2011)]. A summary of commonly used approaches is provided in Tables ...
 
...a much lower vapor intrusion hazard than predicted by simple comparison of soil or groundwater data to HEER Office action levels. The additional data could negate the need for remedial actions ...
 
...identify the presence of contamination that was not detected in earlier soil and groundwater sample collection. Preparing a traditional human health risk assessment or ecological ...
 
...on toxicological risks associated with direct exposure to contaminated soil, groundwater, or air. While this is important, direct exposure is only one of several potential environmental ...
 
...Table 13-3 Commonly Used Approaches for Evaluating Environmental Hazards in Groundwater ...
 
... Contamination of drinking water resources ...
 
... �    Identification and monitoring of nearby, groundwater supply wells and guard wells ...
 
... �    Long-term monitoring of groundwater to evaluate plume migration potential ...
 
... potential �    Use of groundwater plume fate & transport models in combination with long-term monitoring ...
 
... �    Use of groundwater data to evaluate plume expansion and migration over time ...
 
...transport models to predict long-term migration potential of groundwater contaminant plumes �    Preparation ...
 
... �    Check groundwater for free product �    Check discharge ...
 
... �    Collection of groundwater data �    Use of HDOH laboratory ...
 
...area, not the site as a whole, is the target where the "receptor" of concern is the groundwater directly underneath the contaminated soil. If Tier 1 soil action levels for leaching ...
 
...out. Keep in mind that soil data are not necessarily good indicators of potential groundwater contamination. This is especially true for chlorinated solvents. Releases of wastewater contaminated ...
 
...contamination. This is especially true for chlorinated solvents. Releases of wastewater contaminated with solvents may not leave an identifiable smear zone in vadose-zone soil due ...
 
...solvent compounds, even though the release results in significant contamination of groundwater. Soil or groundwater data flagged for potential vapor intrusion almost always indicates ...
 
... Soil or groundwater data flagged for potential vapor intrusion almost always indicates that soil gas samples should ...
 
...gas samples should be collected at the site. The model used to develop the soil and groundwater actions levels for vapor intrusion hazards estimates the concentration of a volatile contaminant ...
 
...located in this area. Documenting where grossly contaminated soil and groundwater will be left in place at a site is also important (e.g., Figure 13-7). Gross contamination ...
 
...13-7). Gross contamination hazards often drive the cleanup of contaminated soil and groundwater, not direct exposure or even leaching hazards. Over time, grossly contaminated soil and groundwater ...
 
...direct exposure or even leaching hazards. Over time, grossly contaminated soil and groundwater can generate methane and related explosive hazards. Although the contamination may not pose ...
 
...current site conditions, the unexpected discovery of grossly contaminated soil and groundwater during subsurface construction or utility activities can result in significant delays and project ...
 
... Figure 13-7. Environmental Hazard Map for Hypothetical Site with Groundwater Contamination. Hypothetical site contaminated with petroleum. Areas delineated by ...
 
...intrusion hazard so property can be redeveloped. Aggressive remediation of groundwater that poses acute aquatic toxicity hazards and gross contamination (odors, sheens) within ...
 
...of the shoreline is also recommended. Long-term monitoring of remaining groundwater contamination required (see text). ...
 
... over time, etc. When practicable, full cleanup of contaminated soil and groundwater to permit future, unrestricted use of the property is desirable. A detailed discussion ...
 
... of contaminated soil to prevent exposure or leaching, long-term monitoring of groundwater, etc. These actions must be described in a site-specific EHMP. The preparation of ...
 

13.6 Ecological Risk assessements
...document Screening for Environmental Hazards at Site with Contaminated Soil and Groundwater (HDOH, 2011). A summary of the type of information that should be included in the report is ...
 
... Identify all types of impacted media (soil, groundwater, surface water, etc.). Identify all sources of chemical releases. ...
 
...surface water, etc.). Identify all sources of chemical releases. ...
 
...(include maps of site with isoconcentration contours for soil and groundwater as practicable). Identify nearby groundwater extraction wells, ...
 
...as practicable). Identify nearby groundwater extraction wells, bodies of surface water and other potentially sensitive ecological ...
 
...extraction wells, bodies of surface water and other potentially sensitive ecological habitats. Ensure data are representative ...
 
... addition to an Environmental Hazard Evaluation)? Do soil and groundwater conditions at the site differ significantly from those assumed in development of ...
 
...health effects been identified? Selection of soil and groundwater categories: State the regulatory beneficial use ...
 
...State the regulatory beneficial use of impacted or potentially impacted groundwater beneath the site; discuss the actual, likely beneficial use of groundwater based ...
 
