HIGHLIGHTS OF PROPOSED REVISIONS. Technical Guidance Manual

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1 HIGHLIGHTS OF PROPOSED REVISIONS Pennsylvania=s Land Recycling Program Technical Guidance Manual Listed below are highlights of proposed revisions to PA DEP=s Act 2 Land Recycling Technical Assistance Guidance Manual. These were proposed in November, 2001 and are open for public comment. The revisions could be in effect by the first or second quarter of B. The Voluntary Nature of Act 2 Act 2 establishes the environmental remediation standards for cleanups related to certain environmental laws (Act 2, Section 106). Remediation, and the resulting liability relief under Act 2, Chapter 5, is specific to the contamination identified as part of a specific site or sites in the approved final report. Thus, there may be multiple sites on a property, or a single site may include all or part of one or more properties. If the Department is aware of contamination on a property, which is NOT part of a proposed remediation under a submitted NIR, the Department may suggest that the remediator include this area, or site, as part of the NIR. However, if the remediator declines to include other known areas of the property, the Department will NOT interfere with the voluntary cleanup and will approve a final report that otherwise meets the requirements of Act 2. The Department always reserves the right, as a separate action, to apply its enforcement discretion in requiring remediation of other contamination on the property which was not addressed by the voluntary cleanup in the NIR. However the exercise of such enforcement discretion is intended to be based on DEP=s knowledge of other contamination on the property, which may significantly threaten human health and/or the environment, not on a requirement that the property owner perform an environmental site assessment to identify other areas of concern. C. Improving Service through Program Consistency 3. DEP Central Office program collaboration on report disapprovals or withdrawal requests. In an effort to meet the expectations presented by statutory review timeframes, the Department requires that regional Environmental Cleanup Program managers must collaborate with the central program office prior to denying or honoring requests to withdraw submitted reports for required Act 2 submissions. 4. Dispute resolution team Persons who feel that DEP regional decisions on their site are not consistent with rules and policies may raise the regional decision to a Dispute Resolution Team. This team will meet on an as-needed basis and their decisions will e approved by Executive staff, binding on all involved parties, and provided within Act 2 timeframes. Disputes to be reviewed by the Dispute Resolution Team may be directed to Tom Fidler, Chief of the Land Recycling and Cleanup Program. (tfidler@state.pa.us) To minimize delays, field staff will provide a completeness review within two weeks on all submitted documents. 6. Brownfield action teams The Land Recycling Program will offer optional technical assistance on site characterization

2 and cleanup plan development through the establishment of brownfield action teams. These teams will be put together on an as-needed basis and will include a mix of field office and central office staff. Their goal will be to provide consistent and time-critical decisions and advice on projects where such help is warranted. If you would like your site to be considered for such a team, contact Tom Fidler, Chief of the Land Recycling and Cleanup Program. (tfidler@state.pa.us) 7. FAQ posted on website The Land Recycling Program website will include Frequently Asked Questions and a process whereby persons can submit questions via the web. F. Applying Land Recycling to Your Property 1. Classifying your Site and Considering Options for Remediation A distinct area of contamination includes the volume of all media affected by the release causing the contamination. For example, if soils were contaminated and that contamination migrated to groundwater, both the contaminated soil and groundwater would be part of the distinct areas of contamination associated with the release. In some cases, the Department may agree that characterizing all contaminated media as a distinct area is not practical and may approve a site characterization limited to a single medium. The department will accept NIRs for properties on which a release of regulated substances can be documented, or for properties affected by off-property releases of regulated substances for which the remediator is not responsible. The liability protection afforded under Chapter 5 of Act 2 is for contamination identified in the approved final report. By example, the lower the censoring level chosen in the site characterization, the larger the area and more regulated substances would likely be included in the site. a) Background A person cleaning up a site to the background standard must document that the concentration of any regulated substances remaining are at a level not related to any release of regulated substances at the site. d) Combination of Standards A cleanup may be performed by using any combination of the three standards. The remediator may select any one or a combination of standards by regulated substance, by medium of concern, or by distinct area of contamination (see Section I.D.1). Combinations must satisfy the requirements of each standard used. For example, in using any combination of standards which includes the site-specific standard, the risk assessment should include only those regulated substances for which site-specific numeric standards are being developed, and for these substances, the cumulative risk requirements of Section 304 of Act 2 must be met. Attainment of these site-specific numeric standards must be demonstrated in the final report. In addition, all of the requirements of the site-specific standard, including the reporting requirements, apply. All of the regulated substances, media, or distinct areas of contamination meeting another standard (e.g., the Statewide health standard) must meet the requirements of that standard. Therefore, in addition to a combination of numerical standards there will be combinations of requirements for reporting, attainment test, and points of compliance.

