The Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA)¹ provides a detailed system for recovery for damage to natural resources that is caused by the release of hazardous substances. Previous federal statutes, such as the Trans-Alaska Pipeline Authorization Act,² the Deepwater Port Act,³ and the Outer Continental Shelf Lands Act Amendments of 1978,⁴ also have established liability for natural resource damages, but CERCLA reaches far beyond the narrow scope of those laws, addressing damage to fish, wildlife, and biota, as well as to air, land, and water, including groundwater and drinking water supplies.⁵ When a hazardous substance release injures or destroys natural resources, as in the case of groundwater contamination or a fish kill, CERCLA authorizes the federal or state governments to assert damage claims for those lost resources against the responsible party or against the statute's "superfund."⁶ CERCLA also mandates the promulgation of regulations for assessing the extent and value of such damage. Completing the resource damage recovery system, CERCLA provides that damage assessments made pursuant to these regulations shall have the force and effect of a rebuttable presumption on behalf of government claimants in a judicial proceeding against the responsible part or in an administrative proceeding against the fund.

The rebuttable presumption probably will be a significant concern of attorneys litigating the natural resource damage issue. Assessments made under CERCLA regulations about the extent and value of damage to natural resources are likely to be disputed vigorously by potentially liable parties because information about injury to or destruction of ecological and hydrological systems such as estuaries and aquifers probably will be both complicated and controversial. The assessment regulations and the rebuttable presumption may simplify claims proceedings. Moreover, on its face the rebuttable presumption appears to make it likely that the federal or state governments will prevail on their claims. However, because neither the statute nor its legislative history clarifies how to apply the rebuttable presumption in CERCLA cases, questions remain as to what effect it will have in judicial and administrative proceedings.