De Minimis Settlements Under Superfund

  • Recommendation number: 92-9
  • Adopted on: December 11, 1992
  • Publication Date: December 11, 1992

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In the last decade, following the passage in 1980 of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA),1 commonly referred to as Superfund, the nation has begun focusing its attention on the cleanup of hazardous waste sites. The task is a daunting one. There currently are approximately 1200 sites on the National Priorities List (NPL), the list of most hazardous sites, and it is likely that many more will be added to this list in the coming decades. The average cleanup cost at each of these sites is about $25 million. The aggregate cost of remedying the hazardous waste problem has been placed at several hundred billion dollars.

Joint and several liability for these clean-up costs has been imposed on a very broad set of parties—practically any party that had any connection with hazardous substances placed at a site in need of a cleanup, as well as owners and operators of contaminated facilities. Potentially responsible parties, known as PRPs, at typical Superfund sites include not only large industrial firms, but an array of small entities. Under the governing contribution rule, responsibility does not depend on the size of the firm, but rather depends generally on the firm’s hazardous waste contribution at the site.  Some PRPs therefore bear a large share of the liability at a site because they generated a large proportion of the hazardous substances. Other PRPs, which generated a relatively small proportion, may be responsible for only a few thousand dollars in cleanup costs. The process for apportioning the cleanup costs at a site gives rise to substantial transaction costs, principally legal fees and technical consulting costs. Parties that are responsible for only a small share of the cleanup costs might have to disburse several times this amount in transaction costs.

Congress expressed concern about this situation in 1986 when it reauthorized the program and substantially amended the statute. The Superfund Amendments and Reauthorization Act of 1986 (SARA),2 included provisions designed to make it easier for such “de minimis parties” to enter into early settlements with EPA, thereby limiting their transaction costs.

SARA set forth a far-reaching scheme for imposing liability for the cleanup of hazardous waste sites. The liability provisions are triggered by the release or threat of release of hazardous substances into the environment. For each site, the statute establishes four categories of liable parties: The generators of the hazardous substances present at the site, the transporters of these substances to the site, the current owner of the site, and prior owners during whose period of ownership there was disposal of hazardous substances at the site.3 These parties are liable for the costs of cleanup of the site, as well as for damage to natural resources under the control of the Federal or state governments, or Indian tribes.4

The language of the statute has the effect of imposing a strict liability rather than a negligence standard. Moreover, current law holds parties jointly and severally liable if the harm at the site is indivisible. Under the statute, PRPs held jointly and severally liable can seek contribution from other PRPs. The existence of joint and several liability is significant in the Superfund context because, given the significant periods of time—often several decades—between the disposal of hazardous substances and the cleanup, it is particularly likely that some liable parties will not be found, or will be insolvent. The remaining PRPs will then have to bear a disproportionate share of the costs.

The statute provides a limited set of defenses. Generally, a party can escape liability only if it can show by a preponderance of the evidence that the release or threat of release was caused solely by an act of God, an act of war, an act or omission of a third party, or a combination of these causes.  Only the third-party defense has been of practical significance. In addition to showing causation by a third party, a PRP seeking to escape liability must show that (i) it took due care with respect to the hazardous substances, (ii) it took precautions against foreseeable acts or omissions of the third party, and (iii) such acts or omissions did not occur in connection with a contractual relationship with the PRP.  So, for example, a generator cannot escape liability simply by showing that the problem was caused by the transporter with which it contracted for the disposal of the wastes.

To understand the context for de minimis settlements, it is important to review both the process of cleanup of hazardous waste sites and the allocation of responsibility for this cleanup among EPA and the PRPs. One of the most compelling reasons for offering early settlements to parties who bear only a small share of the liability is the very long time (averaging 12 years) that elapses between the discovery of a site and its ultimate cleanup. Settling with de minimis parties relatively early in this process can save them substantial legal and consulting costs.

The allocation of responsibility between EPA and the major PRPs at a particular site is also of critical importance. Many of the issues raised by a de minimis settlement concern its effect on subsequent settlements pursuant to which the major parties agree to undertake the cleanup of the site.

The early stages in the Superfund process involve the screening of sites to determine which pose the most serious health problems, and should therefore become the focus of EPA’s attention. The later stages involve the cleanup of these sites. Obviously, the call for de minimis settlements during the early stages of the process is more compelling because the process is a slow one.

