53 FR 37082-37247 Friday, Sept. 23, 1988 40 CFR Parts 280 and 281, Underground Storage Tanks; Technical Requirements and State Program Approval; Final Rules--Preamble Section IV. Analysis of Today's Rule--F. Release Response and Corrective Action for UST Systems Containing Regulated Substances
IV. Analysis of Today's Rule
IV. ANALYSIS OF TODAY'S RULE
F. Release Response and Corrective Action for UST Systems Containing Regulated Substances
Release response and corrective action for UST systems include activities to investigate, report, abate, and remedy releases of regulated substances into the environment. To ensure that necessary steps are taken to protect human health and the environment at all sites discovered to have a release, EPA proposed steps that all owners and operators must take quickly to identify and reduce any immediate health and safety threats posed by releases. In addition, proposed requirements mandated the investigation and amelioration of the long-term threats to human health and the environment posed by releases that have migrated beyond the UST system to contaminate surrounding soil and ground water. Long-term actions would begin after an implementing agency determined that additional corrective action was needed to protect human health and the environment. This determination was to be made on the basis of data gathered and submitted by the owner and operator and a site-specific exposure assessment performed by the implementing agency. Finally, the proposal distinguished between releases of petroleum and hazardous substances by establishing separate corrective action requirements for them in different sections of the proposed regulations (Subpart F for petroleum and Subpart G for hazardous substances).
Today's final rule builds upon this proposed approach, but also reflects several important changes that respond to concerns raised by commenters on the proposal:
o The Agency has consolidated the proposed requirements for petroleum and hazardous substances into one section of the final rule in Subpart F. This consolidation deletes the extensive duplication of requirements in the proposal caused by separating them into two sections.
o The proposed basic framework and most of the proposed requirements for the initial abatement steps required at all release sites are retained in the final rule. Changes have been made, however, to some of the proposed requirements in response to public comments. These changes are intended to clarify the owner's and operator's responsibilities for identifying and addressing the initial health and safety threats posed by releases.
o The final rule retains the proposed requirements for long-term corrective actions, which follow a site-specific approach for establishing clean-up target levels. This section of the rule has been amended, however, to clarify that the owner and operator may proceed, under certain conditions, with corrective action before a corrective action plan has been approved by the implementing agency.
o In response to concerns raised by several commenters, EPA has revised several of the proposed requirements to clarify the responsibilities of owners and operators. Some changes clarify when owners and operators must initiate specific corrective action steps, such as detailed soil and ground-water investigations, particularly in the absence of clear direction from the implementing agency. Other changes more clearly identify what owners or operators must do to carry out their responsibilities in such areas as the initial site investigation, detailed investigations for soil and ground-water contamination, and free-product removal.
o The final rule clarifies the requirements concerning the public participation process for corrective action. The final rule emphasizes the need to ensure public access (primarily through existing state procedures) to information pertaining to specific corrective actions.
In the preamble to the proposed UST corrective action rule, EPA requested comments on several corrective action issues: the general scope of the proposed requirements; how explicitly these requirements should be detailed in the rule; whether the proposed minimum site investigation requirements were appropriate; and the desirability of the proposed site-specific approach to setting cleanup goals for UST sites. EPA also requested comment on the definition of free product, the adequacy of existing state administrative authority for public participation in corrective action, and corrective action requirements for tanks containing a mixture of regulated substances (see 52 FR 12678-12683 and 12751-12757). EPA received comments on all these issues, as well as on other issues not raised specifically by the Agency in the proposal.
Although many commenters believed that the proposed corrective action regulations were essentially sound, EPA received a wide array of responses on key issues. For example, although several commenters disagreed with the Agency's proposed requirements for site-specific cleanup standards, others supported this approach. Several general concerns were repeatedly raised by numerous commenters as they commented on specific proposed requirements: what must be done and by whom, how much discretion should be granted to the implementing agency to change specific requirements, and what minimum objectives must be met during the various steps in the corrective action process. As noted previously, these general concerns have prompted EPA to make several changes in the final rule, and clarifications appear below in the following two subsections of today's preamble.
General concerns raised by commenters are briefly discussed and responded to in the next subsection of this preamble (section IV.F.2.):
o Site-specific approach to corrective action;
o Discretion for implementing agencies;
o Clarification of owner and operator responsibilities; and
o Consolidation of requirements for petroleum and hazardous substances.
Following the discussions of these issues, section IV.F.3. provides a section-by-section analysis that more specifically addresses the changes made to the proposed requirements in the development of today's final corrective action rule, and the highlights of the public response that prompted these revisions.
2. Major Issues Influencing the Final Rule
a. Site-Specific Approach to Corrective Action. In the proposed rule, EPA selected a site-specific approach for setting cleanup target levels for long-term corrective actions. These cleanup levels would be keyed to data obtained from a detailed site investigation of soil and ground-water contamination by the owner and operator, and from a site-specific exposure assessment conducted by the implementing agency. As discussed in the preamble to the proposal (52 FR 12680-12682), EPA believed this approach would allow implementing agencies the necessary flexibility to develop their own programs or implement existing programs. Given the size of the regulated community and the diversity of UST environmental settings, EPA concluded that the site-specific approach was the most effective framework for enabling implementing agencies to assess the extent of necessary corrective action in individual cases.
The final rule retains EPA's selection of the proposed site-specific approach for UST corrective action requirements. A central element of this site-specific approach is the establishment of site-specific cleanup standards that adequately protect human health and the environment. In the preamble to the proposed rule (52 FR 12678-12683), EPA asked for comments on whether the long-term cleanup requirements of the UST corrective action rule should be established: (a) On the basis of national cleanup standards, with a variance provision; (b) to reflect ground-water classification schemes where national standards would apply in some settings, and site-specific cleanup levels in others; or (c) as site-specific standards as proposed.
