Department of EnergyWashington, DC 20585

August 2, 1990

Richard J. Guimond, DirectorOffice of Radiation ProgramsU.S. Environmental Protection AgencyWashington, D.C. 20460

Dear Mr. Guimond:

This is to provide you with the Department of Energy's (DOE)comments on Working Draft 2 of 40 CFR Part 191, EnvironmentalRadiation Protection Standards for Management and Disposal ofSpent Fuel, High-Level and Transuranic Radioactive Waste. Thisdraft was placed in your rulemaking docket on January 31, 1990,for information purposes, as part of your efforts to revise 40CFR Part 191 in response to a remand by the U.S. Court of Appealsfor the First Circuit. We hope that you will find theinformation and preliminary views expressed in our commentsuseful in developing a proposed rule.

Since the Environmental Protection Agency (EPA) completed itsscoping calculations on a set of hypothetical high-level wasterepositories as a basis for the standard, much additionalinformation has been developed. For example, specific compliancecalculations have proven much more difficult to complete thanexpected, and the uncertainties in all the models and data setsused in the calculations are much larger than expected. Thehuman intrusion scenarios required by the standard dominatecompliance analyses and make all geologic formations looksimilar. There is now a significant body of data on transuranicand high-level waste and spent fuel and disposal systems. Also,in the years since Part 191 was f irt rpml--- 13ted, the qualifyi ngstatements in it relative to the degree of proof to be requiredhave been interpreted so as to render them virtually meaningless.Furthermore, the Department cannot emphasize enough the need foruniform, consistent, and compatible regulations at the Federallevel. In this regard, we recommend that EPA and the NRCreconcile their regulations to accomplish this objective.

The Department's primary comments on Working Draft 2 are asfollows:

1) DOE supports the clarification of the definition ofundisturbed performance.

2) DOE is concerned with the implementability of thecontainment standards, as they are being interpreted,because of their quantitative, probabilistic nature and thestringency of the numerical release limits.

3) The difference between geologic repositories for

900E"C) re;.0059 90080:2PDeR WASTE DWM-1 PDC~~~~~~~~~~~,~l'

radioactive waste and underground injection wells should beclarified.

4) The consideration of human intrusion should be separatedfrom the complementary cumulative distribution function(CCDF) and treated on a qualitative basis using reasonableassumptions regarding future human behavior such as boreholesealing and passive markers.

5) DOE believes that the assurance requirements in section191.14 are unnecessary, and that their inclusion in the rulewould exceed EPA's regulatory authority.

DOE supports EPA's efforts to develop a generic ground waterprotection strategy and will continue to work with EPA indeveloping such a strategy. However, for the individual andground water protection requirements in 40 CFR Part 191, DOEprefers EPA's Option 1A, no separate ground water requirements,in combination with Options 3A and 4A (1,000 year period ofapplicability and a dose limit of 25 millirem).

These and other important concerns are described more fully inthe enclosed set of comments. The DOE is currently developingpolicy and positions on issues related to the rule, such as theground water protection strategy. Moreover, because DOE has notseen EPA's discussion and rationale for the suggested rulerevisions, these comments cannot represent final DOE positions.DOE expects to submit additional, and possibly revised, commentsas the rule is developed.

We believe, and we know EPA shares our belief, that we have ajoint responsibility to ensure that the wastes covered by thisstandard will be disposed of safely. We appreciate thewillingness of your staff to work with the DOE in developing thenew rule. This will allow the Department's recent uat ad

experience to be considered by EPA. A standard that istechnically justified and capable of being implemented isnecessary for proper disposal to proceed.

Any questions concerning these comments may be directed to me at586-8505 or to Edward Regnier of my staff at 586-5027.