3 e) Special Industrial Areas The special industrial area designation was created by Act 2 to provide special remediation requirements for a distinct set of sites which were used for industrial activity. These sites are properties where there is no financially viable responsible party, or where the property is located within an enterprise zone. Enterprise zones are designated by the department of Community and Economic development. The remediator and the reuser afforded these special requirements must demonstrate that he/she did not cause or contribute to releases of regulated substances at the property. In order to make use of the special industrial area designation, the remediator must enter into a consent order and agreement with the Department. 3. Regulated Storage Tank Release Sites Storage tank cleanups conducted pursuant to the Storage Tank and Spill Prevention Act (Act 32 of 1989, as amended) which meet one or more of the standards under Act 2 and are Act 2 cleanups. Section 904(c) of Act 2 preserved the corrective action process for the remediation of releases from storage tanks regulated by Act 32. Regulated storage tanks include a wide range of underground and aboveground tanks containing petroleum products and hazardous substances. The corrective action process applies to releases from regulated tanks for which remediation (anything beyond notification) was initiated on or after August 5, 1989, the effective date of Act 32. Persons who take corrective action under Act 32, and can demonstrate attainment of one or more of the standards under Act 2, will qualify for liability protection. Where Act 32 applies, persons cleaning up these releases are not subject to the notice, fee and department approval provisions contained in Act 2. Likewise, the mandatory Department review times and the Adeemed approved@ provisions of Act 2 are not available for cleanups involving these releases. Those persons who initiated cleanup prior to their tanks becoming deregulated by Act 16 of 1995 (which amended Act 32) should continue to implement the corrective action process, along with use of the Act 2 remediation standards, to receive liability protection. Where the tank is not governed by Act 32, adherence to the Act 2 administrative process and cleanup standards will b e required in order to receive liability protection. When releases of petroleum products occur at sites with both Act 2 and Act 32 storage tanks, the remediator may elect to address the tanks together, or to address them separately on a dual track of the Act 2 and Act 32 processes. If the person elects to address the tanks together, combined reports and notices that satisfy the requirements of each statue, as they apply to the particular tanks, may be submitted. Department reviews will also be conducted to satisfy the requirements of both statutes. 4. Short List of Petroleum Products Table IV-9 contains an abbreviated list of regulated substances for specified products (e.g. gasoline). This short list may be used under any standard as long as the following conditions are met: $ Use of the short list is limited to remediation resulting from releases of the listed

4 petroleum products that are uncontaminated from other sources. $ For soil media attainment, there must be no free liquids left in the soil based on visual inspection, and the soil should not create any odor nuisance. $ For groundwater media attainment, there must be no measurable free floating product (0.01 ft-[epa]) at the point of compliance, (usually the property line). Extent of Site Characterization/DEP Assistance A complete and accurate site characterization, including fate and transport analysis, and its documentation in the final report is very important as it is the basis for making remediation decisions and is used later in identifying the appropriate area for demonstrating attainment. Without a proper site characterization, attainment requirements cannot be met and the final report will be disapproved by the Department. DEP Regional Office staff are a valuable resource and want to assist as needed in evaluating your site characterization information. Although not required, working with the department in many cases can help to facilitate approval of the submitted reports. Always feel free to contact the Department=s Regional Environmental Cleanup Program staff when you have a question about the requirements of site characterization of a property for the Land Recycling Program. b) Scope of Characterization The Scope of the site characterization should be designed to help the person conducting the cleanup select an appropriate remedy that will meet the attainment requirements of the selected Act 2 standard. The requirements that a full site characterization must meet are described in the regulations at Section During this phase of the application of Act 2, the remediator should evaluate other applicable regulatory requirements (See Section III of this manual), since information required by other programs may best be collected during the site characterization phase.