...beneath the site; discuss the actual, likely beneficial use of groundwater based on measured or assumed quality of the groundwater and the hydrogeologic nature ...
 
...based on measured or assumed quality of the groundwater and the hydrogeologic nature of the soil or bedrock containing the groundwater. Characterize ...
 
...and the hydrogeologic nature of the soil or bedrock containing the groundwater. Characterize the soil type(s) and location of impacted soil as ...
 
...data to the selected summary Tier 1 EALs and identify areas of soil or groundwater that pose potential environmental hazards. Identification ...
 
...to potentially harmful levels of contaminants in soil ("direct exposure"), impacts to water supply wells, intrusion of vapors or methane into overlying structures (including explosive ...
 
...structures (including explosive hazards) and discharges of free product to surface water. Note that the approach described above was referred to as Environmental Risk Assessment ...
 
...assess the need for potential cleanup actions at sites where contaminated soil and groundwater are identified. ...
 

14.2 Removal Actions for Non-Emergency Environmental Cleanups
...for a contaminated pond may include: Achieving protective soil and surface water quality (e.g. representative samples with levels below Tier 1 EALs [HDOH, 2008] for soil ...
 
...samples with levels below Tier 1 EALs [HDOH, 2008] for soil and surface waters) Reducing possible future impacts to groundwater Restoring the pond to stable conditions ...
 
... Reducing possible future impacts to groundwater Restoring the pond to stable conditions where vegetation and animals may be re-established ...
 
...threats posed by residual contamination of subsurface soils and non-drinking groundwater also exist, these less imminent hazards may be left for a non-emergency removal or remedial ...
 

15.1 FTC Overview
...the "Evaluation of Environmental Hazards at Sites with Contaminated Soil and Groundwater" (HDOH, 2008). 15.1.1 Difference from Other Approaches While ...
 

15.3 Screening And Eligibility
... Contamination that is known or likely to extend across a property boundary Groundwater contamination, especially in a drinking water aquifer Soil contamination that has a migration ...
 
...contamination, especially in a drinking water aquifer Soil contamination that has a migration pathway to a drinking water aquifer ...
 
...aquifer Soil contamination that has a migration pathway to a drinking water aquifer Site is adjacent to sensitive communities or residences Site is adjacent to ...
 

15.5 Site Assessment Process
...site conditions in order to identify the necessity for remediating soil or groundwater that poses unacceptable environmental hazards, either under current site conditions or under ...
 
...site assessment is carried out by the collection and analyses of samples of soil, groundwater, soil gas, surface water, sediment, air and/or other media as needed. The EALs may be used ...
 
...soil gas, surface water, sediment, air and/or other media as needed. The EALs may be used to identify contamination ...
 
...or absence of potential hazards may be identified and the contaminated soil or groundwater quickly remediated without further assessment. In cases where cleanup costs could ...
 

15.6 Site Cleanup Process
... Cause of release or threat Site history General site geology, hydrology, groundwater status, adjacent land uses Distance to surface water bodies Site investigation and ...
 
...status, adjacent land uses Distance to surface water bodies Site investigation and environmental hazard evaluation Removal alternatives ...
 

Contents
... 16.2.2.4 Groundwater Remedial Actions   ...
 

16.0 Remedial Actions
...decide on a remedial action approach under the following conditions: Groundwater contamination, especially in a drinking water aquifer Soil contamination with a direct migration ...
 
...contamination, especially in a drinking water aquifer Soil contamination with a direct migration pathway to a nearby drinking water aquifer ...
 
...aquifer Soil contamination with a direct migration pathway to a nearby drinking water aquifer Contamination (soil or groundwater) crosses property boundaries Contaminants ...
 
...aquifer Contamination (soil or groundwater) crosses property boundaries Contaminants are present at high levels or consist of complex ...
 

16.1 Conducting a Remedial Investigation
...municipal landfills, volatile organic compounds (VOCs) in soils, and contaminated groundwater for Comprehensive Environmental Response, Compensation & Liability Act (CERCLA) ...
 

16.2 Setting Remedial Action Objectives and Conducting a Remedial Alternatives Analysis
... the United States (U.S.) Clean Air Act and HRS 342B. Effluent discharge limits on wastewater discharges from an on-site treatment process - regulated by the U.S. Clean Water Act and ...
 
...discharges from an on-site treatment process - regulated by the U.S. Clean Water Act and HRS 342D. Grading, stockpiling, trenching - regulated by various county ordinances. ...
 
...to the EALs provided in Evaluation of Hazards at Sites with Contaminated Soil and Groundwater (HDOH, 2008). Known or suspected carcinogens: Cleanup levels should be concentrations ...
 