Sincerely,

Raymond F. PelletierDirectorOffice of Environmental Guidance

Enclosure

cc: Mr. Floyd GalpinMr. Robert Browning, NRCMr. Victor Sgobba, GAO

U.S. DEPARTMENT OF ENERGY

COMMENTS ON WORKING DRAFT 2 OF 40 CFR PART 191

DIFFERENCE BETWEEN GEOLOGIC DISPOSAL AND WELL INJECTION

EPA should modify Part 191 to establish unequivocally thedifference between the Underground Injection Control (UIC)program under the Safe Drinking Water Act (SDWA) and the 40 CFRPart 191 environmental radiation protection standards formanagement and disposal of spent nuclear fuel, high-level andtransuranic radioactive wastes in geologic repositories. Failureto clarify this important distinction will cause continuedcontroversy over an issue for which the policy and record areclear. Language which specifically explains that emplacement ofradioactive wastes in a geologic repository does not constituteunderground injection, as defined under the SDWA, should be addedto the rule.

Emplacement of non-liquid radioactive wastes in a geologicrepository does not constitute underground injection (UI) offluids subject to regulation under the SDWA. In its GenericEnvironmental Impact Statement on the Management of CommerciallyGenerated Radioactive Waste (DOE/EIS-0046F, October, 1980), DOEclearly distinguished between the alternative of well injectionand the preferred alternative of disposal in geologicrepositories.

Injection wells are wells in which fluids flow, normally pumpedunder pressure, into formations for the purpose of maintainingpressure in the formation (e.g., for secondary oil recovery) orfor the 4rt 4 7blC Gispos-a of hazardous or toxic waste. But,radioactive waste to be disposed of will not be a fluid and willnot "flow" into a geologic repository and the waste isretrievable for a substantial period of time.

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In the draft 40 CFR Part 193 regulations (April 6, 1989) for themanagement and disposal of low-level radioactive waste (LLW) EPAexpressed an opinion that deep geological disposal is notunderground injection subject to regulation under the SDWA.According to the draft regulation:

EPA does not believe that deep geological disposal ofLLW constitutes emplacement of a fluid within themeaning of the UIC program.... EPA believes that thetime to assess whether the material flows or moves isthe time of emplacement and the term "injection" itselfconnotes delivery by flow. Congress focused oninjection practices when directing EPA to controlunderground injection.... EPA's regulatory program hasalso focused on the identification and control of

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injection practices. Focusing on the practice ofinjection ties the concept of a fluid directly to theemplacement. This connection is expressed practicallyby examining the material at the time of injection and,if the injected material flows into the well, then thewell is subject to the requirements of the UIC program.Therefore, even if deep geological repositories wereconsidered to be wells within the meaning of the SafeDrinking Water Act, the process of lowering the LLWinto a geological formation ... is not considered to bewell-injection because the waste is not fluid at thetime of injection, i.e., it does not flow into theinjection vehicle. The activity therefore is notsubject to the regulatory provisions of the UICprogram.

A discussion of the differences between injection of fluids intoa well and emplacement of radioactive waste in a mined geologicrepository should be included in the preamble to the Part 191regulations to clarify that the SDWA UIC program does not applyto geologic disposal of high-level radioactive waste, spentnuclear fuel, and transuranic radioactive wastes.

In addition, it would be appropriate for EPA to propose thefollowing changes in its definitions for "fluid" and "well" underits SDWA UIC regulations at 40 CFR 144.3 and 146.3 to eliminateambiguity about the possible application of those regulations todisposal of radioactive wastes and spent nuclear fuel in ageologic repository (changes are highlighted):

"Fluid" means any uncontainerized material or substancewhich, at the time of emplacement, flows or moveswhether in a semisolid, liquid, sludge, gas, or anyother non-solid form or state. Radioactive materialsassociated with spent nuclear uei or radioactivewastes disposed of in a geologic repository do notconstitute fluids for purposes of this Subchapter.

"Well" means a bored, drilled-or driven shaft, or dughole, whose depth is greater than the largest surfacedimension. Geologic repositories, for the disposal ofspent nuclear fuel or radioactive wastes, are not wellsfor the purposes of this Subchapter.