5 i) Soils In soils, the characterization must be at least to a concentration sufficiently below the appropriate Statewide health standard to insure that all areas containing regulated substances at or above the Statewide health standard have been adequately characterized, and that is sufficient to support a fate and transport analysis which shows where the contamination is currently located and those areas to which it is moving. The remediator determines the concentration level for characterization below the minimal level stated above. The remediator must state what factors were used in determining the level used to define the site boundaries. ii) Groundwater If groundwater is impacted by a release based o knowledge of the site or as a result of soil sampling, a similar process as used for soils to determine the extent of the release into groundwater may be employed based on knowledge of the site, groundwater monitoring, and fate and transport analysis. A common mistake is to take a limited set of groundwater measurements from a single sampling event and conclude that since the concentrations are below the Statewide health standard that no further work is need to obtain Act 2 liability relief. This is not true. Proper characterization requires more than one round of sampling ( (e)). In addition, attainment sampling and demonstration are required even if characterization samples are below the Statewide health standard ( (a)). iii) Conceptual site model including soil and groundwater When complete, the site characterization should enable the development of a conceptual site model. The conceptual site model is a written and graphical representation of the site environmental system and the processes that control the transport and movement of regulated substances through the environmental media and how they interact. Depending on the size and complexity of the site, the investigation portion of the site characterization typically is an iterative process which expands and builds as the information is gathered. EPA guidance or American Society for Testing Materials (ASTM) guidance appropriate for the site may be used as a source for general guidance when conducting the site characterization investigation. The DEP Groundwater Monitoring Guidance Manual is also appropriate. The data objectives of the site characterization will differ somewhat depending on whether soil or groundwater is being investigated. A good site characterization where the soil is a medium of concern should be able to provide the following information derived from field investigations: The types of regulated substances that are present, their concentrations and the spatial variation in concentration of the regulated substances both horizontally and vertically. $ The physical characteristics of the soil in which the regulated substances are present and through which they may be moving. These include the soil type (texture), dry bulk density, permeability, organic carbon content, porosity, and possible moisture content. Documentation of these properties and any significant variability over the site may be very important later in developing a fate and transport analysis. Where groundwater is a medium of concern, the following information at a minimum should be provided by a good site characterization:

6 $ The direction of groundwater flow, $ The hydraulic gradient, $ The permeability of the aquifer material(s) through which the groundwater moves, $ The porosity of the aquifer, and $ The types of regulated substances present, their concentrations and the spatial variation in concentration of the regulated substances both horizontally and vertically. This information is not only necessary to describe and evaluate conditions at the site, but also is often vital to fate and transport analysis, especially when it requires a quantitative approach. Fate and transport analysis is part of site characterization as well as demonstration of attainment and is required under all three Act 2 standards. Failure to have a fate and transport analysis in any final report is reason for disapproval based on this deficiency. 8. Management of Separate Phase Liquid (SPL) under Act 32 (The Storage Tank and Spill Prevention Act of 1989) and Act 2 The presence of Separate Phase Liquids (SPL) at contaminated sites does affect the responsibility of the remediator and limit the standards under which he may remediate. When a pure liquid such as gasoline is released to the environment at a sufficiently high rate, accumulations of the liquid as a separate phase may occur within soil or bedrock. Depending on the density of the liquid relative to water, the liquid will migrate under gravity through the unsaturated soil and/or bedrock column and either float on the water table or sink through the water column and accumulate on impermeable surfaces lower in the aquifer. Substances that are less dense than water, like most petroleum products, tend to float on the water table and are call Light Non-Aqueous Phase Liquids or LNAPLS. Substances such as chlorinated solvents which sink through the groundwater column are called Dense Non-Aqueous Phase Liquids or DNAPLs. SPL is encountered primarily where concentrated sources of the regulated substance are released into the environment such as at leaking tank sites. The presence of SPL in soil, on or within the aquifer, on surface water, or in sediments, if not removed, is a serious long term management concern at sites undergoing remediation. SPL, if not removed, constitutes a continu9ing source of contamination, may result in explosive, toxic or irritating vapors, will greatly increase the time and cost for post closure care monitoring, and introduces complex fate and transport issues and uncertainties regarding the future impact and migration of contamination at a site. a) Interim Remedial Actions under Chapter 245, Subchapter D (relating to releases from storage tanks regulated by Act 32 of 1989) and Interim Response under Chapter 250