... to the EALs provided in Evaluation of Hazards at Sites with Contaminated Soil and Groundwater (HDOH, 2008). Ecological receptors: Where these concerns are identified, cleanup levels ...
 
...their molecular structures, and, in principle, may be converted into carbon dioxide, water, and inorganic salts. Hazardous substances that pose a threat due to corrosivity or reactivity ...
 
...vapor extraction to extract volatile contaminants from subsurface soils Groundwater extraction, filtration by activated carbon, and disposal of the carbon in an approved ...
 
...barriers or active ventilation systems On-site containment of contaminated groundwater with sheet piles or slurry walls Reducing mobility of free phase petroleum in soil ...
 
...piles or slurry walls Reducing mobility of free phase petroleum in soil or groundwater by removing petroleum to residual saturation or less ...
 
...in place is disturbed in the future. Long-term monitoring of a "stable" groundwater contaminant plume Public notices and advisories against consumption of contaminated ...
 
... into the ground Removal of floating petroleum "free product" from the water table to prevent continued contamination of soil and groundwater Cleanup of contaminated ...
 
...table to prevent continued contamination of soil and groundwater Cleanup of contaminated soil to prevent direct exposure to the public Cleanup of contaminated ...
 
...exposure to the public Cleanup of contaminated soil to prevent leaching impacts to groundwater When remedial alternatives for source control actions are developed, the remedial ...
 
...and, as necessary, institutional controls. 16.2.2.4 Groundwater Remedial Actions Analysis of remedial alternatives for groundwater contamination must ...
 
...Remedial Actions Analysis of remedial alternatives for groundwater contamination must assess varying restoration time periods utilizing different cleanup technologies. ...
 

16.4 Implementing the Cleanup Remedy Selected
...remedial design prior to remedial action implementation. In some cases, such as at groundwater cleanup sites, once the remedial system has been constructed and installed, it may operate ...
 
...at sites where long-term cleanup or monitoring activities are planned, such as groundwater treatment and monitoring, or periodic inspections of engineered controls such as soil caps. ...
 

18.4 Common Report Elements
... Site Description Climate Soils/Geology/Hydrology Surface Water Groundwater (including location of drinking water and other known wells on or near ...
 
... Groundwater (including location of drinking water and other known wells on or near to the site) ...
 
...(including location of drinking water and other known wells on or near to the site) Historic Land Use ...
 

18.5 Document Outlines
... Actual or probable release to groundwater that is a drinking water supply   ...
 
...that is a drinking water supply   ...
 
... Actual or probable release to surface water that is a drinking water supply   ...
 
...that is a drinking water supply   ...
 
...results in releases of hazardous substances Actual/potential human exposures, drinking water contamination Name of HEER Office evaluator and date of evaluation An ...
 
... Actual or potential contamination of drinking water supplies or sensitive ecosystems   ...
 
... 2.1.3 Surface Water   ...
 
... 2.1.4 Groundwater   ...
 
... 5.2 Groundwater Sampling Activities   ...
 
... 2.1.3 Surface Water   ...
 
... 2.1.4 Groundwater   ...
 
... 5.2 Groundwater Sampling Activities   ...
 
... 6.2 Analytical Results of Groundwater Samples   ...
 
... 2.1.3 Surface Water   ...
 
... 2.1.4 Groundwater   ...
 
... 5.3 Groundwater Investigation   ...
 
... 6.3 Groundwater Sampling Procedures   ...
 
... 2.1.3 Surface Water   ...
 
... 2.1.4 Groundwater   ...
 
... 5.4 Groundwater Sampling Activities   ...
 
... 7.3 Groundwater Sampling Observations   ...
 
... 8.1.3 Groundwater Samples   ...
 
... 9.3  Groundwater Sampling Analytical Results   ...
 
... 10.3 & Groundwater   ...
 
...Evaluation of Environmental Hazards at Sites with Contaminated Soil and Groundwater (HDOH, 2008) for a detailed discussion of Environmental Hazard Evaluation. A suggested outline ...
 
... 2.1.3 Surface Water   ...
 
... 2.1.4 Groundwater   ...
 
... 9.3 Targeted Tier 1 Groundwater EALs   ...
 
... 9.4 Comparison of Selected Groundwater EALs to Site Data   ...
 
... 2.1.3 Surface Water   ...
 
... 2.1.4 Groundwater   ...
 
... 2.1.3 Surface Water   ...
 
... 2.1.4 Groundwater   ...
 
... 5.5 Groundwater Sampling Activities   ...
 