Also, add to 40 CFR 144.3 and 146.3 the following definition:

"Geologic repository" means a system which is used for thedisposal of spent nuclear fuel or radioactive wastes in excavatedgeologic media.

Also, add the following to the 40 CFR 144.1 (g)(2) list of itemsnot covered by the UIC regulations:

(vi) Geologic repositories, for the disposal of spent

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nuclear fuel or radioactive wastes.

SECTION 191.01 -- APPLICABILITY

The highlighted language "(except for transportation)" should notbe highlighted as it is not a change from the 1985 rule.

SECTION 191.02(1) -- DEFINITION OF RADIOACTIVE WASTE

The definition of "radioactive waste" in Working Draft 2 on page4 was modified by the addition, without explanation orjustification, of the phrase "and any other radioactive wastematerial managed or disposed of with" high-level or transuranicwaste. The phrase "any other radioactive material" should bedeleted because, to some degree, all materials are radioactive.This modified definition appears to anticipate the possibility ofdisposal of greater-than-Class C (GTCC) low-level waste in ageologic repository subject to Part 191. If EPA's intention isto include GTCC radioactive wastes, then the definition should bemodified to include that additional term, and only that term.Even though additional waste has been included in the "units ofwaste" for determining the allowable release to the accessibleenvironment (Appendix B of Subpart B, Note 1), no basis isprovided for establishing the equivalency of either 1 million or100 million curies of this material to 1,000 MTHM.

The data supporting the 1985 rule provides no basis forjustifying application of the numerical limits in the rule toGTCC waste. The 1985 rule was developed by assessing theachievability of, and risks from, the disposal of high-levelwaste and the conclusions of this analysis are not directlytransferable to GTCC waste, or to "any other radioactivematerial."

SECTION. 191.03 -- STANDARD

Section 191.03 should incorporate the committed effective doseequivalent concept utilized in Sections 191.15 and 191.16 ratherthan the outdated dose limits of 25 mrem to the "whole body" and75 mrem to any critical organ. Dose limits in both Subparts of40 CFR Part 191 should be in terms of the effective doseequivalent to be consistent with the internationally acceptedapproach.

SECTION 191.12(e) -- DEFINITION OF COMMITTED EFFECTIVE DOSEEQUIVALENT

The definition of the term "committed effective dose equivalent"(CEDE, page 8) is incorrect. The CEDE is not "the total doseequivalent received by an individual..., multiplied by

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appropriate weighting factors...." The CEDE is the sum of thedoses to specified organs of an individual which have beenmultiplied by appropriate weighting factors (the multiplicationprecedes the summation). The established and widely accepteddefinition of the term in the National Council on RadiationProtection and Measurements (NCRP) Report 91 or EPA PublicationEPA-520/1-88-020 should be used.

In addition, the equation for "committed effective doseequivalent" on page 22 should be corrected. Because the timeintegration is to be carried out first, the equation (with a 50year dose commitment) should read:

HE. 50= E WTHSO-T

The period of the dose commitment specified by the InternationalCommission on Radiation Protection (ICRP) and the NCRP is fiftyrather than seventy years as proposed in Working Draft 2.Extension of this period to seventy years would requiredevelopment of new dose conversion factors and is unnecessaryconsidering the low likelihood that individuals would be exposedto the releases for their entire lifetimes and otheruncertainties in the calculation of committed effective doseequivalent (e.g., suitability of using the listed values forweighting factors, developed for occupational exposures, forassessing public exposure). DOE recommends that EPA use theICRP/NCRP approach of 50-year dose commitments in the 40 CFR Part191 rulemaking.

SECTION 191.12(i) -- DEFINITION OF ECOLOGICALLY VITAL GROUNDWATER

A definitfon has been added for "ecologically vital ground water"(pages 8-9). This groundwater supplies "an aquatic orterrestrial ecosystem which is located either in a ground waterdischarge area and supports a habitat for a listed or proposedendangered or threatened species, as designated pursuant to theEndangered Species Act, as amended, or, on Congressionallydesignated Federal Lands managed for the purpose of ecologicalprotection regardless of the presence of threatened or endangeredspecies." Ecologically vital ground water is one of theresources to be avoided during site selection (p. 12, 191.14(g)).The term also is included in the definition of Class Igroundwater under Option 1 for the Individual Protection andGround Water Protection Requirements (page 14, definition (b)).

DOE has two concerns about the proposed definition of"ecologically vital ground water." First, it is uncertain whichspecies will be endangered or threatened in the future or whichlands Congress will designate in the future, as Federal landsmanaged for the purposes of ecological protection. Therefore,

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the word "currently" should be inserted before each of the words"listed," "proposed," and "Congressionally." Second, thedefinition is too broad. Under the definition in WorkingDraft 2, the ground water does not have to be vital, or evenimportant, to the maintenance of the ecosystem. The definitionshould be revised to read "... ground water providing anessential supply to an aquatic or terrestrial ecosystem which islocated either in a ground water discharge area and supports acritical habitat .... " (changes highlighted). Without the word"critical" prior to habitat, any groundwater system discharginginto an endangered or threatened species habitat would beclassified as ecologically vital, regardless of its importance tothe species. If the word "critical" were included, thedefinition would apply only to ground water systems that weretruly vital to an endangered or threatened species.

SECTION 191.12(1) -- DEFINITION OF IMPLEMENTING AGENCY

Differences of opinion on the appropriate classification to beassigned to specific ground water supplies may occur. The ruleshould make it clear that the implementing agency is responsiblefor classifying the ground water. This clarification would beconsistent with the draft 40 CFR Part 193 regulations.'

SECTION 191.12(n) -- DEFINITION OF MAN-MADE RADIONUCLIDE

A definition has been added for "man-made radionuclide" (page 9)."Mill tailings or other radioactive materials stored or disposedof by man .... " (emphasis added) are expressly included as manmade radionuclides" for purposes of Subpart B. Virtually allmaterials stored or disposed of by man have some small amount ofradioactivity. No de minimis level has been established toprovide appropriate qua'f'cation to the term "other radioactivematerials". Also, it is unclear whether "man-made radionuclide"includes that portion of background radiation resulting fromweapons testing in the 1950s and 1960s. Further, by using theterminology "any radionuclide" instead of "any radioactivematerial," it is not clear whether this definition would includenaturally occurring materials containing radionuclides which, inother circumstances, have previously been classified as byproductor special nuclear materials. This ambiguity results because thecommon usage of the term "radionuclide" is to refer to a speciesof atom. For the above reasons, the proposed definition is toobroad, technically questionable, and could set an undesirableprecedent. This definition should be deleted from Subpart B.

SECTION 191.12(q) -- DEFINITION OF UNDISTURBED PERFORMANCE

DOE agrees with the modified definition of "undisturbedperformance" (page 10) used in Working Draft 2. The applicationof this definition would limit consideration of scenario

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probabilities to the containment requirements in Section 191.13.Eliminating required consideration of disruptive external naturalevents in determining compliance with individual and ground waterprotection requirements removes unnecessary uncertainty from thedose calculations. DOE recommends that appropriate language fromthe guidance in Appendix C be more explicitly reflected in thedefinition itself.

SECTION 191.13 -- CONTAINMENT REQUIREMENTS

The DOE is concerned with the implementability of the containmentrequirements as they are being interpreted. A literalinterpretation of the requirements would preclude the use ofqualitative judgment by the implementing agency as intended byEPA. Without a significant measure of qualitative judgmentallowed by the rule, the combination of the quantitative,probabilistic nature of the standard and the stringency of thenumerical limits for allowable releases would make it difficultto demonstrate compliance at any site. In addition, risk levelsimplied by these release limits are inconsistent with thecriteria and methodologies established by the InternationalCommission on Radiological Protection (ICRP) - theinternationally recognized body for establishing radiationprotection standards. The standards should be consistent withthe principles and criteria established by the ICRP; anyinconsistencies should be technically justified and fullydocumented.

Given the current probabilistic nature of the standard, DOEbelieves that some wording changes are needed to assure that thecontainment requirements are not misinterpreted and a morestringent requirement imposed than originally intended. TheAugust 1985 rule contained several qualifying statements relativeto the degree of proof to be required and provii-ay Zui:incorporating performance assessment results into a complementarycumulative distribution function (CCDF) only to the extentpracticable. These qualifying statements were believed essentialto the implementability of the standard. Unfortunately, the NRCstaff, and others, seem to have overlooked and/or misinterpretedthese qualifying statements so as to render them virtuallymeaningless. DOE believes that the following additions to theproposed rule are necessary to assure that the rule isimplemented as EPA intends (changes highlighted):

191.13(a) Disposal systems for spent nuclear fuel or high-level or transuranic radioactive wastes shall be designed toprovide a reasonable expectation, based upon performanceassessments and qualitative judgments, that the cumulativereleases ---.

191.13(b) Complete assurance that the requirements of191.13(a) will be met is not required. --- Instead what isrequired is only a reasonable expectation, based on

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qualitative judgments and performance assessments, thatcompliance with 191.13(a) will be achieved.

In Appendix C the following should be added after the firstparagraph: In determining compliance with these regulationsthe standard of proof required is a "reasonableexpectation." This standard of proof is not the same as"reasonable assurance," as that term is used in NRCregulations in Title 10. A "reasonable expectation" allowsa substantially greater degree of uncertainty than does"reasonable assurance." This is appropriate because of theuncertainties associated with predicting environmentalconditions and geologic and hydrological phenomena overunprecedented periods of time. The terms are notinterchangeable.

Appendix C, Compliance with Section 191.13. Add followingthe first sentence: It is intended that the abovequalifier, "whenever practicable," be applied in a manner togive it significant effect and to facilitate implementationof this rule. The Agency expects that there will likely beinstances where it is not practicable to assemble theresults of performance assessments into a CCDF, for example,due to unavailable data, uncertainties in data, orinadequacy of models for describing long term future eventsand processes. The resulting impracticality could be eithera practical inability to execute the calculations or a CCDFwith such a large band of uncertainty surrounding it as tomake it essentially meaningless.

Revise the last sentence of the first paragraph of AppendixC, compliance with Section 191.13, as follows: The Agencyassumes that a disposal system can be considered to be incompliance with Section 191.13 if, considering this singledistribution function and relevant qualitative factors,'EGrSeis a reasonable expectation that the disposal system willmeet the requirements of Section 191.13(a).

Human Intrusion Considerations

The standard should be revised so that consideration of humanintrusion is separated from the CCDF. In 1985, the methodologyproposed for evaluating compliance could be tested only intheory. Since that time, data and understanding have beendeveloped by the Department to complete a preliminary analysisfor the WIPP repository. This first real-system analysis showsthat the human intrusion considerations in the containmentrequirements dominate the analysis. It is not technicallypossible to use human-intrusion analyses to compare geologicformations for siting repositories because the intruding boreholebypasses the host formation and removes it as a barrier toradionuclide transport. Analysis of the probability of humanintrusion requires projection of future societal requirements andactivities. Uncertainties in these projections dominate and are

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propagated throughout the analyses. The unfortunate result isthat the standard provides little incentive to locate arepository in a site with favorable geologic properties, andminimizes these properties in the performance process.

This is exactly opposite EPA's stated intent that the humanintrusion scenario provide a basis for comparing alternate sites.Thus, the standard should be revised so that consideration ofhuman intrusion is separated from the CCDF and treated on aqualitative basis using reasonable assumptions regarding futurehuman behavior such as borehole sealing and passive markers.The Department is continuing to evaluate human intrusion issuesand will provide more specific suggestions in the near future.For example, the Department is in the process of analyzing theimplications of future societal requirements and activities forthe WIPP Project. This effort should provide useful insightsinto the feasibility of evaluating human intrusion scenarios. Areport discussing the impacts of human intrusion on thecontainment analysis and on the repository design is expected tobe available within a few months.

SECTION 191.14 -- ASSURANCE REQUIREMENTS

The Department believes that the Assurance Requirements inSection 191.14, which are applicable only to facilities notregulated by the Commission, are unnecessary and that theirinclusion in the rule exceeds EPA's regulatory authority toestablish generally applicable environmental standards forradiation protection under the Atomic Energy Act of 1954 andReorganization Plan No. 3. Requirements for site selection, fordesign of disposal systems, for monitoring and for permanentmarkers are the responsibility of the implementing agency, notEPA. Although DOE intends to incorporate the requirements ofthese assurance requiraints int 1 its planning, the Departmentobjects to EPA imposing the requirements as a part of the 191Standards.

In addition to exceeding EPA's authority, the new 40 CFR191.14(e) is unacceptably ambiguous. The term "maximumachievable control technology" (MACT) in the context of 40 CFRPart 191 is unclear. The technical community, including the NRC,is in agreement that the release limits specified in.Table 1 areso restrictive as to constitute de facto compliance with theALARA concept. Applying a new concept of MACT to a geologicrepository is inappropriate, primarily because of the passivenature of such a facility and its functional lifetime. Thisrequirement would make the natural system itself subject to MACT;an unwarranted and unworkable extension of the concept. The DOEstrongly opposes the use of MACT in Section 191.14(e) andunderstands from discussions with EPA staff that EPA plans toeliminate this assurance requirement from the next draft. DOEstrongly supports deleting this assurance requirement; however,it should not be replaced with a requirement for ALARA. An ALARA

8

requirement would be inappropriate because of the extremely lowrelease limits in the rule and is inappropriate for geologicsystems and for time frames where action cannot be taken tocontrol unplanned releases.

Further, the new assurance requirement added for a 100,000 yearprojection of undisturbed performance when comparing alternativesites Section 191.14(f)] is unacceptable. Predictions beyond10,000 years are extremely speculative and not justified on thebasis of protection of human health or the environment. Thisrequirement addresses the site selection process. Involvement insite selection is not an appropriate role for EPA. Moreover, theU.S. Court of Appeals in the decision vacating and remanding thisrule specifically found that the 10,000 year time period ofconsideration was adequately justified.

The only stated purpose for the assurance requirements in 191.14is "To provide the confidence needed for long term compliancewith the requirements of 191.13 ---. " The only basis suggestedin the rule for the assurance requirement in 191.14(g) -avoidance of areas where there is an expectation of explorationfor resources - is to reduce the chances that people mayinadvertently disrupt a disposal system. Although it is notclear, the term "valuable geologic formation" would seem to referto valuable in an aesthetic or academic sense and not to economicvalue, because mineral, petroleum, gas and water resources arecovered in other clauses.

In Section 191.14(g) "water for agricultural use" and "groundwaters that are ecologically vital" have been added to the listof resources to be considered during site selection.

The requirements to avoid valuable geologic formations, groundwater which may be extracted outside the controlled area fordrinking or agricultural use, and ecolg±ca'' vital groundwater, are without justification because such resources would notmake disruption by exploration at the site any more likely.These requirements apparently are intended, not to assure theperformance of the repository, but-rather to protect theresources. It is not clear that EPA has authority to promulgateregulations protecting "valuable geologic formations" and (asdefined under ecologically vital) "endangered species" and"Federal lands managed for the purpose of ecologicalprotection ---. " In any event, no basis has been provided toestablish that location of a repository or any potential releasesof radioactive material from a repository would causeunacceptable harm to these resources. Therefore, the aboveenumerated resources should be deleted from the list of those tobe avoided.

Further, the identification of the ground waters to be consideredin this section is unnecessarily complicated because the term"water for agricultural use" has not been defined in Section191.12 and terminology found in existing legislation has not been

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used. As previously discussed, DOE recommends that all ofSection 191.14 be deleted. However, if it is retained, DOEsuggests that the Section 191.14(g) requirement should bereworded as follows (changes highlighted):

Places where there has been mining for resources, orwhere there is a reasonable expectation of explorationfor resources that, based on current knowledge, arepredictably scarce or easily accessible, or where thereis a significant concentration of any material that isnot widely available from other sources, should beavoided in selecting disposal sites. Resources to beconsidered shall include minerals, petroleum or naturalgas of currently recognized economic value or strategicimportance; ground waters inside the controlled areathat are currently either a sole source of drinking water asdefined in the Water Quality Act of 1987 and the CleanWater Act of 1977 as amended or ground waters whichserve an area classified as prime farmland subject toprovisions of the Farmland Protection Act. Such places ---.

The above suggested changes more precisely define resources to beavoided.

SECTIONS 191.15 & 191.16 -- INDIVIDUAL AND GROUND-WATERPROTECTION REQUIREMENTS

DOE recommends the adoption of Option 1A for Section 191.15 and191.16. DOE cannot support either Options B, or 2B as outlinedin the Working Draft 2 proposal. They should be deleted from theproposed rule for the following reasons:

1. There is no adequate rationale for the dual dose-limiting-standards under Options 1B and B of 4 mrem/yr for gou-water pathways and 25 or 10 mrem/yr for all pathwayscombined. Both sets of standards govern the sameradioactive waste disposal activity. In Options B and 2B,EPA proposes to formulate a separate ground water pathwayrequirement even though the 25 mrem/yr individual dose limitwould control the dose from all pathways combined, includingthe ground water pathway. EPA has provided neither ahealth-based justification nor a cost-benefit optimizationrationale for a separate ground water provision.

2. There is no statutory requirement for a separate groundwater pathway standard.

3. EPA has not presented any rationale or technicaljustification for the Option B proposed zero degradationstandard for Class I ground water. Also, many qualitativeterms in the definitions of the ground-water classes arevague. For example, the term "interconnected" in thedefinitions for Class IIIA and IIIB ground waters under

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Option 1 (page 14) is vague and should be defined to avoidcompliance demonstration problems. The quantitativemeasures associated with determinations of "potable groundwater" and "high-yield aquifer" have not been peer reviewedor otherwise technically justified.

4. Option B relies on EPA's internal ground-water protectionstrategy, which has never been formally proposed and isundergoing revision. This classification system, whichdivides ground waters into various classes based onqualitative and quantitative measures, should beappropriately justified and established by rulemaking beforeits incorporation into any other regulations.

5. Preexisting background radiological dose from natural orman-made radionuclides should not be incorporated into theproposed Section 191.16 standards (Options B and 2B). IfEPA decides to include separate ground-water standards inthe rule, DOE strongly believes that the standards should beapplied only to radionuclides and pathways from the disposalsystem itself.

DOE generally supports Option 1A because it does not rely on thedraft ground-water classification system and contains onestandard for all pathways of exposure. Option 1A should be theonly regulatory approach presented in the proposed rule.Although Option 2A is a similar standard, the term "high-yieldaquifer" is more precisely defined and more restrictive than"potable water." Formations may contain potable water, but maybe over 2,500 feet below the land surface and not able to producesignificant quantities of water for human use. However, it isnot apparent that the quantitative measures defining a"high-yield aquifer" are appropriate. For example, the limit of10,000 mg/L total dissolved solids may not be appropriate for alltypes of dissolved A imit for individual species (e.g.,carbonates, phosphates, brine) may be more appropriate.Under Option 1A, DOE supports a dose limit of 25 mrem (Option 4A)and a time period of 1,000 years (Option 3A) as part of theIndividual and Ground water Protection Requirements. Otheroptions are inappropriate and should not be presented in theproposed rule. DOE believes that the 25 mrem dose limit for allpathways combined provides an adequate margin of safety inprotecting the public health. Extension of the Individual andGround water Protection Requirements to 10,000 years would likelycomplicate demonstration of compliance without necessarilyincreasing the degree of public protection due to the increaseduncertainty in the projection of performance. Although AppendixC provides additional clarification on implementation of thestandard, projecting climatic changes and socio-cultural factors,such as population, agriculture, and lifestyle statistics, over10,000 years with any certainty, is not likely to be possible.At a minimum, this difficulty is appropriately addressed inAppendix C's recognition of the need for "expert judgment." Inaddition, because the NRC is not bound by the language in the

11

appendix, it is not certain that EPA's assumptions regardingqualifying statements and strictness of interpretation will bereflected in NRC's licensing process.