EPA received comments that supported each of these options, with suggestions on how to implement the preferred option. Most commenters who supported establishing national cleanup standards believed that standards expedite cleanups and provide greater consistency in cleanup goals. They did not provide EPA with information, however, that showed that the use of national cleanup standards would substantially hasten the UST corrective action process or relieve administrative burdens. In addition, EPA is not convinced that the use of a single cleanup standard for UST cleanups will achieve greater consistency in the protection of human health and the environment than a site-by-site exposure assessment approach. At the present time, the Agency's assessment of UST corrective action shows that cleanup results are generally limited by the available technology and particular site conditions rather than by a cleanup standard. EPA also believes that the site-specific exposure assessments for UST releases required in today's final rule can be streamlined so that they will not delay corrective action, as some of these commenters feared. The Agency intends to work with implementing agencies to develop methods to streamline site-specific exposure assessments without diminishing protection of human health and the environment.
Some commenters supported the use of a ground-water classification system for UST corrective action decisions. As discussed earlier in today's preamble, however, EPA has concluded that developing a classification system at the federal level is extremely difficult and unworkable. EPA leaves to the discretion of implementing agencies the choice of whether to establish or incorporate existing ground-water classification systems to assist in their UST corrective action decisions. The Agency notes that the required investigations at UST sites and a site-by-site approach for UST corrective action will likely incorporate many of the same factors used in establishing a ground-water classification system.
In developing today's final rule, EPA noted that the majority of commenters preferred the proposed site-specific approach. The primary reasons cited were that this approach best accommodates the diversity of UST release situations and also reduces, in the aggregate, the cost of compliance. EPA notes, however, that its decision to promulgate a site-specific approach to long-term UST corrective action does not preclude states from establishing cleanup standards in their own UST corrective action programs. The Agency recognizes that some states already have elected to develop and use statewide cleanup standards, sometimes in conjunction with site-specific exposure assessments as part of a variance procedure.
b. Discretion for Implementing Agencies. The proposed corrective action rule afforded UST implementing agencies considerable discretion and flexibility in developing their own UST corrective action process. For example, EPA proposed language--such as "unless directed to do otherwise by the implementing agency" and "or as directed by the implementing agency"--to indicate that these agencies could add their own requirements or instruct an owner and operator to bypass certain requirements on a case-by-case basis. EPA felt that the diversity of UST settings and release situations required the implementing agency to have flexibility in tailoring many aspects of the corrective action response so that different releases could be cleaned up effectively and efficiently.
EPA received comments regarding the appropriate level of discretion provided to the implementing agencies. Some commenters warned that vague rule language could lead to arbitrary requests by the implementing agency; others suggested that EPA curtail the implementing agency's authority by issuing more detailed requirements. Several commenters were concerned about delays in site cleanups that might ensue because of additional requests by implementing agencies. Another suggestion was to expand the implementing agency's discretion to require the UST owner and operator to start a site cleanup before a corrective action plan is finalized.
In response, EPA has revised the final rule to clarify which elements of the UST corrective action process are mandatory and which are discretionary. As a result, the final rule mandates the response requirements that must be followed for all releases (§ 280.61), the investigation and cleanup requirements that are mandatory unless otherwise directed by the implementing agency (§ 280.62 and 280.63), and the additional site-characterization and cleanup steps that may be required of UST owners and operators if certain site conditions exist or that may be required by the implementing agency (§ 280.64 through 280.66). EPA notes, however, that section 9008 of RCRA enables state and local regulation to be more stringent than the federal UST program. Thus, even if EPA removed discretion from the federal rules, EPA would not have the authority to prevent implementing agencies from imposing more extensive requirements than EPA under state or local law.
Commenters expressed concerns that cleanup of soil and ground water may be delayed due to lengthy reviews of the corrective action plans by the implementing agencies or by uncooperative owners and operators. In response, EPA has made two changes in the final rule. First, EPA has added the phrase "as appropriate" preceding the list of factors that the implementing agency must consider when reviewing a corrective action plan in § 280.66(b). This change makes it clear that the implementing agency need not formally consider all these factors if the agency determines analysis of these factors is not necessary to ensure protection of human health, safety, and the environment. Second, EPA has provided that owners and operators may begin cleanup of soil and ground water before their corrective action plan is approved by the implementing agency subject to conditions described in § 280.66(d).
In addition, under existing law, EPA or authorized UST implementing agencies can intervene to respond to clean up releases from UST systems. Under section 9003(h)(2) of RCRA, EPA and states under cooperative agreement are authorized to step in and take corrective actions for releases of petroleum from USTs in situations including the following: (1) the owner or operator fails to comply with the established cleanup schedule; (2) there is a need to take emergency action; (3) the cost of a corrective action exceeds the resources supplied by the financial responsibility mechanism provided by the owner or operator; or (4) the owner or operator is insolvent. For a release from a hazardous substance UST, EPA has the authority under CERCLA to respond. States are not provided such authority under CERCLA, but may have their own authorities under state law.
c. Clarification of Owner and Operator Responsibilities. Many commenters expressed the opinion that the proposed rule was difficult to interpret with respect to what had to be done and by whom to comply with the federal requirements. EPA agrees with these commenters that the language of the proposed rule was sometimes unclear regarding the specific responsibilities of UST owners and operators. The Agency, therefore, has revised the final rule to make clearer which elements of the corrective action rule are mandatory and which are discretionary.