... 2.1.3 Surface Water   ...
 
... 2.1.4 Groundwater   ...
 
... 6.2 Groundwater Sampling Activities   ...
 
... 9.0 Soil and Groundwater Management for Future Site Activities Affecting On-Site Contamination ...
 
... 9.2 Pre-Excavation Evaluation of Soils and Groundwater   ...
 
... 9.6 Groundwater Handling   ...
 
... 9.7 Groundwater Disposal 10.0 ...
 

18.6 Supporting Forms and Other Documents
...location identification Sample identification number (if applicable) Depth to water and/or bedrock (refusal) when encountered Soil description Sample recovery (and portion ...
 
...to bottom and top of annular grout Depth to bottom of surface seal Depth to the water table Surface seal and well apron design Protective box/casing and cap designs ...
 
...6, Figure 6-7. 18.6.3 Monitoring Well Abandonment Form A groundwater monitoring well that is no longer needed, sustains damage, or is determined to be improperly ...
 
...Information Well Construction Information, including installation date, depth to groundwater, casing and screening material, etc. General Abandonment Information, including ...
 
... Slot Size: Depth to Water: Screen Length: Screen Depth: ...
 
... Was well set in an aquifer that is current or potential drinking water source? Y / N: Annular Material: ...
 

Contents
... Long-Term Management of Petroleum-Contaminated Soil and Groundwater   ...
 

19.1 Site Closure Scoping
...implications include: Will the remedy restrict future land (or groundwater) use at the site? Will stakeholders concur with the land use restrictions? Will current ...
 
...purchasers in future real estate transactions if contaminated soil and/or groundwater remains on site? What will be the long-term costs of institutional and engineering controls ...
 
... in preventing future site occupants from digging into contaminated soil or groundwater? What potential legal liabilities may be caused by managing contaminated soil or ...
 
...What potential legal liabilities may be caused by managing contaminated soil or groundwater on site? Are landowners and other stakeholders willing to accept those liabilities? ...
 

19.3 Closures with Use Restrictions
...applied in situations where representative contaminant levels are above the soil or groundwater "residential use" EALs, but below applicable "commercial/industrial use" EALs at a site zoned ...
 

19.4 No Further Active Remediation Letter
...of further work when (or if) the site is redeveloped. The need for on-going groundwater monitoring or soil gas monitoring may indicate a No Further Active Remediation Letter is not ...
 
... in HDOH guidance on Long-Term Management of Petroleum-Contaminated Soils and Groundwater (HDOH, 2007c; included as Appendix 19-A). This document outlines procedures for ...
 

19.6 Environmental Hazard Management Plan
...of contaminated soil to prevent exposure or leaching, or long-term monitoring of groundwater, etc. The EHMP must include the following at a minimum (also see Section ...
 
...Clear depiction of the extent and magnitude of remaining contamination in soil, groundwater and/or soil gas, presented on easily readable, to-scale maps with a north arrow ...
 
...hazards Requirements for long-term monitoring of contaminants in soil, groundwater, and/or soil gas Discussion of engineering and/or institutional controls needed ...
 
... Guidance on proper handling, reuse and disposal of contaminated soil and/or groundwater that is encountered during future site activities Specific description of construction ...
 

19.7 Institutional and engineering Controls
...include: Prohibition on excavation of soil Prohibition on use of groundwater Prohibition on residential or other sensitive land use HDOH's primary ...
 
... Capping systems � contaminated soil is covered with a cap to reduce surface-water infiltration and leaching, control gas and odor emissions, improve aesthetics, provide ...
 
...on-site cell or vault. Such systems are designed to eliminate or reduce surface-water infiltration and leaching, control gas and odor emissions, improve aesthetics, and prevent ...
 
... unlined borrow pits may be adequate for on-site management. Groundwater Contamination Hydraulic Containment � measures are used to control the hydraulic gradient ...
 
...measures are used to control the hydraulic gradient to minimize the spread of a groundwater plume. One example is the use of pumping wells to actively prevent the plume from spreading ...
 
...of pumping wells to actively prevent the plume from spreading and reaching drinking water wells, surface water, or uncontaminated aquifers, etc. Another example is a slurry wall ...
 
...wells, surface water, or uncontaminated aquifers, etc. Another example is a slurry wall in which low permeability ...
 
... materials, such as grout, are injected into the subsurface to contain a groundwater plume. Institutional controls are necessary to restrict groundwater use. Alternative ...
 
... plume. Institutional controls are necessary to restrict groundwater use. Alternative Water Source � an alternative water source can be provided to an area ...
 