7 Section (a) (3) (ii) requires that SPL recovery resulting from releases from regulated storage tanks be initiated immediately upon its discovery. Section (b) (1) requires that SPL removal be conducted in a manner that prevents the spread of contamination into uncontaminated areas. These requirements apply to releases from regulated storage tanks where SPL is present regardless of whether the statewide health or site-specific standard is selected for remediation of the site. SPL should be recovered to the maximum extent practicable with the minimum objective of preventing its migration into uncontaminated parts of the site, and eliminating threats to human health, safety, and the environment. While Act 2 and Chapter 250 do not specifically mandate SPL recovery within the property, the Department encourages removal of SPL within the property to the maximum extent practicable for any reasons as an immediate or interim response under Act 2. Incases relying on natural attenuation, removal of SPL will simplify and shorten requirements for postremediation care monitoring, fate and transport analyses will be simplified, and therefore, the time to attain a standard and eliminate postremediation care is likely to be greatly shortened at many sites. b) Maximum Extent Practicable Generally, for Act 2 remediations using the Statewide health standard, the Department urges removal of SPL throughout the plume to the maximum extent practicable. For sites being remediated under Chapter 245, the Department will require the removal of SPL throughout the SPL plume to the maximum extent practical. The Department recognizes that the amount of SPL that can be removed will depend on the hydrogeologic framework of the site, the type of product, the remediation technology employed and the effort put into it. Following EPA, the department has not quantified the term Amaximum extent practicable.@ For sites being remediated under Act 32, Remediations are referred to the publication EPA 510-R , AHow to Effectively Recover SPL at Leaking Underground Storage Tank Sites@. This publication provides general criteria for terminating recovery operations. The department will recognize these guidelines in determining compliance with the SPL removal requirements under Chapter 245. For sites being remediated under Act 2, the Department considers the extent of SPL removal to be a determination of the responsible party in accordance with the standard the remediator wishes to attain and demonstrate, after immediate threats to human health and safety and the environment have been mitigated by SPL removal as an interim remedial response. c) Relationship of Separate Phase Liquid to Compliance with Act 2 Standards i) Background standard The background standard is available at sites where SPL is migrating onto the property from an off-site source. Responsible parties will be required to demonstrate through the use of monitoring and fate and transport analysis that they have removed an amount of SPL equivalent to the mass contributed by the release from their site. ii) Statewide health standard Groundwater- The Department has determined by policy that the Statewide health standard is not available where SPL, as LNAPL or DNAPL, is present in property line compliance wells at sites being remediated under Act 2 or Act 32.

8 At sites where SPL remains within the interior of the property, remediators should document that presence in the deed to the property voluntarily (although not required by law under a residential Statewide health standard cleanup). This will provide notice to future landowners. Soil- In addition, within the property, the lesser of the direct contact number to a depth of fifteen feet for chemicals of concern and the soil-to-groundwater pathway number throughout the entire soil column must be attained in soil that is saturated with the SPL. This soil requirement applies to all sites including both those where the SPL has been removed and those where some amount remains. At sites where applicable soil standards have been attained, and the responsible person has determined that unrecoverable SPL remains, the responsible person will need to establish through monitoring and fate and transport modeling that any remaining SPL will not migrate to compliance points before a release of liability under the Statewide health standard will be conveyed. Where light phase SPL is present, monitoring will be required as part of the postremediation care program until the SPL has either dissipated or the Department concurs that monitoring and fate and transport analysis have established that any remaining SPL is stationary and diminishing. iii) Site-specific standard The site-specific standard is an important option when the remediator has determined that, for technical or economic reasons, attainment of either the Statewide health standard or the background standard is not feasible because of the presence of SPL. Attainment under the site-specific standard when SPL is present at the POC is permissible as long as there is no discharge to surface water and there is no unacceptable exposure (based on risk) to the contamination. 9. Notice Requirements and Procedures a) Notice of Intent to Remediate The NIR and instructions are available online at: In order to obtain sufficient site information to determine the scope of any site contamination and the remediation standard selection, some site characterization is recommended prior to submission of an NIR. Communication with the department staff in the region where the site is located to discuss procedures, assessment and remediation aspects is encouraged. Submission of site characterization reports with the NIR is encouraged. d) Remediation Report Notification Requirements i) Background and Statewide health standards Under the background and Statewide health standards, when a final report is submitted, the remediator should provide two copies of the final report to the Department s Environmental Cleanup Program regional office where the site is located. A complete submission consists of the report, A Transmittal Sheet, a printout of the online final report summary, the checklist and the appropriate fee.