Congress translated these concerns into statutory provisions encouraging settlements in general5 and de minimis settlements in particular.6  With regard to de minimis settlements, the statute provides that “whenever practicable and in the public interest.” the Administrator” shall as promptly as possible reach a final settlement with a potentially responsible party if such settlement involves only a minor portion of the response costs at the facility.” In addition, to qualify for de minimis status, generators and transporters must show that the amount and the effect of their hazardous waste contribution are both minimal in comparison to other hazardous substances at the facility.

Landowners constitute a unique class of PRPs. They may invoke an “innocent landowner” third-party defense to escape liability if they can establish they (i) “did not conduct or permit the generation, transportation, storage, treatment, or disposal of any hazardous substance at the facility,” (ii) “did not contribute to the release or threat of release of a hazardous substance at the facility through any act or omission,” and (iii) purchased the property without “actual or constructive knowledge that the property was used for the generation, transportation, storage, treatment, or disposal of any hazardous substances.”  If they elect, instead of pursuing this defense, to limit their liability by a settlement, they may do so. Since such settlements are entered into under the statutory provisions applicable to do minimis settlements, these landowners are customarily referred to as “de minimis landowner” PRPs.

This recommendation identifies several procedural steps that can be taken by the Environmental Protection Agency to improve the functioning of the de minimis settlement program.

As a general principle, EPA should establish procedures and incentives to negotiate de minimis settlements as a standard practice at all multi-party Superfund sites involving de minimis parties. The Conference’s study indicates the vast majority of de minimis settlements have been entered relatively late in the process, and the majority of the regional offices have shown little interest in undertaking earlier settlements. They frequently have favored resolving the liability of de minimis parties as part of global settlements pursuant to which the major parties undertake cleanups by requiring de minimis parties to negotiate directly with the major parties to determine their contribution to the cleanup cost. Paragraph 1 expresses the Conference’s belief that transaction costs can be reduced significantly by settling with de minimis parties rather than seeking de minimis settlements as part of a global settlement.

The predominant approach to de minimis settlements taken by EPA regional offices has been to wait for groups of de minimis parties to form and take the first step in proposing settlements. However, the formation of such groups requires the expenditure of transaction costs by private parties and can take considerable time, and such group might not represent the smaller de minimis parties that have the greatest interest in settlement. Paragraph 2 recommends that EPA’s regional offices take a more active role in seeking such settlements. The Conference also recognizes, however, that reasonable limitations on the negotiation process may be appropriate to avoid unduly protracted negotiations.

The study found significant differences in the approaches of the regional offices, and even across sites in the same region, due to the lack of concrete guidance on several important issues. Perhaps the most significant example is the variation in the volumetric determinant used to determine de minimis status. This lack of uniformity increases the incentives for parties to protest the terms of individual settlements, and increases the probability that such settlements could be successfully challenged in court. Paragraph 3(a) addresses this concern.

Paragraph 3(b) recognizes that, while current policy guidelines on de minimis landowner settlements contemplate some payment, they do not specify either how to compute this payment or its relationship to estimated costs of cleanup. Such guidelines are necessary because the current “innocent landowner” guidance does not provide any assistance to the regional offices in determining an appropriate settlement figure for such landowners.

Currently, settlement documents are dispersed throughout the regions, making it difficult to determine both the extent to which de minimis settlements are used and the content of the settlements reached. Assurance that similarly situated parties are treated similarly requires knowledge of what actual practice has been, and any efforts to standardize the practice would benefit from knowledge of the variants already employed. Paragraph 3(c) urges creation of a central repository of such documents to address this need.

The explanation given most frequently by the regional offices as to the impracticality of early de minimis settlements is the lack of sufficiently reliable information on cleanup costs. EPA’s recent guidance document has attempted to deal with this question on a regional level. Paragraph 4(a) suggests this task is better accomplished on the national level. In general, there is no reason for a regional office to confine itself to its own sites in determining the costs of similar cleanups, as the inventory of comparable sites that have progressed sufficiently in the cleanup process may be small or nonexistent. Furthermore, there is no central repository for de minimis settlement documents, which might contain relevant data, and no EPA database contains their full terms. While this information can generally be obtained from the individual regional offices, this process is cumbersome and time-consuming.

