Department of Health Seal

TGM for the Implementation of the Hawai'i State Contingency Plan
Section 19.3
CLOSURES WITH USE RESTRICTIONS

19.3 Closures with Use Restrictions

If contaminated media is left on site necessitating institutional or engineering controls to prevent potential future exposures, the site is closed with restricted use (i.e., a No Further Action with Restrictions or a Letter of Completion with Restrictions). The potential environmental hazards posed by leaving contaminated media on site must be assessed and documented in an Environmental Hazard Evaluation (EHE) (see Subsection 19.5). The mechanism to manage the environmental hazards posed by contaminated media left on site is called an EHMP (see Subsection 19.6).

A typical example of a restricted use closure is a petroleum-release site where petroleum-impacted soil cannot be fully excavated from the site (e.g., petroleum-impacted soil cannot be removed without jeopardizing structural integrity of a building). In the example, soil gas samples would need to be collected from beneath the slab, and resulting data may indicate a potential environmental hazard from subsurface vapor intrusion into indoor air spaces. The site may be closed with restricted use, but engineering controls (e.g., an active vapor mitigation system); institutional controls (i.e., an environmental covenant to restrict land use) may be necessary to prevent future exposures. An EHE would be required to assess potential hazards posed by the remaining petroleum contaminated soil. An EHMP would be required to document and manage the residual contaminated soil, engineering controls, and institutional controls. The EHMP typically would be attached to the closure document and, if applicable, the environmental covenant (see Subsection 19.8.1).

Another example of a restricted use closure is a case where only a land use restriction is required, with no engineering controls. This may be commonly 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 for commercial or industrial use. In this case, the site closure restriction would allow only a commercial/industrial use of the property, until such time as additional site investigation or site remediation demonstrates contaminant levels are below EALs for residential or unrestricted use. As noted in the example above, an EHPM typically would be attached to the closure document and, if applicable, the environmental covenant, to help document and manage the institutional controls at the site (e.g., the land use restrictions).

19.3.1 No Further Action with Restrictions

A restricted use closure under the Hawai`i SCP (HAR Chapter 11-451) is granted as a NFA with Restrictions. If the removal or remedial action has resulted in leaving contaminated media on site, the site closure is referred to as a "restricted use closure." An EHE must be prepared to document and assess environmental hazards posed by the remaining contaminated media. Institutional and/or engineering controls are necessary to prevent future exposures; therefore, future land uses are restricted. An EHMP is necessary to manage the residual contamination, engineering controls, and/or institutional controls.

19.3.2 Letter of Completion with Restrictions

A restricted use closure under the VRP (HRS 128D, Part II) is granted as a LOC with Restrictions. An EHE must be prepared to document and assess environmental hazards posed by the remaining contaminated media. Institutional and/or engineering controls are necessary to prevent future exposures; therefore, future land uses are restricted. An EHMP is necessary to manage the residual contamination, engineering controls, and/or institutional controls. Long-term (periodic) monitoring and reporting may be required to the HEER Office.

The LOC with Restrictions is noted on the property deed and is sent to the county agency that issues building permits. The restrictions on the LOC "run with the land" and apply to all future owners of the property.

HDOH may order a prospective purchaser receiving a LOC to re-open the site only if institutional or engineering controls that are part of the LOC are not being maintained, or contaminant concentrations are discovered at levels of concern (above Tier 1 EALs) for contaminants and media not listed in the LOC and VRP Agreement, or if a new release of contaminants and media listed in the LOC and VRP agreement occurs after the LOC is signed. HDOH cannot require prospective purchasers to perform additional work for contaminants and media covered in the VRP Agreement, as they have exemption from liability under HRS 128D, Part II.