9 Provide municipal and public notification. This notification is accomplished by: Sending a notice to the municipality that a final report has been submitted to the Department. Providing a notice of submission of the final report to a newspaper of general circulation in the area of the site. Providing the Department proof of the public and municipal notification by submitting a copy of the newspaper proof of publication document (or a photocopy of the published notification showing the publication date), and proof of municipal notification of submission of the final report by submitting a copy of the certified mail receipt card and cover letter of the municipal notice to the Department. ii) Site-specific standard Under the background and Statewide health standards, when a final report is submitted, the remediator should provide two copies of the final report to the Department s Environmental Cleanup Program regional office where the site is located. A complete submission consists of the report, A Transmittal Sheet, a printout of the online final report summary, the checklist and the appropriate fee(s). The remediator shall provide municipal and public notification of the submission. Sending a notice by certified mail to the municipality that a specific plan and/or report has been submitted to the Department. Providing a notice summarizing the findings and recommendations of the plan or report, along with the comments and responses, to a newspaper of general circulation in the area of the site. This notice shall be a legal notice or other appropriate format provided by the newspaper which will provide the required information. Providing the Department proof of the public and municipal notification by submitting a copy of the newspaper proof of publication document (or a photocopy of the published notification showing the publication date), and proof of municipal notification of submission of the final report by submitting a copy of the certified mail receipt card and cover letter of the municipal notice to the Department. Remedial investigation reports, cleanup plans, and risk assessment reports may be submitted together or separately. The Department has a 90-day review period. 3. Disposal after September 7, 1980, for Residual Waste and Construction/Demolition Waste, and between September 7, 1980 and October 9, 1993 for Municipal Waste. Municipal and residual waste disposal activities that occurred after September 7, 1980 are subject to Act 97, the terms and conditions of permits issued pursuant to Act 97 and to the municipal and residual waste regulations including an approved closure plan. Permitted facilities that are closed (prior to October 9, 1993 for municipal waste facilities) may use any one or a combination of the remediation standards for releases into soils or groundwater under Sections (g), (b) (4) or (c). In addition, the permitted facility may elect to proceed under Act 2 and upon approval of the final report obtain the liability protection afforded by Section 501 of Act 2 for the release. The cause of the release or spill must be

10 addressed in accordance with the terms and conditions of the closure plan or permit. Any relief of liability afforded under Act 2 relates only to the regulated substances identified and in no way is to superced the terms and conditions of the closure plan or permit. An unauthorized municipal waste landfill that ceased disposal prior to October 9, 1993 or an authorized construction/demolition waste landfill, residual waste landfill or an unauthorized disposal impoundment that ceased after September 7, 1980, where the Department has not required removal of the solid waste on the ground and use of Act 2 to remaining contaminated media, must be remediated in accordance with the following: removal of the non-media solids and use of any one or a combination of Act 2 standards of the remaining contaminated media, or closing in place by applying the applicable closure standards of the regulated facility encountered specified in Chapters 271, 273,287, 288 and 289 as required by Section 250.9(b) of the act 2 regulations (unless applicable operational standards are specifically waived by the department under the requirements of such waivers set forth at Sections (d), (b) and Section 902(b) of Act 2) and pathway elimination under the site-specific standard for the non-media solids on the ground and any one or a combination of Act 2 standards for soils and groundwater outside the perimeter of the closure area. In addition, the unauthorized facility can elect to proceed under Act 2 and upon approval of the find report obtain the liability protection afforded by Section 501 of Act 2 for the release. At properties where solid or liquid municipal or residual wastes such as metal, brick, block or debris were disposed, without permit, and became mixed with soil thereby becoming a part of the environmental media, the Act 2 program would govern remediation The remediator would choose the best applicable management practices to include covering, grading, revegetation, and related activities to prevent pollution, odors and other nuisances that would apply to the remediation of mixed media. Liability relief afforded by Act 2 would only apply to the area characterized and to the contaminants identified in the Act 2 final report. If the soil/waste mixture is moved offsite, the material must be managed as waste pursuant to Section of the Act 2 regulations and the definition of waste in the residual waste regulations. 4. Disposal of Hazardous Waste after September 7, 1980 or Municipal Waste after October 9, 1993 Subject to Federal Closure Requirements Hazardous Waste sites that have RCRA Subtitle C corrective action obligations may satisfy federal requirements by participating in the voluntary cleanup process provided by Act 2. For RCRA facilities with low or medium priority corrective action obligations, Act 2 standards may be applied as described below to satisfy both state and federal requirements concurrently. For high priority RCRA corrective action facilities, application of Act 2 standards as described below may also be used, but with greater interaction with EPA. a) Hazardous waste If hazardous waste was disposed before September 7, 1980 and continued after September 7, 1980 but before September 26, 1982 [see 40CFR 270.1(c) incorporated by reference in Section 270a.1] without interim status and the Department has not required removal of the hazardous waste and use of Act 2 to remaining contaminated media, the remediator must close the existing facility under closure standards provided in Chapter 265a of the hazardous waste

11 regulations for the facility unit encountered and upon approval of the final report by the Department obtain the liability protection afforded by Section 501(a) of Act 2. As examples, typical units encountered are surface impoundments and waste piles. Closure requirements set forth in 40 CFR (surface impoundment closure) and 40 CFR (waste pile closure), incorporated by reference in Chapter 265a, require removal of the solids and contaminated subsoils. To attain clean closure, the remediator should remove solids and contaminated subsoils that are above the level of the listing: i.e., characteristically hazardous solids and soils, and solids and soils contaminated by KPUF waste disposal above the residential Statewide health standard for used aquifers. Any soil or groundwater contamination remaining after clean closure must be remediated using any one or a combinations of Act 2 standards. If clean closure is not attained, the remediator must close the hazardous waste regulated unit in place using the closure standards for landfills set forth in 40 CFR and use the site-specific standard for the in-place closed area. Any release into groundwater or soil outside the approved in-place closure area is subject to any one or a combination of Act 2 standards (except the Statewide health nonuse aquifer standard, which has not been approved by EPA but which may be derived through use of the site-specific standard). Hazardous waste facilities created after September 7, 1980 and hazardous waste facilities existing on September 7, 1980 which continued to receive waste after September 26, 1982 are subject to the closure, post-closure and corrective action requirement of 40 CFR Part 264, as incorporated by reference in Chapter 264a. As examples, a surface impoundment in this category is subject to the closure requirements of 40CFR and a waste pile in this category is subject to the closure requirements of 40 CFR If clean closure is not attained, the remediator must close the regulated hazardous waste unit in place, using the closure standards for landfills set forth in 40 CFR and use the site-specific pathway elimination standard for the in-place closed area. Any release into groundwater or soils outside the approved in-place closure areas is subject to one or a combination of Act 2 standards (except the Statewide health nonuse aquifer standard as explained above) at a point of compliance for groundwater set forth in 40CFR b) Municipal waste If a permitted municipal waste landfill received waste between October 9, 1993 and December 23, 2000, a release from the landfill of a regulated substance must be remediated in accordance with a closure plan approved prior to December 23, 2000 or remediation standards in the municipal waste regulations that are similar to the federal requirements under Subtitle D of RCRA. A release of a regulated substance from a municipal waste landfill permitted on or after December 23, 2000 must be remediated in accordance with the remediation standards in the municipal waste regulations that are similar to the Subtitle D requirement in Section (b) (2). At properties where the unauthorized disposal of municipal waste occurred after October 9, 1993, remediation shall consist of removal of the non-media solids and the use of any one or a combination of Act 2 standards for the remaining contaminated media. Where the Department determines that the removal of the waste, which was not authorized disposal, is impracticable or will cause unacceptable impacts to public health or the environment, the remediation shall consist of closing the facility in place by applying the applicable closure standards of the regulated facility encountered specified in Chapter 271 and 273 as required by Section 250.9(b) of the Act 2 regulations and by using pathway elimination

12 under the site-specific standard for the non-media solids on the ground, and any one or a combination of act 2 standards for soils and groundwater outside the perimeter of the closure area that is consistent with the applicable requirements for groundwater remediation standards and point of compliance set forth in Section (b). 3. Impacts to Surface Water from Diffuse Flow of Contaminated Groundwater Sections and of the Act 2 regulations provide for determining compliance with surface water quality standards from a diffuse surface of groundwater discharge. For some sites selecting the statewide health groundwater standard for used aquifers with a TDS of 2500 mkg/l TDS or the site-specific standard for groundwater, this will involve analyzing the impact of a diffuse flow of a dissolved groundwater plume into a stream incorporating the methods and models of the Office of Water Management. All discharges involved with a remediation must be in compliance with the provisions of Chapter 93 to demonstrate attainment of the statewide health and site-specific standards. a) Statewide health Standard in Aquifers with 2500mg/L TDS or less For 65 compounds that have Statewide health standards established in Chapter 250, simply demonstrating attainment of the residential or nonresidential Statewide health standard medium-specific concentration (MSC) for groundwater in used aquifers with total dissolved solids (TDS) less than or equal to 2500 mkg/l at the point of compliance, or at the groundwater/surface water interface when the plume discharges to surface water prior to or instead of passing through the property line POC, will satisfy the surface water criteria attainment demonstration. This is because either the MSC is equal to or below the lowest surface water quality criterion (LSWC) or the compound in question does not have any corresponding surface water criteria at this time. These 65 compounds are listed in Table IV.1. The Department has identified 89 compounds which require a more detailed analysis. These compounds are listed in Tables IV.2 and IV.3. These tables also provide data that may be useful in demonstrating attainment of surface water quality criteria such as the PQL, LSWC and where background surface water quality data may need to be incorporated in the analysis. Table IV-2 identifies 24 compounds where the Act 2 MSC is above both the PQL and the LSWC, but the LSWC is below the PQL. Surface water quality attainment will be deemed to be attained when the concentration of these compounds at the point of compliance and any groundwater/surface water interface, whether prior to or downgradient of the property line POC, is below the PQL in all compliance wells. 1 Guidance for Attainment Demonstration with Statistical Methods 1. Introduction The requirement to apply statistical methods to verify the cleanup of a site is emphasized in Act 2. Sections 302, 303 and 304 of Act 2 require that attainment of a standard be demonstrated by the collection and analysis of samples from affected media (such as surface water, soil, groundwater in aquifers at the point of compliance) through the application of statistical tests set forth in regulation. The Act also requires the department to recognize those methods of attainment demonstration generally recognized as appropriate for that particular remediation. Statistical methods are emphasized because there is a practical need to make decisions regarding whether a site meets a cleanup standard in spite of uncertainty. The uncertainty

13 arises because we are able to sample and analyze only a small portion of the soil and groundwater at a site, yet we have to make a decision regarding the entire site. The purpose of this section is to provide guidance for the use of statistics to demonstrate that a site has attained a cleanup standard under Act 2. It is intended to address certain key issues pertinent to the sampling and statistical analysis under Act 2 to provide references for proper statistical analysis and, if necessary, to provide examples of applying statistical procedures in detail. It is not intended to address every statistical issue. For statistical attainment issues not addressed directly in this manual or the Act 2 regulations, a person may consult the latest EPA documents for additional guidance. EPA guidance documents (EPA 1989b, 1992b, 1992c, 1996) are particularly helpful. They provide detailed statistical procedures for demonstration of attainment and data analysis, Three of these documents are available from the World Wide Web at EPA QA/G-9 (EPA 1996) is available from the World Wide Web at For groundwater characterization, persons should consult the current DEP guidance document Groundwater Monitoring Guidance Manual (Section V.F) which provides general information on groundwater monitoring and sampling issues, such as monitoring well construction, locations and depths of monitoring wells, and well abandonment procedures. The DEP Groundwater monitoring Guidance Manual provides a good summary of various statistical methods used for groundwater characterization. Other references cited in this document and standard texts may be used to perform the procedures to demonstrate attainment as appropriate. If necessary, professional services should be obtained. When we consider applying statistical methods to demonstrate the attainment of a risk-based cleanup standard, it is important to realize that three components may influence the overall stringency of this cleanup standard: The first component is the magnitude, level, or concentration that is deemed protective of human health and the environment. The development of risk-based cleanup standards is addressed in the Act 2 regulations and Department s risk assessment guidance s. The second component of the standard is the sampling that is done to evaluate whether a site is above or below the standard. The final component is how the resulting data are compared with the standard to decide whether the remedial action was successful ( a statistical analysis). Persons overseeing cleanup must look beyond the cleanup level and explore the sampling and statistical analysis that will allow evaluation of the site relative to the cleanup level. This guidance is intended to address statistical analysis and sampling components that may affect the stringency of cleanup standards. D. Postremediation Care 1. Introduction This section provides general guidelines on the methodology of Postremediation care and

14 the postremediation care plan. The plan shall be submitted as part of the final report and approved by the Department. The approved postremediation care plan will become a condition of attainment of the chosen standard(s) under Act 2. The plan shall identify the activities that will be conducted after closure and the frequency of those activities. 2. Institutional versus Engineering Controls An institutional control, by definition of Act 2, is a measure taken to limit or prohibit certain activities that may interfere with the integrity of a remedial action or result in exposure to regulated substances at a site. These include, but are not limited to, fencing or restrictions on the future use of the site. An engineering control, by definition of Act 2, is a remedial action directed exclusively toward containing or controlling the migration of regulated substances through the environment. These include, but are not limited to, slurry walls, liner systems, caps, leachate collection systems and groundwater recovery trenches Example: A deed restriction prohibiting use of the property in some way is an institutional control. An impermeable cap that prevents volatilization to the atmosphere, controls contaminant migration by run- on and run- off, and limits dermal contact (hydraulic conductivity less than 1 x 107 cm/sec) is an engineering control. Institutional controls cannot be used to attain the background or Statewide health standards. Institutional controls alone cannot be used to attain the site- specific standard. Engineering and/ or institutional controls may be used to maintain all three standards. 3. Postremediation Care Plan The postremediation care plan should include the following: The reason(s) that the postremediation care plan is necessary (See Sections (g), , , !(d), and ). A schedule of operation and maintenance of the controls. Include a description of the planned maintenance activities and frequencies at which they will be performed and future plans for submission of proposed changes.. Information regarding the submission of quarterly monitoring results and analysis, or as otherwise approved by the Department, that demonstrates the effectiveness of the remedy. Include a description of the planned monitoring activities and frequencies at which they will be performed. The proposed method for reporting any instances of nonattainment of the selected standard{s). The proposed measures to be taken to correct nonattainment conditions as they occur. Include a description of the corrective measures that may be required for all possible nonattainment scenarios.

