UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON , D.C

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# . OFFICE OF SOLID WASTE AND EMERGENCY RESPONSE
MEMORANDUM 

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FROM:

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Correction ofInadvertent Errors in the Disposal ofCoal Combustion Residuals from Electric Utilities (Tier 1; SAN 4470; RIN 2050-AE81) Mathy Stanislaus

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Joel Beauvais

# ~~ Office ofPolicy (1 A**~** MaryKayL Office ofGeneral Counsel (2366A) Gina McCarthy (1 lOIA) Administrator

We recommend making six changes to the Coal Combustion Residuals Final Rule that was signed on December 19 , 20 14, but has not yet been published in the Federal Register. These changes insert regulatory text in instances in which it was inadvertently omitted from the final rule, make minor revisions to correct inadvertent errors, correct potentially confusing cross references, and clarify preamble language. This memorandum is submitted per OGC and OP guidance on changes to rule language after the rule has been signed by the Administra tor but before it has been published in the Federal Register. 1
1. Insertion ofregulatory language to clarify the requirement that a facility must post all groundwater monitoring results on the facility ' s publicly accessible internet site. First, regulatory language needs to be inserted to conform the regulatory text with the preamble to require all groundwater monitoring results be posted on the facility's publicly accessible internet site. The preamble discussion is very clear that all groundwater monitoring data are to be made available on the publicly accessible internet site. For example, on page 115 ofthe prepublication version ofthe preamble to the final rule: It is more consistent with EPA's obligations under RCRA to put in place the additional protections that, based on the information currently available, are needed to protect health

1 Memorandum from Ann Klee , General Coun sel, and Brian Mannix, Associate Administrator for the Office of Policy, Economics and Innovation , Changes to Rul e Document s Prepared/or the Administrator ' s Signature, July 25, 2006. 1and the environment. As part ofthose requirements, EPA has developed a number of 

### provisions designed to facilitate citizens to enforce the rule pursuant to RCRA section 7002. Chief among these is the requirement topubliclypost monitoring data, along with critical documentation o

_ f facility operations, so that the public will have access to the information to monitor activities at CCR disposal facilities. (italics added)
In addition, on page 129 ofthe pre-publication version ofthe preamble to the final rule:
As repeatedly discussed throughout this preamble, under section 4004(a) EPA must be able to demonstrate, based on the record available at the time the rule is promulgated that the final rule provisions will achieve the statutory standard. EPA explained in the proposal that a key component ofEPA's support for determining that the rule achieves the statutory standard is the existence of a mechanism for states and citizens to monitor the situation, such as when groundwater monitoring shows evidence of potential contamination , so that they can determine when intervention is appropriate. The existence ofeffective oversight measures provides critical support for the statutory finding, particularly with respect to some ofthe more flexible alternatives EPA has adopted in certain ofthe technical standards in response to commenters ' requests for greater flexibility