...use. Alternative Water Source � an alternative water source can be provided to an area where groundwater is contaminated ...
 
...Source � an alternative water source can be provided to an area where groundwater is contaminated and not suitable for ...
 
...source can be provided to an area where groundwater is contaminated and not suitable for ingestion. Institutional controls are necessary to ...
 
...not suitable for ingestion. Institutional controls are necessary to restrict groundwater use. Sediment Contamination Capping systems - contaminated sediments ...
 
...sediments are covered with a cap to eliminate erosion and dissolution into the water body, improve aesthetics, provide a stable surface over the contaminated sediment, and ...
 

Log of TGM Updates
... 6 Groundwater and Surface Water Sampling Guidance Dec 31, ...
 
...and Surface Water Sampling Guidance Dec 31, 2008 ...
 
... Screening for Environmental Hazards at Sites with Contaminated Soil and Groundwater Feb 2005 ...
 

PDF Download Page
... Section 6 - Groundwater and Surface Water Sampling Guidance ...
 
... and Surface Water Sampling Guidance 7.6mb ...
 
...19-A - Long-Term Management of Petroleumcontaminated Soil and Groundwater 231kb ...
 
... Long-term Management of Petroleum-Contaminated Soil and Groundwater. 161kb ...
 

Additional Guidance Documents" Language="VB" MasterPageFile="~/lib/Content.master
... and estimate contaminant concentration in source area leachate and in groundwater. Refer to April 12, 2007 guidance on "Use of Laboratory ...
 
... Soil: Guidance for assessing the potential impact to groundwater posed by leaching of contaminants from vadose-zone soils. This model uses site-specific ...
 
...contaminant concentrations in soil leachate and future impacts to groundwater based on leachate dilution assumptions. See October 2008 ...
 
... Screening for Environmental Hazards at Sites with Contaminated Soil and Groundwater (or "EHE Guidance"). The HEER Office EHE Guidance and HEER Office TGM are the two ...
 
... Environmental Action Levels for Soil, Soil Gas, and Groundwater Environmental Action Levels Surfer (electronic lookup tables) ...
 
...direct exposure, vapor intrusion, leaching and contamination of groundwater, impacts to drinking water resources, impacts to aquatic and terrestrial ...
 
...impacts to drinking water resources, impacts to aquatic and terrestrial ecological habitats, gross ...
 

7.10 Documentation of Soil Vapor or Indoor Air Sampling
...the magnitude and nature of subsurface contamination (e.g., free product on shallow groundwater), concentrations of targeted VOCs in source area and subslab soil vapor samples, presence or ...
 
...during dry periods of the year due to the exposure of subsurface smear zones as the water table falls. If collecting a combination of indoor air samples, outdoor ...
 
...entry points for subsurface vapors include bathrooms, kitchens and utility rooms where water, sewer, gas, electric and telecommunication lines penetrate the floor. Wall outlets for electrical ...
 

7.10 Documentation of Soil Vapor or Indoor Air Sampling
... passive sample collectors should be deployed as near to the suspected soil or groundwater source as possible in order to reduce the chance of placing the sampler in a pocket ...
 

7.10 Documentation of Soil Vapor or Indoor Air Sampling
...petroleum fuels, including diesel and other middle distillate fuels. Unlike soil or groundwater, reporting of TPH compounds as �gasoline-range� or �diesel-range� is not applicable to soil ...
 
...by heavier-end, C10�C26 compounds. This is appropriate for testing of soil and water samples, based on the known or assumed type of fuel released. A distinction ...
 
...(see also Volume 1 of the EHE guidance). Do soil or groundwater analytical results, or other field data, indicate that concentrations of chemicals ...
 

7.10 Documentation of Soil Vapor or Indoor Air Sampling
...concentrations significantly higher than would otherwise be predicted by soil or groundwater data, see HDOH 2011): Unidentified source in nearby, vadose-zone ...
 
... phase (e.g., PCE vapors in dry soil beneath slab of a dry cleaner); Groundwater source area closer than ten feet from soil vapor sample point (default depth to water table ...
 
...source area closer than ten feet from soil vapor sample point (default depth to water table used in models); Non-representative soil data (reliability of most soil ...
 
...discrete samples is very low; see Section 4); Non-representative groundwater data (e.g., heterogeneous plume with isolated �hot spots� nearby); or Relict vapor ...
 
...vapor plume associated with earlier migration of more heavily contaminated groundwater through area in past or post remediation of groundwater contamination. ...
 
...through area in past or post remediation of groundwater contamination. The heterogeneity of contaminants in groundwater plumes has not ...
 
