Alternative Endpoints - Revision history

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Jhurley at 20:27, 21 August 2018

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Jhurley: /* Technical Impracticability (TI) Waivers */

2018-08-21T20:23:27Z

‎Technical Impracticability (TI) Waivers

Jhurley at 17:09, 26 July 2018

2018-07-26T17:09:43Z

Jhurley at 15:55, 26 July 2018

2018-07-26T15:55:57Z

Jhurley at 15:39, 26 July 2018

2018-07-26T15:39:03Z

Jhurley at 15:20, 18 July 2018

2018-07-18T15:20:13Z

Jhurley at 14:56, 18 July 2018

2018-07-18T14:56:01Z

Jhurley at 14:30, 18 July 2018

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 A TI waiver may be considered during any stage of the remedial process.  TI decisions have been made prior to or after full-scale remediation systems were implemented.  In the former case, the decisions were supported by detailed site characterization data and analysis, and Feasibility study (FS) evaluations of potential remedial technologies and their inability to overcome critical limitations to groundwater restoration.  In the latter case, data from the remediation system performance were used to evaluate technical impracticability along with information gained through remedy optimization and the evaluation of other potential remediation technologies. The primary guidance document on TI waivers was issued by the USEPA in 1993.<ref name= "USEPA_1993">U.S. Environmental Protection Agency (USEPA), 1993. Guidance for Evaluating the Technical Impracticability of Groundwater Restoration. Office of Solid Waste and Emergency Response, EPA/540-R, pp.93-080.[[media:USEPA-1993._Guidance_for_Evaluating_the_Technical_Impracticability_of_GW_Restoration.pdf | Report.pdf]]</ref> Table 1 summarizes the key USEPA publications related to TI waivers.
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 ==References==
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 ==Introduction==
-[[File:Hawley1w2 Fig1.png|500 px|thumbnail |right|Figure 1. TI Zone and other Remedy Components at the Koppers Oroville Wood Treatment Facility<ref>U.S. Environmental Protection Agency (USEPA), 2013. Fourth Five-Year Review for Koppers Company, Inc. Superfund Site, Oroville, Butte County, California. August.[[media:USEPA-2013_Koppers_Oroville_4th_5YR_.pdf| Report.pdf]]</ref>]] Alternative endpoints and other approaches were first described in an ESTCP report titled “Assessing alternative endpoints for groundwater remediation at contaminated sites”<ref name = "Deeb2011"/> and subsequently reiterated elsewhere<ref>Hawley, E.L., Deeb, R.A. and Levine, H., 2014. Groundwater Remediation and the Use of Alternative Endpoints at Highly Complex Sites. In Chlorinated Solvent Source Zone Remediation (pp. 627-652). Springer, New York, NY.[https://www.springer.com/us/book/9781461469216 doi: 10.1007/978-1-4614-6922-3]</ref>. Several types of alternative endpoints include the following: TI waivers, other [https://www.epa.gov/superfund/applicable-or-relevant-and-appropriate-requirements-arars Applicable Relevant and Appropriate Requirements (ARAR)] waivers, ACLs, state designations for technical impracticability, groundwater management/containment zones, and groundwater classification exception areas. Other organizations have since recognized the topic and discussed aspects of alternative endpoints in technical and regulatory guidance documents.<ref name= "ITRC2012">Interstate Technology & Regulatory Council (ITRC). 2012. Using Remediation Risk Management to Address Groundwater Cleanup Challenges at Complex Sites. RRM-2. Washington, D.C.: Interstate Technology & Regulatory Council, Remediation Risk Management Team.[[media:ITRC-2012._Using_Reediation_Risk_Management_to_addr_GW_Cleanup_Challenges.pdf| Report.pdf]]</ref><ref>USEPA, 2014. Groundwater Remedy Completion Strategy: Moving Forward with the End in Mind.[[media:USEPA-2014._Groundwater_Remedy_Completion_Strategy.pdf| Report.pdf]]</ref><ref name= "USEPA2011">U.S. Environmental Protection Agency (USEPA), 2011. Groundwater Road Map: Recommended Process for Restoring Contaminated Groundwater at Superfund Sites.[[media:USEPA-2011._Groundwater_Road_Map_-_Recommended_Process_for_Restoring_Cont._GW.pdf| Report.pdf]]</ref><ref>Kavanaugh, M.C., Arnold, W.A., Beck, B.D., Chin, Y., Chowdhury, Z., Ellis, D.E., Illangasekare, T.H., Johnson, P.C., Mehran, M., Mercer, J.W. and Pennell, K.D., 2013. Alternatives for managing the nation's complex contaminated groundwater sites. National Research Council, National Academies Press. [[media:NRC-2013_Alternatives_for_Managing_Complex_GW_Sites.pdf| doi 10.17226/14668 Report.pdf]]</ref><ref>National Research Council, 2005. Contaminants in the subsurface: Source zone assessment and remediation. National Academies Press.[[media:NRC-2005_Contaminants_in_the_Subsurface.pdf| doi 10.17226/11146 Report.pdf ]]</ref> The following sections examine several examples of alternative endpoints and other approaches, and also provide
+[[File:Hawley1w2 Fig1.png|500 px|thumbnail |right|Figure 1. TI Zone and other Remedy Components at the Koppers Oroville Wood Treatment Facility<ref>U.S. Environmental Protection Agency (USEPA), 2013. Fourth Five-Year Review for Koppers Company, Inc. Superfund Site, Oroville, Butte County, California. August.[[media:USEPA-2013_Koppers_Oroville_4th_5YR_.pdf| Report.pdf]]</ref>]] Alternative endpoints and other approaches were first described in an ESTCP report titled “Assessing alternative endpoints for groundwater remediation at contaminated sites”<ref name = "Deeb2011"/> and subsequently reiterated elsewhere<ref>Hawley, E.L., Deeb, R.A. and Levine, H., 2014. Groundwater Remediation and the Use of Alternative Endpoints at Highly Complex Sites. In Chlorinated Solvent Source Zone Remediation (pp. 627-652). Springer, New York, NY.[https://www.springer.com/us/book/9781461469216 doi: 10.1007/978-1-4614-6922-3]</ref>. Several types of alternative endpoints include the following: TI waivers, other [https://www.epa.gov/superfund/applicable-or-relevant-and-appropriate-requirements-arars Applicable Relevant and Appropriate Requirements (ARAR)] waivers, ACLs, state designations for technical impracticability, groundwater management/containment zones, and groundwater classification exception areas. Other organizations have since recognized the topic and discussed aspects of alternative endpoints in technical and regulatory guidance documents.<ref name= "ITRC2012">Interstate Technology & Regulatory Council (ITRC). 2012. Using Remediation Risk Management to Address Groundwater Cleanup Challenges at Complex Sites. RRM-2. Washington, D.C.: Interstate Technology & Regulatory Council, Remediation Risk Management Team.[[media:ITRC-2012._Using_Reediation_Risk_Management_to_addr_GW_Cleanup_Challenges.pdf| Report.pdf]]</ref><ref>USEPA, 2014. Groundwater Remedy Completion Strategy: Moving Forward with the End in Mind.[[media:USEPA-2014._Groundwater_Remedy_Completion_Strategy.pdf| Report.pdf]]</ref><ref name= "USEPA2011">U.S. Environmental Protection Agency (USEPA), 2011. Groundwater Road Map: Recommended Process for Restoring Contaminated Groundwater at Superfund Sites.[[media:USEPA-2011._Groundwater_Road_Map_-_Recommended_Process_for_Restoring_Cont._GW.pdf| Report.pdf]]</ref><ref>Kavanaugh, M.C., Arnold, W.A., Beck, B.D., Chin, Y., Chowdhury, Z., Ellis, D.E., Illangasekare, T.H., Johnson, P.C., Mehran, M., Mercer, J.W. and Pennell, K.D., 2013. Alternatives for managing the nation's complex contaminated groundwater sites. National Research Council, National Academies Press. [[media:NRC-2013_Alternatives_for_Managing_Complex_GW_Sites.pdf| doi 10.17226/14668 Report.pdf]]</ref><ref>National Research Council, 2005. Contaminants in the subsurface: Source zone assessment and remediation. National Academies Press.[[media:NRC-2005_Contaminants_in_the_Subsurface.pdf| doi 10.17226/11146 Report.pdf ]]</ref> The following sections examine several examples of alternative endpoints and other approaches, and also provide references for more information.
 ==Technical Impracticability (TI) Waivers==

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 ==Technical Impracticability (TI) Waivers==
-Remediation goals in the [https://www.epa.gov/superfund/superfund-cercla-overview Comprehensive Environmental Response Compensation and Liability Act (CERCLA)] program, also known as the Superfund program, are based on ARARs.  An ARAR may be waived due to “technical impracticability” if technical/engineering challenges preclude the complete restoration of contaminated groundwater within a reasonable time frame [https://www.law.cornell.edu/cfr/text/40/300.430 (40 CFR 300.430(f)(1)(ii)(C))]. For example, a drinking water [[wikipedia:Maximum Contaminant Level | Maximum Contaminant Level (MCL)]] may be waived for a particular groundwater contaminant due to the technical inability to reach the MCL within a reasonable timeframe at a given area of the site. The [[wikipedia:Record of Decision | Record of Decision (ROD)]] or other final remedy decision document would cite the applicability of a TI waiver based on a detailed site-specific TI evaluation report and would specify the area of the aquifer within which the TI waiver applies (“TI zone”) as well as the lithologic unit or depth interval where the TI waiver applied. The ROD would also specify the remedial approach to meet ARARs outside of the TI zone and would describe how the TI zone would be protected (e.g., deed restrictions, groundwater use restrictions, slurry wall). As of 2012, TI waivers had been used at 85 CERCLA sites.<ref name= "USEPA2012">U.S. Environmental Protection Agency (USEPA), 2012. Summary of Technical Impracticability Waivers at National Priorities List Sites. Report with General Technical Impracticability Site Information Sheets. OSWER Directive 9230.2-24.[[media:USEPA-2012._Summary_of_Technical_Impracticability_Waivers.pdf| Report.pdf]]</ref>
+Remediation goals in the [https://www.epa.gov/superfund/superfund-cercla-overview Comprehensive Environmental Response Compensation and Liability Act (CERCLA)] program, also known as the Superfund program, are based on ARARs.  An ARAR may be waived due to “technical impracticability” if technical/engineering challenges preclude the complete restoration of contaminated groundwater within a reasonable time frame [https://www.law.cornell.edu/cfr/text/40/300.430 (40 CFR 300.430(f)(1)(ii)(C))]. For example, a drinking water [[wikipedia:Maximum Contaminant Level | Maximum Contaminant Level (MCL)]] may be waived for a particular groundwater contaminant due to the technical inability to reach the MCL within a reasonable timeframe at a given area of the site. The [[wikipedia:Record of Decision | Record of Decision (ROD)]] or other final remedy decision document would cite the applicability of a TI waiver based on a detailed site-specific TI evaluation report and would specify the area of the aquifer within which the TI waiver applies (“TI zone,” for example see Figure 1) as well as the lithologic unit or depth interval where the TI waiver applied. The ROD would also specify the remedial approach to meet ARARs outside of the TI zone and would describe how the TI zone would be protected (e.g., deed restrictions, groundwater use restrictions, slurry wall). As of 2012, TI waivers had been used at 85 CERCLA sites.<ref name= "USEPA2012">U.S. Environmental Protection Agency (USEPA), 2012. Summary of Technical Impracticability Waivers at National Priorities List Sites. Report with General Technical Impracticability Site Information Sheets. OSWER Directive 9230.2-24.[[media:USEPA-2012._Summary_of_Technical_Impracticability_Waivers.pdf| Report.pdf]]</ref>
-A TI waiver may be considered during any stage of the remedial process.  TI decisions have been made prior to or after full-scale remediation systems were implemented.  In the former case, the decisions were supported by detailed site characterization data and analysis, and Feasibility study (FS) evaluations of potential remedial technologies and their inability to overcome critical limitations to groundwater restoration.  In the latter case, data from the remediation system performance were used to evaluate technical impracticability along with information gained through remedy optimization and the evaluation of other potential remediation technologies.
+A TI waiver may be considered during any stage of the remedial process.  TI decisions have been made prior to or after full-scale remediation systems were implemented.  In the former case, the decisions were supported by detailed site characterization data and analysis, and Feasibility study (FS) evaluations of potential remedial technologies and their inability to overcome critical limitations to groundwater restoration.  In the latter case, data from the remediation system performance were used to evaluate technical impracticability along with information gained through remedy optimization and the evaluation of other potential remediation technologies. The primary guidance document on TI waivers was issued by the USEPA in 1993.<ref name= "USEPA_1993">U.S. Environmental Protection Agency (USEPA), 1993. Guidance for Evaluating the Technical Impracticability of Groundwater Restoration. Office of Solid Waste and Emergency Response, EPA/540-R, pp.93-080.[[media:USEPA-1993._Guidance_for_Evaluating_the_Technical_Impracticability_of_GW_Restoration.pdf | Report.pdf]]</ref> Table 1 summarizes the key USEPA publications related to TI waivers.
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 The primary guidance document on TI waivers was issued by the USEPA in 1993.<ref name= "USEPA_1993">U.S. Environmental Protection Agency (USEPA), 1993. Guidance for Evaluating the Technical Impracticability of Groundwater Restoration. Office of Solid Waste and Emergency Response, EPA/540-R, pp.93-080.[[media:USEPA-1993._Guidance_for_Evaluating_the_Technical_Impracticability_of_GW_Restoration.pdf| Report.pdf]]</ref> Table 1 summarizes the key USEPA publications related to TI waivers.
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 ==References==
 <references />

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-'''Table 1. Summary of Key USEPA Documents Pertaining to TI Waivers'''
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 '''Table 1. Summary of Key USEPA Documents Pertaining to TI Waivers'''
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 !style="background-color:#CEE0F2;" | DATE!!style="background-color:#CEE0F2;"| USEPA DOCUMENT!!style="background-color:#CEE0F2;"| DESCRIPTION
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 | 2016 || Clarification of the Consultation Process for Evaluating the Technical Impracticability of Groundwater Restoration at CERCLA Sites. OLEM Directive 9200.3-117<ref>U.S. Environmental Protection Agency (USEPA), 2016. Clarification of the Consultation Process for Evaluating the Technical Impracticability of Groundwater Restoration at CERCLA Sites. OLEM Directive 9200.3-117.[[media:USEPA-2016._Clarification_of_the_Consultation_Process_for_Eval._Tech._Imprac._of_GW_Rest..pdf| Report.pdf]]</ref> || The memo provides clarification of existing relevant Superfund policy and guidance and recommendations for planning and developing TI evaluation packages and describes the recommended process for EPA internal review and approval. The memo transmits five new recommended products, including a consultation process flowchart, TI evaluation flowchart, regional TI evaluation work planning spreadsheet, EPA review routing slip, and a summary checklist for the TI evaluation.
-|}.
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 ==Greater Risk and Other Applicable or Relevant and Appropriate Requirements (ARAR) Waivers==

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 ==Alternate Concentration Limits (ACLs)==
-The term ACL refers to an alternate concentration limit that site stakeholders agree upon as the cleanup level to replace a chemical-specific ARAR (at CERCLA sites) or risk-based criteria (at sites in the [[wikipedia: Resource Conservation and Recovery Act | Resource Conservation and Recovery Act(RCRA)]] program). At CERCLA sites, ACLs can only be considered if site conditions meet the following three criteria [http://legcounsel.house.gov/Comps/CERCLA.pdf (CERCLA Section 121(d)(2)(B)(ii))]:
+The term ACL refers to an alternate concentration limit that site stakeholders agree upon as the cleanup level to replace a chemical-specific ARAR (at CERCLA sites) or risk-based criteria (at sites in the [[wikipedia: Resource Conservation and Recovery Act | Resource Conservation and Recovery Act(RCRA)]] program). At CERCLA sites, ACLs can only be considered if site conditions meet the following three criteria [[Media:CERCLA.pdf | (CERCLA Section 121(d)(2)(B)(ii))]]:
 #Groundwater discharges to surface water (through known or projected points of entry)
 #Groundwater discharge does not lead to a “statistically significant increase” in contaminants in surface water or any “accumulation” of contaminants downstream
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 In addition to meeting these three criteria, a 2005 US EPA policy memorandum includes a list of other factors that must be considered before establishing an ACL at a CERCLA site<ref name= "USEPA2005">U.S. Environmental Protection Agency (USEPA), 2005. Use of Alternate Concentration Limits in Superfund cleanups. OSWER 9200.4-39.[[media:USEPA-2005._Use_of_Alternate_Concentation_Limits_in_Superfund_Cleanups_Memorandum.pdf| Report.pdf]]</ref>.  Site regulators must consider whether all groundwater plumes are discharging to surface water and the potential accumulation or effect of degradation byproducts in groundwater or surface water<ref name= "USEPA2005"/>. ACLs were rescinded at one site based on the USEPA memorandum and a TI waiver was issued instead<ref name = "Deeb2011"/>.
-At RCRA sites, the term ACLs has a different meaning and is less prescriptive. ACLs can be used at RCRA sites if the alternate concentration does not pose a substantial risk to human health or environment [https://www.law.cornell.edu/cfr/text/40/264.94 (40 CFR 264.94)]. A determination is made after considering potential adverse effects on the quality of groundwater and hydraulically-connected surface water. Several factors to consider include the waste characteristics and mobility, hydrogeologic setting, groundwater flow, groundwater and surface water usage (current and future), surface water quality standards, existing groundwater and surface water quality and quantity, rainfall patterns, proximity of source zone to surface waters, potential for human exposure and related health risks, potential for other risks, and the permanence of potential adverse effects [https://www.law.cornell.edu/cfr/text/40/264.94 (40 CFR 264.94)].
+At RCRA sites, the term ACLs has a different meaning and is less prescriptive. ACLs can be used at RCRA sites if the alternate concentration does not pose a substantial risk to human health or environment [https://www.law.cornell.edu/cfr/text/40/264.94 (40 CFR 264.94(b))]. A determination is made after considering potential adverse effects on the quality of groundwater and hydraulically-connected surface water. Several factors to consider include the waste characteristics and mobility, hydrogeologic setting, groundwater flow, groundwater and surface water usage (current and future), surface water quality standards, existing groundwater and surface water quality and quantity, rainfall patterns, proximity of source zone to surface waters, potential for human exposure and related health risks, potential for other risks, and the permanence of potential adverse effects [https://www.law.cornell.edu/cfr/text/40/264.94 (40 CFR 264.94(b))].
 Several RCRA sites have used surface water quality criteria in conjunction with dilution calculations, mixing zone modeling, and/or fate and transport modeling to determine the numerical value of the ACL for groundwater. Other groundwater ACLs have been determined based on site-specific risk assessments<ref name = "Deeb2011"/>.
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 == State Approaches ==
 [[File:Hawley1w2 Table2 R.PNG|thumbnail|600 px|right| Adapted from ITRC 2012<ref name= "ITRC2012"/>]]
-State remediation programs have developed a variety of designations that can be used to establish zones where contaminated groundwater can be managed or within which alternative cleanup standards can be adopted. Each designation and its primary purpose varies from state to state; most states have a system for classifying groundwater aquifer use, value and vulnerability. Groundwater re-classification can therefore change remedial goals. Some states permit groundwater classification exceptions or site-specific groundwater classification.  Others have designations similar to the CERCLA TI waiver where a TI zone can be established and managed to contain and monitor residual contamination. Finally, some state designations are primarily intended to track institutional controls and monitor/ track areas of groundwater contamination above permissible levels and their related institutional controls. These concepts are also consistent with the ability to designate alternative points of compliance as a way of monitoring protectiveness and managing residual contamination as remediation slowly proceeds. Table 2 lists examples of state-specific designations for groundwater.
+State remediation programs have developed a variety of designations that can be used to establish zones where contaminated groundwater can be managed or within which alternative cleanup standards can be adopted. Each designation and its primary purpose varies from state to state; most states have a system for classifying groundwater aquifer use, value and vulnerability. Groundwater re-classification can therefore change remedial goals. Some states permit groundwater classification exceptions or site-specific groundwater classification.  Others have designations similar to the CERCLA TI waiver where a TI zone can be established and managed to contain and monitor residual contamination. Finally, some state designations are primarily intended to monitor areas of groundwater contamination above permissible levels and track their related institutional controls. These concepts are also consistent with the ability to designate alternative points of compliance as a way of monitoring protectiveness and managing residual contamination as remediation slowly proceeds. Table 2 lists examples of state-specific designations for groundwater.
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 ==Greater Risk and Other Applicable or Relevant and Appropriate Requirements (ARAR) Waivers==
-As stated in [https://www.law.cornell.edu/cfr/text/40/300.430#f_1_ii_C CERCLA Section 121(d)(4)], a greater risk ARAR waiver is appropriate if compliance with the requirement would result in greater risk to human health and environment compared with non-compliance.
+As stated in [https://www.law.cornell.edu/cfr/text/40/300.430 CERCLA Section 121(d)(4) and in 40 CFR 300.430(f)(1)(ii)(C)], a greater risk ARAR waiver is appropriate if compliance with the requirement would result in greater risk to human health and environment compared with non-compliance.
 Several ARARs have been waived because meeting them would entail the use of remedial actions that pose a greater risk to human health and the environment. Examples of scenarios that could constitute greater risk include the following:
 *Mobilization of contaminants during remedial activity, causing greater risk to deeper or nearby drinking water aquifers

← Older revision		Revision as of 14:30, 18 July 2018
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	A TI waiver may be considered during any stage of the remedial process. TI decisions have been made prior to or after full-scale remediation systems were implemented. In the former case, the decisions were supported by detailed site characterization data and analysis, and Feasibility study (FS) evaluations of potential remedial technologies and their inability to overcome critical limitations to groundwater restoration. In the latter case, data from the remediation system performance were used to evaluate technical impracticability along with information gained through remedy optimization and the evaluation of other potential remediation technologies.		A TI waiver may be considered during any stage of the remedial process. TI decisions have been made prior to or after full-scale remediation systems were implemented. In the former case, the decisions were supported by detailed site characterization data and analysis, and Feasibility study (FS) evaluations of potential remedial technologies and their inability to overcome critical limitations to groundwater restoration. In the latter case, data from the remediation system performance were used to evaluate technical impracticability along with information gained through remedy optimization and the evaluation of other potential remediation technologies.
−	The primary guidance document on TI waivers was issued by the USEPA in 1993<ref name= "USEPA_1993">U.S. Environmental Protection Agency (USEPA), 1993. Guidance for Evaluating the Technical Impracticability of Groundwater Restoration. Office of Solid Waste and Emergency Response, EPA/540-R, pp.93-080.[[media:USEPA-1993._Guidance_for_Evaluating_the_Technical_Impracticability_of_GW_Restoration.pdf\| Report.pdf]]</ref>; Table 1 summarizes the key USEPA publications related to TI waivers.	+	The primary guidance document on TI waivers was issued by the USEPA in 1993.<ref name= "USEPA_1993">U.S. Environmental Protection Agency (USEPA), 1993. Guidance for Evaluating the Technical Impracticability of Groundwater Restoration. Office of Solid Waste and Emergency Response, EPA/540-R, pp.93-080.[[media:USEPA-1993._Guidance_for_Evaluating_the_Technical_Impracticability_of_GW_Restoration.pdf\| Report.pdf]]</ref> Table 1 summarizes the key USEPA publications related to TI waivers.