. These "transparency" requirements serve as a key component by ensuring that the entitiesprimarily responsible for enforcing the requirements have access to the information necessary to determine whether enforcement is warranted Unlike a federal or state regulatory authority, private citizens cannot access a private facility to conduct inspections. (italics added) Finally, on page 351 ofthe pre-publication version ofthe preamble to the final rule: Consistent with the proposal , the final rule also requires that the owner or operator ofthe CCR facility annually certify that each CCR unit is in compliance with the groundwater monitoring and corrective action provisions and provide a copy ofthis certification to the State Director. Because this is a self-implementing rule that relies on citizen enforcement, it is important for the owner or operator ofthe facility to periodically document that they are in compliance with the existing groundwater monitoring requirements, and an annual certification is the easiest and most effective way to achieve this. While the groundwater monitoring data will be made available on the owner or operator'spublicly accessible website and in the operating record of the facility, the analysis ofthese data is complicated and requires a certain level of scientific expertise to analyze the data correctly. (italics added) Nevertheless, the conforming text was inadvertently omitted from the rule. We recommend adding the phase, "in addition to all the monitoring data obtained under §§257.90-257.98 " to the regulatory text at 40 CFR 257.90( e). The regulatory text will clearly reflect EPA ' s stated position as reflected throughout the preamble to the final rule. 2. Insertion ofthe word "coal" in the definition of a CCR landfill. Secondly, as written, all underground and surface mines are excluded from the definition ofCCR landfill, when it was clear that we intended to exclude only coal mines. The word "coa l" , 2therefore, needs to be added to the definition of" CCR landfill" at 40 CFR 257.2 and 257.53. The Scope and Purpose section ofthe final rule [40 CFR 257.50(h)] states that " This subpart does not apply to CCR placement at active or abandoned underground or surface coal mines. " Further, EPA made its intention clear in many places in the preamble, particularly on page 194 of the pre-publication version ofthe final rule which states: Severa l commenters also suggested that the definition of a CCR landfill should explicitly exclude the use ofCCR at surface coal mining and reclamation operations to reflect the Agency ' s intention not to cover such activities. The Agenc y agrees and has revised the definition to explicitlyprovide that the term CCR landfill does not include the use of CCR at coal mining and reclamation operations. (ita lics added) The addition ofthe word " coal" to the definition of " CCR landfill " will make the definition consistent with EPA ' s stated intent. 3. Insertion ofregulatory text to make it clear that CCR surface impoundments may either retrofit with a composite liner or close. Third, regulatory language is needed to eliminate an inconsistency between the regulatory text and preamble statements regarding the option for faci lities to retrofit or close an existing CCR surface impoundment. The preamble is clear that such facilities ha ve the option to retrofit or close the unit; however, the regulatory text does not explicitly provide for the retrofit option.
For example, on page 386 ofthe prepublication version ofthe preamble to the final rule: Ifcorrective action is triggered, within three months the owner or operator must initiate an assessment ofcorrective measures. Ifthe CCR unit is an unlined surface impoundment, the unit must also initiate closure or begin to retrofit the unit. The owner or operator could also simultaneously use these 3 months to demonstrate that the statistica lly significant increase found during assessment monitoring was due to another source or sampling and analysis error. (italics added)
On page 458 ofthe prepublication version ofthe preamble, the Agency specifies what is meant by retrofit ofan unlined CCR surface impoundment, specifica lly, the removal of all CCR from the unit followed by the installation of a composite liner:

...In the final rule , EPA is allowing unlined CCR surface impoundments to continue to operate for the remainder ofthe active life, provided that the facility documents through groundwater monitoring that the CCR surface impoundment is not contaminating groundwater

. However, ifgroundwater monitoring at the facility demonstrates that the unlined CCR surface impoundment has exceeded any groundwater protect ion standard, the owner or operator must initiat e corrective action, and either remove all CC R

from the unit and install a composite liner (i.e., "retrofit") or close within five years. In a departure from the proposed rule, CCR surface impoundments less than 40 acres may receive one two

-year extension, providing for a maximum of seven years to complete closure. Units greater than 40 acres may receive up to five two

-year extensions providing a maximum of 15 years to complete closure. These units are also eligible for alternative closure timeframes to account for site specific operational constra ints. (italics added)
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### It is therefore necessary to rename 40 CFR 257.102 to include "retrofit" and to add paragraph (k) "Criteria to retrofit an existing CCR surface impoundment" to 40 CFR 257.102. In addition, it is necessary to make conforming changes to add a definition ofretrofit, and the appropriate recordkeeping, notification, and internet posting requirements. As a result ofthese suggested changes, the regulatory text will clearly reflect EPA's stated position in the preamble that surface impoundments have the option to retrofit or close.
4. Minor revisions to paragraphs specifying requirements that apply when a deficiency or release from a CCR unit is identified during a structural stability assessment or annual inspection. Fourth, minor revisions are necessary in a number ofrule paragraphs that specify the requirements that apply when a deficiency ofor release from a CCR unit is identified during a structural stability assessment or annual inspection. The final rule clearly requires that the owner or operator ofthe CCR unit remedy the deficiency or release as soon as feasible; however, the associated recordkeeping, notification and internet website requirements require the preparation and making publicly available ofan "action plan." Since an "action plan" is not required, this requirement should be removed from the recordkeeping, notification, and internet website requirements and replaced with language to require that both the deficiency or release and the

" documentation ofcorrective measures taken" be made available to the public. The rule sections affected by this change in 40 CFR 257.73, 257