EPA has concluded that the following basic steps are required to ensure an effective response to every release: rapid notification that a release has occurred; investigation to mitigate fire, explosion, and vapor hazards; preventing further release of the regulated substance from the leaking UST system; and removing free product from the environment. These steps are required of every owner and operator in response to an UST release; implementing agencies may not change these requirements.
Similarly, EPA believes that the following initial site investigation and abatement steps are usually necessary to protect human health and the environment: estimating the nature and quantity of the release; removing as much of the regulated substance from the UST system as necessary to prevent further release to the environment; and gathering information about the locations of wells, subsurface sewer lines, and populations surrounding the release site. Thus, the final rule holds UST owners and operators responsible for these actions unless the implementing agency directs them to do otherwise in response to site-specific considerations.
The baseline requirements for initial release response and corrective action are covered in § 280.61 through 280.63 of the final rule. As noted above, the requirements of § 280.61 in the final rule describe mandatory initial response measures to be taken by UST owners and operators without exception. All UST owners and operators are responsible for meeting the requirements of § 280.62 and 280.63, unless the implementing agency directs them to do otherwise. Sections 280.64 and 280.65 address those requirements for which owners and operators are responsible if certain site conditions exist. Section 280.66 describes soil and ground-water cleanup steps that may be initiated by the owner and operator or required at the direction of the implementing agency.
d. Consolidation of Corrective Action Requirements for Petroleum and Hazardous Substances. In the preamble of the proposed rule, EPA requested comments on whether the corrective action requirements for petroleum USTs (Subpart F) and hazardous substance USTs (Subpart G) should be integrated into one subpart or should remain separate (52 FR 12678). All commenters responding to this request favored the integration of Subparts F and G; they differed only in their suggestions to EPA on how to combine the two rules.
Today's final rule has consolidated into Subpart F all the corrective action requirements for releases from underground storage tank systems storing substances regulated by Subtitle I. The title of this subpart has been revised to make clear that it addresses both release response and corrective action activities. As can be inferred from the new title, an appropriate response to a release, particularly those small in size that were caught quickly and remedied, may not need to include long-term corrective action, if the initial response measures adequately protect human health and the environment.
The general applicability sections of the proposed petroleum and hazardous substance requirements (proposed § 280.60 and § 280.70, respectively) have been replaced with a single new section. This revised section states that where RCRA Subtitle C corrective action requirements apply to UST releases at permitted RCRA facilities, Subtitle I corrective action requirements will not apply. EPA has added this provision to avoid possible duplication of requirements.
The initial abatement requirements have been retained in the final rule. In response to commenters who preferred the more detailed language used in proposed Subpart G, the Agency has carried forward the language emphasizing immediate action to prevent further releases and the containment of visible releases to the environment. The principal change in the initial abatement requirements provides owners and operators and implementing agencies greater discretion for determining the need for and timing of contaminated soil removal and the authority to decide appropriate soil management alternatives on a site-by-site basis.
The proposed rule for hazardous substance USTs had no separate section comparable to the proposed petroleum rule's requirements for free product removal. By merging Subparts F and G, EPA extends the free product removal requirements to all regulated substance releases, including removal requirements detailing precautions and other measures to follow during recovery operations. EPA recognizes that detection and removal of some hazardous substances can be far more difficult than removal of petroleum free product, especially in areas of complex hydrogeology. The Agency believes, however, that the free product removal requirements allow implementing agencies sufficient flexibility to consider factors that complicate the detection and removal of free product and to adjust the pace of actions to remove free product accordingly.
Both proposed rules had requirements governing additional investigations and the cleanup of contaminated soils and ground water at UST release sites. The final rule also contains these requirements in § 280.65 and 280.66, which are discussed in more detail later in the next subsection of this preamble.
Both proposed rules contained reporting requirements. The hazardous substance rule, however, required additional specific reporting items, such as likely migration routes and proximity to population centers. These additional reporting items have not been retained in the initial site investigation requirements of Subpart F because they are largely duplicative of the reporting requirements contained within final § 280.63, which governs initial site characterization. Moreover, implementing agencies continue to have the authority to require the reporting of additional specific information should the need arise.
The public participation requirements of both rules have been combined into a single section of the final rule.
3. Section-by-Section Analysis
In writing the final rule, EPA revised proposed § 280.60 through 280.66 to clarify the release response and corrective action steps. Most of the changes are editorial, prompted by concerns or confusion expressed on the part of commenters. Some substantive changes, however, were also made in response to public comments. The following sections discuss in detail the changes made to the proposal as reflected in today's final rules. Issues raised by commenters on the proposed requirements and the Agency's consideration of these issues are also briefly discussed.
a. General (§ 280.60). Proposed § 280.60 applied the corrective action requirements of Subpart F to all UST systems except those exempted by statute or regulation. Owners and operators of tank systems for which other subparts of the proposed technical standard are deferred were nonetheless required to comply with the Subpart F requirements in response to confirmed releases.