...contamination. The heterogeneity of contaminants in groundwater plumes has not been studied in detail. Heterogeneity can be expected to be significantly greater ...
 
...others: Source area size and volume (e.g., free product on groundwater >100m2 in area and/or >10m3 contaminated soil present; refer to HDOH 2007c); ...
 
...HDOH 2007c); Mass of VOCs present in the source media (e.g., soil or groundwater) and associated volume of contaminated soil necessary to sustain long-term, vapor emissions ...
 
...associated with a relatively small source area of petroleum-contaminated soil or groundwater. In contrast, measures to eliminate potential vapor pathways might be required at a site where ...
 
...of the absence of clear impacts to existing buildings if source area soil, groundwater and/or soil vapor data suggest potential future vapor intrusion risks or other environmental ...
 
...technical memorandum Long-Term Management of Petroleum-Contaminated Soil and Groundwater (HDOH 2007c). As a general rule a home or building should not be flagged for potential ...
 
...within the limitations described in the EHE document (HDOH 2011), VOCs in groundwater or soil vapor below the corresponding Tier 1 EALs can be assumed to not pose a significant ...
 

7.10 Documentation of Soil Vapor or Indoor Air Sampling
...soil vapor or indoor air sampling locations. The relative location of soil and groundwater contamination with respect to locations of sampling probes and all current or proposed future ...
 

13.6 Ecological Risk assessements
...each environmental medium (e.g., COPCs for soil may be different that the COPCs for groundwater). The identified list of COPCs will be the focus of the HHRA. 13.7.1.2 EXPOSURE ...
 

Appendices
... Long-Term Management of Petroleum-Contaminated Soil and Groundwater.   ...
 

Appendix 19-A Long-Term Management of Petroleum-Contaminated Soil and Groundwater
... APPENDIX 19-A Long-Term Management of Petroleum-Contaminated Soil and Groundwater.   (see PDF file) ...
 

9.6 Methamphetamine Laboratory Cleanup
...if residues enter the heating, ventilation and air-conditioning system. Soil or groundwater may become contaminated if chemicals are disposed of in a septic system or dumped outside. ...
 

Appendix 9-B Initial Shortlist of Pesticides Used in Sugarcane and Pineapple Operations
... Herbicide with low to moderate persistence (beaks down in water). Heptachlor ...
 
... 1 Montgomery, J.H. 2000. Groundwater Chemicals. Desk Reference (3rd Ed). ...
 
... 8 Knisel & Davis. 2000. Groundwater Loading Effects of Agricultural Management Systems. ...
 

Appendix 9-B Initial Shortlist of Pesticides Used in Sugarcane and Pineapple Operations
... ● If no KoC was available, but water solubility was high, pesticide was assumed to have high mobility. ...
 

Appendix 9-D Guidance Fact Sheet for Use When Petroleum Contamination is Encountered
...oil which when released into the environment causes a sheen to appear on surface water, or any navigable water of the State. Any free product that appears on groundwater. ...
 
...or any navigable water of the State. Any free product that appears on groundwater. Any amount of ...
 
...of the State. Any free product that appears on groundwater. Any amount of oil released to the environment greater than 25 gallons. Any ...
 
...or disposed of appropriately. Petroleum-contaminated water encountered during dewatering projects must be tested and treated as necessary prior ...
 
...encountered during dewatering projects must be tested and treated as necessary prior to discharge into a storm ...
 
...prior to discharge into a storm drain or other pathway that leads to surface water bodies. At a minimum, this will usually require that the water be passed through an ...
 
...bodies. At a minimum, this will usually require that the water be passed through an oil/water separator. The water should also be tested for dissolved-phase ...
 
...be passed through an oil/water separator. The water should also be tested for dissolved-phase petroleum contaminants ...
 
...separator. The water should also be tested for dissolved-phase petroleum contaminants prior to discharge ...
 
...petroleum contaminants prior to discharge (at least initially). The water should be treated to meet HDOH Environmental Action Levels for discharges to surface ...
 
...be treated to meet HDOH Environmental Action Levels for discharges to surface waters or a more site-specific assessment of potential impacts to aquatic habitats carried ...
 
...Hazard Evaluation (EHE) guidance can be consulted for applicable surface water environmental action levels, or call the HEER Office (808) 586-4249 during business ...
 
...(808) 586-4249 during business hours for assistance. Groundwater Management: Groundwater that contains free product or a sheen can ...
 
...Management: Groundwater that contains free product or a sheen can assumed to be contaminated with dissolved ...
 
...disposal, or discharge are all acceptable options for the disposition of groundwater generated during subsurface excavation that encounters contaminated groundwater. Of ...
 