DOE supports the guidance provided by Appendix C in WorkingDraft 2, particularly the concept of "undisturbed performance"(related to gradual processes) and "best estimate predictions"(used to analyze compliance).

SECTION 191.17 -- DEMONSTRATION OF CAPABILITY TO COMPLY

Working Draft 2 added a new Section 191.17 on demonstration ofcapability to comply. The new section requires preliminaryperformance assessment calculations (which are undefined),written test plans for experiments, plans and tested proceduresfor the removal of the waste, and concurrence of the EPAAdministrator before temporary emplacement of the waste when theimplementing agency is not the Commission. For WIPP, test plansalready exist; the DOE has committed to plans and testedprocedures for waste removal; and the EPA has indicated that theyare in favor of the tests. Thus the WIPP already seems to becomplying with these requirements; and, by the time this rule ispromulgated testing should be well underway. However, thissection exceeds EPA's authority and should be deleted. EPA hasno statutory authority to implement the standards or to requireconcurrence in an implementing agency's determination.

APPENDIX B NOTE 1 -- UNITS OF WASTE

Several independent assessments of health effects of HLW and TRUwastes have arrived at different equivalencies for some of theradionuclides in the table. To clarify the basis for theequivalency factor used, EPA should iplian its methodology fordetermining that 1000 MTHM HLW is the equivalent, for thepurposes of this standard, of 1,000,000 Ci TRU waste.

Note 1(e) should be revised to include additional nuclides asfollows:

(e) an amount of transuranic (TRU) waste containing1,000,000 total curies of 1) alpha emitting transuranicradionuclides with half-lives greater than 20 years, 2)radionuclides with half-lives less than 20 years whichproduce regulated daughters with half-lives longer than20 years, and 3) any other regulated radionuclidescontained in the (nominally) TRU waste.

This language would include plutonium-241 (half-life 14+ years)and other like radionuclides in the waste unit. Plutonium-241emplaced in the repository rapidly decays to become regulatedradionuclides with half-lives greater than 20 years. Thenuclides described in 2) and 3) above will comprise about half of

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the initial inventory in the repository.

APPENDIX C -- GUIDANCE FOR IMPLEMENTATION OF SUBPART B

Compliance with Section 191.13

It is not clear whether the guidance suggests combining multipledistribution functions into a single function or consideration ofmultiple distribution functions instead of using a singledistribution function. Some ambiguity has resulted from thereference to a single distribution function in the firstparagraph while referring to distribution function(s) in thesecond paragraph. This could be clarified by revising the secondparagraph to read:

"--- use prevalent expert judgement to assist it indetermining which distribution function(s) to consider andwhether to combine them in evaluating compliance with191.13."

Frequency and Severity of Inadvertent Human Intrusion intoGeologic Repositories

After the second sentence insert the following:

"These parameters represent the most pessimistic upper boundthat ever need be assumed. They are not required to be usedby the implementing agency. Instead of assuming theseparameters, the implementing agency is encouraged to developand use a probability distribution function for boreholedrilling rates which is justified for application at theparticular site under consideration."

P--Rvisa the last sentence to read:

... newly sealed in accordance with the least protectivepractices required by current law for exploratorydrilling... These consequences represent an upper bound andare the most pessimistic that ever need be assumed. Theyare not required to be used by the implementing agency whichis encouraged to develop and justify the use of otherconsequences. For example, the permeability of an intrudingborehole may be represented by a distribution foruncertainty analysis.

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