In the final rule, EPA has added language to clarify the applicability of Subtitle C or Subtitle I requirements to USTs at RCRA-permitted facilities and to avoid potential overlap in regulatory authority. Section 280.60 of the final rule reflects the fact that the Subtitle C corrective action requirements under the authority of RCRA 3004(u) will apply to many releases from UST systems located at RCRA-permitted facilities, regardless of the regulated substance stored. For USTs not covered by 3004(u), including facilities without a final RCRA permit, Subtitle I corrective action standards will apply to releases from all petroleum and hazardous substance tanks covered under Subtitle I. UST corrective actions underway at facilities having interim status under RCRA may be subject to review under the RCRA corrective action program during the development of a final permit, and these ongoing corrective action activities may be incorporated into the facility's RCRA permit.
b. Initial Response and Reporting Requirements (§ 280.61). Proposed § 280.61 (initial abatement requirements and procedures) has been separated into three new sections in the final rule: initial response (§ 280.61), initial abatement measures and site check (§ 280.62), and initial site characterization (§ 280.63). These sections, plus free product removal (§ 280.64), encompass the first phase of the UST corrective action process. As with the proposal, EPA intends these final requirements to achieve three goals: (1) to bring UST release sites under control with respect to immediate health and safety hazards; (2) to stabilize the site so that contamination will not worsen as investigations and potentially applicable long-term cleanup plans are considered; and (3) to be self-implementing, in that these measures emphasize the responsibility of the owner and operator to take quick action without awaiting direction from the implementing agency. Thus, §§ 280.62 through 280.64 in the final rule represent the baseline release response and corrective action requirements that are mandatory for all UST owners and operators and all releases, unless the implementing agency directs otherwise. The rule has been reformatted to make this clearer. The initial response requirements of § 280.61 are mandatory for all owners and operators and all releases without exception. In addition, §§ 280.60 through 280.64 have newly added reporting sections. The new placement of these reporting requirements clarifies the owner's and operator's responsibilities with respect to the timing and content of the required reports.
The final requirements of § 280.61 for initial response and reporting are essentially identical to those proposed. The primary difference is that the wording has been changed to make unambiguous the response required within 24 hours. These initial actions include: reporting the confirmed release to the implementing agency; taking immediate steps to prevent further release to the environment; and mitigating fire, explosion, and vapor hazards. EPA recognizes that, in some cases, it may not be possible to complete these steps within 24 hours. For example, it is sometimes easier to confirm that a release has occurred than to identify the precise location of the release from the UST system. Similarly, it may take longer than 24 hours to adequately vent hazardous vapors from building. In revising this section, however, EPA emphasizes the potential urgency of a release and the responsibility of the owner and operator to quickly respond.
c. Initial Abatement Measures and Site Check (§ 280.62). In order to clarify the on-site management steps that EPA believes are necessary to abate hazards and stabilize the site, the Agency has grouped initial abatement requirements into § 280.62. Two of the requirements in this section are carried forward from those in proposed Subpart G. First, § 280.62(a)(1) requires removal of the regulated substance from the tank as "necessary to prevent further release to the environment." EPA has added this phrase to acknowledge--as some commenters pointed out--that some situations may not require complete removal of product from the tank (e.g., if the release is clearly demonstrated to be from one tank that is part of a multiple tank system). Second, § 280.62(a)(2) carries forward the requirement to visually inspect aboveground releases or exposed belowground releases and to prevent further migration of the released substance into surrounding soils and ground water (e.g., by using sorbents and berms to control the flow of product).
Section 280.62(a)(3) has been added to clarify EPA's proposed requirement to "mitigate fire and safety hazards." EPA agrees with commenters who noted that these hazards may persist or reappear beyond the initial response phase and, thus, must be monitored and remedied throughout the cleanup process. The new requirement also emphasizes that, if present, these hazards may require mitigation both within and beyond the boundaries of the UST site (e.g., in subsurface sewer lines or nearby buildings).
The requirement in proposed § 280.62(a)(4) to remove "visibly contaminated soil from the UST excavation zone" has been deleted. EPA received many comments on this proposed requirement. Most commenters expressed confusion regarding the definition of visible soil contamination and other concerns related to the appropriate timing and extent of soil removal. Commenters identified cases where a strict interpretation of the requirement (e.g., removal of slightly discolored soils) would translate into aggressive soil removal that would be unnecessary, technically infeasible, and very costly. Some commenters noted that extensive soil removal at UST sites could exacerbate problems of the nation's limited landfill capacity, if these soils were taken off-site for disposal. Other commenters suggested that soil removal or treatment (beyond that which is needed to address immediate health and safety hazards) should be considered as part of the long-term plan for corrective action. Many commenters suggested that EPA consider various in situ or on-site treatment methods as alternatives to immediate removal and disposal of contaminated soils.
EPA agrees with these commenters. In particular, EPA is concerned that requiring immediate and extensive excavation of contaminated soil may transfer contamination to other media (e.g., air), may transfer risk from one site to another, or may spread contamination at the release site beyond its existing extent. These outcomes are inconsistent with EPA's objective to protect human health and the environment. Further, EPA did not intend to preclude consideration of alternative on-site or in situ treatment methods.
As a result, EPA has created a new § 280.62(a)(4) to clarify the objectives of soil management that must be undertaken during the initial phases of corrective action. The new requirement states that UST owners and operators must remedy hazards posed by contaminated soils that are excavated or exposed as a result of release confirmation, site investigation, abatement, or corrective action measures. These hazards include vapor threats and potential leaching of contaminants. EPA believes this new requirement addresses concerns raised by commenters by more clearly stating the scope and the objectives of initial soil management.
In contrast to the proposed requirement for soil removal, EPA has not prescribed a specific management method. The final rule does, however, require that any exposed soils be managed as necessary to remedy hazards such as those mentioned above. EPA expects there will be UST release situations where prompt soil removal and disposal may be the most effective option (e.g., where there are relatively small quantities of contaminated soil in urban areas having high potential for human exposure to vapors, and where excavation equipment is already on-site for use in investigating the tank system). In such situations, soil removal may be necessary to bring the site under control with respect to immediate threats and might also be adequate to complete cleanup at the site. In response to commenter's concerns that soil management not simply transfer risk, EPA has, however, added a new requirement to the rule. If the owner and operator choose to treat or dispose of contaminated soils, they must comply with applicable state and local requirements. (See also section VI.B. of today's preamble: Relationship to Other Agency Programs.)
EPA received comments regarding the explicitness of the proposed site investigation requirements for corrective action, as well as for release confirmation and tank closure activities. Some commenters requested more specificity; others pointed out the difficulty of prescribing uniform requirements for all sites. In response, EPA has revised the rule (adding new §§ 280.52(b), 280.62(b) and 280.72(a)) to make consistent the site investigation requirements for release confirmation, corrective action, and tank closure and to avoid potential duplication of these requirements within the rule. (See section IV.E.2.c. of this preamble for an explanation of these site investigation requirements.) EPA believes this revised statement of site check responsibilities, in conjunction with the new initial soil management requirements, addresses commenters' request for greater clarity concerning their investigation responsibilities without unduly restricting alternative investigative techniques.
EPA recognizes, however, that the primary hazard posed by contaminated soil at some sites will be as a continuing source of ground-water contamination. EPA addresses this concern through the final requirements for site characterization and for delineating the extent and location of contaminated soils (§§ 280.63 and 280.65). As discussed later in this preamble, these investigation results must be considered by the owners and operators and by the implementing agency with respect to site-specific exposure potential and effects on ground-water resources. EPA believes that, in some cases, it may be preferable to treat contaminated soil on-site or in situ. The Agency is preparing technical information that will help owners and operators and implementing agencies assess the potential hazards posed by contaminated soils and alternative methods to treat or dispose of them.
Section 280.62(b) in the final rule states that owners and operators are required to report their initial abatement steps to the implementing agency within 20 days of release confirmation. Some commenters noted that this time frame, which was proposed in § 280.61(a)(5), could be interpreted to mean that EPA expected all the abatement measures in proposed § 280.61(a) to be completed within 20 days. EPA expects that many of the initial abatement requirements can and should be completed within 20 days, but that some aspects of soil management and free product investigations and removal may require more time to complete. EPA has thus amended the wording to clarify that the objective of this provision is to require owners and operators to report their progress to the implementing agency.
d. Initial Site Characterization (§ 280.63). Proposed as § 280.61(b), this requirement has been amended (and renumbered as § 280.63) to clarify the responsibility of owners and operators to collect and submit site information to the implementing agency. Several commenters noted that the same techniques can be used to confirm a release and to investigate contamination at a site. They expressed concern that important information gained while confirming a release or abating immediate hazards should also be included in the information submitted to the implementing agency. Section 280.63 in the final rule emphasizes this point and requires that owners and operators submit all pertinent information about the site and nature of the release.
In addition, §§ 280.63(a)(1) through (4) in the final rule describe the minimum site investigation requirements that the owner and operator must follow in the absence of other direction provided by the implementing agency. Section 280.63(a)(1) is unchanged from proposal, and it requires information on the nature and estimated quantity of the release.
Section 280.61(a)(2) continues to require owners and operators to submit information from readily available sources or site investigations regarding surrounding populations, subsurface soil conditions, climate, and land use (e.g., from sources such as U.S. Geological Survey maps, Soil conservation Saving maps, and local agencies). UST owners and operators are not automatically required to conduct surveys to collect this information if it is not already available.
In addition, two new requirements have been added to this section. First, information about water quality at all wells potentially affected by the release partially supplants the more general proposed requirement for ground-water and surface water sampling formerly in § 280.61(b)(3). As discussed in more detail in section IV.C.f. of this preamble--investigation for soil and ground-water cleanup--the proposed requirement to delineate the extent and location of dissolved ground-water contamination has been amended. The final rule requires full characterization of dissolved ground-water contamination if certain site conditions are met, or at the direction of the implementing agency. If nearby existing wells are potentially affected, however, EPA requires the owner and operator to immediately characterize their quality and use because they are potential human exposure points and because pumping at these wells can affect contaminant migration. Second, several commenters noted that subsurface sewer lines are often conduits for rapid migration of vapors or liquid product. Thus, EPA now requires owners and operators to submit information on the location of subsurface sewer lines (if any) at the site.
Section 280.63(a)(3) cross-references the site investigation requirements described earlier and requires the owner and operator to submit the results of this investigation as part of the site characterization report. This new section replaces proposed § 280.61(b)(2), which required sampling of surface and subsurface soils. As described earlier, this change clarifies the investigation requirements and eliminates their possible duplication within the rule. The timing and reporting of this investigation is unchanged.
Section 280.63(a)(4) replaces proposed § 280.61(b)(3), which required sampling of surface and ground water at the site. This new section, in conjunction with § 280.65 (described in subsection f., below), reduces the ambiguity noted by some commenters regarding the scope of site investigations. In the final rule, EPA requires characterization of dissolved ground-water contamination when the following conditions exist: there is evidence that drinking water wells have been affected, free product is detected on the water table or within the aquifer; there is evidence that contaminated soil is in contact with ground water; or as directed by the implementing agency. Thus, the presence or absence of free product at an UST release site is one of the factors used to decide whether further investigations of soil and ground-water contamination are necessary. The requirement to investigate for free product is unchanged from the proposed § 280.61(a)(6). The final rule simply requires owners and operators to submit, as part of the initial site report, their findings that establish the presence or absence of free product. EPA believes this action is warranted for several reasons:
o The requirement reinforces for owners and operators the importance of the free product investigation;
o The free product investigation requirement now also applies to releases from hazardous substance USTs, which may contain products that are denser than water and, therefore, may be harder to detect and locate; and
o The conclusion that no free product is found provides another important consideration for the implementing agency as it decides if a corrective action plan will need to be submitted by the owner and operator.
EPA believes this synthesis of information from the initial site investigation is essential for owners and operators to begin to fully assess their cleanup responsibilities, and it provides the implementing agency with information to decide if a corrective action plan is necessary. Section 280.63(b) replaces the proposed requirement for reporting site investigation results. The new section clarifies that the information must be submitted in a manner that is clear and sufficiently detailed to demonstrate its applicability and technical adequacy, or in a format developed by the implementing agency to achieve these same goals.
e. Free Product Removal (§ 280.64). In response to commenters, EPA has made minor revisions to the free product removal requirements. Commenters raised four issues: applicability, the definition of free product, the extent of removal, and the timing of removal. These issues are discussed below.
First, EPA agrees with those commenters who suggested that free product removal requirements similar to those proposed for petroleum releases should also apply to hazardous substance releases. The final rule's Subpart F merges the proposed rule's Subparts F and G to make free product removal requirements applicable to all releases.
Second, EPA has revised the definition of free product to clarify the scope of free product removal. Several commenters noted that, as proposed, the broad definition of free product could be interpreted to mean that removal requirements apply to product bound to soil particles or present as vapors. EPA notes that these forms of product are addressed, as appropriate, in other sections of today's final rule and has revised the definition of free product to more narrowly refer to a regulated substance that is present as a non-aqueous phase liquid (e.g., not dissolved in water). EPA has also deleted the reference to "floating" free product (from proposed § 280.62) to clarify that product more dense than water is also subject to the free product removal requirements.
Third, other commenters requested clarification on how much free product was required to be removed. In the final rule, the Agency has retained the phrase "maximum extent practicable" as the criterion for free product removal operations at UST release sites. EPA has not specifically defined maximum practicable removal because the extent of removal is largely determined by available technologies and site-specific conditions. Consequently, EPA believes that implementing agencies should have the discretion to develop operational criteria for determining the presence of free product and the extent of its removal (e.g., product that flows in response to gravity or a minimum product thickness observed in wells). EPA has, however, added to the final rule a minimum objective for free product removal operations. This new requirement states that, at a minimum, free product removal systems should be designed to abate further migration of free product (i.e., beyond small seasonal or recovery-related fluctuations).
Fourth, several commenters offered their views about the appropriate timing of product removal. Most commenters agreed with EPA's proposal that free product removal operations should begin as quickly as possible, but cautioned that hasty and improperly conducted removal could spread contamination vertically at the site. In the final rule, EPA continues to require that removal begin as quickly as practicable (§ 280.62(a)(6)). Revised § 280.64(a) emphasizes, however, that free product removal must be conducted in a manner that minimizes the spread of contamination and that is appropriate to the hydrogeologic conditions at the site. EPA is aware, for example, of site conditions where trenching or vapor extraction to recover free product would be preferable to drawing down the water table--and the free product plume--in order to collect and remove free product. EPA is preparing technical resource documents to assist implementing agencies in advising owners and operators about potential complications when removing free product. Similarly, in response to commenters concerns, EPA has extended the time period for owners and operators to report to implementing agencies concerning their free product removal from 30 to 45 days. This change will allow owners and operators more time to properly plan for free product removal, especially for removal operations involving dense product or at hydrogeologically complex sites.
In addition, some commenters requested EPA clarify permitting requirements for discharges from the product recovery system. Others suggested that EPA exempt UST cleanups from NPDES requirements or establish numerical limits for emergency permits. In response, EPA has revised § 280.64(a) to clarify that all discharges are to be properly treated, in compliance with applicable federal, state and local regulations. In addition, EPA is investigating methods to expedite, where applicable, the NPDES permitting process for discharges necessitated by UST corrective action.
f. Investigations for Soil and Ground-Water Cleanup (§ 280.65). Proposed § 280.63 has been renumbered § 280.65 in the final rule. As proposed, this section required the owner and operator to investigate the extent of soil and ground-water contamination at an UST release site when the initial site investigation showed that contaminated soil remained at the site, or when the required soil removal showed that the released product or product from contaminated soil may have reached ground water. In addition, the implementing agency could direct the owner and operator to conduct such an investigation.
Several commenters requested that EPA clarify the minimum sampling requirements for these investigations. Other commenters suggested that these more extensive investigations be better coordinated with the soil and ground-water sampling required earlier in the corrective action process. One commenter noted that the phrase "product from contaminated soil" would be difficult to define and might be interpreted to require extensive investigation at virtually all sites. In addition, EPA recognizes that some amount of contaminated soil will be present at most UST release sites, but that the threat posed by this contamination will depend on several factors.
In response to these comments, EPA has revised this section to clarify the situations that trigger more extensive site investigations. EPA notes that the objective of these investigations is to support decisions concerning whether soil and ground-water cleanup or other corrective action measures are necessary at the site. Consequently, EPA has revised the rule to better relate these requirements to site-specific threats to ground-water contamination.
Final § 280.65 describes three specific site circumstances requiring full for characterization of soil and ground-water contamination: (1) When release confirmation or previous corrective action measures indicate that ground-water wells may have been affected by the release, (2) when free product is found on the water table or within the aquifer, and (3) when any other site investigations show that contaminated soil may be in contact with ground water.
EPA recognizes that characterization of soil and ground-water contamination may also be necessary at sites where there are no "automatic triggers." Thus, the final rule retains the authority of the implementing agency to request an investigation. Final § 280.65(a)(4) clarifies that the implementing agency should consider the potential effects of contamination at the site in relation to nearby surface and ground-water resources when deciding whether further investigations are warranted. In particular, EPA expects that information required under § 280.63 will provide implementing agencies with important information for determining if more extensive investigations are required.
In revising the rule, EPA sought to better tailor the investigation requirements to site conditions that pose a potential threat to ground-water resources. EPA believes the final rule clarifies those situations that trigger more extensive site investigations and better coordinates the objectives of the revised corrective action requirements within a site-specific framework.
g. Corrective Action Plan (§ 280.66). In the final rule, proposed § 280.64 has been renumbered as § 280.66 and retitled as "Corrective Action Plan." This revised section responds to commenters' requests for clarification of the owners' and operators' responsibilities for submitting corrective action plans (CAPs) and of the implementing agencies responsibility to request, review, and approve a CAP. Subtitle I of RCRA directs the Agency to promulgate corrective action regulations applicable to owners and operators of UST systems. The corrective action plan approval process, however, integrates the responsibility of owners and operators to ameliorate the adverse effects of UST releases with the responsibility of implementing agencies to determine how they will carry out their established public health policies. EPA's role is to: (1) establish the responsibility of owners and operators to achieve adequate protection of human health, and (2) establish a baseline framework for evaluating and approving corrective action plans.
Several commenters requested clarification of the owners' and operators' responsibilities for corrective action beyond immediate abatement steps and removal of free product. In response, § 280.66(a) of the final rule has been revised to clarify that owners and operators are responsible for submitting, when requested by the implementing agency, a corrective action plan that provides for adequate protection of human health and the environment. Section 280.66(b) of the final rule sets forth the factors that implementing agencies must consider when approving a corrective action plan. Consequently, this section also serves to inform owners and operators of the minimum elements required in the plans they submit.
Some commenters suggested the Agency establish explicit criteria that implementing agencies could use to determine whether a CAP is needed and to evaluate CAPs after they are submitted. As described in the preceding sections, EPA has revised several parts of the proposed rule to clarify the objectives of each step of the corrective action process. Owners and operators are responsible for carrying out and reporting these actions, thus providing the implementing agency with a good basis for determining the necessity for additional cleanup.
EPA believes it would be difficult and unproductive to incorporate more explicit evaluation criteria in today's rule. As described earlier in this preamble, EPA received wide support for the proposed site-specific corrective action goals and has retained this approach in the final rule. Implementing agencies, however, may choose to develop their own site-specific corrective action goals, or they may base cleanup goals on statewide numerical standards or aquifer characteristics. Rather than develop criteria that may conflict with a state or local agency's preferred method, EPA has chosen to identify in the rule those factors that are generally necessary for carrying out corrective actions regardless of the chosen method for setting precise cleanup goals. For example, these factors include the persistence of the released substance and the hydrogeologic conditions at the site. EPA sees its role primarily as providing technical support for interpreting these factors in the context of site-specific application of corrective action technologies. In particular, EPA is developing technical information and supporting materials to assist implementing agencies in relating site assessment results to the feasibility of alternative technologies, and for evaluating how well these technologies are achieving cleanup at a site. In addition, EPA is beginning to develop methods to expedite exposure assessments. Other programs within EPA, such as the Office of Ground-water Protection, may also be called upon to provide support for evaluating ground-water resources.
The overall objective of longer term UST corrective actions is to adequately protect human health, safety, and the environment from contaminants remaining in soils or ground water after initial abatement measures and free product removal. The Agency prefers that this objective be achieved, where practicable, through reducing contaminant concentrations in soil or ground water to levels protective of health and the environment. In some situations, however, the Agency would require--under the standard in § 280.66(a)-- that human health be protected from exposure to contaminants through other appropriate measures, such as providing an alternative water supply.
EPA cannot project the outcome of its site-specific approach to all UST releases because the consideration accorded to some factors, such as aquifer resource value and its current and potential use, is largely left to state and local policy. If an UST release affects a public or private drinking water source, however, the owner and operator must expect that the state's health-based drinking water standards would apply to the cleanup. If the owner and operator cannot meet these standards through cleanup technologies, then they should expect that they will be required to provide an alternate source of drinking water or to provide treatment of the water to the people affected. Similarly, the owner and operator should expect that UST releases that threaten current or potential water supplies will come under close scrutiny by the implementing agency. In these cases, the corrective action requirements will likely be influenced by the mobility of the contaminants at the site and the estimated time and spatial extent over which the remaining contamination may pose a threat. At a minimum, approved CAPs would likely include requirements for long-term monitoring, continued control of ground-water flow at the site, and notice of continuing hazard in the property deed.
The final rule retains the implementing agency's authority to require submission of a CAP based on information received from early corrective action measures. (EPA expects, for example, that implementing agencies might choose this option for UST releases that are of great magnitude or in close proximity to drinking water resources.) Final § 280.66(a), however, has been revised to make clear that the implementing agency must first review the submitted material before requesting the submission of a CAP or additional information. This section also has been revised to enable owners and operators to submit a CAP for soil and ground-water cleanup based on their own initiative and assessment of the severity of the release. They need not wait for the implementing agency to request a CAP.
Several commenters expressed concern that lengthy reviews by the implementing agency might slow the pace of UST cleanups, creating delays that could make implementing the final CAP more difficult, because of the spread of contamination while delays persist. Some commenters also suggested that owners and operators should be allowed--after a specified length of time--to interpret inaction on the part of the implementing agency as approval of the CAP.