...generated during subsurface excavation that encounters contaminated groundwater. Of these choices, re-infiltration within the Work Area where the water was extracted ...
 
...Of these choices, re-infiltration within the Work Area where the water was extracted is the least expensive and easiest way to manage contaminated groundwater; ...
 
...was extracted is the least expensive and easiest way to manage contaminated groundwater; however this option may not be feasible at all project locations. ...
 
... at all project locations.   Groundwater should be reused within the Work Area and within the same aquifer where it ...
 
...and State permit requirements. If discharged to storm sewers or surface water bodies: National Pollution Discharge Elimination ...
 
...System and State permit requirements also apply. Prior to dewatering, clearance and/or permits from the CWB are required. Removal of floating ...
 
...from the CWB are required. Removal of floating product via an oil water separator and/or passage of the water through settling ponds or sand ...
 
...separator and/or passage of the water through settling ponds or sand filters may not be adequate to reduce ...
 
... At a minimum, all groundwater discharged to storm sewers must be analyzed for constituents ...
 
... the vicinity of the work area. The groundwater must be analyzed for known or suspected contaminants and the results ...
 
... must be screened against the Estuarine EALs for Surface Water Bodies, in Table D of Volume 1 of Screening for Environmental ...
 
...Hazards at Sites with Contaminated Soil and Groundwater, Fall 2011 Updates, Revised January 2012 (and updates) For some ...
 
... The trench must be within the Work Area, especially if the groundwater is extracted from a Work Area in the vicinity of known or observed ...
 
...for well construction, placement, use, and closure. In instances where �oily water� is disposed, the receiving facility must be permitted for that type of waste. ...
 

5.10 Investigation Derived Waste
... Soil cuttings from drilling or hand augering; Drilling mud or water used for mud or water rotary drilling; Decontamination wash water, rags, ...
 
...used for mud or water rotary drilling; Decontamination wash water, rags, towels, etc.; Spent ...
 
...rotary drilling; Decontamination wash water, rags, towels, etc.; Spent solvents used in sample preparation (e.g., ...
 
...material, the volume should be minimized and mixing of waste solvent with detergent/wash water mixes avoided. Management and disposal of waste groundwater generated during developing ...
 
...mixes avoided. Management and disposal of waste groundwater generated during developing and purging activities is discussed in Section 6 and summarized ...
 
... activities is discussed in Section 6 and summarized below. Development and purge water can be disposed of on the ground immediately downgradient of the well provided that it is generated ...
 
...downgradient of the well provided that it is generated from the uppermost groundwater unit, is not impacted above action levels applicable to the site, does not contain free product ...
 
...not contain free product or exhibit a sheen, and is not allowed to runoff into a surface water body or storm drain (refer to USEPA 2014). If these criteria cannot be met then the ...
 
...or storm drain (refer to USEPA 2014). If these criteria cannot be met then the water must be disposed of at an offsite, regulated facility (e.g., municipal landfill or other treatment ...
 
...facility (e.g., municipal landfill or other treatment facility). Development and purge water should not be disposed in monitoring wells. Non-hazardous IDW such as drill cuttings, drilling ...
 
...wells. Non-hazardous IDW such as drill cuttings, drilling mud, purge or development water, decontamination wash water, etc., should not be disposed of in dumpsters. [Note that guidance ...
 
...decontamination wash water, etc., should not be disposed of in dumpsters. [Note that guidance presented above replaces ...
 

8.4 Field Screening Methods for Selected Contaminants and Media
...Dye Test Method: Soil is added to a sample bottle with water and a rapidly dissolving red or blue oleophilic dye. Contents are shaken vigorously. Released ...
 
...false negative results. Limitations: Water in the sample above 2% will cause low readings and cause a noticeable reaction with ...
 
...for this purpose. The sample is placed in a glass vial with organic-free reagent water, shaken, and a photoionization detector (PID) is used to measure the volatile organics ...
 
...(PID) is used to measure the volatile organics found in the headspace over the sample/water mixture. This method may be especially suitable for screening of low levels of chlorinated ...
 
... USEPA 4015 (USEPA, 1996t): Screening for 2,4-D in Soil or Water by Immunoassay Method: The method is performed using an extract ...
 
...present at concentrations above 0.1, 0.5, 1.0 or 5.0 mg/kg in soil, and 10 μg/L in water (ground water monitoring). Advantages: Samples can be analyzed quickly ...
 
...(ground water monitoring). Advantages: Samples can be analyzed quickly and on-site. ...
 
... USEPA 4670 (USEPA, 2007j): Triazine Herbicides as Atrazine in Water by Quantitative Immunoassay Method: This method uses a competitive ...
 
