Department of Energy 

Carlsbad Field Office 

P. 0. Box 3090 

Carlsbad, New Mexico 88221 

October 7, 2002 

Mr. Frank Marcinowski 

Office of Radiation and Indoor Air 

U.S. Environmental Protection Agency 

401 M. Street, S.W. 

Washington D.C., 20460 

Dear Mr. Marcinowski: 

The Carlsbad Field Office (CBFO) of the Department of Energy (DOE) requests your 

approval of a proposed change to the EPA 40 CFR Part 194 Certification of the Waste 

Isolation Pilot Plant (WIPP) with regard to the design of the Panel Closures. 

Specifically, CBFO requests that the Environmental Protection Agency (EPA) modify 

Condition 1 of the WIPP Certification decision by agreeing that the New Mexico 

Environment Department (NMED) is responsible for final review and approval of the 

design and construction of the panel closure system at WIPP. At the same time, the 

CBFO recognizes that EPA's review and approval of the impact analyses relating to the 

194 Certification Final Rule on Panel Closures is still required, and that EPA must be 

satisfied that any design change will not adversely affect the long-term performance of 

the repository. 

As you know, the purpose of the panel closure system in the WIPP facility is to control 

volatile organic compound (VOC) emissions during the operating life of the facility. The 

panel closure must also protect the health and safety of workers as required by the 

Mine Safety and Health Administration and by the DOE. There are no long-term design 

requirements or performance specifications for these closures, beyond the necessity to 

demonstrate that any design change does not have an adverse affect on long-term 

performance. The analyses that accompany this letter demonstrate that the long-term 

performance of the repository is not sensitive to the closure design, within a broad 

range of likely closure permeability values. 

The CBFO believes it is therefore reasonable that the NMED be responsible for final 

review and approval of panel closure design and construction. The CBFO requests that 

the EPA modify Condition 1 of the Final Rule to recognize this responsibility. We 

suggest that such a change might include the following: 

That the Department will implement a panel closure system as approved by the 

NMED 

That the Department will demonstrate, by an appropriate impact assessment, that 

the panel closure system proposed to NMED does not adversely affect the longterm performance of the repository 

OCT Q 8 ZW2 
Mr. Frank Marcinowski -2- October 7, 2002 

The currently approved panel closure design ("Option D") specified in Condition 1 

involves installation of a concrete block "explosion wall", removal of the DRZ along a 

section of the panel access drifl, and emplacement of a concrete monolith composed of 

Salado Mass Concrete (SMC) in that section of access drift. After three years of 

experience with WlPP as an operational facility, we have re-evaluated a number of its 

engineering and construction aspects. This effort included detailed planning to install 

Option D closures in Panel 1 and a parallel analysis of alternative closure designs. As 

a result of this re-evaluation, we believe a redesign of the panel closure system is 

warranted. The redesigned panel closure (called the WlPP panel closure (WPC)) will 

be much simpler and significantly less expensive to build, will reduce the risk of 

accidents and industrial injury to construction workers, will provide for re-use of mined 

salt, and will reduce the potential for disruption of wasfe emplacement activities. All of 

these benefits will accrue without influencing the short- or long-term performance of the 

repository. 

The proposed change in Condition 1 requires that the EPA be fully cognizant of the 

CBFO's Permit modification request to the NMED for panel closures. To this end, the 

details of the redesign and its performance are included in the attachments to the 

enclosed Notification of Proposed Change. Attachment A of the Notification, Design 

Report for a Revised Panel Closure System at the Waste Isolation Pilot Plant, provides 

a description of the proposed design and demonstrates its adequacy to meet and 

exceed requirements of the Resource Conservation and Recovery Act (RCRA) during 

the operational period. This design report has been certified by a Professional 

Engineer registered in New Mexico. Attachment A is being transmitted to the NMED as 

part of a Permit Modification Request to change the Closure Plan contained in the 

Hazardous Waste Facility Permit (HWFP). 

Attachment B, Effective Permeability of the Redesigned Panel Closure System, 

provides estimates of the permeability of the WPC as a function of time. Specifically, it 

demonstrates that the new closures will have a permeability between m2 and IO-'~ 

m2 throughout the regulatory period. This range is significant because it is consistent 

with the range of panel closure permeability evaluated in Attachment C. 

Attachment C, Panel Closure Impact Assessment Documentation, evaluates the 

impacts of panel closures on the long-term performance of the repository. This analysis 

report is prepared pursuant to 40 CFR Part 191, Subparts B and C, and 40 CFR Part 

194. The report demonstrates that impacts to the predicted long-term performance of 

the repository associated with the installation of the WPC are negligible compared to 

the currently prescribed Option D design. 

The HWFP issued by the NMED specifies panel closure requirements that comply with 

the reauirements of the New Mexico hazardous waste reaulations durina the 

operational period of the repository. The analyses in ~ttichments B an: C 

demonstrate that the long-term performance of the repository is not sensitive to the 

closure design, within a broad range of closure permeability. Because the panel 
Mr. Frank Marcinowski -3- October 7, 2002 

closure specifications cover only the operational period and because long-term 

performance is insensitive to this design, CBFO believes that the NMED, which 

regulates hazardous waste disposal in New Mexico, should have responsibility for final 

approval of the panel closure system design. CBFO therefore requests that EPA 

modify Condition 1 of the WIPP Certification decision to acknowledge that the NMED is 

responsible for regulating the design and construction of the panel closure system at 

WIPP, provided that the Department demonstrates that there are no long-term impacts 

on performance. 

The EPA will continue to be involved as regards the long-term performance of panel 

closures even if Condition 1 is modified. The CBFO must demonstrate to the EPA that 

any future panel closure redesign will have a long-term permeability within a range that 

is acceptable to the EPA, e.g., the range evaluated in Attachments B and C to this 

Notification. If this is not the case, a full performance assessment would be required for 

a new range of closure permeabilities. 

We appreciate your timely consideration of this request. Should you require further 

information, please contact Mr. Daryl Mercer at (505) 234-7452. 

Sincerely, 

Dr. Ines R. Triay 

Manager 

Enclosure 

cc: w/enclosure 

L. Smith, EM-23 

B. Forinash, EPA-ORIA 

C. Byrurn, EPA-ORIA 

S. Ghose, EPA-ORIA 

N. Stone, EPA-Region VI 

S. Zappe, NMED 

M. Silva, EEG 

CC: W/O enclosure 

J. Bearzi, NMED 

C. Zvonar, CBFO 

B. Lilly, CBFO 

J. Pigg, CBFO 

J. Lee, WTS 

P. Shoemaker, SNL 
Mr. Frank Marcinowski 

bcc: W/O enclosure 

J. Plum, CBFO 

D. Mercer, CBFO 

S. Casey, WTS 

R. Chavez, WTS 

October 7, 2002 
Department of Energy 

Carlsbad Field Office 

P. 0. Box 3090 

Carlsbad, New Mexico 88221 

. . 

0 " 0 

2 @$ 

B + <f,hrEs 01' 

Mr. Frank Marcinowski 

Office of Radiation and Indoor Air 

U.S. Environmental Protection Agency 

401 M. Street, S.W. 

Washington D.C., 20460 

Dear Mr. Marcinowski: 

The Carlsbad Field Office (CBFO) of the Department of Energy (DOE) requests yc 

approval of a proposed change to the EPA 40 CFR Part 194 Certification of the W 

Isolation Pilot Plant (WIPP) with regard to the design of the Panel Closures. 

Specifically, CBFO requests that the Environmental Protection Agency (EPA) modif 

Condition 1 of the WIPP Certification decision by agreeing that the New Mexico 

Environment Department (NMED) is responsible for final review and approval oft 

design and construction of the panel closure system at WIPP. At the same time, 

CBFO recognizes that EPA's review and approval of the impact analyses relating t 

194 Certification Final Rule on Panel Closures is still required, and that EPA must 

satisfied that any design change will not adversely affect the long-term performanc 

the repository. 

As you know, the purpose of the panel closure system in the WIPP facility is to cori 

volatile organic compound (VOC) emissions during the operating life of the facility. 

panel closure must also protect the health and safety of workers as required by the 

Mine Safety and Health Administration and by the DOE. There are no long-term de 

requirements or performance specifications for these closures, beyond the necessit 

demonstrate that any design change does not have an adverse affect on long-term 

performance. The analyses that accompany this letter demonstrate that the long-te 

performance of the repository is not sensitive to the closure design, within a broad 

range of likely closure permeability values. 

The CBFO believes it is therefore reasonable that the NMED be responsible for fina 

review and approval of panel closure design and construction. The CBFO requests 

the EPA modify Condition 1 of the Final Rule to recognize this responsibility. We 

suggest that such a change might include the following: 

0 That the Department will implement a panel closure system as approved by the 

NMED 

That the Department will demonstrate, by an appropriate impact assessment, th 

the panel closure system proposed to NMED does not adversely affect the longterm performance of the repository