.74, 257.83, 257.84, 257.105, 257.106, and 257.107.
5. Deletion ofpotentially confusing cross references to timeframes for completing closure.
Fifth, the regulatory text contains cross references to the required timeframes for completing the closure ofCCR surface impoundments. The cross references point only to two ofthe circumstances where closure must be initiated and not the third. To avoid any possible confusion, we recommend deleting any such cross references. Specifically, it is optimal to strike the existing regulatory reference to "conducted pursuant to either paragraph (e)(1) or (e)(2) of this section." This revision would apply both to 40 CFR 257.102(f)(l)(i) and (ii).
6. Minor revision to the Preamble to clarify that lead does not have an MCL.
Finally, we inadvertently omitted lead from the discussion ofconstituents on Appendix IV that do not have a maximum contaminant level (MCL). Lead does not have an MCL and therefore should be mentioned along with cobalt, lithium and molybdenum. The groundwater protection standards for lead will therefore be the same as for all other constituents without MCLs, i.e., background level(s). No changes are required in the regulatory text. Upon your approval ofthese corrections, we will make these revisions prior to publication ofthe rule in t he Federal Register. Please let me know ifyou have any questions about these proposed corrections.

4I approve the following corrections (additional text is shown in italics, deleted text in strike out) to the Coal Combustion Residuals Final Rule. The attachment to this memorandum contains the pages with the regulatory and preamble corrections as described in the following paragraphs. These correct ions in the attachment appear in redline and strikeout. The page numbers in parentheses indicate the page numbers on which the corrections are found. At 40 CFR 257.90(e): (3) In addition to all the monitoring data obtained under §§257.90-25 7.98, a A summary including the number ofgroundwater samples that were collected for analysis for each background and downgradient well, the dates the samples were collected, and whether the sample was required by the detection monitoring or assessment monitoring programs; (Page 669) At 40 CFR 257.2: CCR landfill or landfill means an area ofland or an excavation that receives CCR and which is not a surface impoundment, an underground injection well , a salt dome formation, a salt bed formation, an underground or surface coal mine, or a cave. For purposes ofthis subpart, a CCR landfill also includes sand and gravel pits and quarries that receive CCR, CCR piles, and any practice that does not meet the definition of a beneficial use ofCCR. (Page 603) At 40 CFR 257.53: CCR landfill or landfill means an area ofland or an excavation that receives CCR and which is not a surface impoundment, an underground injection well, a salt dome formation, a salt bed formation, an underground or surface coal mine, or a cave. For purposes ofthis subpart, a CCR landfill also includes sand and gravel pits and quarries that receive CCR, CCR piles, and any practice that does not meet the definition of a beneficial use ofCCR. (Page 610) At 40 CFR 257.53 Definitions Retrofit means to remove all CCR and contaminated soils and sediments from the CCR surface impoundment, and to ensure the unit complies with the requirements in§ 257. 72. (Page 618) At 40 CFR 257. lOl(a)(l): 

### § 257.101 Closure or retrofit 

### of CCR units 

### leedfills eed CCR suFfeee impeuedmeets. (a) The owner or operator of an existing unlined CCR surface impoundment, as determined under§ 257.71(a), is subject to the requirements ofparagraph (a)(l) ofthis section. (1) Except as provided by paragraph (a)(3) ofthis section, if at any time after [INSERT DATE 6 MONTHS AFTER DATE OF PUBLICATION IN THE FEDERAL REGISTER] an owner or operator of an existing unlined CCR surface impoundment determines in any sampling event that the concentrations ofone or more constituents listed in appendix IV to this 

### part are detected at statistically significant levels above the groundwater protection standard established under§ 257.95(h) for such CCR unit, within six months ofmaking such

5determination, the owner or operator ofthe existing unlined CCR surface impoundment must cease placing CCR and noneCCR waste streams into such CCR surface impoundment and either retrofit or close the CCR unit in accordance with the requirements of§ 257.102. (2) An owner or operator of an existing unlined CCR surface impoundment that closes in accordance with paragraph (a)(l) ofthis section must include a statement in the notification required under§ 257.102(g) or (k)(5) that the CCR surface impoundment is closing or retrofitting under the requirements ofparagraph (a)(l) ofthis section. (3) The timeframe specified in paragraph (a)(l) ofthis section does not apply ifthe owner or operator complies with the alternative closure procedures specified in § 257.103. (4) At any time after the initiation of closure underparagraph (a)(l) of this section, the owner or operator may cease closure activities and initiate a retrofit of the CCR unit in accordance with the requirements of §257.102(k). (Page 698-99) At 40 CFR 257.102 

