SUPPLEMENTARY INFORMATION:

The NPL, created under section 105 of CERCLA, as amended, is an appendix of the NCP. The NCP establishes the criteria that EPA uses to delete sites from the NPL. In accordance with 40 CFR 300.425(e), sites may be deleted from the NPL where no further response is appropriate. Partial deletion of sites is in accordance with 40 CFR 300.425(e) and are consistent with the Notice of Policy Change: Partial Deletion of Sites Listed on the National Priorities List, 60 FR 55466, (November 1, 1995). The sites to be deleted are listed in Table 1, including docket information containing reference documents with the rationale and data principally relied upon by the EPA to determine that the Superfund response is complete. The NCP permits activities to occur at a deleted site, or that media or parcel of a partially deleted site, including operation and maintenance of the remedy, monitoring, and five-year reviews. These activities for the site are entered in Table 1 in this SUPPLEMENTARY INFORMATION section, if applicable, under Footnote such that; 1 = site has continued operation and maintenance of the remedy, 2 = site receives continued monitoring, and 3 = site five-year reviews are conducted. As described in 40 CFR 300.425(e)(3) of the NCP, a site or portion of a site deleted from the NPL remains eligible for Fund-financed remedial action if future conditions warrant such actions.

Information concerning the sites to be deleted and partially deleted from the NPL, and the proposed rule for the deletion and partial deletion of the sites, are included in Table 2.

For the sites proposed for deletion, the closing date for comments in the proposed rule was September 16, 2024. The EPA extended the public comment period for the proposed partial deletion of the Del Amo site until November 16, 2024. The EPA received five submissions for the Del Amo site, each with multiple comments. The EPA received no public comment for any of the other three sites in this final rule. The EPA prepared a Responsiveness Summary to address public comment for the Del Amo site partial deletion. The EPA placed the public submissions with comments and Responsiveness Summary for the Del Amo site in the docket specified in Table 1, on https://www.regulations.gov, and in the appropriate Regional Records Center listed in the ADDRESSES section.

Commenters for the Del Amo site expressed concerns that portions of the site proposed for deletion still contain contamination. The EPA believes the portions of the site proposed for deletion from the NPL does not contain contamination exceeding residential risk screening levels, and the EPA is proposing to delete only the portions of the site where all appropriate response actions are completed, and cleanup goals met. The EPA clarified which areas are included in the proposed deletion, whether the areas included in the area proposed for deletion were ( printed page 11220) studied during the Remedial Investigation, and what work was performed at those portions of the site to clean them up. Other commenters expressed concern about groundwater contamination and operating groundwater remedies. The EPA wants to make clear that the proposed partial deletion will have no effect on the groundwater remedy, which is part of the Dual Site Groundwater Operable Unit for the Montrose Chemical and Del Amo Superfund Sites. The proposed partial deletion includes surface and subsurface soils, but not groundwater, for specified areas of Operable Unit 1 of the Del Amo site. Commenters requested information about how the Building Permit Review Institutional Control Layer 2 (Building Permit Review) works and expressed concern about how the EPA will protect against contaminated dust from the soil in the deleted parcels during construction and redevelopment. The EPA explained Institutional Control Layer 2 (Building Permit Review) creates a process where building permits applications are reviewed by the Del Amo Environmental Review Team, who then prepares and submits a Screening Evaluation Summary Report. The Screening Evaluation Summary Report, which is reviewed and approved by the EPA, includes an evaluation of the potential for exposure to impacted material during performance of the construction project based on existing environmental data, locations and documented historic information concerning types of former rubber plant facilities and their operation, and findings from previously issued reports, as well as recommendations for mitigating risks as applicable. Commenters also expressed concerns that the Institutional Controls are insufficient to protect trench workers who may encounter contaminated soil at depth in the deleted portions of the Site. The EPA has investigated concentrations of chemicals of concern within the soil in the site area proposed for deletion and determined that concentrations of the chemicals of concern within the soil do not present a risk to human health or the environment under a residential use or worker scenario. In addition, out of an abundance of caution, Institutional Control Layers 1 and 2 will remain in place following the partial deletion. Keeping them in place helps ensure current and future owners and tenants are aware of the site's history. All these comments were carefully considered in the EPA's final decision to delete a portion of the Del Amo Site from the NPL. The EPA is proceeding with the partial deletion action as originally proposed.

Thus, the EPA concluded the deletion criteria for all four sites were met and documented in the specified dockets, and that the specified deletion actions from the NPL can proceed.

The EPA maintains the NPL as the list of sites that appear to present a significant risk to public health, welfare, or the environment. Deletion from the NPL does not preclude further remedial action. Whenever there is a significant release from a site deleted from the NPL, the deleted site may be restored to the NPL without application of the hazard ranking system. Deletion of a site from the NPL does not affect responsible party liability in the unlikely event that future conditions warrant further actions.

For reasons set out in the preamble, the EPA amends 40 CFR part 300 as follows:

90 FR 11218