Given the number of releases that are expected to be detected in the near future, EPA acknowledges that there is potential for delayed cleanups under the proposed approach if implementing agencies are unable to review all the CAPs in a timely manner. The Agency concluded, however, that the alternatives suggested by commenters were inappropriate. To respond to this issue, however, § 280.66(d) has been added to allow owners and operators to begin cleanup of soil and dissolved contaminants in ground water without CAP approval provided they: (1) first notify the implementing agency of their intention to begin cleanup, (2) comply with modifications imposed by the implementing agency, including halting cleanup activities, and (3) incorporate these initial measures in the CAP to be reviewed and approved by the implementing agency.
EPA has added this provision with the goal of encouraging effective and expedited cleanup of soil and ground water. EPA emphasizes, however, that the implementing agencies remain the final arbiter for approving CAPs. Implementing agencies, therefore, can require the owner and operator to revise their CAPs and to modify the cleanup techniques in use at a site, including mitigating adverse consequences of cleanup activities. Since the implementing agency retains this authority, EPA expects that owners and operators who choose to initiate cleanup prior to approval of this CAP will select cleanup technologies that are widely used and recognized to be effective. EPA believes some cleanup techniques, such as extraction and treatment of petroleum vapors from soils, can be initiated with little risk of worsening contamination at the site. EPA also notes that states need not adopt the policy of owner- and operator-initiated cleanup for state program approval. Moreover, if states choose this option they can tailor its use to best meet their needs. For example, the implementing agency can identify specific cleanup technologies that are widely applicable without prior review or approval and those that always require explicit plan approval. Similarly, implementing agencies can decide to limit this option for use only at releases from certain USTs, such as petroleum USTs.
h. Reporting (Proposed § 280.65). The reporting requirements in this section of the proposed rule have been consolidated with the requirements in § 280.51 of the final rule because they are part of the release confirmation process.
i. Public Participation (§ 280.67). The proposed public participation rule required implementing agencies to provide opportunity for public review and comment on all CAPs and to consider these comments before approving CAPs.
Although commenters agreed that public participation is desirable, many commenters expressed concern that protracted public participation during the development of all CAPs could unnecessarily delay some UST cleanups. For example, cleanup efforts could be delayed while the development of a CAP was submitted to lengthy public review and deliberation. Also, mandating public participation for all CAPs could divert implementing agency resources from other cleanup activities such as oversight of ongoing cleanup operations.
EPA agrees with commenters who urged that implementing agencies strike a balance between the involvement of the public in corrective action decisions and the sometimes competing need to protect human health and the environment through quick and effective responses to an UST release. To acknowledge these sometimes conflicting objectives, the final rule for public participation establishes a flexible approach that ensures public access to available information on UST cleanups, although the public need not be involved, as a matter of routine, in all CAPs.
Implementing agencies continue, however, to have the responsibility and authority to notify the public about CAPs, to provide public access to the site and cleanup files, and to involve the public in meetings if sufficient interest is demonstrated. The final rule's public participation requirements for UST corrective action stress the need for adequate public notice, particularly to those parties who could be directly affected by the release and the planned corrective action. EPA expects that the public will be provided adequate opportunity to participate in and aid the UST cleanup process.
EPA does not agree with those commenters who opposed including any public participation requirements in the UST corrective action rule. In particular, EPA does not agree with the concerns raised that RCRA does not explicitly require public participation under Subtitle I. EPA believes that section 7004 of RCRA specifically mandates that all of the Agency's RCRA programs provide for the opportunity for public participation, including the RCRA Subtitle I program. This statutory mandate, combined with long-standing EPA policies to involve the public in the cleanup of contaminated sites, has prompted EPA's decision to keep the public participation requirements in Subpart F. In meeting this need, however, EPA has intended to require public notice and participation in UST corrective actions in a form that does not unnecessarily disrupt what state UST programs already require and provide.
The final rule requires public notification and public availability of information on CAPs. The implementing agency must notify the public about each confirmed release requiring a CAP. This notification requirement remains as proposed, although the rule no longer mandates implementing agencies to formally consider and respond to public comment before approving a CAP. The implementing agency must also provide public notice if implementation of the CAP does not achieve the established cleanup levels and the implementing agency is considering terminating the CAP. In most states, those affected by the release are often kept well informed through personal contacts with the state response staff. Today's requirements are not intended to change this practice of personal contact as one of the first points of public notice in the existing state UST programs. This method of notice has been added to the rule to make this clear. The list of public notice vehicles contained in the rule, however, is not intended to be exhaustive.
In addition to this notification requirement, the final rule requires the implementing agency to provide public access to site release information and decisions concerning the CAP. By providing public notification and access to information, implementing agencies ensure the opportunity for public participation in specific CAPs of interest to the affected sectors of the public. Because the Agency considers public notification and public access to information to be the key components of public participation for all CAPs, the final rule emphasizes the importance of these two requirements.
The implementing agency may hold a public meeting to consider public comments on a CAP if sufficient public interest is shown concerning a proposed CAP. EPA uses the phrase "public meeting" in the rule to emphasize that a formal public hearing is not required. EPA intends that a public forum be provided, in keeping with the state's administrative procedures, to inform the public and allow public comment on a CAP. The implementing agency will decide when public meetings are warranted on a case-by-case basis. EPA expects that large releases involving extensive corrective action will include correspondingly more extensive public participation because public understanding and acceptance is critical to the success of these CAPs.
In summary, the final rule emphasizes the implementing agency's responsibility to involve the public in a manner that best serves the environmental goals of the CAP.