Underground Storage Tanks

PIRI's (Partnership in RBCA Implementation) official members include representatives from the major oil companies (i.e., Amoco, BP, Chevron, Exxon, Mobil, and Shell), ASTM, EPA's OUST, and States. The paper presented here represents the points of view of the various PIRI authors and not the companies or states with which they are affiliated. This document is not an EPA document. This document will be updated as changes in technologies and policies require. It is critical that readers check with the implementing agency in their States before acting upon the policies discussed in these papers.

Since the development and publication of the American Society for Testing and Materials (ASTM) E 1739-95 Standard Guide for Risk-Based Corrective Action at Petroleum Release Sites and EPA's OSWER Directive 9610.17, Use of Risk-Based Decision Making in UST Corrective Action Programs, the majority of State UST programs have pursued some application of risk-based cleanup standards within their respective environmental programs. Regulators in numerous States have, however, voiced concerns that risk-based corrective action (RBCA) conflicts with the groundwater nondegradation policies of their agencies. As a result, the degree to which ASTM/RBCA can be successfully implemented has been limited in these States.

While virtually every State's environmental regulatory agency adheres to a nondegradation policy of some sort, the form, substance, and interpretation of these policies vary greatly. Usually found in the "Introduction" or "General" sections of the State's environmental protection act, nondegradation language can also be found in specific statutes or laws in the preambles and/or actual texts of the regulatory codes. Some States have no enforceable nondegradation language; rather, the agency has merely stated such a policy. Nondegradation policies can take the form of groundwater standards or classifications, of remedial goals or objectives and, in rare cases, of actual enforceable remedial standards. As a rule, the intent of nondegradation policies is usually to prevent pollution and to protect the viability of natural resources and not to establish "zero tolerance" cleanup standards. Through broad interpretation, though, some States have historically used nondegradation policies for just that purpose.

In attempting to deal with a nondegradation policy in the process of implementing a RBCA program in any State, the first step is to fully understand the intent and meaning of the policy. Is the policy being properly interpreted by the implementing agency? Who is interpreting it? Is the language being interpreted literally or has supposition been applied? Can all parties agree upon an official interpretation and application?

The next step is to determine if the policy presents a hurdle or a road block. How invested is the implementing agency in seeking a solution? There may be an opportunity to seek a more favorable interpretation, and there may be some flexibility in the agency's application of the policy. A number of approaches can be applied to successfully implement an ASTM/RBCA program in States with nondegradation policies.

Legislation/Rulemaking

The most direct approach to dealing with a nondegradation policy is to change it through legislation or rulemaking. This approach, however, should generally be pursued after other approaches have been exhausted. The processes of legislative change and environmental rulemaking are time-intensive and unpredictable.

Strict Interpretation

Assuming that a consensus interpretation of the nondegradation policy has not been achieved among the parties, the opportunity exists for them to agree on an interpretation more favorable to the RBCA process. For example, it can be argued that the intent of a nondegradation policy is to prevent the degrada- tion of a natural resource, and that once it becomes degraded other policies will have to be put in place to apply to the remedial efforts. This argument, however, should not be interpreted as a "license to pollute."

Standards Versus Objectives

In many cases, groundwater standards, cleanup standards, and cleanup objectives are considered synonymous. The most likely intent of groundwater standards is to protect the viability of potable aquifers and not to determine the level of cleanup necessary to apply to a contaminated aquifer. Groundwater standards may also serve to define classifications of groundwater. The argument should be made that not all groundwater is potable and that drinking water standards need only apply to aquifers which produce potable groundwater. Furthermore, there is a tremendous difference between objectives and standards. Arguably, cleanup standards should be set at realistically achievable levels commensurate with the risk posed by the contamination and the designated use of the aquifer, while cleanup objectives should represent targets or goals which might be technically, practicably, and financially unachievable.

Point Of Compliance

In the case of stringent generic cleanup standards, there may be an opportunity to apply the concept of risk by extending the point of compliance beyond the point of release. Many State codes allow for mixing zones. Also, many States base their cleanup standards on drinking water MCLs. By strict interpretation of the federal definition, MCLs apply only at the tap and not to the aquifer. Following this interpretation would allow for some flexibility to apply the principles of RBCA to the remedial effort.

Natural Attenuation

Although ASTM/RBCA applies the concepts of natural attenuation to the models that determine Tier II risk-based cleanup levels, there is still an opportunity to utilize natural attenuation in States that mandate strict concentration-based cleanup levels. Natural attenuation is one of many acceptable remediation options at UST sites. Please see the PIRI Issue Paper on natural attenuation for a discussion in greater detail.

Summary

There are certainly other approaches to dealing with nondegradation policies, probably as many as there are variations of the policies themselves. It is necessary for all involved parties to understand the intent and meaning of the policies and to develop a relationship that is conducive to seeking a solution. Finally, it is important to realize and understand that, notwithstanding their misinterpretation and misapplication, nondegradation policies are a vital part of an agency's environmental protection program. It should be the goal of all who endeavor to implement risk-based corrective action programs to achieve a balance between pollution prevention, exposure prevention and remedial action.

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