An element over which there is substantial conflict among EPA and the de minimis and major parties is the premium to be charged in exchange for a waiver of any cost overrun and the risk that future events may trigger the possibility of further action by EPA against a party that has already settled (“reopeners”). The study found wide variation, ranging from approximately 50% to 250%, not readily explained merely by the different stages at which the settlements were entered. Moreover, there does not appear to be a standardized method for calculating premiums. Paragraph 4(b), like paragraph 3(a), intended to reduce the potential for conflict by standardizing the approach.

In general, earlier settlements will be based on less accurate estimates of ultimate cleanup costs than settlement reached at later stages of the process. Paragraph 4(c) suggests that settlements, at the time they are reached, should represent a fair allocation of expected burdens.

The study found some evidence of confusion as to whether EPA can set up an account to finance a cleanup in cases in which it will not perform the cleanup itself and negotiations with the major parties are not sufficiently advanced. In these cases, the funds are generally placed in the Superfund and are not made available to finance a later cleanup by the major parties. These parties, understandably, object to this outcome, and the resulting friction is one of the reasons why several of the regional offices favor global settlements. Paragraph 5 suggests that EPA headquarters seek mechanisms to provide that an appropriate portion of the proceeds from de minimis settlements benefit the parties that take responsibility for the cleanup. Appropriate benefits might include amounts paid for future cleanup costs and premium payments.




1. EPA should make further efforts to establish procedures and incentives to negotiate de minimis settlements as a standard practice at all multi-party Superfund sites involving de minimis parties. EPA should not rely on global settlements as the preferred mechanism for resolving the liability of de minimis parties.

2. EPA’s regional offices should actively seek de minimis settlements by informing potentially responsible parties (PRPs) of their potential eligibility and circulating a draft settlement agreement as soon as the required statutory findings can be made.7 These steps should be taken as soon as is practicable, but in any event no later than the time EPA completes the “waste-in list,” which identifies the type and quantity of waste contributed to a site by each PRP. In undertaking settlement negotiations with de minimis parties, EPA regional office should be permitted to impose reasonable limitations on the negotiation process.

3. EPA headquarters should:

(a) Make further efforts to standardize the general terms of de minimis settlements and should establish a procedure to determine site-specific terms,

(b) Provide guidelines for the determination of appropriate payments and terms in de minimis landowner settlements; and

(c) Create and maintain a central repository of de minimis settlement documents, readily   accessible to the public.

4. To facilitate de minimis settlements, EPA headquarters should:

(a) Establish a database and methodology to assist and guide the regional offices in estimating site cleanup costs,

(b) Establish principles for determining premiums (additional fees charged to settling parties in exchange for immunity against reopening of their cases) applicable at different stages in the process, and

(c) Make clear that regional offices should seek settlements that, at the time of settlement, represent a fair allocation of expected burdens.

5. To enhance the acceptability of de minimis settlements, EPA headquarters should, to the extent permitted by law, establish mechanisms to ensure that the parties that take responsibility for the cleanup receive appropriate benefits from the proceeds of de minimis settlements.



57 FR 61766 (Dec. 29, 1992)

1992 ACUS 47 (vol 1)

1 Pub. L. No. 96-510, 94 Stat. 2767 (1980) (codified as amended at 42 U.S.C. §§ 9601-9675).

2 Pub. L. No. 99-499, 100 Stat. 1613 (1986). This law generally reflects the pro-negotiation approach urged by the Conference in Recommendation 84-4, “Negotiated Cleanup of Hazardous Waste Sites under CERCLA” (1984).

3 42 U.S.C. 9607(a). Under a limited set of circumstances a prior owner can be liable even if there was no disposal during its period of ownership. Liability will attach if the prior owner had actual knowledge of the release or threatened release when it owned the property, and transferred it without disclosing such knowledge. 42 U.S.C. 9607(35)(C).

4 42 U.S.C. 9607(a), (f)(1).

5 42 U.S.C. § 9622

6 42 U.S.C. § 9622(g).

7 See 42 U.S.C. 9622(g).


Kornhauser, Lewis A., and Richard L. Revesz.  De Minimis Settlements under Superfund.  1992 ACUS 691.