1



# Comment Summary and Response Document

Hazardous and Solid Waste Management System;

Identification and Listing of Special Wastes; Disposal of

Coal Combustion Residuals from Electric Utilities;

Proposed Rule

(Docket # EPA

- HQ

- RCRA

- 2009

- 0640
Docket # EPA

- HQ

- RCRA

- 2011

- 0392
Docket # EPA

- HQ

- RCRA

- 2012

- 0028)

Volume 7: Operating Criteria: Endangered species/Surface

water/Inspections/Run

- on Run

- off

December 20142

Background

The U.S. Environmental Protection Agency (Agency or EPA) proposed regulations for

the management of coal combustion residuals (CCRs) which was published in the Federal

Register on June 21, 2010. This proposal, under the Resource Conservation and Recovery Act

(RCRA), addressed the risks from disposal of CCRs generated from the combustion of coal at

electric utilities and from independent power producers. Two regulatory options were proposed.

Under the first option, EPA proposed to reverse its August 1993 Bevill Regulatory and May

2000 Bevill Regulatory Determinations regarding CCR and to list CCRs as special wastes

subject to hazardous waste regulations under subtitle C of RCRA when destined for disposal in

landfill or surface impoundments. Under the seco nd option, EPA proposed to leave the Bevill

determination in place and regulate the disposal of CCR as non

- hazardous solid waste under

subtitle D of RCRA by issuing minimum national criteria. Both options would require

composite liners, groundwater monito ring, structural stability requirements, corrective action,

and closure/post closure care.

EPA also solicited comments on all aspects of both proposed options. The Agency received over

450,000 comments on the proposed rule. The majority of the comments focused on which

regulatory path the Agency should pursue for regulating CCRs, i.e., RCRA’s subtitle C or

subtitle D. EPA also conducted eight public hearings and took additional comments on the

proposed rule. EPA has established three dockets for this regulatory action under Docket ID No.

EPA

- HQ

- RCRA

- 2009

- 0640, Docket ID No. EPA

- HQ

- RCRA

- 2011

- 0392, and Docket ID No.

EPA

- HQ

- RCRA

- 2012

- 0028. All documents in these dockets are available at

http://www.regulations.go v

. Although listed in the index, some information is not publicly

available, e.g., Confidential Business Information (CBI) or other information whose disclosure is

restricted by statute. Certain other material, such as copyrighted material, is not placed on the

Internet and will be publicly available only in hard copy form. Publicly available docket

materials are available either electronically in http://www.regulations.gov or in hard copy at the3

OSWER Docket, E PA/DC, WJC West Building, Room 3334, 1301 Constitution Ave., NW,

Washington, DC. The Public Reading Room is open from 8:30 a.m. to 4:30 p.m., Monday

through Friday, excluding legal holidays. The telephone number for the Public Reading Room is

(202) 566

– 1 744, and the telephone number for the OSWER Docket is 202

– 566

– 0276.

After reviewing all the comments and additional data received, EPA is promulgating a

final rule to regulate the disposal of CCR as solid waste under Subtitle D of RCRA. This rule

address es the risks from structural failures of CCR surface impoundments, groundwater

contamination from the improper management of CCR in landfills and surface impoundments

and fugitive dust emissions.

The Agency has developed seventeen volumes of summarizing comments on major

topics covered in the proposed rule (see table below) and the Agency’s responses to those

comments, as well as a separate volume summarizing comments provided during public

hearings. Since EPA is finalizing a rule under subtitle D of RC RA, only those comments

submitted on the proposed subtitle C rule that are also applicable to the final rule are addressed

in the comment and response documents.

Volume Topic

1 General Comments

2 RCRA Subtitle D Regulatory Approach (Legal issues/Self

- implementing

Design/Reliance on Certifications by an Independent Professional

Engineer/Recordkeeping, State Submissions, Posting to the

Internet/Finance Assurance/Alternative Approaches)

3 Scope and Purpose/Effective Dates/Applicability/Off

- site

Disposal/Definitions

4 Location Restrictions

5 Design Criteria: Liners and Leachate Collection Systems

6 Design Criteria: Structural Integrity

7 Operating Criteria: Endangered species/Surface water/Inspections/Run

- on

Run

- off4

Volume Topic

8 Operating Criteria: Air Criteria

9 Groundwater and Corrective Action

10 Closure and Post

- Closure Care

11 Additional Comments including Overfills/ Harmonization with E LG.

12 Beneficial Use

13 Risk Assessment

14 State Authorities, Programs and Regulations

15 Compendium of Damage Cases

16 Regulatory Impact Analysis (RIA)

17 EPA’s Assessment Program

This volume summarizes comments received on the operating criteria related to

Endangered species, Surface water, Inspections, and Run

- on Run

- off.

Section 4.4.6

- Operating requirements (35203

- 35204) Total Number of Submissions: 4 Total Number of Comments: 4



### Comment Number : EPA

- HQ

- RCRA

- 2009

- 0640

- 06313

- 114 

### Organization 1 

### : Earthjustice et. al. 

### Commenter 1 : Lisa Evans Commenter Type: Advocacy Group
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 4.4.5 

### Comment Excerpt Text:
What prohibitions or performance standards, if any, should be applied to existing landfills?

Performance standards should include the following at a minimum:

• Same siting requirements as proposed landfills,5

• Treatment of wastes to comply with 40 CFR 268.40 as needed,

• Groundwater monitoring,

• Run

- off and run

- on control should be implemented within 6 months of the passage of the rules, and

• Daily cover or dust control operational requirements must be used to meet the applicable air quality

standards.

EPA Response : First, we would note that the Agency was not consistent in discussing the effective date of the RCRA subtitle D rules in the proposal. Specifically, in the regulatory text to proposed 25 7.40(a)(2), the Agency stated that “Except as otherwise specified in this Subpart, 1 all of the requirements in this subpart are applicable [date 180 days after the effective date of the final rule.] On the other hand, in the preamble to the proposed rule under section X (How would the proposed subtitle D regulations be implemented?), the Agency noted that the “RCRA subtitle D alternative, if this alternati ve is ultimately promulgated, would be 180 days after promulgation of a final rule. 75 FR 35210. The date noted in the regulatory text at 257.40(a)(2) is not correct and is inconsistent with RCRA section 4004(c), which provides that rules under 4004(a) become effective six months after publication in the Federal Register. 42 USC 6944(c).

Consistent with 4004(c), EPA will require that CCR landfills install run

- on and run

- off controls

within one year of the effective date of the rule . EPA has determined that this is a sufficient amount of

time to install run

- on and run

- off controls, taking into consideration construction seasons in cold

- weather and high precipitation regions. Also, many of these CCR disposal units should already be subject to run

on and r un

- off controls under the 40 CFR part 257 regulations. However, if final run

- on and run

- off controls can’t be put in place by this timeframe, the record demonstrates that hydrologic and hydraulic measures can be taken in the short term and implemented wi thin 6 months of the date of promulgation of the rule, while long

- term measures are designed and constructed to meet run

- on and run

- off control requirements.

Specifically, in order to meet the timeframes being finalized in today’s rule, CCR landfills ca n implement short

- term measures to manage and prevent the flow of storm water peak discharge, while long

- term, permanent structural and non

- structural measures are taken to meet the run

- on and run

- off controls of the final rule. Typically, these short

- term measures are easily implemented and minimally costly. Short

- term measures may include temporary installation of diversion dikes, straw bales, brush barriers, silt fences, bundles, wattles, or fascines, amongst others. Some examples of long

- term structural controls that can be implemented at CCR landfills include appropriate grading, interceptor ditches, seepage ditches, sedimentation basins, silt traps, check dams, or drainage swales. Long

- term non

structural measures include operation and maintenance proc edures, vegetation control, and routine vigilance. EPA understands that often construction cycles require seasonal scheduling, and so it can take months to implement the long

- term run

- on and run

- off control structures. However, EPA has determined

that sho rt

- term measures can be taken in the interim, while long

- term run

- on and run

- off controls can be permitted, designed, and constructed to meet the requirements of the rule.

1 The run

- on/run

- off controls are not otherwise specified as having a different effective date.6



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06723

- 22 

### Organization 1 

### : West Virginia Departme nt of Environmental Protection (WVDEP) 

### Commenter 1 : Gary Casto on behalf of Randy C. Huffman Commenter Type: State Government
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 4.4.6.2 

### Comment Excerp t Text:
Section 257.81 specifies that CCR landfills and surface impoundments should contain 25 year/24 hour

stormwater runon and runoff controls. Stormwater runon and stormwater runoff controls are not needed at existing or proposed impoundments because th e impoundments are designed to impound and discharge storm events far in excess of a 25 year/24 hour storm event. Stormwater runon controls are appropriate only during and after the closure of surface impoundments. Furthermore, this section states that run off from the active portion of the CCR landfill or surface impoundment must be handled in accordance with

the 257.3

- 3; this section is not included in the proposed regulation.

EPA Response EPA disagrees with the comment asserting that storm water controls are only appropriate during and after closure of CCR surface impoundments. Hydrologic and hydraulic capacity, as determined by an effective design flood control system, is an essential el ement of the overall structural integrity and safety of a CCR surface impoundment. CCR surface impoundments are subject to any number of stresses throughout their operational life; one of the most common causes of a dike or embankment failure being the i nability of the CCR unit to adequately pass or manage flood flows resultant from direct or indirect precipitation. These failures can occur at any point in the CCR unit’s life, not solely during and after closure, and are usually due to inadequate hydrolog ic and hydraulic capacity, leading to internal erosion due to seepage and piping, erosion of spillways, overtopping erosion, and overstressing of the embankment. Furthermore, according to the U.S. Bureau of Reclamation, a common dam failure

mode is due to overtopping, accounting for 30% of the failures in the U.S. over the last 75 years. 2 Overtopping is the direct result of lack of adequate hydrologic and hydraulic capacity of a dam or surface impoundment. Therefore, EPA is not modifying the regulation a s suggested by the

commenter.

Section 3.4.1.3

- Special requirements for stability of CCR SIs and dam integrity (e.g., inspections, design plans, closure plans, annual certification) (35175

- 35176) Total Number of Submissions: 13 Total Number of Comments: 16

2 http://www.usbr.gov/ssle/damsafety/Risk/BestPractices/16

- FloodOvertoppingPP20121126.pdf7



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 01746

- 4 

### Organization 1 

### : LGM Engineers, LLC 

### Commenter 1 : Larry G. Mrazek Commenter Type: Beneficial User
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: the failure of the impoundment containing coal ash was a disaster and caused pollution of the adjacent waterways. However, this should not be the basis for declaring flyash a hazardous waste. More concern should be given to dam safety and the design & construction of impoundments, etc.

EPA Response: EPA has adopted in today’s final rule specific technical criteria intended to ensure adequate dam safety of CCR surface impoundments, throughout the design, construction, operation, maintenance, a nd closure of the CCR unit. Today’s final rule includes design requirements for structural stability and operating requirements for hydraulic and hydrologic capacity, inspection requirements, air criteria, and recordkeeping.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 03028

- 4 

### Organization 1 

### : CS Energy Ltd 

### Commenter 1 : Peter Heeley Commenter Type: Beneficial User
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 4.4.5.2 

### Comment Excerpt Text:

Th e storage of surplus ash in a dam is a geotechnical or structural engineering issue. A risk management approach is essential to ensure the consequences of failure are considered in design
and maintenance of these structures. If dams can fail in a 1st world country (eg Kingston) how much higher risks exist in 3rd world countries where regulation and oversight are far less
controlled.

Clearly Kingston was a disaster which must never be repeated. But this was a system failure caused by inadequate structural engineering. Designation of ash as a hazardous material would not have lessened the engineering risks of a structural failure.

EPA Response: EPA has adopted in today’s final rule specific technical criteria intended to ensure adequate dam safety of CCR su rface impoundments, with specific regard for the structural, geotechnical, and hydraulic and hydrologic engineering adequacy of the CCR unit. Today’s final rule has adopted design and operating requirements which require owners and operators of CCR surface impoundments to insure the dam safety of the CCR unit throughout the unit’s design, construction, operation, and8

maintenance. Today’s final rule includes design requirements for structural stability, including requirements to ensure both the structural an d geotechnical stability of the CCR unit, and operating requirements for hydraulic and hydrologic capacity, inspection requirements, air criteria, and recordkeeping



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 03300

- 2 

### Organization 1 

### : Synthetic Materials, LLC 

### Commenter 1 : Alex Hohne Commenter Type: Beneficial User
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: While the need to properly manage the disposal of these materials is undisputed, it do es not seem reasonable that a mechanical failure of an impoundment would lead to the classification of what have been historically safe materials as hazardous.

EPA Response: EPA has adopted in today’s final rule specific technical criteria intended to ens ure adequate dam safety of CCR surface impoundments, with specific regard for the structural, geotechnical, and hydraulic and hydrologic engineering adequacy of the CCR unit, which EPA reasonably intends to prevent mechanical, or structural, failures. Toda y’s final rule has adopted design and operating requirements which require owners and operators of CCR surface impoundments to insure the dam safety of the CCR unit throughout the unit’s design, construction, operation, and maintenance. Today’s final rule includes design requirements for structural stability, including requirements to ensure both the structural and geotechnical stability of the CCR unit, and operating requirements for hydraulic and hydrologic capacity, inspection requirements, air criteria, and recordkeeping



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 03300

- 5 

### Organization 1 

### : Synthetic Materials, LLC 

### Commenter 1 : Alex Hohne Commenter Type: Beneficial User
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: It would seem more reasonable that the issue of the mechanical failure of the impoundment be addressed rather than the nature of the materials contained therein. While Synmat will not argue that the failure resulted in release of larg e quantities of ash in an uncontrolled manner into the river and the surrounding area, the release does not make what has been historically classified a
non hazardous material hazardous.

EPA Response: EPA has adopted in today’s final rule specific technical criteria intended to ensure adequate dam safety of CCR surface impoundments, with specific regard for the structural, geotechnical, and hydraulic and hydrologic engineering adequacy of the CCR unit, which EPA reasonably intends to9

prevent mechani cal, or structural, failures. Today’s final rule has adopted design and operating requirements which require owners and operators of CCR surface impoundments to insure the dam safety of the CCR unit throughout the unit’s design, construction, operation, an d maintenance. Today’s final rule includes design requirements for structural stability, including requirements to ensure both the structural and geotechnical stability of the CCR unit, and operating requirements for hydraulic and hydrologic capacity, insp ection requirements, air criteria, and recordkeeping.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06313

- 100 

### Organization 1 

### : Earthjustice et. al. 

### Commenter 1 : Lisa Evans Commenter Type: Advocacy Group
Classification: Substantive Comment Category:
Current Task: E xamine Context Assigned/Due:



### Comment Excerpt Text: Plans required for surface impoundments under 265.1303(b), which include the design, construction, and maintenance of existing CCR surface impoundments of a size greater than specified in 265.1303(b)(1) and (2), should already be in the possession of any r esponsible owner or operator. There is no reason to allow for up to 1 year for the submission of such plans. Even if the plans may need to be updated or supplemented, 3 months should be more than adequate to submit such plans, which are essential to protec t people and the environment downstream of the surface impoundment.

EPA Response : Although the commenter is referring to requirements for documentation of design and construction history of the CCR unit proposed under the Subtitle C proposed rule, EPA ha s adopted similar requirements for the documentation of design and construction history under today’s Subtitle D final rule. The final rule requires the owner or operator of CCR units exceeding the specified size threshold to compile and place in the oper ating record design and construction information pertaining to the CCR unit. Among other things, this provision requires the following documentation to be provided by the owner or operator: (1) the name of the owner or operator of the unit; (2) the name o f the unit; and (3) any identification number assigned by the state. In addition, it requires that the owner or operator identify: (4) provide a description of the physical and engineering properties of the foundation and

abutment materials on which the C CR unit is constructed; (5) the location of the CCR unit on a U.S. Geological Survey Map or a topographic map of equivalent scale; (6) provide dimensional drawings of the CCR unit with pertinent engineering structures and appurtenances identified; (7) desc ribe the purpose of the CCR unit; and (8) identify the name and size of the watershed affecting the CCR unit, if any. Detailed information is also required documenting: (9) the design and construction of the unit including dates and descriptions of each zo ne or stage constructed; (10) instrumentation used to monitor the operation of the CCR unit, (11) spillway and diversion design descriptions and construction specifications; (12) provide a description of the physical and engineering properties of the mater ials used in construction each zone or stage of the CCR unit; and (13) provisions for surveillance, maintenance and repair of the CCR unit.10

Through EPA’s CCR Surface Impoundment Assessment effort, EPA identified that a significant number
of CCR surface i mpoundments lacked sufficient design and construction documentation. EPA agrees with the commenter that this information should be made available to the owner or operator of the CCR unit. However, EPA is requiring owners or operators of existing CCR surfac e impoundments to compile this information within one year of the effective date of the rule. EPA notes that some of this information which may not currently be available for the CCR unit, specifically dimensional drawings of the unit, design and construct ion descriptions including each zone or stage of the unit, spillway diversion design descriptions and construction specifications, and descriptions of the physical and engineering properties of the materials which make up the abutments, foundation, and eac h zone of the CCR surface impoundment, may take significant time in coordinating and compiling.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06517

- 18 

### Organization 1 

### : Commenter 1 : Anonymous Commenter Type: Anonymous
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: Also, neither of the regulations concerning inspections, 40 CFR 264.1304 and 40 CFR 265.1304, require owners to develop or submit inspection plans. Please clarify this in the final rulema king.

EPA Response : Although the commenter is referring to requirements for inspections of the CCR unit proposed under the Subtitle C proposed rule, EPA has adopted similar requirements for inspections under today’s Subtitle D final rule. This rule requir es all CCR surface impoundments to be examined by a qualified person at least once every seven days for any appearance of actual or potential structural weakness or other conditions that are disrupting or that have the potential to disrupt the operation or safety of the CCR unit. The results of the inspection by a qualified person must be recorded in the facility’s operating record. Additionally, EPA is requiring the monitoring of all instrumentation supporting the operation of the CCR unit to be conducted by a qualified person no less than once per month. The results of the monitoring of all instrumentation by a qualified person must be recorded in the facility’s operating record. Furthermore, the rule requires owners or operators of any CCR surface impoun dments exceeding the MSHA size threshold (i.e., a height of five feet or more and a storage

volume of 20 acre

- feet or more; or a height of 20 feet or more) to conduct annual inspections of the CCR unit throughout its operating life. The owner or operator o f existing CCR surface impoundments must ensure that the initial annual inspection by a qualified professional engineer is completed and documented with a report no later than three months after the effective date of the rule. The report which the qualifie d professional engineer has documented must be placed in the facility’s operating record and placed on the facility’s publicly accessible internet site. An annual inspection is considered complete when the inspection report has been placed in the facility ’s operating record.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06517

- 26 

### Organization 1 

### :11



### Commenter 1 : Anonymous Commenter Type: Anonymous
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: Also, proper construction of surface impoundments is as important as proper design. Please consider revising this subsection to include a requirement that owners place in the operating record a certification by an independent registered professional engineer tha t all surface impoundment systems and components were constructed in accordance with the design developed under subsection 264.1303(b).

That last part of paragraph 264.1303(e)(17) describes a report that can be included in lieu of the
certification if add itional work is necessary to meet the requirements. However, if this rule stands, it would apply only to new surface impoundments in the design phase, so these issues should have been resolved in the design process. Please consider deleting the last part o f this paragraph that begins with the words “..or, in lieu of the certification...”

EPA Response : EPA agrees with the commenter that proper construction of surface impoundments is as important as proper design. EPA would go further and acknowledge the opera tion and maintenance of the CCR unit is equally important to its design and construction. EPA has adopted requirements that require a periodic structural stability assessment and a periodic safety factor assessment of all CCR surface impoundments exceedin g the size threshold of today’s final rule to ensure that the design, construction, operation, and maintenance of the CCR unit is consistent with recognized and generally accepted good engineering practices. The periodic stability assessment and periodic s afety factor assessment must include certification from a qualified professional engineer stating that the initial assessment of the CCR unit and each subsequent assessment was conducted and meets the requirements of today’s rule. Additionally, these asses sments must comply with the recordkeeping requirements of the final rule, which includes placement in the facility’s operating record.

EPA has revised the language of the final rule that requires all CCR surface impoundments exceeding the
size threshold o f the final rule to conduct periodic structural stability and safety factor assessments, including certification by a qualified professional engineer. EPA has removed the phrase “or, in lieu of the certification...” from today’s final rule



### Comment Number : EPA

- HQ

- RCRA

- 2009

- 0640

- 06517

- 30 

### Organization 1 

### : Commenter 1 : Anonymous Commenter Type: Anonymous
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text:12

40 CFR 264.1304 Inspection requirements for surface impoundments

40 CFR 265.1304 Inspection requirements for surface impoundments

Table 9

– CCR Rule Requirements, on page 35191 of the Federal Register, indicates that surface impoundment owners will have one year from the effective date of the rule to adopt and submit to the EPA a plan for carrying out the surface impoundment inspection requirements of 40 CFR 264 1304 and 40 CFR 265 1304. However, neither of these proposed rules requires an inspection plan. Please clarify this.

EPA Response : Althou gh the commenter is referring to requirements for inspections of the CCR unit proposed under the Subtitle C proposed rule, EPA has adopted similar requirements for inspections under today’s Subtitle D final rule. This rule requires all CCR surface impoundm ents to be examined by a qualified person at least once every seven days for any appearance of actual or potential structural weakness or other conditions that are disrupting or that have the potential to disrupt the operation or safety of the CCR unit. T he results of the inspection by a qualified person must be recorded in the facility’s operating record. Additionally, EPA is requiring the monitoring of all instrumentation supporting the operation of the CCR unit to be conducted by a qualified person no l ess than once per month. The results of the monitoring of all instrumentation by a qualified person must be recorded in the facility’s operating record. Furthermore, the rule requires owners or operators of any CCR surface impoundments exceeding the MSHA s ize threshold (i.e., a height of five feet or more and a storage

volume of 20 acre

- feet or more; or a height of 20 feet or more) to conduct annual inspections of the CCR unit throughout its operating life. The owner or operator of existing CCR surface impo undments must ensure that the initial annual inspection by a qualified professional engineer is completed and documented with a report no later than three months after the effective date of the rule. The report which the qualified professional engineer has documented must be placed in the facility’s operating record and placed on the facility’s publicly accessible internet site. An annual inspection is considered complete when the inspection report has been placed in the facility’s operating record.



### Comm ent Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06869

- 4 

### Organization 1 

### : Commenter 1 : Dalia Patino Echeverri and Varun Kumar Commenter Type: Private Citizen
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 3.7.2 

### Comment Excerpt Text: For these reasons, we believe federal oversight is required for the implementation of preventive

measures

- such as the assessment of structural stability in nearby surface impoundments, or the monitoring of ground water quality.

EPA Response: Regarding the need for federal oversight, t he commenter is referred to the discussion in Unit V of the preamble that discusses the regulatory authority to develop and promulgate the national criteria governing the disposal of CCR in landfills and surface impoundments under subtitle D of RCRA.13

EPA has adopted in today’s final rule specific technical criteria intended to ensure adequate structural stability of CCR surface impoundments, throughout the design, construction, operation, maintenance, and closure of the CCR unit. Today’s final rule includes design requirements for structural stability and operating requirements for hydraulic and hydrologic capacity, inspection requirements, air criteria, and recordkeeping.



### Comment Number: EPA

- HQ

- RC RA

- 2009

- 0640

- 09239

- 45 

### Organization 1 

### : Prairie State Generating Company, LLC (PSGC) 

### Commenter 1 : Keith Bastian Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: Inspection Requirements (40 C.F.R. §§ 264.1304 and 265.1304) These sections should be deleted. The general inspection requirements set forth in Section 264.15 and the contingency plan requirements set forth in Section 264.51 require facilities to

pe rform regular inspections and to develop a plan to minimize hazards to human health and the environment. The existing Subtitle C requirements therefore are sufficiently protective. Theses sections are superfluous and should be deleted. If these sections ar e not deleted, then the requirement to notify the EPA Regional Administrator and the state when the certification is placed in the operating record (40 C.F.R. §§ 264. 1304(a)(5) and 265. 1304(a)(5)) should be deleted. It creates an administrative burden up on both the Regional Administrator and the state without providing any environmental benefit. Having the information available for inspection should be adequate

.

EPA Response : Although the commenter is referring to requirements for inspections of the C CR unit proposed under the Subtitle C proposed rule, EPA has adopted similar requirements for inspections under today’s Subtitle D final rule. This rule requires all CCR surface impoundments to be examined by a qualified person at least once every seven da ys for any appearance of actual or potential structural weakness or other conditions that are disrupting or that have the potential to disrupt the operation or safety of the CCR unit. The results of the inspection by a qualified person must be recorded in the facility’s operating record. Additionally, EPA is requiring the monitoring of all instrumentation supporting the operation of the CCR unit to be conducted by a qualified person no less than once per month. The results of the monitoring of all instrume ntation by a qualified person must be recorded in the facility’s operating record. Furthermore, the rule requires owners or operators of any CCR surface impoundments exceeding the MSHA size threshold (i.e., a height of five feet or more and a storage

volum e of 20 acre

- feet or more; or a height of 20 feet or more) to conduct annual inspections of the CCR unit throughout its operating life. The owner or operator of existing CCR surface impoundments must ensure that the initial annual inspection by a qualified professional engineer is completed and documented with a report no later than three months after the effective date of the rule. The report which the qualified professional engineer has documented must be placed in the facility’s operating record and plac ed on the14

facility’s publicly accessible internet site. An annual inspection is considered complete when the inspection report has been placed in the facility’s operating record.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 09349

- 20 

### Organization 1 

### : Santee Cooper 

### Commenter 1 : Jay Hudson Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 4.4.5.2 

### Comment Excerpt Text: 40 CFR 257.83 (35245) and 40 CFR 264.1304 (352 57) propose inspection requirements for surface impoundments under subtitle D and subtitle C respectively. While the importance of dam safety inspections is generally understood, the proposed inspection requirements are neither appropriate nor adequate.

R eadily accessible and routinely used guidance documents including manuals, guides, reports, and videos such as the widely used Training Aids for Dam Safety (TADS) are available free of charge from FEMA. These resources provide comprehensive descriptions an d guidelines for performing the various types of dam safety inspections used for hydroelectric and water storage dams; and are suitable to develop appropriate and adequate inspection and documentation requirements for surface impoundments. In addition to t he actual physical inspection, these resources provide guidance on properly documenting and reviewing the inspection findings.

The principal classifications for inspections include the following excerpts from the

TADS publication:

• Formal inspections w hich are recurring and "coincide with advancements in the state

- of

- the

- art in design, analysis, and construction that are applicable to the dam under review." A reasonable frequency can be every 5 to 10 years depending on the operation frequency;

• Period ic inspections are performed between formal inspections typically every I to 2 years and

• focus on the current status of the dam and its features;

• Routine inspections provide a continual check on the condition of the dam and are usually performed by o perators or on

- site personnel who are familiar with the dam;

• Special inspections are conducted for particular features or when opportunities allow the inspection of features not normally accessible; and

• Emergency inspections should be performed whene ver the safety of the dam is of concern or15

the occurrence of a significant event such as an earthquake.

EPA is proposing a weekly inspection, without requiring any documentation. In theory, a short inspection interval should increase the chances of findin g an adverse condition. In reality, the judgment of a qualified engineer to establish the frequency and focus as well as the purpose of the dam safety inspection is most effective in detecting and preventing the development of a potentially adverse situati on.

EPA Response: EPA agrees with the commenter that FEMA documentation includes valuable information regarding dam safety design, construction, operation, and maintenance. EPA has largely based dam safety requirements of the final rule on just such guidance. EPA is requiri ng “formal inspections,” including hazard potential assessment, structural stability assessment, and factor of safety assessment, at a frequency of not more than 5 years by a qualified professional engineer for CCR units meeting or exceeding the size thres hold of the final rule in order to mirror the recommendations made by dam safety guidance such as FEMA Federal Guidelines for Dam Safety. Additionally, EPA is requiring annual inspection and records review by a qualified professional engineer of CCR units meeting or exceeding the
size threshold of the final rule.

EPA is also requiring routine inspections, in order to provide an “as

- close

- as

- practicable” a continuous observation of all CCR units, conducted by a qualified person, i.e., weekly inspections. Whi le EPA acknowledges that deferring to the judgment of a qualified professional engineer to establish the frequency and focus, in addition to the purpose, of the dam safety inspection, EPA has chosen to maintain the requirement of all CCR surface impoundmen t owners and operators to conduct at least weekly inspections of the CCR surface impoundment by a qualified person. Several commenters suggested that EPA consider adding regulatory language or preamble discussion to assist owners or operators of CCR

surfac e impoundments in interpreting the specific technical requirements in the regulation. Additionally, EPA identified through the CCR Surface Impoundment Site Assessment effort that the scope and detail of the type of inspection required by the final rule, i. e., informal inspection, is of a nature to provide significant beneficial information and proactive response actions at minimal expense and effort to the owner or operator. EPA observed that a majority of facilities had in place a routine, frequent inspect ion program for all CCR surface impoundments at the facility. Routinely, EPA made recommendations to implement an informal inspection program at facilities that may be lacking such a program. Based on the comments received requesting additional language fo r technical requirements and information garnered from the CCR Surface Impoundment Site Assessment effort, EPA has maintained the requirement that a qualified person conduct weekly inspections of the CCR surface impoundment.



### Comment Number : EPA

- HQ

- R CRA

- 2009

- 0640

- 10239

- 2 

### Organization 1 

### : Lake Wylie Marine Comission 

### Commenter 1 : Ronald H. Wanless Commenter Type: Local Government
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:16

Other Sections: 4.4.5.2 

### Comment Excerpt Text: 3. The fundamental problem we need to address, as a result of the Tennessee impoundment failure, is how do we limit the damage done by impoundment failures. It should be understood that impoundments will always eventually fail.

4. An enginee ring approach for impoundment design that would limit the damage is that of "design to fail gracefully". The following criteria can form the backbone of such an approach.

A. Limit the volume of primary containment ponds to 10 acre feet. If we further limi t the depth
to 10 feet then the surface would need to be an acre or less. This would have the effect of limiting the pressure on the impoundment walls while also reducing the amount of slurry released in a failure. Clearly the 5.4 million cubic yards relea sed in Tennessee was far too much.

B. Surround the array of these smaller ponds with a secondary containment wall.

C. Each of the primary containment ponds should be lined with an impermeable liner to prevent unobserved leaks and progressive damage to t he dyke wall.

D. The array of ponds should be located well away from water courses and separated from all occupied structures by sufficient level fields to dissipate the flow energy of any containment failure. This addresses the damage done to structures by the lahar flow from the breached dyke.

E. Lastly the plants producing the CCRs should be tasked with operating the plant in a manner to maximize the saleability of their CCRs for use in concrete. This will make it possible to
minimize the amount of CCR slurry on site at one time.

EPA Response: EPA disagrees with the suggestion that the Agency finalize a mandatory size limitation for operating CCR surface impoundments. While limiting the volume of CCR surface impoundments to

ten acre

- feet would limit t he volume of CCR released in the event of a structural failure, limiting the size of CCR surface impoundments to 10 acre

- feet may not always be practicable; nor does EPA believe that such a restriction is truly necessary to ensure that the section 4004(a) standard will be met. Many CCR surface impoundments are much larger than ten acre

- feet and have been operating for many years without a structural failure. While EPA acknowledges that this fact in no way guarantees that a failure will not occur, the Agen cy is convinced that the implementation of all of the combined regulatory requirements in this rule (e.g., location criteria, structural integrity, inflow design flood controls and inspection requirements) provides the necessary safeguards that will ensure that CCR surface impoundments are designed, constructed, operated, and maintained to minimize the risks associated with a catastrophic release of impounded CCR due to structural failure. While limiting the size of CCR surface impoundments will reduce ri sks because there will be a lower volume of waste in the unit, the Agency is not convinced that, in practice, such a requirement would meaningfully reduce the risks at many facilities. EPA expects that such a restriction would only cause facilities to con struct either several small units or a

multi

- unit system. Failure of one unit can lead to progressive failure of other units in the system, and thus, ultimately this may not reduce the total volume of waste that could be released into the environment.17



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 10346

- 3 

### Organization 1 

### : Commenter 1 : Edward M. Hull Commenter Type: Private Citizen
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 4.4.5.2 

### Comment Excerpt Text: 3. Thefundamental problem we need to address, as a result ofthe Tennessee impoundment failure, is how do we limit the damage done by impoundment failures. It should be understood that impoundments will always eventually fail. 4. An engineering appro ach for impoundment design that would limit the damage is that of "design to fail gracefully". Thefollowing criteria canform the backbone of such an approach. A. Limit the volume of primary containment ponds to 10 acre feet. Ifwefurther limit the depth to 10 feet then the surface wouldneed to be an acre or less. This would have the effect oflimiting the pressure on the impoundment walls while also reducing the amount ofslurry released in afailure. Clearly the 5.4 million cubic yards released in Tennessee w as far too much. B. Surround the array ofthese smaller pondswith a secondary containment wall. C. Each ofthe primary containment ponds should be lined with an impermeable liner to prevent unobserved leaks. D. Thearray ofpondsshould be located well away fro m water courses and separated from all occupied structures by sufficient level fields to dissipate the flow energy of any containment failure. E. Lastly the plants producing the CCRs should be tasked with operating the plantin a
manner to maximize the sale ablity oftheir CCRs for use in concrete. This will make it possible to minimize the amount of CCR slurry on site at anytime.

Dikes and Dams are barely addressed by either Subtitle C or D. Minimum engineering design standards must be set for all retaining walls and clear Inspection standards must be set. All water that is running off of CCR storage must be controlled and monitored.

EPA Response: EPA disagrees with the suggestion that the Agency finalize a mandatory size limitation for operating CCR surface impoundments. While limiting the volume of CCR surface impoundments to

ten acre

- feet would limit the volume of CCR released in the event of a structural failure, limiting the size of CCR surface impoundments to 10 acre

- feet may not always be practicable ; nor does EPA believe that such a restriction is truly necessary to ensure that the section 4004(a) standard will be met. Many CCR surface impoundments are much larger than ten acre

- feet and have been operating for many years without

a structural failure . While EPA acknowledges that this fact in no way guarantees that a failure will not occur, the Agency is convinced that the implementation of all of the combined regulatory requirements in this rule (e.g., location criteria, structural integrity, inflow design flood controls and inspection requirements) provides the necessary safeguards that will ensure that CCR surface impoundments are designed, constructed, operated, and maintained to minimize the risks associated with a catastrophic release of impound ed CCR due to structural failure. While limiting the size of CCR surface impoundments will reduce risks because there will be a lower volume of waste in the unit, the Agency is18

not convinced that, in practice, such a requirement would meaningfully reduce the risks at many facilities. EPA expects that such a restriction would only cause facilities to construct either several small units or a

multi

- unit system. Failure of one unit can lead to progressive failure of other units in the system, and thus, ulti mately this may not reduce the total volume of waste that could be released into the environment.

EPA has adopted in today’s final rule specific technical criteria intended to ensure adequate dam safety of CCR surface impoundments, throughout the design, construction, operation, maintenance, and closure of the CCR unit. Today’s final rule includes design requirements for structural stability and operating requirements for hydraulic and hydrologic capacity, inspection requirements, air criteria, and
record keeping. Additionally, EPA has adopted requirements in the final rule for run

- on and run

- off from CCR landfills and hydraulic and hydrologic capacity requirements for CCR surface impoundments to ensure the appropriate management of all water which is runni ng off of CCR storage units. This volume of water must be handled in accordance with appropriate regulatory requirements of the Clean Water Act.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 10550

- 4 

### Organization 1 

### : Lake Wylie Marine Commission (LWMC) 

### Commenter 1 : H. S. Hanks Commenter Type: Local Government
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 4.4.5.2 

### Comment Excerpt Text: Dikes and dams are barely addressed by either Subtitle C or D. Minimum e ngineering design standards must be set for all retaining walls and dam inspection standards must be set. All water that is running off of CCR storage must be controlled and monitored.

EPA Response: EPA has adopted in today’s final rule specific technical criteria intended to ensure adequate dam safety of CCR surface impoundments, throughout the design, construction, operation, maintenance, and closure of the CCR unit. Today’s final rule includes design requirements for structural stability and operating r equirements for hydraulic and hydrologic capacity, inspection requirements, air criteria, and recordkeeping.

Section 3.8.2.4

- Inspection requirements Total Number of Submissions: 9 Total Number of Comments: 9



### Comment Number: EPA

- HQ

- RCRA

- 2012

- 0028

- 0059

- 10 

### Organization 1 

### : Commonwealth of Kentucky 

### Commenter 1 : Anthony Hatton Commenter Type: State Government
Classification: NODA2 Substantive Comment Category:
Current Task: Examine Context Assigned/Due:19



### Comment Excerpt Text:

The Com monwealth believes, from years of solid waste permitting experience, that a site designed by a professional engineer includes unit dewatering and sufficient stability making weekly unnecessary. The Commonwealth believes that annual inspections should be su fficient

EPA Response: EPA disagrees with the commenter that unit dewatering and sufficient stability make weekly inspections unnecessary. The final rule requires weekly inspections to be conducted for all CCR surface impoundments. Periodic inspections of all CCR units are a

n ecessary practice to ensure that the overall structural integrity of the CCR unit is maintained and that actual and potential structural weaknesses and other hazardous conditions are quickly identified and remediated throughout the active life of the unit. All CCR surface impoundments pose some risk of release

— whether from a catastrophic failure or from a more limited structural failure, such as occurred at Duke Energy’s Dan River plant. Periodic inspections are a generally accepted, prudent engineering pr actice that will significantly reduce the risks of such failures; during the Impoundment Assessment Program, EPA discovered that many facilities routinely conduct some sort of periodic inspection and monitoring, although the frequency varied widely

between facilities. The final rule merely codifies this practice, by establishing a consistent minimum. EPA is therefore requiring that all CCR surface impoundments be inspected by a qualified person weekly (for visual signs of a potentially adverse condition). Consistent with the proposed rule, EPA is also requiring annual inspections for all CCR surface impoundments that exceed the specified size threshold of: (1) a height of five feet and a storage capacity of 20 acre

feet; or (2) a height of 20 feet, must als o be inspected no less than annually by a qualified professional engineer. These inspection requirements are generally being promulgated as proposed, with minor technical clarifications.

EPA has concluded, consistent with FEMA guidelines, that routine i nspections of all CCR units are necessary to ensure that the units are safely operated and that issues that could disrupt the safety and continuing operation of these units are promptly identified and remediated. Accordingly, the final rule requires weekl y inspections to be conducted at all CCR surface impoundments to confirm that they are operating safely. These inspections must be conducted by a qualified person trained to recognize specific signs of structural instability and other

hazardous conditions by visual observation and if, applicable monitor instrumentation.



### Comment Number: EPA

- HQ

- RCRA

- 2012

- 0028

- 0109

- 6 

### Organization 1 

### : Hoosier Energy Rural Electric Cooperative, Inc. (Hoosier)


### Commenter 1 : Michalene Reilly Commenter Type: Electric Utility Company
Classification: NODA2 Substantive Comment Category:
Current Task: Examine Context Assigned/Due:20



### Comment Excerpt Text: On structural integrity, weekly inspections are more than should be required for any facility, although we ag ree that unusual weather or seismic conditions should trigger immediate inspections. Hoosier believes that inspection requirements are site specific and can be made part of any permit, with a minimum annual requirement.

EPA Response: The final rule requir es weekly inspections to be conducted for all CCR surface impoundments. Periodic inspections of all CCR units are a necessary practice to ensure that the overall structural integrity of the CCR unit is maintained and that actual and potential structural

w eaknesses and other hazardous conditions are quickly identified and remediated throughout the active life of the unit. All CCR surface impoundments pose some risk of release

— whether from a catastrophic failure or from a more limited structural failure, suc h as occurred at Duke Energy’s Dan River plant. Periodic inspections are a generally accepted, prudent engineering practice that will significantly reduce the risks of such failures; during the Impoundment Assessment Program, EPA discovered that many faci lities routinely conduct some sort of periodic inspection and monitoring, although the frequency varied widely between facilities. The final rule merely codifies this practice, by establishing a consistent minimum. EPA is therefore requiring that all CCR surface impoundments be inspected by a qualified person weekly (for visual signs of a potentially adverse condition). Consistent with the proposed rule, EPA is also requiring annual inspections for all CCR surface impoundments that exceed the specified siz e threshold of: (1) a height of five feet and a storage capacity of 20 acre

- feet; or (2) a height of 20 feet, must also be inspected no less than annually by a qualified professional engineer. These inspection requirements are generally being promulgated as proposed, with

minor technical clarifications.

EPA has concluded, consistent with FEMA guidelines, that routine inspections of all CCR units are necessary to ensure that the units are safely operated and that issues that could disrupt the safety and c ontinuing operation of these units are promptly identified and remediated. Accordingly, the final rule requires weekly inspections to be conducted at all CCR surface impoundments to confirm that they are operating safely. These inspections must be conduc ted by a qualified person trained to recognize specific signs of structural instability and other hazardous conditions by visual observation and if, applicable monitor instrumentation.

Section 4.4.5.2

- Stability requirements for CCR SI and dam integri ty, including design certification by independent PE, weekly inspections, annual re

- certification (35203) Total Number of Submissions: 23 Total Number of Comments: 29



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 05906

- 2 

### Organization 1 

### : Associated Electric Cooperative, Inc. (AECI) 

### Commenter 1 : Brent Ross Commenter Type: Electric Utility Company21

Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 4.1.1 

### Comment Excerpt Text: AECI recognizes the magnitude of the TVA ash spill of 2008 and that this spill was a result of poor engineering and inspection practices that resulted from poor dam safety oversight. AECI agrees that any development of federal regulation for coal CCRs should be under RCRA Subtitle
D no n

- hazardous waste rules and should include impoundment stability criteria.

EPA Response: EPA has adopted in today’s final rule specific technical criteria intended to ensure adequate dam safety of CCR surface impoundments, with specific regard for the str uctural, geotechnical, and hydraulic and hydrologic engineering adequacy of the CCR unit under RCRA Subtitle D. Today’s final rule has adopted design and operating requirements which require owners and operators of CCR surface impoundments to insure the da m safety of the CCR unit throughout the unit’s design, construction, operation, and maintenance. Today’s final rule includes design requirements for structural stability, including requirements to ensure both the structural and geotechnical stability of th e CCR unit, and operating requirements for hydraulic and hydrologic capacity, inspection requirements, air criteria, and recordkeeping



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06198

- 12 

### Organization 1 

### : Ameren Corporation 

### Commenter 1 : Paul R. Pike
Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: In addition to the above, Ameren believes that the requirement to monitor instrumentation once every seven day s under proposed 40 C.F.R. § 257.83(a)(2) (75 Fed. Reg. at 35245) is excessive. A weekly instrumentation inspection obligation is clearly unwarranted for all dams. Even the FEMA Federal Guidelines for Dam Safety do not contemplate a monitoring frequency of this magnitude, suggesting that the frequency of instrumentation monitoring "may be reduced after the project has been in operation for an extended time and performance observation data indicates that readings have stabilized." The FEMA guidelines appropr iately recognize that there
is not a one

- size

- fits

- all monitoring frequency for instrumentation, but rather that such an obligation should be tailored to reflect the stage of the dam (e.g., construction, first filling, long

term), its function, and its haz ard rating. Therefore, we recommend that EPA amend this condition to require equipment inspections once a month for dams with a dam hazard potential rating of "high" and quarterly for impoundments with a dam hazard potential rating of "significant."

EPA Response: EPA agrees with commenters that it is unnecessary and impractical to require weekly monitoring of instrumentation at CCR surface impoundments. EPA acknowledges the number and variety22

of monitoring and instrumentation present at CCR surface i mpoundments is significant and that weekly monitoring of instrumentation is excessive. EPA has modified language in the final rule to require that instrumentation at CCR surface impoundments be monitored and recorded at an interval not to exceed

one month.

EPA believes it important to conduct frequent, consistent monitoring of existing and new CCR surface impoundments to help identify and prevent potentially harmful conditions from developing, as well as create a body of data that can be used to assess the long

- term performance of the structure. As we have stated previously, EPA has determined that all CCR surface impoundments must be subject to some form of inspection and monitoring. EPA recognizes that CCR surface impoundments are often subject to

build

- o ut, and the size of these impoundments may increase as the demands for capacity from the facility grow. Because it is essential to establish an operating record of CCR surface impoundments, EPA has concluded that monitoring of instrumentation must be under taken for all CCR surface impoundments, not simply those of Significant and High Hazard Potential Classifications. EPA has also determined that it would be advantageous to require specific inspection and monitoring requirements to document an operating hi story prior to expansion.

EPA does, however, agree with the commenter that a requirement to monitor instrumentation once every seven days is excessive because of the number and variety of instrumentation that may be present at the CCR surface impoundment and the commonly gradual changes that occur over time in the readings of most instrumentation. EPA acknowledges that in the case of most instrumentation, weekly instrumentation monitoring is unlikely to indicate significant, detectable changes to readings . EPA acknowledges that the monthly time frame is more likely to be an appropriate interval for monitoring of instrumentation given the nature of instrumentation present at CCR surface impoundments. Therefore, EPA has changed the monitoring instrumentation requirements for all CCR surface impoundments to a frequency of not more than 30 days and immediately following unusual events, such as large floods, earthquakes, suspected sabotage, and vandalism. EPA has determined, based partly on FEMA Federal

Guidelin es for Dam Safety and EPA’s CCR Dam Assessment effort that scheduled monitoring of instrumentation is more practical on a monthly basis. Additionally, EPA believes that conservative practices warrant the monitoring of instrumentation following unusual even ts which may induce abnormal or unanticipated stresses on the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06298

- 30 

### Organization 1 

### : Tennessee Department of Environment and Conservation (TDEC) 

### Commenter 1 : Paul L. Sloan Commenter Type: State Government
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 4.4.5.1 4.4.7.4 4.4.8.2 4.4.9.1 

### Comment Excerpt Text: Surface impoundments receiving CCR for treatment or disposal should be regu lated from initial design through completion of post

- closure monitoring requirements. For existing CCR surface impoundments there should be two categories; (1) CCR waste surface impoundments to be used23

for no more than five additional years from the eff ective date of the Final EPA CCR Rule, and (2) CCR surface impoundments that will be used five years after the effective date of the EPA
CCR Final Rule.

(1) Regulations for existing CCR surface impoundments to be closed within five years of the
effective date of the Final EPA CCR Rule should include structural analysis with repair/improvements required to meet a dam safety factor of 1.2. Additional requirements should include inspections quarterly, installation of groundwater monitoring wells, semiannual

g roundwater monitoring, closure plan, post

- closure monitoring and maintenance and financial assurance in an amount sufficient to cap the surface impoundment and to perform environmental investigation and cleanup should the surface impoundment fail or have r eleases to groundwater and surface water. The CCR surface impoundment owner should be required to submit a statement committing to closure of the surface impoundment within five years and acknowledge the responsibility to comply with (2) below should the s urface impoundment not be closed on
schedule.

(2) Regulations for existing CCR surface impoundments to be operated for more than five years after the effective date of the Final EPA CCR Rule should include a structural analysis with repair/improvements re quired to meet a dam safety factor of 1.5. These surface impoundments should be retrofitted with a synthetic liner to prevent failure migration of CCR contaminants into ground water. The CCR surface impoundment owner should be required to obtain a solid wa ste processing/disposal permit following the RCRA Subtitle D public participation process. Additional recommended requirements are quarterly inspections, installation of groundwater monitoring wells, semi

- annual groundwater sampling, annual estimation of r emaining life, closure plan with cap, post

- closure monitoring and maintenance plan and financial assurance sufficient to perform environmental investigation and clean up should the surface impoundment fail or release contaminants to groundwater or surface water.

EPA Response: EPA agrees with the commenter that there should be specific factors of safety which CCR surface impoundments must meet. EPA has adopted, in a departure from the proposed rule, specific factors of safety which must be met or exceeded b y the dike of the CCR surface impoundment. These factors of safety for existing CCR surface impoundments are: : (1) a static factor of safety under the long

term, maximum storage pool loading condition equal to or exceeding 1.50; (2) a static factor of saf ety under the maximum surcharge pool loading condition equal to or exceeding 1.40; (3) a calculated seismic factor of safety equal to or exceeding 1.00; and for units that are constructed of soils which are susceptible to liquefaction, (4) a liquefaction f actor of safety equal to or exceeding 1.20. The factors of safety for new CCR surface impoundments are: (1) the calculated static factor of safety under the long

term, maximum storage pool loading condition equaling or exceeding 1.50; (2) the calculated st atic factor of safety under the maximum surcharge pool loading condition equaling or exceeding 1.40; (3) the calculated static factor of safety under the end

- of

- construction loading condition equaling or exceeding 1.30; (4) the calculated seismic factor of safety equally or exceeding 1.00 and; for units that are constructed of soils which are susceptible to liquefaction, (5) a liquefaction factor of safety equal to or exceeding 1.20. EPA has adopted these factors of safety from a combination of guidance, i ncluding US Army Corps of Engineers Engineer Manual EM 1110

- 2

- 1902“Slope Stability” (October 2003), and EM
1110

- 2

- 1902 “Stability of Earth and Rock

- Fill Dams” and FEMA Federal Guidelines for Dam Safety : Earthquake Analysis and Design of Dams.24

Additionally, consistent with FEMA Federal Guidelines for Dam Safety, today’s final rule requires a range of inspections and assessments from weekly to annual to quinquennial. The requirements of the final rule require that these inspections and assessmen ts vary in the scope and detail of the inspection or assessment and with who is qualified to conduct the inspection or assessment. Today’s final rule requires that all CCR surface impoundments be inspected by a qualified person at intervals not exceeding 7 days for any appearances of actual or potential structural weakness and other conditions which are disrupting or have the potential to disrupt the operation or safety of the CCR unit. Additionally, at intervals not exceeding 7 days, all CCR surface impoun dments must be inspected to ensure that all outlets of hydraulic structures which pass beneath the base of the surface impoundment or through the dike of the CCR unit are free from abnormal discoloration, flow or discharge of debris or sediment. All CCR su rface impoundments in excess of the size threshold of today’s final rule must be inspected annually by a qualified professional engineer to identify signs of distress or malfunction of the CCR unit and appurtenant structures, all hydraulic structures under lying the base of the CCR unit or passing through the dike of the CCR unit for structural integrity and continued safe and reliable operation, and must review all available information regarding the status and condition of the CCR unit. Finally, all CCR su rface impoundments in excess of the size threshold of today’s final rule must undergo a formal assessment at an interval not to exceed 5 years by a qualified professional engineer. This formal assessment must include a structural stability assessment, a ha zard potential assessment, and a safety factor assessment.

EPA has modified today’s rule language from the proposal to require documentation of the weekly and special inspections. EPA is requiring that the results of the inspection by a qualified person m ust be recorded in the facility’s operating record. These recorded results of weekly and special inspections must additionally be reviewed by the qualified professional engineer during the annual inspection and the periodic structural stability assessment for CCR surface impoundments which are subject to those requirements, i.e., units which meet or exceed the size threshold of today’s final rule.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06298

- 31 

### Organization 1 

### : Tennessee Department of Environment and Conserva tion (TDEC) 

### Commenter 1 : Paul L. Sloan Commenter Type: State Government
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 4.4.4.1 4.4.5.1 4.4.7.1 4.4.8.2 4.4.9.1 

### Comment Excerpt Text:

New CCR surface impoundments should be permitted following the EPA Subtitle D criteria for solid waste landfills. The regulations should include:

- Public Notice of intent to construct.

- Demonstration of suitable geologic conditions for construction.

- An engineerin g design which includes a geologic buffer, synthetic liner, leachate collection system, groundwater monitoring system with a minimum of four wells, buffer zones, construction with a dam safety factor of 1.5, estimated disposal capacity of the surface impou ndment, seismic analysis and seismic safety factor of 1.5, closure plan, post

- closure monitoring and maintenance plan and financial assurance in an amount sufficient to complete environmental investigation and cleanup should the surface impoundment fail or have releases to groundwater and/or surface water.

- The initial plans should indicate whether the surface impoundment will be used for CCR25

treatment or for waste treatment and CCR disposal.

EPA Response: EPA agrees with the commenter that there should be specific factors of safety which CCR surface impoundments must meet. EPA has adopted, in a departure from the proposed rule, specific factors of safety which must be met or exceeded by the dike of the CCR surface impoundment. These factors of safety for e xisting CCR surface impoundments are: : (1) a static factor of safety under the long

term, maximum storage pool loading condition equal to or exceeding 1.50; (2) a static factor of safety under the maximum surcharge pool loading condition equal to or excee ding 1.40; (3) a calculated seismic factor of safety equal to or exceeding 1.00; and for units that contain soils which are susceptible to liquefaction, (4) a liquefaction factor of safety equal to or exceeding 1.20. The factors of safety for new
CCR surfa ce impoundments are: (1) the calculated static factor of safety under the long

- term, maximum storage pool loading condition equaling or exceeding 1.50; (2) the calculated static factor of safety under the maximum surcharge pool loading condition equaling o r exceeding 1.40; (3) the calculated static factor of safety under the end

- of

- construction loading condition equaling or exceeding 1.30; (4) the calculated seismic factor of safety equally or exceeding 1.00 and; for units that are constructed of soils whi ch are susceptible to liquefaction, (5) a liquefaction factor of safety equal to or exceeding 1.20. EPA has adopted these factors of safety from a combination of guidance, including US Army Corps of Engineers Engineer
Manual EM 1110

- 2

- 1902“Slope Stability” (October 2003), and EM 1110

- 2

- 1902 “Stability of Earth and
Rock

- Fill Dams” and FEMA Federal Guidelines for Dam Safety : Earthquake Analysis and Design of

Dams.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06398

- 104 

### Organization 1 

### : Duke Energy 

### Commenter 1 : Mike Stroben Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: Duke Energy supports the development of appropriate structural integrity standards for CCR

s urface impoundments.

EPA Response: EPA has adopted in today’s final rule specific structural stability requirements intended to ensure adequate dam safety of CCR surface impoundments, throughout the design, construction, operation, maintenance, and closur e of the CCR unit. Today’s final rule includes design requirements for structural stability and operating requirements for hydraulic and hydrologic capacity, inspection requirements, air criteria, and recordkeeping.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 0 6398

- 62 

### Organization 1 

### : Duke Energy


### Commenter 1 : Mike Stroben Commenter Type: Electric Utility Company
Classification: Substantive26

Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: Duke Energy also believes that the requirement to perform inspections and monitor instrumentation once every seven days under proposed 40 C.F.R. § 257.83(a)(2) is excessive for most dams. Clearly, there are times when frequent (weekly) inspections and instrumentation monitoring is advisable (such as during initial filling of an impoundment). However, as a general requirement throughout the life of an impoundment, it is unnecessary. Instead, Duke Energy favors a general required inspection and equipment inspection frequency of once a month fo r dams with a dam hazard potential rating of “high” and quarterly for impoundments with a dam hazard potential rating of “significant.” The rule should also provide that the general required equipment inspection frequency should be variable based on site

- s pecific conditions and upon the recommendation of an independent professional engineer.

Duke Energy agrees with the proposed language in 40 C.F.R. § 257.83(e), which provides that the “qualified person” performing periodic inspections be “trained to recog nize specific signs of structural instability and other hazardous conditions by visual observation.” This allows for those who will be performing inspections to have training which is specific to the facility they are inspecting, as well as the frequency a nd thoroughness of the inspections they will be performing. For example, an individual performing a routine monthly inspection would not require the depth of education, experience, and training that an individual performing an annual inspection would requi re.

EPA Response: The final rule requires weekly general inspections and monthly instrumentation inspections to be conducted for all CCR surface impoundments. Periodic inspections of all CCR units are a necessary practice to ensure that the overall struc tural integrity of the CCR unit is maintained and that actual and potential structural weaknesses and other hazardous conditions are quickly identified and remediated throughout the active life of the unit. All CCR surface impoundments pose some risk of re lease

— whether from a catastrophic failure or from a more limited structural failure, such as occurred at Duke Energy’s Dan River plant. Periodic inspections are a generally accepted, prudent engineering practice that will significantly reduce

the risks of such failures; during the Impoundment Assessment Program, EPA discovered that many facilities routinely conduct some sort of periodic inspection and monitoring, although the frequency varied widely between facilities. The final rule merely codifies this practice, by establishing a consistent minimum. EPA is therefore requiring that all CCR surface impoundments be inspected by a qualified person both weekly (for visual signs of a potentially adverse condition) and monthly (for instrumentation monitoring). Consistent with the proposed rule, EPA is also requiring annual inspections for all CCR surface impoundments that exceed the specified size threshold of: (1) a height of five feet and a storage capacity of 20 acre

- feet; or (2) a height of 20 feet, must als o be inspected no less than annually by a qualified professional engineer. These inspection requirements are generally being promulgated as proposed, with

minor technical clarifications.27

The final inspection requirements have been drawn heavily from gui delines established by FEMA for dam safety, under which maintaining structural integrity involves continuous evaluation of the unit, based on periodic inspections. To be most effective, FEMA suggests, and EPA concurs, that inspections be varied with respe ct to both the time interval between inspections and the level of detail of the inspection. FEMA guidance, in part, suggests that inspections can be categorized as either: visual observations to identify abnormal conditions (i.e., informal inspections); f

ield inspections by a professional engineer (i.e., intermediate inspections); and a technical review to determine if the unit meets current and accepted design criteria and practices (i.e., formal inspection). 3 In general, FEMA recommends that inspection s focusing on visual observations should be conducted often (e.g., weekly) while more substantive technical evaluation should be conducted every year to every five years depending on the engineering analyses required. (See also the preamble discussion on t he requirements specified in §§ 257.73 and 257.74 of this rule, in particular the discussion addressing the five year time interval for structural stability and factor of safety reassessments.)

For the reasons discussed above, EPA has concluded, consist ent with FEMA guidelines, that routine inspections of all CCR units are necessary to ensure that the units are safely operated and that issues that could disrupt the safety and continuing operation of these units are promptly

identified and remediated. Ac cordingly, the final rule requires both weekly inspections and monthly instrumentation inspections to be conducted at all CCR surface impoundments to confirm that they are operating safely. These inspections must be conducted by a qualified person trained to recognize specific signs of structural instability and other hazardous conditions by visual observation and if, applicable monitor instrumentation. EPA is also retaining the annual inspection requirement for CCR surface impoundments exceeding the spec ified size threshold established in this rule. This inspection must be conducted and certified by a qualified professional engineer. Units exceeding this size threshold pose a higher degree of risk of release of CCRs to the environment than other types o f CCR surface impoundments (e.g., incised or “small” CCR units) and as such warrant additional regulatory control and oversight.

In a departure from the proposed rule, EPA is requiring the monitoring of all instrumentation supporting the operation of the CCR unit to be conducted by a qualified person no less than once per month. This is a change from the proposal which required instrumentation to be monitored no less than every seven days.

In considering the frequency of monitoring of instrumentation, the Agency was influenced by a number of factors including the FEMA guidelines suggested by the commenters, in addition to FERC guidance. FEMA guidance identifies that instrumentation monitoring frequency must be established “in order to give a timely warn ing of possible adverse conditions. Furthermore, FERC hydropower dam guidance, details that, for high

- and significant hazard potential dams, the types of monitoring instrumentation which EPA observed most frequently at CCR surface impoundments during the Assessment Effort, i.e., reservoir level devices, drain flow devices,

3 See “ Federal Guidelines for Dam Safety ” Federal Emergency Management Agency

. (Reprinted April

2004).28

seepage/leakage flow devices, should be monitored at a frequency of not more than “monthly to quarterly.” Given the nature of the material in CCR units, EPA has taken a conservative

appr oach in requiring that instrumentation monitoring be conducted monthly for all CCR surface impoundments, including low hazard potential CCR surface impoundments in addition to high

and significant hazard potential CCR surface impoundments. 4 Also weighing heavily in EPA’s decision were the observations made as part of the Assessment Program, which revealed that many CCR units are equipped with only “basic” measuring devices such as piezometers and pool

elevation and freeboard instrumentation and not the mo re sophisticated (i.e., sensitive) measuring devices for measuring p ressure, seepage, internal movement, slope movement; and vibration. These findings strongly suggested to the Agency that, given the status of current instrumentation employed at CCR facilities, weekly monitoring would be excessive, impractical, and

— of greatest significance

-- unlikely to indicate any measurable changes in structural stability in such a short time frame. EPA, therefore, agrees that a monthly time frame is a more appropr iate interval for detecting discernible or significant changes in the operation of the CCR unit. EPA has not, however, differentiated between high, significant, and low hazard potential CCR surface impoundments in the requirement that instrumentation be mo nitored monthly, as commenters suggested. Through the Assessment effort, EPA identified that typically low hazard potential CCR surface impoundments were monitored less frequently than high

- or significant hazard potential CCR surface impoundments by the o wner or operator. Additionally, these low hazard potential CCR surface impoundments less commonly were equipped with sophisticated monitoring instrumentation, including remote monitoring instrumentation which would allow the owner or operator to monitor th e unit from a remote location. Based on these observations, along with the limited burden that instrumentation monitoring places on the owner or operator, the rule requires all CCR surface impoundments with instrumentation to be monitored monthly.



### Commen t Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06398

- 7 

### Organization 1 

### : Duke Energy 

### Commenter 1 : Mike Stroben Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 5.6.4 

### Comment E xcerpt Text: Duke Energy also supports the development of structural integrity standards for CCR surface impoundments. Since the ash release at the Tennessee Valley Authority’s Kingston Fossil Fuel Plant in December of 2008, EPA has been conducting compreh ensive structural integrity assessments of the CCR surface impoundments at many coal

- fired electric generating facilities across the country, including Duke Energy facilities. None of the inspections at Duke Energy facilities has resulted in any of the imp oundments receiving an “unsatisfactory” rating, meaning

4 https://www.ferc.gov/industries/hydropower/safety/guidelines/e ng

- guide/chap9.pdf29

that not a single impoundment is considered unsafe or requires immediate or emergency
remedial action.

EPA Response: EPA has adopted in today’s final rule specific structural stability requirements intended to ensure adequate dam safety of CCR surface impoundments, throughout the design, construction, operation, maintenance, and closure of the CCR unit. Today’s final rule includes design requirements for structural stability and operating requirement s for hydraulic and hydrologic capacity, inspection requirements, air criteria, and recordkeeping.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06844

- 2 

### Organization 1 

### : Intermountain Power Agency (IPA) 

### Commenter 1 : James A. Hewlett Commenter Type: Electric Utilit y Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 8.6 

### Comment Excerpt Text:

Evaluation of Potential Risks

In the preamble to the proposed rules, the EPA stated that part of the decision to revisit its regulatory determination for CCR under the Bevill amendment was driven by the failure of a surface impoundment at Tennessee Valley Authority (TVA) Kingston fossi l plant in December 2009 and by the revision of risk assessment methodology based on new information. As a result of these revisions, the EPA co

- proposed regulations of the CCR under RCRA Subtitle C.

At the TVA Kingston plant, the release of 5.4 million cubic yards of coal ash (mixed with 327 million gallons of water) covered about 300 acres of land surface and water bodies. Due to the potential harm to the environment, the utility, local and federal environmental agencies immediately began sampling and a nalysis of the ash itself, surface water, groundwater, drinking water, and air. The Tennessee Department of Health reviewed all analytical results to ensure that public health was protected.

On September 7,2010, the Tennessee Department of Health release d the Final Report of Public Health Assessment which was prepared under a cooperative agreement with the U.S. Department of Health and Human Services Agency for Toxic Substances and Disease Registry.

The report found minimal health risks from the coal as h spill at TVA's Kingston facility and noted that the significant risk is the safety risk of engulfment by the ash to people in the path of the ash release. It appears that it was not the "toxicity" or the environmental "hazard" of CCR specific waste found in that impoundment that caused the ecological disaster, but the sheer size of the release. The ecological damage would have been severe even if the material released was simply mud.30

Potential risks from CCR, including dam safety, can be properly address ed by federal nonhazardous and equally protective Subtitle D regulations. Previously, EPA has agreed that hazardous waste regulation will result in unnecessary regulation. In its final Regulatory . Determination issued on May 22,2000, EPA concluded that ha zardous waste regulation was not warranted for coal ash. The Agency found that the inflexible nature of the federal hazardous waste program would result in excess costs and unduly burdensome regulations for coal ash. Most recently, EPA has found that the c oal ash being recovered from the Kingston release site can be safely disposed of in a RCRA Subtitle D non

- hazardous waste facility. Rather than regulating coal ash under Subtitle C, the EPA should work with other federal and state agencies by focusing on d eveloping dam integrity programs to enhance surface impoundment safety.

EPA Response: EPA has adopted in today’s final rule specific technical criteria intended to ensure adequate dam safety of CCR surface impoundments, throughout the design, construction , operation, maintenance, and closure of the CCR unit under RCRA Subtitle D standards. Today’s final rule includes design requirements for structural stability and operating requirements for hydraulic and hydrologic capacity, inspection requirements, air c riteria, and recordkeeping. EPA has based the structural stability requirements of the final rule on a number of dam safety programs and guidance, including that of FEMA, USACE, and MSHA.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06987

- 11 

### Organization 1 

### : Entergy Services, Inc. 

### Commenter 1 : Joseph Hantz Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 7.1.2 

### Comment Excerpt Text: Furthermore, Entergy believes that the intent of EPA’s proposed regulation of CCRs, to ensure protection of human health and the environment, can be adequately achieved through Subtitle D by issuing national minimum criteria and establishing dam and impoundment safety requirements to a ddress the structural integrity of surface impoundments to prevent catastrophic releases, and that Arkansas and Louisiana’s existing regulations are a testimony to the ability of state programs to do so.

EPA Response: EPA has adopted in today’s final rule specific technical criteria intended to ensure adequate dam safety of CCR surface impoundments, throughout the design, construction, operation, maintenance, and closure of the CCR unit under RCRA Subtitle D standards. Today’s final rule includes design re quirements for structural stability and operating requirements for hydraulic and hydrologic capacity, inspection requirements, air criteria, and recordkeeping.31



### Comment Number : EPA

- HQ

- RCRA

- 2009

- 0640

- 07534

- 18 

### Organization 1 

### : Aquaterra Environmental Solutions, Inc. 

### Commenter 1 : Scott Waltrip Commenter Type: Other Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 3.4.1.4 

### Comment Excerpt Text: Parts 264 and 265 Depth and volume thresholds

Parts 264 and 265 give several regulatory requirements that hinge on the depth and volume limitations of subsections 264.1303(b) and 265.1303(b) for surface impoundments. They are:

§§264.1303 and 265.1303 R equire design plans for surface impoundments exceeding the
limitations

§§265.1304 and 265.1304 Require weekly inspections for surface impoundments exceeding the limitations; the subsections also require annual P.E. inspection/certification

§§265.1305 a nd 265.1305 Require approved closure plans for surface impoundments exceeding
the limitations

We have addressed design plans elsewhere in our comments. However, please clarify whether owners of smaller impoundments have to meet the closure requirements, or whether they simply do not have to submit closure plans for approval. Also, please clarify whether owners of smaller impoundments have to inspect the facilities at all, or whether they may inspect at some other
intervals.

EPA Response: Although the co mmenter is referring to requirements for inspections of the CCR unit proposed under the Subtitle C proposed rule, EPA has adopted similar requirements for inspections under today’s Subtitle D final rule. This rule requires all CCR surface impoundments to b e examined by a qualified person at least once every seven days for any appearance of actual or potential structural weakness or other conditions that are disrupting or that have the potential to disrupt the operation or safety of the CCR unit. The result s of the inspection by a qualified person must be recorded in the facility’s operating record. Additionally, EPA is requiring the monitoring of all instrumentation supporting the operation of the CCR unit to be conducted by a qualified person no less than once per month. The results of the monitoring of all instrumentation by a qualified person must be recorded in the facility’s operating record. Furthermore, the rule requires owners or operators of any CCR surface impoundments exceeding the MSHA size thres hold (i.e., a height of five feet or more and a storage
volume of 20 acre

- feet or more; or a height of 20 feet or more) to conduct annual inspections of the CCR unit throughout its operating life. The owner or operator of existing CCR surface impoundments must ensure that the initial annual inspection by a qualified professional engineer is completed and documented with a report no later than three months after the effective date of the rule. The report which the qualified professional engineer has document ed must be placed in the facility’s operating record and placed on the facility’s publicly accessible internet site. An annual inspection is considered complete when the inspection report has been placed in the facility’s operating record. Units which do not meet or exceed the32

size threshold of today’s final rule are not required to be inspected annually or assessed quiquennially by a qualified professional engineer. The owner or operator of all CCR surface impoundments, regardless of size, must comply wit h the hazard potential assessment requirements, hydrologic and hydraulic capacity requirements, and the weekly inspection requirements.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 08218

- 30 

### Organization 1 

### : Maryland Department of the Environment (MDE) 

### Commenter 1 : Shari T. Wilson Commenter Type: State Government
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 5.6 

### Comment Excerpt Text: Maryland does not have experience with wet

- ash impoundments, as there are currently none in Maryland. However, as there are impoundments adjacent to Maryland waters, Maryland supports EPA’s effort to insure the safety of these structures.

EPA Response: EPA has adopted in today’s final rule speci fic technical criteria intended to ensure adequate dam safety of CCR surface impoundments, throughout the design, construction, operation, maintenance, and closure of the CCR unit under RCRA Subtitle D standards. Today’s final rule includes design requirem ents for structural stability and operating requirements for hydraulic and hydrologic capacity, inspection requirements, air criteria, and recordkeeping.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 08787

- 43 

### Organization 1 

### : Association of State and Territorial Solid Waste Management Officials (ASTSWMO) 

### Commenter 1 : Stephen A. Cobb (Al) Commenter Type: State Government
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 3.4.1.3.2 3.4.1.3.1 

### Comment Excerpt Text: ASTSWMO notes that the NPDES permit program appropriately focuses on effluent discharge limits and monitoring. Facility design and structural integrity would be a significant and unrelated addition to the NPDES permit program. Any surface impoundment integrity should be linked to the facility design requirements under RCRA Subtitle D.

State dam safety authority, dam safety expertise, and associated regulatory programs are often not housed within State solid waste disposal program or water pollution programs. Likewise, State dam safety programs are not limited to disposal facilities and broadly regulate dams and levees with the guidance of several federal agencies. ASTSWMO understands that that the Association of State Dam Safety Officials (ASDSO) wil l be submitting comments and urges33

EPA to fully consider their comments, including incorporation of federal dam safety guidelines rather than MSHA dam safety guidelines.

EPA Response: EPA, in promulgating the final rule, has taken into consideration sever al dam safety guidance and regulations, including those of FEMA, FERC, US Army Corps of Engineers, US Fish and Wildlife, US Bureau of Reclamation, and MSHA. EPA has fully considered ASDSO’s comments on the proposed rule. EPA has adopted in today’s final ru le specific technical criteria intended to ensure adequate dam safety of CCR surface impoundments, throughout the design, construction, operation, maintenance, and closure of the CCR unit under RCRA Subtitle D standards based primarily of federal
dam safet y guidelines such as FEMA Federal Guidelines for Dam Safety . Today’s final rule includes design requirements for structural stability and operating requirements for hydraulic and hydrologic capacity, inspection requirements, air criteria, and recordkeeping

.

EPA has chosen not to promulgate structural integrity standards based upon the NPDES permit program, agreeing with commenters that this would constitute a significant and unrelated addition to the program.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 09705

- 1 

### Organization 1 

### : Commenter 1 : Robert B. Titus Commenter Type: Private Citizen
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 4.1.1 

### Comment Excerpt Text: With this letter l am requesting that Coal C ombustion Waste (CCW) be regulated under the current provisions of the RCRA Subtitle D. It is my opinion that Subtitle D strikes the correct balance between protecting public health while providing the utility industry with affordable rules by which to dis pose of waste by products.

However, I do believe that coal ash impoundment construction standards must be upgraded. Increased inspection and monitoring of existing and proposed impoundments should be implemented as well.

EPA Response: EPA has adopted in today’s final rule specific technical criteria intended to ensure adequate dam safety of CCR surface impoundments, throughout the design, construction, operation, maintenance, and closure of the CCR unit under RCRA Subtitle D standards based primarily o n federal dam safety guidelines such as FEMA Federal Guidelines for Dam Safety . Today’s final rule includes design requirements for structural stability and operating requirements for hydraulic and hydrologic capacity, inspection requirements, air criteria, and recordkeeping.34



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 09885

- 32 

### Organization 1 

### : Progress Energy, Inc. 

### Commenter 1 : Caroline Choi Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: Development of structural integrity standards for CCR surface impoundments

Progress Energy agrees with EPA’s proposal to incorporate the surface impoundment integrity and inspection obligations into the RCRA program m odeled largely on the standards for coal slurry impoundments regulated by the Mine Safety and Health Administration (MSHA). While MSHA standards regulate a broader array of materials with differing physical properties than CCRs, the MSHA rules provide a go od starting point for developing comparable standards for CCR impoundments.

However, it is important to ensure that the same applicability criteria triggering the obligation to record impoundment information in the company’s operating record apply in trig gering the related obligation to conduct surface impoundment inspections

EPA Response: EPA has adopted in the final rule surface impoundment structural stability and inspection obligations under a RCRA Subtitle D approach modeled partially on the standards for coal slurry impoundments regulated by the Mine Safety and Health Administration (MSHA). However, EPA has revised language in the final rule to also incorporate, in large part, standards and guidance developed by other federal and state agencies charge d with the oversight of dams and other impounding structures. EPA considered guidance and regulation from such agencies as FEMA, US Army Corps of Engineers, FERC, US Bureau of Reclamation, and US Fish and Wildlife, in addition to MSHA. EPA agrees with

comm enters that the MSHA rules provided a good starting point for developing structural integrity and inspection requirements for CCR surface impoundments.

EPA acknowledges that there may have been an error in extending the applicability criteria of
recordkee ping to inspection requirements in the proposed rule. In the proposed rule, the preamble generally stated that the proposed regulatory requirements addressing stability (which included inspections) applied only to those CCR surface impoundments exceeding t he specified size threshold established by the MSHA regulations, the regulatory text required inspections for all CCR units.

The final rule requires weekly general inspections to be conducted for all CCR surface impoundments. Periodic inspections of all CCR units are a necessary practice to ensure that the overall structural integrity of the CCR unit is maintained and that actual and potential structural weaknesses and other hazardous conditions are quickly identified and remediated throughout the active life of the unit. All CCR surface impoundments pose some risk of release

— whether from a catastrophic failure or from a more limited structural failure, such as occurred at Duke Energy’s Dan River plant. Periodic inspections are a generally accepted, prud ent engineering practice that will significantly reduce the risks of such failures; during the Impoundment Assessment Program, EPA discovered that many facilities routinely conduct some sort of periodic inspection and monitoring, although the frequency var ied widely between facilities.35

The final rule merely codifies this practice, by establishing a consistent minimum. EPA is therefore requiring that all CCR surface impoundments be inspected by a qualified person weekly (for visual signs of a potentially ad verse condition)

.



### Comment Number: TRANS

- CHI

- 0018

- 5 

### Organization 1 

### : ALCOA Power Generating, Inc.


### Commenter 1 : Scott Darling Commenter Type: Other Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: ALCOA does agree that there is a need to ensure that surface impoundments are safe in catastrophic failure and we recommend that inspections of surface impoundments by certified professional engineers knowledgeable with dams and ash ponds be conducted annually.

EPA Response: EPA has adopted in today’s final rule specific inspection requirements for annual inspection and quinquennial assessments (i.e., hazard potential assessments, structural stability assessments, safety factor assessments). Both the annual inspections and the quinquennial assessments must be conducted and certified by a qualified professional engineer.

Section 4.4.6.1

- Existing criteria for endangered species and surface water Total Number of Submissions: 1 Total Number of Comments: 1



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 09349

- 19 

### Organization 1 

### : Santee Cooper


### Commenter 1 : Jay Hudson Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment E xcerpt Text: 40 CFR 257.82 (35245) regulates discharges to surface waters, both point and non

- point. However, the NPDES permit process adequately regulates industrial point source discharges from industrial treatment ponds. Duplicate or overlapping regulat ory requirements should be

avoided.36

EPA Response: EPA agrees with commenters that the NPDES permit process adequately regulates industrial point source discharges from CCR units. EPA has removed the surface water requirements proposed under 40 CFR 257.82 from today’s final rule. CCR surface impoundments a re still subject to the existing NPDES permit requirements for discharges to surface water.

Section 4.4.6.2

- Run

- on and run

- off controls Total Number of Submissions: 23 Total Number of Comments: 23



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06252

- 14 

### Organization 1 

### : Minnkota Power Cooperative, Inc. (Minnkota) 

### Commenter 1 : John T. Graves Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text:

EPA should amend its run

- on control requirements for CCR surface impoundments. Current run

on controls were designed for Municipal Solid Waste landfills and are not appropriate for the way impoundments at many power plants are designed.

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend the run

on controls for MSW landfills to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic and hydrologic inflow and outflow as well as the application of this guidance to the CCR surface impoundments evaluated as part of EPA ’s Assessment Program. 5 A review of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for accommodating storm water flows. This was further confirmed by obser vations made during EPA’s Assessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream catchment area to manage CCR, and/or to receive storm water inflow as part of the facility’s overall storm water man agement system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these assessments, EPA considered a number of factors including operating freebo ard, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit operating procedures

5 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequacy of the CCR surface impoundment’s hydrologic and

hydraulic capacity during its assessment effort.37

to make this determination. The adequacy of the capacity was determined using FEMA guidance f

or selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR surface impoundments rather than
“run

- on” and “run

- off” is more directly applicable to the hydraulic and hydrol ogic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or inflow from storm water to CCR surface impoundments . EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood or IDF . Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all CCR surface impoundments to design, construct, operate, and maintain hydraulic and hydrologic capacity to adequate ly manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Potential Classification of the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06254

- 16 

### Organization 1 

### : Sunflower Electric Power Corporation 

### Commenter 1 : Paul E. Reynolds Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text:

EPA should amend its run

- on control requirements for CCR surface impoundments. Current run

on controls were designed for Municipal Solid Waste landfills and are not appropriate for the way impoundments at many power plants are designed.

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend the run

on controls for MSW landfills to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic and hydrologic inflow and outflow as well as the application of this guidance to the CCR surface impoundments evaluated as part of EPA’s Assessment Program. 6 A revi ew of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for

6 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluati ng the adequacy of the CCR surface impoundment’s hydrologic and

hydraulic capacity during its assessment effort.38

accommodating storm water flows. This was further confirmed by observation s made during EPA’s Assessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream catchment area to manage CCR, and/or to receive storm water inflow as part of the facility’s overall storm water managemen t system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these assessments, EPA considered a number of factors including operating freeboard, c atchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit operating procedures to make this determination. The adequacy of the capacity was determined using FEMA guidance for sel ecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR surface impoundments rather than
“run

- on” and “run

- off” is more directly applicable to the hydraulic and hydrologic c apacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or inflow from storm water to CCR surface impoundments. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood or IDF. The refore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all CCR surface impoundments to design, construct, operate, and maintain hydraulic and hydrologic capacity to adequately man age flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Potential Classification of the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06300

- 12 

### Organization 1 

### : Southern Company on behalf of itself and its four subsidiaries: Alabama Power Company, Georgia Power Company, Gulf Power Company, and Mississippi Power Company 

### Commenter 1 : Chris M. Hobson Commenter Type: Electri c Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: 3. Proposed Run

- On Control Requirements Are Inappropriate for Surface Impoundments.

Surface impoundments are designed to collect, store, and manage precipitation. They are not intended, and should not be required, to “prevent flow onto the active portion of the CCB landfill or surface impoundment,” as suggested in proposed 257.81(a)(1). [Footnote 50: Id. at 35245.] A general run

- on standard such as that proposed by EPA is both unnecessary and nonsensical in the context of the typical ash impoundments at Southern Company’s subsidiary utilities. Such impoundments are generally open ponds designed to manage, not avoid, precipita tion. Rather, to39

the extent EPA’s standards allow for continued operation of surface impoundments, any regulatory standard should seek to ensure that the impoundment can manage severe precipitation events (i.e., a 100

- year storm) through some combination o f storage and discharge without overtopping or otherwise malfunctioning

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend run

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements t o prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic and hydrologic inflow and outflow as well as the application of this guidance to the CCR surface imp oundments evaluated as part of EPA’s Assessment Program. 7 A review of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for accommodati ng storm water flows. This was further confirmed by observations made during EPA’s Assessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream catchment area to manage CCR, and/or to receive storm wate r inflow as part of the facility’s overall storm water management system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these assessments, EPA considered a number of factors including operating freeboard, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit operating procedures to make this determination.
The ade quacy of the capacity was determined using FEMA guidance for selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR surface impoundments rather than “run

- on” and “run

- of f” is more directly applicable to the hydraulic and hydrologic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or inflow from storm water to CCR surface impoundments. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydrauli c capacity of a unit, measured by its inflow design flood or IDF. Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all CCR surface impoundments to design, construct, ope rate, and maintain hydraulic and hydrologic capacity to adequately manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Potential
Classification of the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06313

- 98 

### Organization 1 

### : Earthjustice et. al.

7 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequ acy of the CCR surface impoundment’s hydrologic and

hydraulic capacity during its assessment effort.40



### Commenter 1 : Lisa Evans Commenter Type: Advocacy Group
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Oth er Sections: 3.5.2.3 

### Comment Excerpt Text:

Installation of run

- on and run

- off controls should be required for all existing CCR landfills within 6 months of the effective date of the final rule. Six months will be ample time to design and install such controls. Such controls have been an integral pa rt of the design and management
of all Subtitle C and Subtitle D landfills.

Storm water controls are permitted and implemented for construction projects across the United States on a daily basis in order to comply with storm water discharge permits. Such permits routinely require 7

- 10 days to obtain and controls, including diversion structures, silt barriers, and detention structures are constructed over a period of weeks to months. Thus there is no reason to allow more than six months to implement run

- on /run

- off controls at CCR sites.

EPA Response : EPA disagrees with the commenter that run

- on and run

- off controls should be required for all existing CCR landfills within 6 months of the effective date of the rule. The run

on and run

- off (RORO) controls of the final rule require that the owner or operator prepare the

initial run

- on and run

- off control system plan within one year of the effective date of the rule.

Run

- on and run

- off control system plan reporting may require design, construction, and post

cons truction implementation. In instances where run

- on and run

- off capacity is insufficient, installing additional capacity may involve construction of diversion structures such as swales or ditches. Many of these efforts may require several months of design a nd construction, compounded by the fact that much of the work cannot be completed in cold

- weather or heavy

rain seasons.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06352

- 16 

### Organization 1 

### : Dayton Power & Light Company (DP&L) 

### Commenter 1 : JoAnne Rau
Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: C. The proposed subtitle D regulations at 40 CFR §257.81(a)(I) require a "control system to prevent flow onto the active portion of the CCR landfill or surface impoundment" during peak discharge events. A more appropriate way to address this would be to require that the surface impoundment be designed to accommodate peak discharge events rather than to prevent the run

-41

on from occurring. Since most impoundments already are so designed, this would prevent them from having to comply with an unnecessary requirement to prevent run

- on

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend r un

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic an d hydrologic inflow and outflow as well as the application of this guidance to the CCR surface impoundments evaluated as part of EPA’s Assessment Program. 8 A review of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for accommodating storm water flows. This was further confirmed by obse rvations made during EPA’s Assessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream catchment area to manage CCR, and/or to receive storm water inflow as part of the facility’s
overall storm water ma nagement system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these assessments, EPA considered a number of factors including operating
freeb oard, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit operating procedures to make this determination. The adequacy of the capacity was determined using FEMA guidance for selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR surface impoundments rather than “run

- on” and “run

- off” is more directly applicable to the hydraulic and hydro logic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or inflow from storm water to CCR surface impoundment s. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood or ID F. Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all CCR surface impoundments to design, construct, operate, and maintain hydraulic and hydrologic capacity to adequat ely manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Potential Classification of the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06398

- 39 

### Organization 1 

### : Duke Energy 

### Commenter 1 : Mike Stroben Commenter Type: Electric Utility Company

8 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequacy of the C CR surface impoundment’s hydrologic and

hydraulic capacity during its assessment effort.42

Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: Duke Energy agrees with EPA that run

- on and runoff controls are necessary for most surface impoundments and landfills. However, Duke Energy also points out that there are certain exceptions that EPA needs to recognize in the proposed regulatory language. For example, 40
C.F .R. § 257.81 requires a "control system to prevent flow onto the active portion of the CCR landfill or surface impoundment" during peak discharge events. While this requirement may be appropriate for CCR landfills and surface impoundments that are construc ted with above

- ground dikes on all sides, it is a wholly inappropriate requirement for CCR surface impoundments that have been specifically designed to retain stormwater from an adjoining watershed, including those impoundments that have been formed by dam ming a ravine. Such impoundments have already received regulatory review/approval, have been designed with capacity and outlets that are sufficient to deal with the water flow into the impoundment from the natural watersheds during peak discharge events, a nd have operated safely.

Duke Energy recommends that EPA eliminate the proposed prohibition of run

- on into impoundments. Instead, EPA should require that impoundment designs appropriately address the additional flow contributed by stormwater which dischar ges into the impoundment during peak discharge events. In this manner, impoundments that have been designed as described above, and which have been engineered to address peak discharge events, will not be confronted with a
restriction that is both unnecess ary and effectively impossible to satisfy.

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend run

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic and hydrologic inflow and outflow as well as the application of this guidance to the CCR surface impoundments evaluated as part of EPA’s Assessment Program. 9 A review of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for accommodating storm water
flows. This was further confirmed by observations made during EPA’s Assessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream catchment area to manage CCR, and/or to receive storm water inflow as part of the faci lity’s overall storm water management system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these assessments, EPA considered a number of fact ors including operating freeboard, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit operating procedures to make this determination.

9 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequacy of the CCR surface i mpoundment’s hydrologic and

hydraulic capacity during its assessment effort.43

The adequacy of the capacity was de termined using FEMA guidance for selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR surface impoundments rather than “run

- on” and “run

- off” is more directly applicab le to the hydraulic and hydrologic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or
inflow from storm wat er to CCR surface impoundments. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood or IDF. Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all CCR surface impoundments to design, construct, operate, and maintain hydraulic and h ydrologic capacity to adequately manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Potential Classification of the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06529

- 43 

### Organization 1 

### : NiSource Corporate Services 

### Commenter 1 : Dale A. Helmers Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excer pt Text:

Run

- On (40 C.F.R. § 257.81)

While this requirement may be appropriate for CCR landfills, it is not appropriate for CCR surface impoundments that are part of a facility’s stormwater management program. The use of these impoundments to manage storm water is integral to ongoing operations. Prohibiting CCR surface impoundments from receiving run

- on will require construction of new impoundments without providing measureable environmental benefits. This requirement should be deleted

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend run

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic and hydrologic inflow and outflow as well as the application of this guidance to the CCR surface impoundments44

evaluated as part of EPA’s Assessment Program. 10 A review of FEMA guidance co nfirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for accommodating storm water flows. This was further confirmed by observations made during EPA’s As sessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream catchment area to manage CCR, and/or to receive storm water inflow as part of the facility’s overall storm water management system. Moreover, E PA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these assessments, EPA considered a number of factors including operating freeboard, catchment area, hydrolo gic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit operating procedures to make this determination. The adequacy of the capacity was determined using FEMA guidance for selecting and
accommodati ng inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR surface impoundments rather than “run

- on” and “run

- off” is more directly applicable to the hydraulic and hydrologic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or inflow from storm water to CCR surface impoundments. EPA has also concluded th at run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood or IDF. Therefore, EPA is amendin g the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all CCR surface impoundments to design, construct, operate, and maintain hydraulic and hydrologic capacity to adequately manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Potential Classification of the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06532

- 38 

### Organization 1 

### : Southe rn Illinois Power Cooperative 

### Commenter 1 : Leonard F. Hopkins Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text:

Run

- On (40 C.F.R. § 257.81)

10 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequacy of the CCR surface impoundment’s hydrologic and

hydraulic capacity during its assessment effort.45

While this requirement may be appropriate for CCR landfills, it is not appropriate for CCR surface impoundments that are part of a facility’s stormwater management program and run

- on is specifically called for under the facility’s stormwater pollution prevention pla n. The use of these impoundments to manage stormwater is integral to ongoing operations. Prohibiting CCR surface impoundments from receiving run

- on will require construction of new impoundments without providing measureable environmental benefits. This req uirement should be deleted

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend run

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundme nt, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic and hydrologic inflow and outflow as well as the application of this guidance to the CCR surface impoundments evaluated as part of EPA’s Assessme nt Program. 11 A review of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for accommodating storm water
flows. This was further confi rmed by observations made during EPA’s Assessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream catchment area to manage CCR, and/or to receive storm water inflow as part of the facility’s
overall st orm water management system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these assessments, EPA considered a number of factors including ope rating freeboard, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit operating procedures to make this determination. The adequacy of the capacity was determined using FE MA guidance for selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR surface impoundments rather than “run

- on” and “run

- off” is more directly applicable to the hydraul ic and hydrologic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or
inflow from storm water to CCR surface impoundments. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood or IDF. Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all CCR surface impoundments to design, construct, operate, and maintain hydraulic and hydrologic capacit y to adequately manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Potential Classification of the CCR surface impoundment.

11 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequacy of the CCR surface impoundment’s hydrologic and

hydraulic capacity during its assessment effort.46



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06722

- 18 

### Organization 1 

### : Arkansas Electric Cooperative Corporation (AECC) 

### Commenter 1 : Jonathan Oliver Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text:

EPA should amend its run

- on control requirements for CCR surface impoundments. Current run

on controls were designed for Municipal Solid Waste landfills and are not appropriate for the way impoundments at many power plants are designe d.

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend run

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic and hydrologic inflow and outflow as well as the application of this guidance to the CCR surface impoundments evaluated as part of EPA’s Assessment Progr am. 12 A review of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for accommodating storm water flows. This was further confirmed by obse rvations made during EPA’s Assessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream catchment area to manage CCR, and/or to receive storm water inflow as part of the facility’s
overall storm water ma nagement system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these assessments, EPA considered a number of factors including operating
freeb oard, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit operating procedures to make this determination. The adequacy of the capacity was determined using FEMA guidance for selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR surface impoundments rather than “run

- on” and “run

- off” is more directly applicable to the hydraulic and hydro logic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or inflow from storm water to CCR surface impoundment s. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood or ID F. Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all

12 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequacy of the CCR surface impoundment’s hydrologic and

hydrauli c capacity during its assessment effort.47

CCR surface impoundments to design, construct, operate, and maintain hydraulic and hydrologic capacity to adequat ely manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Potential Classification of the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 0 6827

- 12 

### Organization 1 

### : Oklahoma Gas and Electric Company (OG&E) 

### Commenter 1 : Kenneth E. Raymond Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text:

E. Run

- On Control Requirements for CCR Surface Impoundments are Unnecessary Another faulty aspect of the Subtitle D option is the imposition of run

- on controls for surface impoundments. These provisions require a control system to prevent the flow of storm wa ter into a CCR surface impoundment during peak rainfall events. While this requirement may be appropriate for CCR landfills, it is inappropriate for surface impoundments that have been specifically designed and constructed to account for storm water from s uch rainfall events. To address this issue, OG&E suggests iliat the Agency require CCR surface impoundments to be designed to appropriately address peak rainfall events for their particular locations rather than requiring that run

- on into the impoundments must be prevented. By doing so, surface impoundments that have been already been designed and constructed to address such rainfall events will not be confronted with a restriction that is both unnecessary and effectively impossible to meet

EPA Response: EP A agrees with the commenter that it would be inappropriate to extend run

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by

g uidance developed by FEMA for selecting and accommodating hydraulic and hydrologic inflow and outflow as well as the application of this guidance to the CCR surface impoundments evaluated as part of EPA’s Assessment Program. 13 A review of FEMA guidance conf irmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for accommodating storm water flows. This was further confirmed by observations made during EPA’s Asse ssment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream catchment area to manage CCR, and/or to receive storm water inflow as part of the facility’s overall storm water management system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these assessments, EPA considered a number of factors including operating

13 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequacy of the CCR surface impoundment’s hydrologic and

hydraulic capacity during its assessment effort.48

freeboard, catchment area, hydrologi c structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit operating procedures to make this determination. The adequacy of the capacity was determined using FEMA guidance for selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR surface impoundments rather than “run

- on” and “run

- off” is more directly applicable to the hydraulic and hydrologic capacity of CCR surface i mpoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or inflow from storm water to CCR surface impoundments. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood or IDF. Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all CCR surface impoundments to design, construct, operate, and maintain hydraulic and hydrologic capacity to adequately manage flow both into and f rom a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Potential Classification of the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 06863

- 36 

### Organization 1 

### : Avista Corp. 

### Commenter 1 : Darrell Soyars Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text:

EPA Should Amend Its Run

- On Control Requirements For CCR Surface Im poundments One complication of copying the proposed CCR Subtitle D regulations from the MSWLF program is that some of the particular operating requirements for MSWLF landfills cannot be directly applied to CCR surface impoundments. As discussed above, thi s is true in the case of attempting to apply the MSWLF closure time periods to CCR disposal units. Another important example of this is the section of the proposed requirement for surface impoundments and landfills requiring the establishment of specific o perating controls for water run

- on and run

- off.
Id . at 35245 (proposed 40 C.F.R. § 257.81). The run

- on portion of these controls requires a “control system to prevent flow onto the active portion of the CCR landfill or surface impoundment” during peak disc harge events. Id . (proposed 40 C.F.R. § 257.81(a)(1)). While this requirement may be appropriate for CCR landfills (as it is for MSWLFs), it is wholly inappropriate for surface impoundments that have been specifically designed as holding basins
for stormwa ter or that have been formed by damming a ravine and have been designed with
outlets that are sufficient to deal with the water flow from the natural watersheds into the impoundment during peak discharge events. Avista suggests that EPA address the inappl icability of this requirement for these types of49

surface impoundments by instead requiring that CCR impoundments be designed to appropriately address peak discharge events, rather than specifying that run

- on into the impoundment be prevented. In this manne r, impoundments that have been designed as described above and have been engineered to address peak discharge events will not be confronted with a restriction that is both unnecessary and effectively impossible to meet.

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend run

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic and hydrologic inflow and outflow as well as the application of this guidance to the CCR surface impoundments evaluated as part of EPA’s Assessment Progr am. 14 A review of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for accommodating storm water flows. This was further confirmed by observations made during EPA’s Assessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream catchment area to manage CCR, and/or to receive storm water inflow as part of the facility’s
overall storm wate r management system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these assessments, EPA considered a number of factors including operating
f reeboard, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit operating procedures to make this determination. The adequacy of the capacity was determined using FEMA guida nce for selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR surface impoundments rather than “run

- on” and “run

- off” is more directly applicable to the hydraulic and h ydrologic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or inflow from storm water to CCR surface impound ments. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood o r IDF. Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all CCR surface impoundments to design, construct, operate, and maintain hydraulic and hydrologic capacity to ade quately manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Potential Classification of the CCR surface impoundment.

14 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequacy of the CCR surface impoundment’s hydrologic and

hydraulic capacity during its assessment effort.50



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0 640

- 07047

- 26 

### Organization 1 

### : Great River Energy 

### Commenter 1 : Erik Silvola Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: EPA applied run

- on controls to surface impoundments in the proposal. This is appropriate for landfills but not impoundments. Many facilities use CCR impoundments for a number of duties including stormwater management. The proposal should be amended to allow stormwater management in p roperly designed impoundments as this is key for many plants and especially zero liquid discharge facilities.

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend run

- on controls to CCR surface impoundments. In evaluating t he arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic and hydrologic inflow and outflow as well as the application of this guidance to the CCR surface impoundments evaluated as part of EPA’s Assessment Program. 15 A review of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a prefera ble management strategy for accommodating storm water flows. This was further confirmed by observations made during EPA’s Assessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream
catchment area to m anage CCR, and/or to receive storm water inflow as part of the facility’s overall storm water management system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments

. In conducting these assessments, EPA considered a number of factors including operating freeboard, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit operating procedur es to make this determination. The adequacy of the capacity was determined using FEMA guidance for selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR surface impoun dments rather than “run

- on” and “run

- off” is more directly applicable to the hydraulic and hydrologic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or inflow from storm water to CCR surface impoundments. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves deter mining the hydrologic and hydraulic capacity of a unit,

15 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluati ng the adequacy of the CCR surface impoundment’s hydrologic and

hydraulic capacity during its assessment effort.51

measured by its inflow design flood or IDF. Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all CCR surface impo undments to design, construct, operate, and maintain hydraulic and hydrologic capacity to adequately manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Po tential Classification of the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 08220

- 16 

### Organization 1 

### : PowerSouth Energy Cooperative 

### Commenter 1 : Dr. Keith Stephens Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text:

EPA should amend its run

- on control requirements for CCR surface impoundments. Current run

on controls were designed for Municipal Solid Waste landfills and are not appr opriate for the way impoundments at many power plants are designed.

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend run

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic and hydrologic inflow and outflow as well as the application of this guidance to the CCR surface impou ndments evaluated as part of EPA’s Assessment Program. 16 A review of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for accommodating storm water flows. This was further confirmed by observations made during EPA’s Assessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream catchment area to manage CCR, and/or to receive storm water inflow as part of the facility’s overall storm water management system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these assessments, EPA c onsidered a number of factors including operating freeboard, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit operating procedures to make this determination. The adequ acy of the capacity was determined using FEMA guidance for selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related

16 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequ acy of the CCR surface impoundment’s hydrologic and

hydraulic capacity during its assessment effort.52

to “inflow design flood” for CCR surface impoundments rather than “run

- on” and “run

- off” is more directly applicable to the hydraulic and hydrologic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or inflow from storm water to CCR surface impoundments. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydrauli c capacity of a unit, measured by its inflow design flood or IDF. Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all CCR surface impoundments to design, construct, ope rate, and maintain hydraulic and hydrologic capacity to adequately manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Potential
Classification of the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 08270

- 5 

### Organization 1 

### : Cliffs Natural Resources Inc. (Cliffs) 

### Commenter 1 : David Z. Skolasinski Commenter Type: Other Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:
Other Sections: 4.1.3 4.6.1 4.6.1.2 4.4.8.1 4.4.8.2 4.4.8.4 4.4.5.1.1 4.4.5.1.2 

### Comment Excerpt Text: Cliffs Supports EPA's Proposed "Subtitle D Prime" Approach With Modification

Cliffs supports EPA' s effOlis to implement a federal Subtitle D non

- hazardous waste regulatory program for the disposal of CCRs at surface impoundments and landfills. Cliffs, however, is concerned about various aspects of the Subtitle D regulatory approac h provided in the final rule.

One impOliant concern is the automatic closure of CCR surface impoundments at utilities under the proposed Subtitle D regulatory program that are currently operating in a manner that is fully protective of human health and t he environment.

Cliffs suppOlis EPA's alternative "Subtitle D prime" approach because it would ensure the development of fully protective controls for the disposal of CCRs at landfills and surface impoundments. The "Subtitle D prime" approach would provi de the environmental safeguards EP A is seeking while not imposing unnecessary regulatory costs on the utility sector that in turn increases the cost of electricity to electrical rate payers including Cliffs' mines.

Under the "Subtitle D prime" approach, it would include all of the elements of the proposed Subtitle D regulatory program except that it "would not require the closure or installation of composite liners in existing surface impoundments; rather these surface impoundments could continue to oper ate for the remainder of their useful life." 75 Fed. Reg. at 35,210. Thus, the53

"Subtitle D prime" approach avoids a major flaw contained in the Subtitle D regulatory approach that would close down all surface impoundments irrespective of their environmenta l performance. Under the "Subtitle D prime" approach, existing CCR surface impoundments would continue to be subject to applicable groundwater monitoring standards and corrective action requirements.

Certain modifications to the "Subtitle D prime" appro ach should be made, however, if EP A adopts this approach in the final rule. These modifications relate to several of the requirements found in the Subtitle D regulatory program proposed. First, EPA should not adopt a specific timeframe for closure but req uire surface impoundments and landfills to close according to a closure plan approved by a state or developed and certified by a registered professional. Second, EP A should not impose location restrictions on existing surface impoundments and landfills
be cause EPA has provided no evidence in the record to substantiate structural stability issues in
these restricted areas.

Third, EPA should amend its run

- on control requirements for surface impoundments by instead just requiring that these units be designe d to appropriately address peak discharge events. Fom1h, in terms of groundwater monitoring, EPA should allow the state or a registered professional to delete constituents not reasonably expected to be in the waste or establish an
alternative list of in dicator parameters consistent with the groundwater monitoring programs applicable to municipal and non

- municipal solid waste landfills. Fifth, EPA should allow registered professionals to make compliance ce11ifications even if they are employees of the ow ner/operator of the disposal unit. Finally, EPA should allow for alternate liner systems, because in some regions of the country the proposed composite liner system is simply unnecessary to ensure groundwater protection and in other instances an alternate liner system (i.e. geosynthetic clay liners) would be more appropriate that the one proscribed in the proposed rule.

EPA Response: Regarding the comment’s third point, EPA agrees with the commenter that it would be inappropriate to extend run

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic and hydrologic i nflow and outflow as well as the application of this guidance to the CCR surface impoundments evaluated as part of EPA’s Assessment Program. 17 A review of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundme nts was a widely used practice, and a preferable management strategy for accommodating storm water flows. This was further confirmed by observations made during EPA’s Assessment Program; EPA frequently observed units designed to detain or
retain storm wat er inflows of an upstream catchment area to manage CCR, and/or to receive storm water inflow as part of the facility’s overall storm water management system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydra ulic

17 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequacy of the C CR surface impoundment’s hydrologic and

hydraulic capacity during its assessment effort.54

capacity of the CCR surface impoundments. In conducting these assessments, EPA considered a number of factors including operating freeboard, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway prese nce and capacity, and unit operating procedures to make this determination. The adequacy of the capacity was determined using FEMA guidance for selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR surface impoundments rather than “run

- on” and “run

- off” is more directly applicable to the hydraulic and hydrologic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or inflow from storm water to CCR surface impoundments. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and tha t a more appropriate standard involves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood or IDF. Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all CCR surface impoundments to design, construct, operate, and maintain hydraulic and hydrologic capacity to adequately manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Potential Classification of the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 08841

- 29 

### Organization 1 

### : Deseret Generation and Transmission Co

- operative 

### Commenter 1 : Howard Vickers Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text:

EPA should amend its run

- on control requirements for CCR surface impoundments. Current run

on controls were designe d for Municipal Solid Waste landfills and are not appropriate for the way impoundments at many power plants are designed.

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend run

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic and hydrologic inflow
and outflow as well as the application of this guidance to the CCR surface impoundments55

evaluated as part of EPA’s Assessment Program. 18 A review of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for accommodating storm water flows. This was further confirmed by observations made during EPA’s Assessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream
catchm ent area to manage CCR, and/or to receive storm water inflow as part of the facility’s overall storm water management system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these assessments, EPA considered a number of factors including operating freeboard, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit opera ting procedures to make this determination. The adequacy of the capacity was determined using FEMA guidance for selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR s urface impoundments rather than “run

- on” and “run

- off” is more directly applicable to the hydraulic and hydrologic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)

EPA has concluded that it was in appropriate to propose to prohibit all run

- on discharge or inflow from storm water to CCR surface impoundments. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard in volves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood or IDF. Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all
CCR surface impoundments to design, construct, operate, and maintain hydraulic and hydrologic capacity to adequately manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on t he Hazard Potential Classification of the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 08850

- 12 

### Organization 1 

### : Lansing Board of Water & Light (BWL) 

### Commenter 1 : Lansing Board of Water & Light (BWL) Commenter Type: Electric Utility Compa ny Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: The Lansing Board of Water & Light Requests Clarification on Proposed Run

- On and Run

- Off Controls. 277.81(a)(1) requires a control system to prevent flow onto the active portion of the

18 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequacy of the CCR surface i mpoundment’s hydrologic and

hydraulic capacity during its assessment effort.56

CCR landfill or surface impoundment during the peak discharge from a 24

- hour, 25

- year storm must be designed, constructed, and maintained. While we can see logically how this can be done for a landfill, how does this work for a surface impoundment? It is an impoundment.

EPA Response: EPA agrees with the commenter that it would be inappropriate to exte nd run

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydrauli c and hydrologic inflow and outflow as well as the application of this guidance to the CCR surface impoundments evaluated as part of EPA’s Assessment Program. 19 A review of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for accommodating storm water flows. This was further confirmed by observations made during EPA’s Assessment Program; EPA frequently observed units designed to detain o r retain storm water inflows of an upstream catchment area to manage CCR, and/or to receive storm water inflow as part of the facility’s overall storm water management system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hy drologic and hydraulic capacity of the CCR surface impoundments. In conducting these assessments, EPA considered a number of factors including operating freeboard, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation

eve nt, spillway presence and capacity, and unit operating procedures to make this determination. The adequacy of the capacity was determined using FEMA guidance for selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the term inology related to “inflow design flood” for CCR surface impoundments rather than “run

- on” and “run

- off” is more directly applicable to the hydraulic and hydrologic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or inflow from storm water to CCR surface impoundments. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood or IDF. Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface im poundments to require owners or operators of all CCR surface impoundments to design, construct, operate, and maintain hydraulic and hydrologic capacity to adequately manage flow both into and from a CCR surface impoundment during and after the peak dischar ge resulting from the inflow design flood, based on the Hazard Potential Classification of the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 09239

- 71 

### Organization 1 

### : Prairie State Generating Company, LLC (PSGC) 

### Commenter 1 : Keith Bastian

19 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequacy of the CCR surface impoundment’s hydrologic and

hydraulic capacity during its assessment effort.57

Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text:

Run

- On (40 C.F.R. § 257.81) While this requirement may be appropriate for CCR landfills, it is not a ppropriate for CCR surface impoundments that are part of a facility's stormwater management program. The use of these impoundments to manage stormwater is integral to ongoing operations. Prohibiting CCR surface impoundments from receiving run

- on will requi re construction of new impoundments without providing measure able environmental benefits. This requirement should be deleted.

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend run

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic and hydrologic inflow
and outflow as well as the application of this guidance to the CCR surface impoundments evaluated as part of EPA’s Assessment Program. 20 A review of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practic e, and a preferable management strategy for accommodating storm water flows. This was further confirmed by observations made during EPA’s Assessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream

cat chment area to manage CCR, and/or to receive storm water inflow as part of the facility’s overall storm water management system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surf ace impoundments. In conducting these assessments, EPA considered a number of factors including operating freeboard, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit op erating procedures to make this determination. The adequacy of the capacity was determined using FEMA guidance for selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CC R surface impoundments rather than “run

- on” and “run

- off” is more directly applicable to the hydraulic and hydrologic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)

EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or inflow from storm water to CCR surface impoundments. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood or IDF. Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all
C CR surface impoundments to design, construct, operate, and maintain hydraulic and hydrologic

20 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequacy of the CCR surface impoundment’s hydrologic and

hydraulic capacity during its assessment effort.58

capacity to adequately manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based o n the Hazard Potential Classification of the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 09349

- 18 

### Organization 1 

### : Santee Cooper 

### Commenter 1 : Jay Hudson Commenter Type: Electric Utility Company
Classification: Substantive Comment Categor y: Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text: The regulations should clarify that configurations at existing facilities may already meet these requirements, and that the regulations do not mandate new construction in all cases. For example, many impoundments are completely contained within the confines of the embankment dam and do not have an outside watershed contributing to the pond volume. In addition, the NPDES permit process for wastewater treatment ponds routinely requires impoundments to safely contain and allow treatment of the 24

- hr, 25

- year storm event.

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend run

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic and hydrologic inflow and outflow as well as the application of this guidance to the CCR surface impoundments evaluated as part of EPA’s Assessment Program. 21 A review of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for accommodating storm water flows. This was further confirmed by observations made during EPA’s Assessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream catchment area to manage CCR, and/or to rec eive storm water inflow as part of the facility’s overall storm water management system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these a ssessments, EPA considered a number of factors including operating freeboard, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit operating procedures to make this determin ation. The adequacy of the capacity was determined using FEMA guidance for selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR surface impoundments rather than “run

- on” and “run

- off” is

21 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequacy of the CCR surface impoundment’s hydrologic and

hydrauli c capacity during its assessment effort.59

more directly applicable to the hydraulic and hydrologic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit al l run

- on discharge or inflow from storm water to CCR surface impoundments. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood or IDF. Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all CCR surface impoundments to design, const ruct, operate, and maintain hydraulic and hydrologic capacity to adequately manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Potential
Classification of the CCR surface impoundment.

EPA would note that for CCR surface impoundments which already meet these requirements, i.e., do not receive contributory flow from adjoining catchment areas, the CCR unit must comply with the hydrologic and hydraulic requir ements of the rule by ensuring that the CCR unit has sufficient capacity to accommodate direct precipitation from the corresponding design precipitation event.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 09427

- 16 

### Organization 1 

### : San Miguel Electric Cooperative, Inc. (San Miguel) 

### Commenter 1 : Joseph G. Eutizi Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text:

EPA should amend its run

- on control requ irements for CCR surface impoundments. Current run

on controls were designed for Municipal Solid Waste landfills and are not appropriate for the way impoundments at many power plants are designed.

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend run

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting an d accommodating hydraulic and hydrologic inflow and outflow as well as the application of this guidance to the CCR surface impoundments evaluated as part of EPA’s Assessment Program. 22 A review of FEMA guidance confirmed

22 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequacy of the CCR surface impoundment’s hydrologic and

hydraulic capacity during its assessment effort.60

commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for accommodating storm water flows. This was further confirmed by obse rvations made during EPA’s Assessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream catchment area to manage CCR, and/or to receive storm water inflow as part of the facility’s
overall storm water ma nagement system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these assessments, EPA considered a number of factors including operating
freeb oard, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit operating procedures to make this determination. The adequacy of the capacity was determined using FEMA guidance for selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR surface impoundments rather than “run

- on” and “run

- off” is more directly applicable to the hydraulic and hydro logic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or
inflow from storm water to CCR surface impoundments. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood or IDF. Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all CCR surface impoundments to design, construct, operate, and maintain hydraulic and hydrologic capacity to adequately manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Potential Classification of the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 09885

- 24 

### Organization 1 

### : Progress Energy, Inc. 

### Commenter 1 : Caroline Choi Commenter Type: Electric Utility Company
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comment Excerpt Text:

EPA should amend its run

- on control requirements for CCR surface impoundments

One complication of copying the proposed CCR Subtitle D regulations from the MSWLF program is that some of the particular operating requirements for MSWLF cannot be directly applied to CCR surfa ce impoundments. An important example of this is the proposed requirement for surface impoundments and landfills to establish specific operating controls for

water run

- on and run

- off. The run

- on portion of these controls requires a “control system to

preve nt flow onto the active portion of the CCR landfill or surface impoundment” during peak61

discharge events. While this requirement may be appropriate for CCR landfills (as it is for MSWLFs), it is wholly inappropriate for surface impoundments that have been specifically designed as holding basins for storm water or that have been formed by damming a ravine and designed with outlets that are sufficient to deal with the water flow from the natural watersheds into the impoundment during peak discharge events.

P rogress Energy suggests that EPA address the inapplicability of this requirement for these types of surface impoundments by requiring that CCR impoundments be designed to appropriately address peak discharge events, rather than specifying that water run

- on into the impoundment be prevented. In this manner, impoundments that have been designed as described above and have been engineered to address peak discharge events will not be confronted with a restriction that is both unnecessary and effectively impossi ble to meet

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend run

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements to prevent flow onto the CCR surface impoundment, the Agency was strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic and hydrologic inflow and outflow as well as the application of this guidance to the CCR surface impoundments evaluated as part of EPA’s Assessment Program. 23 A review of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for accommodating storm water flows. This was further confirmed by observ ations made during EPA’s Assessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream catchment area to manage CCR, and/or to receive storm water inflow as part of the facility’s
overall storm water mana gement system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these assessments, EPA considered a number of factors including operating
freeboa rd, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit operating procedures to make this determination. The adequacy of the capacity was determined using FEMA guidance fo r selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR surface impoundments rather than “run

- on” and “run

- off” is more directly applicable to the hydraulic and hydrolo gic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or inflow from storm water to CCR surface impoundments. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood or IDF. Therefore, EPA is amending the proposed run

- on

23 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluati ng the adequacy of the CCR surface impoundment’s hydrologic and

hydraulic capacity during its assessment effort.62

and run

- off requirements for CCR surface impoundments to require owners or operators of all CCR surface impoundments to design, construct, operate, and maintain hydraulic and hydrologic capacity to adequatel y manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Potential Classification of the CCR surface impoundment.



### Comment Number: EPA

- HQ

- RCRA

- 2009

- 0640

- 10483

- 50 

### Organization 1 

### : Utility Solid Waste Activities Group (USWAG) et al.


### Commenter 1 : James R. Roewer Commenter Type: Trade Association
Classification: Substantive Comment Category:
Current Task: Examine Context Assigned/Due:



### Comm ent Excerpt Text:

C. EPA Should Amend Its Run

- On Control Requirements For CCR Surface Impoundments

One complication of copying the proposed CCR Subtitle D regulations from the MSWLF program is that some of the particular operating requirements for MSWLF l andfills cannot be directly applied to CCR surface impoundments. As discussed above, this is true in the case of attempting to apply the MSWLF closure time periods to CCR disposal units. Another important example is the proposed requirement for surface imp oundments and landfills to establish specific operating controls for water run

- on and run

- off. Id. at 35245 (proposed 40 C.F.R. § 257.81). The

run

- on portion of these controls requires a “control system to prevent flow onto the active portion of the CCR la ndfill or surface impoundment” during peak discharge events. Id. (proposed 40 C.F.R. § 257.81(a)(1)). While this requirement may be appropriate for CCR landfills (as it is for MSWLFs), it is wholly inappropriate for surface impoundments that have been spec ifically designed as holding basins for stormwater or that have been formed by damming a ravine and have been designed with outlets that are sufficient to deal with the water flow from the natural watersheds into the impoundment during peak discharge event s.

USWAG suggests that EPA address the inapplicability of this requirement for these types of surface impoundments by instead requiring that CCR impoundments be designed to appropriately address peak discharge events, rather than specifying that run

- on in to the impoundment be prevented. In this manner, impoundments that have been designed as described above and have been engineered to address peak discharge events will not be confronted with a restriction that is both unnecessary and effectively impossible to meet.

EPA Response: EPA agrees with the commenter that it would be inappropriate to extend run

- on controls to CCR surface impoundments. In evaluating the arguments against the requirements to63

prevent flow onto the CCR surface impoundment, the Agency w as strongly influenced by guidance developed by FEMA for selecting and accommodating hydraulic and hydrologic inflow and outflow as well as the application of this guidance to the CCR surface impoundments evaluated as part of EPA’s Assessment Program. 24 A review of FEMA guidance confirmed commenters’ contentions that managing flow both to and from dams and impoundments was a widely used practice, and a preferable management strategy for accommodating storm water flows. This was further confirmed by obse rvations made during EPA’s Assessment Program; EPA frequently observed units designed to detain or retain storm water inflows of an upstream catchment area to manage CCR, and/or to receive storm water inflow as part of the facility’s
overall storm water ma nagement system. Moreover, EPA relied on the same FEMA guidance to assess the adequacy of the hydrologic and hydraulic capacity of the CCR surface impoundments. In conducting these assessments, EPA considered a number of factors including operating
freeb oard, catchment area, hydrologic structures’ inflow and outflow ratings, design precipitation event, spillway presence and capacity, and unit operating procedures to make this determination. The adequacy of the capacity was determined using FEMA guidance for selecting and accommodating inflow design floods (IDF) for dams. (Note: The use of the terminology related to “inflow design flood” for CCR surface impoundments rather than “run

- on” and “run

- off” is more directly applicable to the hydraulic and hydro logic capacity of CCR surface impoundments to adequately manage both the inflow and outflow from a design flood.)
EPA has concluded that it was inappropriate to propose to prohibit all run

- on discharge or inflow from storm water to CCR surface impoundment s. EPA has also concluded that run

- on and run

- off criteria are inappropriate for CCR surface impoundments, and that a more appropriate standard involves determining the hydrologic and hydraulic capacity of a unit, measured by its inflow design flood or ID F. Therefore, EPA is amending the proposed run

- on and run

- off requirements for CCR surface impoundments to require owners or operators of all CCR surface impoundments to design, construct, operate, and maintain hydraulic and hydrologic capacity to adequat ely manage flow both into and from a CCR surface impoundment during and after the peak discharge resulting from the inflow design flood, based on the Hazard Potential Classification of the CCR surface impoundment.

24 EPA referred to FEMA’s “Federal Guidelines for Dam Safety: Selecting and Accommodating Inflow

Design Floods for Dams ” in evaluating the adequ acy of the CCR surface impoundment’s hydrologic and

hydraulic capacity during its assessment effort.