### § 257.102 Criter ia for condu . cting the closure or retrofit of CCR units landfills and CCR suFfeee impoundments. (a) Closure of a CCR landfill, CCR surface impoundment, or any lateral expansion of a CCR unit must be completed either by leaving the CCR in place and installing a final cover system or through removal ofthe CCR and decontamination ofthe CCR unit, as described in paragraphs (b) through (j) of this section. Retrofit of a CCR surface impoundment must be completed in accordance with the requirements inparagraph (k) of this section. (Page 701) (k) Criteria to retrofit an existing CCR surface impoundment. (1) To retrofit and existing CCR surface impoundment, the owner or operator must: (i) First remove all CCR, including any contaminated soils and sediments from the CCR unit; and (ii) Comply with the requirements in§ 257. 72. (iii) A CCR surface impoundment undergoing a retrofit remains subject to all other requirements of this subpart, including the requirement to conduct any necessary corrective action. (2) Written Retrofit Plan. 

### (i) Content of the plan. The owner or operator must prepare a written retrofitplan that describes the steps necessary to retrofit the CCR unit consistent with recognized and generally accepted good engineeringpractices. The written retrofitplan must include, at a minimum, all of the following information: (A) A narrative description of the specific measures that will be taken to retrofit the CCR unit in accordance with this section. (B) A description of theprocedures to remove all CCR and contaminated soils and sediments from the CCR unit.

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### (C) An estimate of the maximum amount of CCR that will be removed aspart of the retrofit operation. (D) An estimate of the largest area of the CCR unit that will be affected by the retrofit operation. (E

) A schedule for completing all activities necessary to satisfy the retrofit criteria in this section , including an estimate of the year in which retrofit activities of the CCR unit will be completed. (ii) Time-frames (or preparing the initial written retrofitplan. (A) No later than 60 days prior to date of initiating retrofit activities , the owner or operator mustprepare an initial written retrofitplan consistent with the requirement s s pecified inparagraph (k)(2) of this section. For purposes of this subpart, initiation of retrofit activities has commenced 

### if the owner or operator has ceased placing waste in the unit and completes any of thefollowing actions or activities: (1) 

### Taken any steps necessary to implement the written retrofitplan; (2) Submitted a completed application for any required state or agencypermit orpermit modification; or (3) Taken any steps necessary to comply with any state or other agency standards that are a prerequi site, or are otherwi se applicable, to initiating or completing the retrofit of a CCR unit. (B) The owner or operator has completed the written retrofitplan when the plan, including the certification required byparagraph (k)(2)(iv) of this section, has beenplaced in the facility ' s operating record as required by § 257

. 1050)(1)

. (iii) Amendment of a written retrofit plan. (A) The owner or operator may amend the initial or any subsequent written retrofitplan at any time

. (B) The owner or operator must amend the written retrofitplan whenever: (1) 

### There is a change in the operation of the CCR unit that would substantially affect the written retrofitplan in effect ; or (2) Before or after retrofit activities have commenced, unanticipated events necessitate a revision of the written retrofitplan. (C ) The owner or operator must amend the retrofitplan at least 60 days prior to aplanned change in the operation of thefacility or CCR unit, or no later than 60 days after an unanticipated event requires the revision of an existing written retrofitplan. 

## If a written retrofit plan is revised after retrofit activities have commenced for a CCR unit , the owner or operator must amend the current retrofitplan no later than 30 days following the triggering event. (iv) The owner or operator of the CCR unit must obtain a written certification.from a qualified professional engineer that the activities outlined in the written retrofitplan, including any amendment of theplan , meet the requirements of this section. (3) Deadline for completion of activities related to the retrofit ofa CCR unit

. Any CCR s urface impoundment that is being retrofitted must complete all retrofit activities within the same

7time frames and procedures specified for the closure of a CC R surface impoundment in § 

