NPL
The NPL is EPA's list "of uncontrolled hazardous substance releases in the United States that are priorities for long-term remedial evaluation and response" (40 CFR 300.5). A release gets there by scoring high enough on the Hazard Ranking System or by one of two other routes in the regulation (40 CFR 300.425(c)). The regulation says what placement on the list does and what it does not do.
What puts a property on this record
The list is of releases, and the definition says nothing of property lines (40 CFR 300.5). In this regulation, "release also means threat of release" (40 CFR 300.5). A release may be included if it meets one of three sets of criteria (40 CFR 300.425(c)):
- It scores high enough on the Hazard Ranking System, EPA's method for rating the relative potential of releases to cause health, safety or ecological harm (40 CFR 300.5).
- A state, not including Indian tribes, designates it as that state's highest priority, and may make only one such designation.
- All three of these hold: a health advisory from the Agency for Toxic Substances and Disease Registry recommends separating people from the release, EPA determines that the release is a significant threat to public health, and EPA expects its remedial authority to be more cost-effective than its removal authority.
Lead agencies submit scored candidates, and EPA reviews them. The proposed and final rules are published in the Federal Register, with a public comment period on the proposal, and EPA updates the list at least once a year (40 CFR 300.425(d)). A federal facility that meets the criteria can be listed, but it is not eligible for Fund-financed remedial action except as CERCLA sections 111(e)(3) and 111(c) provide (40 CFR 300.425(b)(3)).
What a listing shows, and what it does not
It shows that EPA included the release under one of the criteria above, by that procedure (40 CFR 300.425(c), (d)).
The regulation states the consequence: "Only those releases included on the NPL shall be considered eligible for Fund-financed remedial action" (40 CFR 300.425(b)(1)). Removal actions are not limited to NPL sites (40 CFR 300.425(b)(1)).
It also states what listing does not do. "Inclusion of a release on the NPL does not imply that monies will be expended" (40 CFR 300.425(b)(2)). A release's rank does not fix the exact order in which Fund resources are spent (40 CFR 300.425(b)(2)). Listing is not a precondition to the lead agency acting under CERCLA section 106 or 122, nor to recovering costs under section 107, other than Fund-financed remedial construction costs (40 CFR 300.425(b)(4)).
The sections that define the list and place releases on it say nothing about the contaminants, extent, present condition or remedy status of a listed release, or whether it has reached another property.
In a Phase I ESA
The NPL site list is a standard government record source with an approximate minimum search distance of 1.0 mile (1.6 km) (E1527-21, 8.2.2, Table 2). The standard does not allow this list, or the RCRA treatment, storage and disposal records, to be searched at a reduced distance (E1527-21, 8.2.2).
If the subject property or an adjoining property is listed, the standard says the agency's file on the listing should be reviewed, to help the environmental professional judge whether the listing means a recognized environmental condition, a controlled or historical one, or a de minimis condition at the subject property. If the professional skips that review, the report must say why. Other records, or interviews with regulatory officials, may stand in, with a summary and an opinion on whether they suffice (E1527-21, 8.2.3.1, 8.2.3.2).
At the subject property, the answer turns on what the release is, where the file places it and where it has gone, and what has been done about it. The site inspection report, where one was prepared, describes the known contaminants and their pathways of migration (40 CFR 300.420(c)(5)). Where a remedy was selected, the record of decision says whether hazardous substances, pollutants or contaminants are to stay at the site so that a review at least every five years is required (40 CFR 300.430(f)(5)(iii)(C)). For controls, see activity and use limitations. The report states what the file establishes, with the professional's opinion on which class of condition, if any, applies (see REC, CREC, HREC or de minimis condition).
For a nearby listing, the standard's nonmandatory appendix lists factors for likely presence at the subject property that include where the source lies and the topography, geology and hydrogeology (E1527-21, X4.1). See likely release and likely presence and adjoining or nearby property. If the file cannot be had, see agency file review.
For every listing of the subject property or of another site inside the search distance, the report must give the professional's judgment on what the listing means for the analysis of recognized environmental conditions at the subject property, and one statement may cover several sites (E1527-21, 8.1.10).
What the federal rule says
Records of NPL sites or tribal- and state-equivalent sites (one mile);
40 CFR 312.26(c)(1)(i), edition revised as of July 1, 2025
The rule also lets the environmental professional modify a search distance, with the rationale documented (40 CFR 312.26(d)). The standard does not allow the NPL distance to be reduced (E1527-21, 8.2.2). The rule provides that the standard may be used to comply with 40 CFR 312.23 through 312.31 (40 CFR 312.11(a)).
Where the record is kept
EPA publishes the NPL and site profiles (documents, remedy status, contaminants) on its Superfund site search. The underlying inventory is SEMS. Data vendors resell the list geocoded in radius reports.
This page is general reference for environmental professionals. It does not classify any property. ASTM E1527-21 is the standard and is not reproduced here; the judgment of the environmental professional on the facts governs.
Classifying a finding
Situations in which this record type bears on the answer: