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TCEQ National Comments Log - Comments Relating to Waste Issues

Official statements of the TCEQ's position regarding national policies and activities relating to waste issues.

See also: 2003-2009: TCEQ National Comments Relating to Waste Issues

 

2010 to Current: TCEQ National Comments Relating to Waste Issues
Date
Submitted
Short Title
08/15/16 U.S. Nuclear Regulatory Commission's (NCR) Concentration Averaging and Encapsulation Branch Technical Position
04/14/16 Addition of a Subsurface Intrusion Component to the Hazard Ranking System
12/21/15 Management Standards of Hazardous Waste Pharmaceuticals
12/21/15 EPA Proposed Hazardous Waste Generator Improvements Rule
07/20/15 Nuclear Regulatory Commission (NRC): Low-level Radioactive Waste Disposal
05/12/15 Health and Environmental Protection Standards for Uranium and Thorium Mill Tailings
07/16/14 Nuclear Regulatory Commission (NRC): Strategic assessment update
09/03/13 Identification and Listing of Special Wastes; Disposal of Coal Combustion Residuals (CCRs) From Electric Utilities
05/06/13 Revisions to 10 CFR Part 61
01/07/13 Proposed revisions to 10 CFR Part 61, Licensing Requirements for Land Disposal of Radioactive Waste
02/21/12 Non-Hazardous Secondary Materials That Are Solid Waste
10/20/11 Rulemaking on the Definition of Solid Waste
09/30/11 Municipal Solid Waste (MSW), Recycling, and Source Reduction Measurement in the U.S.
05/27/11 2011 Hazardous Waste Report: Notification of Regulated Waste Activity, and Part A Hazardous Waste Permit Application and Modification
11/19/10 Hazardous and Solid Waste Management System; Disposal of Coal Combustion Residuals From Electric Utilities
08/03/10 Identification of Non-Hazardous Secondary Materials That Are Solid Waste
02/26/10 Draft Recommended Interim Preliminary Remediation Goals for Dioxin in Soil at CERCLA and RCRA Sites

DATE SUBMITTED: 08/15/16

SHORT TITLE: US Nuclear Regulatory Commission's (NCR) Concentration Averaging and Encapsulation Branch Technical Position Adobe Acrobat PDF Document

SUBMITTED TO: U.S. Nuclear Regulatory Commission

OFFICE PREPARING: Office of Waste

STAFF CONTACT: Bobby Janecka

SUMMARY OF CONTENTS

The TCEQ supports further clarification between contaminated materials and contaminated trash be provided by the NRC. The NRC may consider revising the term contaminated trash or the CA BTP, if their intention is to refer to compactible and non-compactible trash, in order to be consistent. The TCEQ does not consider it necessary for the NRC to develop additional numerical constraints for distinguishing between materials and trash, as the current numerical constraints in the revised CA BTP encompass almost all scenarios for classification based on waste types.

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DATE SUBMITTED: 04/14/16

SHORT TITLE: Addition of a Subsurface Intrusion Component to the Hazard Ranking System Adobe Acrobat PDF Document

SUBMITTED TO: U.S. Environmental Protection Agency

OFFICE PREPARING: Office of Waste

STAFF CONTACT: Brent Wade

SUMMARY OF COMMENTS: Comments Microsoft Word Document

  • The TCEQ recommends that EPA consider postponing finalizing the rule until the proposed additional guidance on implementation is prepared to allow states the ability to provide meaningful comment on the proposed rule;
  • The TCEQ seeks clarification on EPA’s intent for funding the continued maintenance of any mitigation systems installed as interim protective measures;
  • There are potential resource implications to states given the limited of number of site assessments that EPA would conduct;
  • The proposed rule appears to include discrepancies between the SsI component and existing exposure pathways of the HRS with regard to how observed releases are used to evaluate areas of actual and potential contamination;
  • The proposed rule creates scenarios that could result in a high bias of populations subject to exposures to areas of potential contamination by the proposed inclusion of occupied structures where indoor air sampling has not documented an observed exposure to areas of subsurface contamination;
  • The TCEQ seeks clarification on whether air sampling of regularly occupied structures may be used to eliminate observed exposures;
  • The proposed rule may compel the expansion of data collection in exposure pathways not expected to contribute significantly to the site score in order to ascertain the boundaries of an area of subsurface contamination as part of the evaluation of the SsI component or to rule out the SsI component;
  • The level of effort required to score a site for the SsI component is greater than the typical level of effort required to score all of the other existing HRS components;
  • The TCEQ seeks clarification on when and how EPA intends to provide appropriate training to states that evaluate sites for placement on the NPL;
  • Considering the purpose of the HRS as a screening tool, EPA may want to consider an alternate carcinogenic risk level; and
  • There are several inconsistencies between the 2015 EPA vapor intrusion guidance document and the proposed rule.

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DATE SUBMITTED: 12/21/15

SHORT TITLE: Management Standards of Hazardous Waste Pharmaceuticals Adobe Acrobat PDF Document

SUBMITTED TO: U.S. Environmental Protection Agency

OFFICE PREPARING: Office of Waste

STAFF CONTACT: Bill Shafford

SUMMARY OF COMMENTS: Comments Microsoft Word Document

The rule as proposed may not reduce the regulatory burden on Healthcare Facilities (HCFs) as much as EPA intends. The HCFs would have two sets of standards to manage hazardous pharmaceutical wastes; creditable and non-creditable. Non-creditable hazardous waste appears to be subject to full regulation in Part 262. Additional clarification would be needed in a number of areas, including waste handling, waste tracking, disposal, and potential conflicts with U.S. Drug Enforcement Agency (DEA) requirements. Clarifications would be needed for both implementation and enforceability.

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DATE SUBMITTED: 12/21/15

SHORT TITLE: EPA Proposed Hazardous Waste Generator Improvements Rule Adobe Acrobat PDF Document

SUBMITTED TO: U.S. Environmental Protection Agency

OFFICE PREPARING: Office of Waste

STAFF CONTACT: Bill Shafford

SUMMARY OF COMMENTS: Comments Microsoft Word Document

The comments seek clarification on several issues, including some waste tracking and manifesting requirements for very small quantity generators, and facility identification and reporting requirements.

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DATE SUBMITTED: 07/20/15

SHORT TITLE: Nuclear Regulatory Commission (NRC): Low-level Radioactive Waste Disposal Adobe Acrobat PDF Document

SUBMITTED TO:Nuclear Regulatory Commission

OFFICE PREPARING: Office of Waste

STAFF CONTACT:Charles Maguire

SUMMARY OF COMMENTS: Comments Microsoft Word Document

  1. The TCEQ agrees with proposed changes for conducting technical analyses.
  2. The TCEQ agrees with development of site-specific waste acceptance criteria
  3. The TCEQ recommends the NRC modify the proposed compatibility categories to provide greater flexibility to those states so that Texas would not be required to lower the degree of protectiveness of its current standards.

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DATE SUBMITTED: 05/12/15

SHORT TITLE: Health and Environmental Protection Standards for Uranium and Thorium Mill Tailings Adobe Acrobat PDF Document

SUBMITTED TO: U.S. Environmental Protection Agency

OFFICE PREPARING: Office of Waste

STAFF CONTACT: Charles Maguire

SUMMARY OF COMMENTS:

EPA's proposed rules would have a unique effect on Texas because Texas has an active uranium industry; the TCEQ has successfully regulated the underground operations at in situ uranium mining operations under the UIC program for over 40 years; and TCEQ administers the Agreement State licensing program for uranium recovery under the Atomic Energy Act. Therefore, staff reviewed the proposal and accompanying documentation and recommend that TCEQ submit comments to EPA.

The developed comments offer two recommendations. The first part identifies numerous jurisdictional and technical problems with the proposed rules. This part recommends that EPA withdraw the proposed rules; study active and historic uranium mining sites; and re-propose rules, if necessary, under the UIC authority in the Safe Drinking Water Act.

Staff developed comments on the proposed rules that address EPA’s jurisdiction and authority under UMTRCA, the need for the proposed rules, and concerns with specific technical requirements. The comments addressing jurisdictional authority discuss EPA’s specific statutory charge to adopt technical requirements relating to the management and disposal of byproduct materials and point out that byproduct material is not generated in the subsurface ore bodies. The comments question why EPA did not propose the rules under its UIC program as the requirements are addressing underground injection activities rather than waste management activities. The comments address EPA’s need for the rules and question why EPA has decided to propose these rules without any cited instances of contamination of underground sources of drinking water from in situ uranium operations in Texas. TCEQ recommends that EPA conduct studies of on-going and closed uranium operations to investigate groundwater or contaminant movement before proposing new rules. Technical comments include questions and assumptions about EPA’s statistical techniques for establishing baseline water quality, excursion detection limits, and establishing groundwater stability. The comments point out flawed reasoning and assumptions regarding hydrogeology and geochemistry associated with uranium ore bodies and in situ mining techniques. The comments point out the inappropriate analogy of the mined uranium ore body to a failed hazardous waste management unit that is the basis for the 30 year post-restoration stability demonstration period. The comments also question how the Agreement State program can implement all of the requirements at facilities that have already started mining.

The second part of the comment document identifies three changes to the proposed rules that TCEQ considers essential for implementation if EPA decides not to withdraw the proposal. These changes request the new rules be applied only to new uranium mines licensed after January 1, 2019 and not be applied to existing mines; eliminate the 30-year long term stability monitoring period and rely on a 3-year stability monitoring period; and make the rules effective on January 1, 2019 to allow TCEQ sufficient time to implement them.

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DATE SUBMITTED: 07/16/14

SHORT TITLE: Nuclear Regulatory Commission (NRC): Strategic assessment update Adobe Acrobat PDF Document

SUBMITTED TO: U.S. Nuclear Regulatory Commission

OFFICE PREPARING: Office of Waste

STAFF CONTACT: Charles Maguire

SUMMARY OF COMMENTS:

  1. The TCEQ identifies seven issues of new or increased importance over the next 5-7 years regarding LLRW, which include long-term performance, effectiveness of engineered designs, greater than Class C waste, and security of sealed sources.
  2. The TCEQ recommends certain revisions to the NRC Task and Priority List including increasing the priority of providing regulatory guidance for greater than Class C waste, removing the priority of considering scenarios of severe curtailment of disposal capacity, and including the new priority of reevaluating the National Source Tracking System.
  3. The TCEQ recommends that the NRC strongly consider providing states maximum flexibility within the context of compatibility requirements of potential future rulemaking and that consideration should be given to the potential impacts to operating existing disposal sites from any future changes in the regulatory framework.
  4. The TCEQ recommends that the NRC update their potential alternative future scenarios to reflect current disposal options, which now includes the operational LLRW disposal site in Texas.

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DATE SUBMITTED: 09/03/13

SHORT TITLE: Identification and Listing of Special Wastes; Disposal of Coal Combustion Residuals (CCRs) From Electric Utilities Adobe Acrobat PDF Document

SUBMITTED TO: U.S. Environmental Protection Agency

OFFICE PREPARING: Office of Waste

STAFF CONTACT: Tanveer Anjum

SUMMARY OF COMMENTS:

The time frames proposed by EPA for initiating and completing closure of CCR management units are impractical. The Waste Permits Division recommends the following:

Time Frame to Initiate Closure
Increase the time frame to initiate closure of CCR surface impoundments and landfills from one year (as required in EPA’s proposed rule) to at least three years and add a provision to allow States the flexibility to approve extensions beyond the three years based on a case-by-case review of site-specific conditions.

Time Frame to Complete Closure
Allow States the flexibility to approve time frames to complete closure of CCR surface impoundments and landfills beyond the EPA’s proposed 180-day time frame based on a case-by-case review of site-specific conditions, including but not limited to the size of the unit.

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DATE SUBMITTED: 05/06/13

SHORT TITLE: Revisions to 10 CFR Part 61 Adobe Acrobat PDF Document

SUBMITTED TO: U.S. Nuclear Regulatory Commission

OFFICE PREPARING: Office of Waste

STAFF CONTACT: Brad Broussard

SUMMARY OF COMMENTS:

  • Use of waste classification tables in §336.362 or a site-specific performance assessment for determining the types and classes of waste eligible for receipt
  • Compatibility categories for new provisions relating to performance period, compliance period, and waste acceptance criteria
  • Clarification of performance period (after the 10,000 yr. compliance period)

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DATE SUBMITTED: 01/07/13

SHORT TITLE: Proposed revisions to 10 CFR Part 61, Licensing Requirements for Land Disposal of Radioactive Waste. Adobe Acrobat PDF Document

SUBMITTED TO: U.S. Nuclear Regulatory Commission

OFFICE PREPARING: Office of Waste

STAFF CONTACT: Brad Broussard

TCEQ COMMENTS:

Proposed 61.7 Concepts

Comments: This proposed provision seems to allow waste acceptance criteria to be established from the results of a site-specific analysis for any "land disposal facility." In addition, it appears that in the context of this revision a "near-surface disposal facility" is different than a land disposal facility. This implies that waste acceptance criteria established from a site-specific analysis is the only approach that has to be taken for meeting the performance objectives. However, Section 5.2.7 of the Part 61 Regulatory Basis document states that the NRC is proposing Option 3 - Generic Waste Classification or Site-Specific Waste Acceptance where a hybrid approach is taken that would allow licensees to use either the results of the site-specific technical analyses set forth in 10 CFR 61.13 or the waste classification requirements in 10 CFR 61.55.

The proposed language in 61.7(d) should be clarified in guidance or expanded in rule to indicate that this hybrid approach should incorporate both the waste classification tables and an approved site-specific analysis in determining waste acceptance criteria.

Proposed 61.2 Definitions: Period of Performance

Comment: The new proposed definition of performance period indicates that the performance objectives of § §61.41(b) and 61.42(b) must be met. The standard that has to be met for the second tier analysis is still too subjective. Guidance developed that provides instruction on conducting a second tier analysis should state how the ALARA analysis is demonstrated. This may proide etter direction for regulators as to how to implement the proposed definition and the proposed § 61.41(b) and § 61.42(b) revisions.

Compatability

Comment: The current compatibility category for §61.41 is category A. If the NRC chooses to maintain this category with the new revisions to §61.41, specifically performance period analyses demonstrating ALARA, the NRC should provide direction in the Part 61 supporting guidance for conducting an ALARA analysis that meets the proposed requirements in §61.41(b).

The current compatibility category for the waste classification tables in §61.55 is category B. If site-specific analysis is used to determine waste acceptance criteria, the NRC should maintain the same compatibility category.

The current compatibility category for §61.2 relating to definitions is category B. However, §61.7 has no compatibility category but the proposed revisions address conducting a performance assessment, an intruder assessment, site-specific analyses for long-lived waste, and in developing waste acceptance criteria. Careful consideration should be given to the compatibility category for §61.7. Stakeholders should be provided the opportunity to provide input on compatibility categories as they are determined by the NRC Standing Committee on Compatibility.

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DATE SUBMITTED: 02/21/12

SHORT TITLE: Non-Hazardous Secondary Materials That Are Solid Waste

SUBMITTED TO: U.S. Environmental Protection Agency (EPA)

OFFICE PREPARING: Office of Compliance and Enforcement

STAFF CONTACT: Lori Wilson

SUMMARY OF COMMENTS:
EPA’s Reconsideration rulemaking does not go far enough in addressing a major environmental problem of scrap tires being dumped nationwide. EPA’s current stance is a disincentive for the economic recovery and reuse of tires and would discourage the development of markets for recycled material. Texas recommends that EPA revise its Reconsideration rule by defining “established tire collection program” more broadly to benefit tire collection programs nationwide. EPA should expand the scope of established tire collection programs to include all scrap tires (regardless of when and how the tire is collected). EPA should develop a regulatory mechanism for tires to be classified as a “solid waste” and then exit that classification when a set of conditions is met. Under this Alternative Approach, tires would be solid wastes when they are abandoned and remain in the environment as a health and nuisance hazard. However, tires would fall outside the solid waste classification when they are collected under a legitimate collection program and stored properly for reuse or to be burned for energy recovery. To implement the Alternative Approach, EPA would allow qualified recovery programs to step into the place of the original generator by recapturing control over abandoned tires and properly storing them, prior to their being recycled or burned for energy recovery. TCEQ provides five compelling reasons why EPA should promulgate a final clarification rule which allows all collected scrap tires to fall within the scope of an established tire collection program. Allowing all tires to be burned in combustion units is better for the environment, safer for the public, better for regulators, good public policy, and easier for tire processors.

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DATE SUBMITTED: 10/20/11

SHORT TITLE: Rulemaking on the Definition of Solid Waste

SUBMITTED TO: U.S. Environmental Protection Agency (EPA)

OFFICE PREPARING: Office of Waste

STAFF CONTACT: Lynn Bell

SUMMARY OF COMMENTS:
The TCEQ supports the proposed regulations for replacing the “Transfer Based Exclusion” with a “Remanufacturing Exclusion”; revising the “Reclamation under the Control of the Generator”; and inclusion of “Legitimacy Criteria” in the regulations because they are more easily enforced or they provide clearer definitions of the regulatory intent. In general, the TCEQ supports the proposal for the variances and non-waste determinations that requires a re-application for the variance or determination in the event of a change in circumstances affecting the material. TCEQ also supports the proposal requiring facilities to renew variances at a prescribed frequency, in order to verify that the variance is still valid and that the holder of the variance is meeting the requirements of the rule. However, TCEQ suggests a renewal period of every five years, commencing from the original date of issuance, rather than reviewing all variances for renewal every even-numbered year, in order to reduce resource needs. We also recommend that the authorized state reserve the right to review variances on a more frequent schedule, if warranted by the facility’s compliance history or related enforcement issues. In addition, the TCEQ does not agree that EPA concurrence should be required prior to issuance by the state for all variance determinations.

The proposal also revises the Criteria for Partial Reclamation Variances, which the TCEQ generally supports. However, we are providing comments on the revision in portions where they may affect existing variances that the state has issued, particularly in the area of refining catalyst reclamation. The TCEQ does not support the proposed removal of “Other Relevant Factors” from the criteria list, as this provides opportunities to review such considerations as compliance history in combination with the other relevant factors.

The TCEQ supports the revision of the Non-Waste Determination portion of the rule to require affected facilities to consider existing exclusions before pursuing a non-waste determination petition. Many of these requests are filed as informal inquiries or staff can direct the inquiry to existing exemptions that are self-implementing. However, the TCEQ does not support the proposed revision to require public participation when a non-waste determination request is denied. Adding these requirements to the process adds no benefit and would be unduly burdensome.

Lastly, the TCEQ is commenting on the addition of recycling language to the Boiler and Industrial Furnace regulations that may be interpreted to require certain fully regulated burners to meet the recycling criteria. We are requesting clarification of this issue and revision of the language.

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DATE SUBMITTED: 09/30/11

SHORT TITLE: Municipal Solid Waste (MSW), Recycling, and Source Reduction Measurement in the U.S.

SUBMITTED TO: U.S. Environmental Protection Agency (EPA)

OFFICE PREPARING: Office of Waste

STAFF CONTACT: Brent Wade

SUMMARY OF COMMENTS:
The TCEQ defines municipal solid waste more broadly than EPA by including construction and demolition waste as well as any waste generated by the non-industrial service sector. The EPA should consider all these waste streams, not just those generated from residential activities, to develop useful information. A consistent data basis would allow the TCEQ to compare waste and recycling data at the state level to national data.

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DATE SUBMITTED: 05/27/11

SHORT TITLE: 2011 Hazardous Waste Report: Notification of Regulated Waste Activity, and Part A Hazardous Waste Permit Application and Modification

SUBMITTED TO: U.S. Environmental Protection Agency (EPA)

OFFICE PREPARING: Office of Permitting and Registration

STAFF CONTACT: Caroline Wersterfer

SUMMARY OF COMMENTS:
The TCEQ offers the following comments:
• EPA does not give a clear description of the proposed use of the Waste Minimization data. If EPA has a planned use for the data, it would be useful to describe that plan so that the reporting burden can be accurately identified in concert with the data needs. If there is no planned use, then no additional amount of reporting burden is justifiable.
• The draft 2011 Hazardous Waste Report Instructions and Forms guide proposed to add an expanded list of waste minimization codes and definitions of “waste minimization” and “sustainable materials management.” The proposed definition may lead to confusion as it does not define the difference between source reduction (pollution prevention) and waste minimization. By EPA’s own definitions, source reduction is exclusive of waste minimization.
• EPA asks whether hazardous waste generators should report on-going waste minimization efforts, only new efforts, or both? If the purpose is to identify only new projects which resulted in waste minimization, EPA should establish a new baseline in which generators should report all on-going projects as new projects. In subsequent years, EPA should only collect new waste minimization projects.
• Among its examples of RCRA hazardous wastes to be reported, EPA includes an example of waste derived from the management of non-hazardous waste. TCEQ recommends deleting this example. The management of a non-hazardous waste does not produce a hazardous waste. Inclusion of this example may cause confusion among responding generators.

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DATE SUBMITTED: 11/19/10

SHORT TITLE: Hazardous and Solid Waste Management System; Disposal of Coal Combustion Residuals From Electric Utilities

SUBMITTED TO: U.S. Environmental Protection Agency (EPA)

OFFICE PREPARING: Office of Permitting and Registration

STAFF CONTACT: Kari Bourland

SUMMARY OF COMMENTS:
The TCEQ does not support regulating CCRs under Subtitle C of RCRA. Should EPA determine that federal regulation of CCRs is necessary and appropriate, TCEQ recommends that CCRs be regulated under Subtitle D of RCRA rather than Subtitle C, as regulation of CCRs under Subtitle C could negatively impact the beneficial use of CCRs.