15 Information regarding the maintenance of records at the property where the remediation is being conducted for monitoring, sampling and analysis. Include the name, address and telephone number of the person or office to contact about the site during the postremediation care period. This person or office shall keep an updated postremediation plan during the postremediation care period. Documentation of a plan to maintain the mitigated ecological resource, report of success or failure of the mitigation measure, and demonstration of sustaining the measures up to five years from final report approval. If requested by the Department, documentation of financial ability to implement the remedy and the postremediation care plan. 4. Postremediation Monitoring In some situations, postremediation monitoring may be required as part of the postremediation care program. a) Duration In most cases, postremediation monitoring requirements will be developed on a case- by- case basis. The factors determining the duration of postremediation monitoring are the factors that determine whether a postremediation cafe plan is necessary. b) Frequency As stated in Section (g) of the regulations, postremediation monitoring will take place on a quarterly basis unless otherwise approved by the Department. The interval between sampling events should be short enough to allow for response and correction of any problems that may cause nonattainment at the point of compliance. Factors that could influence the need for an alternative postremediation monitoring schedule include site size, groundwater velocity, contaminant characteristics and the vulnerability of a site to pulses of contaminant migration during precipitation events. c) Cessation of Postremediation Monitoring Postremediation monitoring may be terminated when monitoring provisions set forth in the postremediation care plan are met, the engineering controls are no longer needed, and it can be documented by fate and transport analysis that the standard will not be exceeded in the future. 5. Postremediation Care Attainment A person may terminate postremediation care as approved in the final report if he can demonstrate attainment of the standard(s} without the engineering controls in

16 place, and document by a fate and transport analysis that the standard will not be exceeded in the future. An amendment to the postremediation care plan shall be submitted for approval by the Department. The postremediation care plan shall be amended whenever changes in operating plans or facility design, or events that occur during postremediation care, affect the currently approved postremediation care plan. Storage Tank Program Guidance 2. Corrective Action Process Checklist The flow chart in Figure IV- 9 shows the major steps and the decision- making process that responsible parties must follow if a release from a regulated storage tank is confirmed to have occurred. This process was designed to be as flexible as possible to accommodate the wide range of specific circumstances that characterize releases. The following are the major steps of the process: If a reportable release is confirmed. owners or operators must notify. by telephone. the DEP regional office responsible for the county in which the release occurred within 24 hours of confirming a release. In addition to basic facility and owner information. the notice must describe. to the extent information is available: the regulated substance involved; the quantity of the regulated substance involved; when and where the release occurred; the affected environmental media; impacts to water supplies. buildings. sewer or other utility lines; and interim remedial actions planned. initiated. or completed. Within 15 days of the telephone notice. the owner or operator must follow up with a written notification to the appropriate DEP regional office. DEP Central Office and any municipality impacted by the release. This written notice must include the same information as provided in the telephone notification and also should include any new information obtained within the 15 days. The owner or operator must provide follow- up written notification to the Department and any impacted municipality regarding new impacts to environmental media or water supplies. buildings or sewer or other utility lines. not previously reported. within 15 days of their discovery.

17 The Department has prepared a form, "Notification of Reportable Release/ Notification of Contamination," which can be used to satisfy the written notification requirements. In situations where the release is small, contained and immediately cleaned up, this form may be all that is necessary to complete the corrective action process. Also. upon confirmation of a release, responsible parties must immediately initiate interim remedial actions. These are required response actions from the time a release is confirmed until the time a formal long- term remedial action plan is implemented. Interim remedial actions help maintain or restore public health and safety and prevent the additional release of a regulated substance to the environment. Interim remedial acti9ns may be all that are necessary to adequately address certain releases. These releases may involve spills and overfills, and cases where a release is confined to the excavation zone of an underground tank. While all appropriate interim remedial actions must be taken in order to bring a release under control, the first priority at any release site is to identify and eliminate any threat to the health and safely of onsite personnel or nearby residents. See section for requirements for interim remedial actions. These interim actions can include: checking for and venting product vapors from sewer lines or buildings, that have been impacted; calling emergency personnel such as local fire and public safety officials for assistance where fire, explosion or safety hazards exist; relocating residents until potentially explosive vapors have been reduced to safe levels; restricting access to the site by nonessential personnel and establishing a buffer area around the site; recovering free product leaking into subsurface structures such as basements and sewers. Either concurrently with these emergency actions or as soon as any immediate, threats to human health and safety have been eliminated or reduced to acceptable levels, attention should be turned to preventing any further release of the regulated substance to the environment. Depending on the circumstances of the release, this may involve: arranging for and conducting the necessary tests to identify and confirm all sources of the release; removing product from the storage tanks; removing the storage tanks; excavating product- saturated soils;