...This method uses a competitive immunoassay for the quantitative determination in water of triazine herbicides as atrazine. The method is performed using an aliquot of the water ...
 
...of triazine herbicides as atrazine. The method is performed using an aliquot of the water sample and an enzyme-atrazine conjugate reagent, which are added to an immobilized atrazine ...
 
... Target Analytes: Method 4670 is a procedure for screening water with an optimal quantification limit of 0.03 μg/L for drinking water samples. The actual ...
 
...with an optimal quantification limit of 0.03 μg/L for drinking water samples. The actual method sensitivity may be highly dependent on the kit used and sample ...
 
... USEPA 4010A (USEPA, 1996u): Screening for Pentachlorophenol (in Soil and Wastewater) by Immunoassay Method: Method 4010A is a procedure for screening ...
 
...procedure for screening solids such as soil and sludge and aqueous media such as wastewater and leachate for pentachlorophenol (PCP) (CAS Registry No. 87-86-5). The method ...
 
...pentachlorophenol (PCP) (CAS Registry No. 87-86-5). The method is performed using a water sample or an extract of a water sample. The sample/extract and an enzyme conjugate reagent ...
 
...sample or an extract of a water sample. The sample/extract and an enzyme conjugate reagent are added to immobilized antibody. ...
 
...An aliquot of the filtered methanol extract is added to acidified HPLC-grade water and the mixture is loaded onto a solid-phase extraction (SPE) column and eluted with hexane. ...
 
...extraction (SPE) column and eluted with hexane. The hexane eluate is mixed with basic water and is shaken. The aqueous solution is poured into a vial containing acidic water, octane, ...
 
...and is shaken. The aqueous solution is poured into a vial containing acidic water, octane, and cobalt chloride to facilitate separation. The mixture is shaken and allowed ...
 

8.5 Field Screening With Cone Penetrometer and Sensors/Probes
...sensors/probes on on direct push platforms (DPT) can be used to delineate a water table and even to predict where vertical gradients could be present. Other types ...
 
...The devices developed for these platforms are: samplers for soil, soil gas and groundwater; geotechnical sensors for soil texture and hydraulic conductivity; and chemical sensor sampling ...
 
... collected from the site. Conductivity varies with grain size but also with soil water content and ionic strength of the pore water or groundwater. Ionic strength of the groundwater ...
 
...content and ionic strength of the pore water or groundwater. Ionic strength of the groundwater can change due to contaminant content. Dense ...
 
...or groundwater. Ionic strength of the groundwater can change due to contaminant content. Dense non-aqueous ...
 
...Ionic strength of the groundwater can change due to contaminant content. Dense non-aqueous phase liquids (DNAPL) have a very ...
 
...locating LNAPL plumes (USEPA 2005). Because conductivity is influenced by soil type, water saturation, solute type, solute concentration and presence of non-aqueous phase liquids, the ...
 
...used to determine the hydraulic conductivity of subsurface soils and the depth to groundwater. These data can be used to identify potential contaminant pathways in the subsurface, or to ...
 
...systems for the detection of volatile organic compounds in soil and groundwater (USEPA 2004 and 2005). USEPA evaluation of chemical sensors used with CPT has ...
 
...for real-time, in situ, field screening of hydrocarbons in subsurface soil and groundwater. The technologies are intended to provide highly detailed, qualitative to semi-quantitative ...
 
...to volatilize and mobilize contaminants for sampling. Heating the soil and/or groundwater adjacent to the MIP�s semi-permeable membrane volatilizes the VOCs, which then pass ...
 
...the membrane to 80 to 125 �C (160 to 232 �F), which allows VOCs in the soil and groundwater to partition across the membrane in saturated or unsaturated soil. The subsurface temperature ...
 
... the surface. Typically, the MIP probe includes a tip that measures soil or water conductivity at a known distance below the membrane. The conductivity measurements can ...
 
...soil�s electrical behavior that can be related to changes in stratigraphy or groundwater quality. Analytical devices commonly used with an MIP include gas chromatography (GC)-grade ...
 
...screening-level data that need to be supplemented with analytical soil or groundwater data to fully support human health risk assessments or remediation decisions. ...
 

8.6 Field Screening Equipment to Support Health and Safety Programs
...industrial hygienist. Weather conditions such as extreme heat or cold, humidity (water vapor), exposure to rain or other spilled liquids, and electromagnetic radiation can all affect ...
 
...discussed in the following subsections are typically used during soil and groundwater investigations. Additional air monitoring, radiation monitoring or other specialized equipment ...