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DATE SUBMITTED: 08/03/10

SHORT TITLE: Identification of Non-Hazardous Secondary Materials That Are Solid Waste

SUBMITTED TO: U.S. Environmental Protection Agency (EPA)

OFFICE PREPARING: Office of Permitting and Registration

STAFF CONTACT: Steve Hagle

SUMMARY OF COMMENTS:
EPA’s proposed regulation clarifies which non-hazardous secondary materials are solid wastes under the Resource Conservation and Recovery Act (RCRA) when burned as fuel or used as ingredients in combustion units. The RCRA definition of “solid waste” is used to determine whether a combustion unit is subject to the emission standards for solid waste incineration units issued under Section 129 of CAA. The TCEQ is concerned that EPA’s proposal to clarify “solid waste” will subject combustion sources that utilize certain nonhazardous material with “Btu” or material value as fuel to additional CAA requirements with little or no environmental benefits. The TCEQ is specifically concerned that Portland cement kilns burning scrap tires (shredded or whole tires) will be subject to additional air standards and regulations under this proposal and negatively impact our existing used tire management program. The TCEQ suggests that the proposed rule specifically exempt non-hazardous secondary materials such as scrap tires from the definition of solid waste in the final rule. We also suggest that EPA not consider placement of tires in a waste pile as “disposal" and/or abandonment for the purpose of designation of these materials as solid waste and subjecting them to the CAA regulations. This exemption will facilitate their use as fuel and ingredient in Portland cement kilns and at the same time help effectively manage scrap tires.

Since EPA’s proposed solid waste definition narrows what materials would, when combusted, trigger the applicability of the newly-proposed standards under CAA Section 129, the exemption of scrap tires from the proposed definition of “solid waste” in 40 CFR Part 241 will not impact TCEQ’s ability to continue to regulate scrap tires as solid wastes under State Subtitle D programs. Such exemption would not affect Texas’ ability to classify and regulate scrap tires under existing state laws or under RCRA Subtitle D for purposes of generation, transportation, taxation, and management standards.

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DATE SUBMITTED: 02/26/2010

SHORT TITLE: Draft Recommended Interim Preliminary Remediation Goals for Dioxin in Soil at CERCLA and RCRA Sites

SUBMITTED TO: U.S. Environmental Protection Agency (EPA)

OFFICE PREPARING: Office of Compliance and Enforcement

STAFF CONTACT: Greg Tipple, P.G.

SUMMARY OF COMMENTS:
A series of toxicologically-based comments conclude that EPA should not adopt revised PRGs for dioxins in soils at Federal Superfund and RCRA sites until such time as it completes the reassessment of dioxin toxicity. The reassessment, when concluded, will be based on a formal peer review of all dioxin toxicity studies and other data that are presently available. The PRGs that EPA is proposing are not scientifically defensible since they are not based upon the best information regarding dioxin toxicity that is available. EPA is proposing to substantially reduce the PRGs for dioxin in soils based on old toxicity studies, rather than waiting until it can formally adopt new, peer-reviewed toxicity values. Specifically, the carcinogenic oral slope factor (SFo) and the non-carcinogenic chronic minimum risk level (MRL) toxicity factors used in the calculations for the proposed interim PRGs are 25 and 12 years old, respectively. The TCEQ comments identify more current documents pertaining to dioxin toxicity which EPA should have considered. EPA provided only a 50-day comment period on this complex topic. A TCEQ comment requests that EPA extend the comment period by at least 60 days.

A series of implementation-based comments also conclude that EPA should not issue revised PRGs for dioxin in soils until such time as it completes the final reassessment of dioxin toxicity. However, if EPA decides to issue the interim PRGs, then it should, previously or concurrently, release additional guidance that more specifically discusses how the interim PRGs are to be applied to active and closed dioxin sites. Also, in such guidance, EPA should clarify that it does not intend to use revised PRGs, prior to its completion of the final dioxin reassessment, to conclude that any site, appropriately evaluated and/or remediated in response to its 1998 dioxin PRGs, requires additional response to be protective of human health.

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