NYSDEC Proposes Updates To Commissioner's Policy 51 – Soil Cleanup Guidance

For the first time in over a decade, NYSDEC proposes to update Commissioner's Policy 51 (CP-51), which sets forth the soil cleanup levels for the NYSDEC Division of Environmental Remediation's remedial programs, including the Inactive Hazardous Waste Disposal Site Remedial Program (State Superfund Program), Brownfield Cleanup Program (BCP), Voluntary Cleanup Program (VCP), Environmental Restoration Program (ERP), the Spill Response Program under Article 12 of the Navigation Law, and the Resource Conservation and Recovery Act (RCRA) Corrective Action Program. NYSDEC will accept written public comments on the proposed CP-51 revisions until 5 p.m. on September 26, 2024. These proposed CP-51 revisions will be generally complimentary to the pending amendments to the 6 NYCRR Part 375 regulations (Part 375) that govern most NYSDEC remedial programs.

Once effective, the CP-51 revisions will, among other things:

• add soil cleanup guidance values for two per- and polyfluoroalkyl substances (PFAS) compounds (perfluorooctanoic acid [PFOA] and perfluorooctane sulfonic acid [PFOS]);
• establish "presumptive remedies" for polychlorinated biphenyl (PCB) cleanups and align NYSDEC guidance with federal requirements;
• supplement the regulatory and program policy guidance definitions of "grossly contaminated media" based on elevated concentrations of polycyclic aromatic hydrocarbons (PAHs);
• modify and/or eliminate certain supplemental soil cleanup objectives (SCOs) and petroleum-related unrestricted SCOs; and
• refine the criteria used to evaluate the potential degree of public health or environmental concern when a SCO is exceeded.

While the CP-51 revisions should not form the basis for modification of any previously approved remedy, the updated requirements may be applied to any remedy selected or approved by NYSDEC following the effective date of the revisions.

PFAS Guidance Values

NYSDEC provided "guidance values" under CP-51 for two PFAS compounds to be used until formal SCOs are established under Part 375. Additionally, NYSDEC is working to develop protection of ecological resources SCOs for PFAS but is proposing "screening values" under CP-51 to be used in the interim:

Other than those newly proposed screening values for the protection of ecological resources, the PFAS guidance values under CP-51 match those previously established by NYSDEC in its "Sampling, Analysis, and Assessment of Per- and Polyfluoroalkyl Substances (PFAS) under NYSDEC's Part 375 Remedial Programs" guidance document. Testing for PFAS should be included for all Target Compound List/Target Analyte List (TCL/TAL) analyses connected with requests to import soil for backfill, and the results compared to the lower of the applicable site-use or protection of groundwater guidance values.

Presumptive Remedies for PCBs

NYSDEC proposes presumptive remedies for PCBs consistent with EPA's regulatory requirements for self-implementing cleanups, which link PCB cleanup levels with the expected occupancy rates of the area under remediation. In contrast to risk-based remedies for PCBs, self-implementing cleanups for low-occupancy sites do not require the prior written approval of EPA. These presumptive remedies proposed by NYSDEC would be applied regardless of whether PCBs were released at a given site before or after 1978, when EPA banned PCBs under the Toxic Substances Control Act (TSCA).

For non-BCP sites where neither unrestricted nor protection of ecological resources SCOs apply, a presumptive PCB remedy may include remediation to 1 ppm in surface soils and 10 ppm in subsurface soils. For non-BCP residential use sites, a presumptive remedy may include remediation of PCBs to 1 ppm in all soils above bedrock, notwithstanding the other requirements of Part 375.

For BCP sites, the presumptive remedies for PCBs are as follows by cleanup track:

• Track 1 – Unrestricted: Soil cleanup to 0.1 ppm for all soils above bedrock.
• Track 2 & 3 – Residential, Restricted Residential, Commercial: Soil cleanup to 1 ppm for all soils above bedrock (as limited by other Part 375 requirements), where protection of ecological resources SCOs do not apply.
• Track 4 – Restricted Residential, Commercial, Industrial: Soil cleanup to 1 ppm in surface soils and 10 ppm in subsurface soils, where protection of ecological resources SCOs do not apply.

However, for industrial use sites that do not meet EPA's low-occupancy cleanup requirement (i.e., requiring site access controls and individual occupancy of fewer than 6.7 hours per week), the Part 375 industrial SCO of 25 ppm for PCBs will not satisfy EPA's self-implementing criteria. Therefore, such industrial sites may require a site-specific PCB remedy to be established instead of NYSDEC's presumptive remedy, or the review and approval of EPA of a risk-based cleanup.

PAHs as Basis for Grossly Contaminated Media Determination

Based on NYSDEC's experience with manufactured gas plant (MGP) coal tar and petroleum remediation, NYSDEC proposes to consider all subsurface soils with total PAH concentrations greater than 500 ppm to be "grossly contaminated media" as defined in "NYSDEC Program Policy, DER-10 / Technical Guidance for Site Investigation and Remediation" (DER-10). These grossly contaminated media must be remediated according to the relevant requirements of Part 375 and DER-10, and institutional controls such as an environmental easement and site management plan will be required for these sites.

Updates to Supplemental SCOs and Petroleum-Related Unrestricted SCOs

NYSDEC proposes to eliminate a number of supplemental SCOs derived from its former "Technical and Administrative Guidance Memorandum 4046: Determination of Soil Cleanup Objectives and Cleanup Levels" (TAGM 4046) policy document, dated January 1994, in Table 1 of the proposed CP-51 revisions. NYSDEC determined that these TAGM 4046-derived supplemental SCOs did not consider public health protection factors that are now widely recognized and will reevaluate them for potential re-inclusion in CP-51 in the future. Certain other supplemental SCOs included in Table 1 are proposed for modification and/or deletion, as the Department seeks to increase overall consistency in its methodology for establishing SCOs.

NYSDEC also proposes to update Table 2 of CP-51 to modify the unrestricted SCOs for gasoline-contaminated soils and Table 3 to modify the unrestricted SCOs for fuel oil-contaminated soils.

Refined Exceedance of SCO Evaluation Factors

Under the existing CP-51, NYSDEC provided four exemplary factors to evaluate the potential magnitude of public health or environmental concern resulting from the exceedance of a SCO at a site:

• magnitude of the exceedances;
• accuracy of the exposure estimates;
• other sources of exposure to the contaminant; and
• the strength and quality of available toxicological information about the contaminants of concern.

In the revisions to CP-51, NYSDEC proposes to refine these criteria to include the:

• number of samples that exceed applicable standards, criteria, or guidance;
• magnitude by which the concentrations exceed the applicable standards, criteria, or guidance, as presented in the investigation report;
• magnitude by which the concentrations exceed the site-specific background concentrations;
• potential for human or ecological exposure to contaminants present in any media;
• potential for a contaminant to migrate within or off of the site, or to partition into other media; and
• strength and quality of available toxicological information about the contaminants of concern.

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