### 257. 102(/) or , where applicable,§ 257.103. (4) Upon com pletion , the owner or operator must obtain a certification.from a qualified professional engineer verifying that the retrofit activities have been completed in accordance with the retrofitplan specified inparagraph (k)(2) of this section and the requirements of this section. (5) No later than the date the owner or operator initiates the r etr ofit of a CCR unit , the owner or operator must prepare a notification of intent to retrofit a CCR unit. The owner or operator has completed the notification when it has beenplaced in the facility ' s operating record as required by§ 257.1050)(5). (6) Within 30 days of completing the retrofit activities specified inparagraph (k)(l) of this section, the owner or operator must prepare a notification of completion of retrofit activities. The notification must include the certification by a qualified professional engineer as required byparagraph (k)(4) of this section. The owner or operator has completed the notification when it has beenplaced in the facility's operating record as required by § 257.105(j)(6). (7) At any time after the initiation of a CCR unit retrofit , the owner or operator may cease the retrofit and initiate closure of the CCR unit in accordance with the requirements of § 25 7. 102. (8) The owner or operator of the CCR unit must comply with the retrofit recordkeeping requirements specified in§ 25 7. 1050), the retrofit notification requirements specified in § 25 7. 1060), and the retrofit internet requirements specified in § 25 7. 1070)

. (Pages 714

- 717) At 40 CFR 25 7.105 Recordkeeping Requirements (j) Retrofit criteria. The owner or operator of a CCR unit subject to this subpart mustplace the following information, as it becomes available, in the facility 's operating record: (1) The written retrofitplan, and any amendment of the plan, as required by§ 257.102(k)(2), except that only the most recent retrofitplan must be maintained in the facility ' s operating record irrespective of the time requirement specified inparagraph (b) of this section. (2) The notification of intent that the retrofit activities willproceed in accordance with the alternativeprocedures in § 257.103. (3) The annualprogress reports required under the alternative retrofit requirements as required by § 257.103. (4) The written demonstration(s), including the certification in § 25 7 .102(/)(2}(iii),for a time extension for completing retrofit activities as required by § 25 7. 102(k)(3). (5) The notification of intent to initiate retrofit of a CC R unit as required by § 257. J02(k)(5). (6) The notification of completion of retrofit activities as required by§ 25 7. 102(k)(6)

. (Pages 730-731)

8At 40 CFR 257.106 Notification Requirements 

### (j) Retrofit criteria. The owner or operator of a CCR unit subject to this subpart must notify the State Director and/or appropriate Tribal authority when information has beenplaced in the operating record and on the owner or operator'spublicly accessible internet site. The owner or operator must: (1) 

### Provide notification of the availability of the written retrofitplan, and any amendment of the plan , specified under§ 257.105(j)(l). (2) Provide notification of intent to comply with the alternative retrofit requirements specified under § 25 7 .105(j)(2). (3) The annualprogress reports under the alternative retrofit requirements as required by§ 257.105(j)(3)

. (4) Provide notification of the availability of the demonstration(s)for a time extension for completing retrofit activities specified under§ 257.105(j)(4). (5) Provide notification of intent to initiate retrofit of a CCR unit specified under§ 257.105(j)(5)

. (6) Pr ovide notification of completion of retrofit activities specified under§ 257.105(j)(6). (Pages 736-73 7) 40 CFR 257

.l 07 Publicly accessible internet site requirements (f) 

### Retrofit criteria. The owner or operator of a CCR unit subject to this subpart mustplace thefollowing information on the owner or operator ' s CCR website: (1) 

### The written retrofitplan, and any amendment of the plan, specified under§ 257.105(;)(1). (2) The notification of intent to comply with the alternative retrofit requirements as required by§ 257.1050)(2). (3) The annualprogress reports under the alternative retrofit requirements as required by§ 257.105(;)(3). (4) The demonstration(s)for a time extension for completing retrofit activities specified under§ 257.105(;)(4)

. (5) The notification of intent to retrofit a CCR unit specified under§ 257.105(j)(5). (6) The notification of completion of retrofit activities specified under§ 257.105(j)(6). (Page 742) At 40 CFR 257

.73(d)(2) and 257.74(d)(2) : (2) The periodic assessment described in paragraph (d)(l ) ofthis section must identify any 

### structural stability defici encies associated wit h t he CCR unit in addition to recommending correct ive measures . 

### Ifa deficiency or a release is identified during the periodic assessment, the
9owner or operator unit must remedy the deficiency or release as soon as feasible and prepare 

### documentation detailing the corrective measures taken.
(Pages 642 and 651) At 40 CFR 257.83(b)(5) and 257.84(b)(5): (5) 

### If a deficiency or release is iden tified during an inspection, the owner or operator must remedy the deficiency or release as soon as feasible and prepare documentation detailing the corrective measures taken. (Pages 664 and 667)
At 40 CFR 257.105(f)(l 1) and (g)(7): (f) Design criteria. The owner or operator of a CCR unit subject to this subpart must place the following information, as it becomes available, in the facility ' s operating record: ( 11) The action plan Documentation detailing the corrective measures taken to remedy structural stability deficiencies the deficiency or release as required by§§ 257.73(d)(2) and 257.74(d)(2). (g) Operating criteria. The owner or operator ofa CCR unit subject to this subpart must place the following information, as it becomes available, 

### in the facility's operating record: (7) The action plan Documentation detailing the corrective measures taken to remedy the deficiency or release as required 

### by§§ 257.83(b)(5) and 257.84(b)(5). (Pages 726 and 727)
At 40 CFR 257.106(f)C10) and (g)(6): (f) Design criteria. The owner or operator of a CCR unit subject to this subpart must notify the State Director and/or appropriate Tribal authority when information has been placed in the operating record and on the owner or operator's publicly accessible internet site. The owner or operator must: (10) Provide notification ofthe availability ofthe aetion plan documentation detailing the corrective measures taken to remedy struetlH'al stability defieieHeies the deficiency or release specified under§ 257.105(f)(ll). (g) Operating criteria. The owner or operator of a CCR unit subject to this subpart must notify the State Director and/or appropriate Tribal authority when information has been placed in the operating record and on the owner or operator's publicly accessible internet site. The owner or operator must: (6) Provide notifica tion ofthe availability ofthe aetion plan documentation detailing the corrective measures taken to remedy the deficiency or release specified under 

### § 257.105(g)(7). (Pages 733 and 734)

10At 40 CFR 257.107(0(10) and (g)(6): (f) Design criteria. The owner or operator of a CCR unit subject to this subpart must place the following information on the owner or operator's CCR website: (10) The actioe. plan documentation detailing the corrective measures taken to remedy structural stability deficiee.cies the deficiency or release specified under § 257.105(f)( 11 ). (g) Operating criteria. The owner or operator of a CCR unit subject to this subpart must place the following information on the owner or operator's CCR website: (6) The actioe. plan documentation detailing the corrective measures taken to remedy the deficiency or release specified under§ 257.105(g)(7).
(Page 739) At 40 CFR 257. l 02(0: (f) Completion ofclosure activities. (1) Except as provided for in paragraph (f)(2) ofthis section, the owner or operator must complete closure ofthe CCR unit: (i) For existing and new CCR landfills and any lateral expansion ofa CCR landfill, within six months of commencing closure activities. pursuant to either paragraph (e)(l) or (e)(2) ofthis sectioe.. (ii) For existing and new CCR surface impoundments and any lateral expansion ofa CCR surface impoundment, within five years of commencing closure activities. pursuant to eitlier paragraph (e)(l) or (e)(2) ofthis sectioe..
(Page 710) Preamble Modifications On page 370 ofthe pre-publication version ofthe preamble to the final rule, insert the word "lead" in two places. For each Appendix IV constituent that is detected, a ground water protection standard must be set. The groundwater protection standards must be the MCL or the background concentration level for the detected constituent, whichever is higher. 

### Ifthere is no MCL promulgated for a detected constituent, then the groundwater protection standard must be set at background. The proposed rule would have allowed the owner or operator to establish an alternative groundwater protection standard for constituents for which MCLs have not been established provided that the alternative groundwater protection standard has been certified by an independent registered professional engineer and the state has been notified that the alternative groundwater protection standard has been placed in the operating record and on the owner' s or operator's publicly accessible internet site. This provision had been adopted from the part 258 regulations, but was determined to be inappropriate in a self

- implementing rule, as it was unlikely that a facility would have the scientific expertise necessary to conduct a risk assessment, and was too susceptible to potential abuse. Additionally, numerous comments were received suggesting that only those constituents with MCLs be included in Appendix IV. The

11comm.enters were concerned that only MCLs are enforceable. With the exception ofcobalt, 

### lead, lithium and molybdenum (included on Appendix IV because oftheir relevance in the risk assessment and damage cases), all Appendix IV constituents have an MCL. In the proposed rule, as stated above, owner or operators were allowed to establish certain types of alternative groundwater protection standards. In the final rule, if a constituent has no MCL (i.e., cobalt, lead, lithium and molybdenum), their groundwater protection standards will be their background levels. These background standards are sufficient ly precise that they are enforceable. (Page 370)
I approve the corrections li sted above to the Coal Combustion Residuals Final Rule:

# Gi**~** MAR 202015

Administrator

Attachment

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