ML20033D961

Recommends Commission Approve Proposed Policy Statement on Exemptions from Regulatory Control for Practices W/Public Health & Safety Impacts Below Regulatory Concern

ML20033D961
Person / Time
Issue date:	09/09/1988
From:	Stello V NRC OFFICE OF THE EXECUTIVE DIRECTOR FOR OPERATIONS (EDO)
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References
TASK-PINV, TASK-SE SECY-88-257, NUDOCS 8809160061
Download: ML20033D961 (58)

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{{#Wiki_filter:f :: [,;; m:~. A } t l 4 7 [Sn ato5 E ~ 4 / s, POLICY ISSUE September 9, 1988-(Notation Vote) stev-es-2sv For: The Comissioners From: Victor Stello, Jr., Executive Director for Operations

Subject:

PROPOSED COMMISSION POLICY STATEMENT ON EXEMPTIONS FROM REGULATORY CONTROL FOR PRACTICES WHOSE PUBLIC HEALTH AND SAFETY IMPACTS ARE BELOW REGULATORY CONCERN (BRC)

Purpose:

To provide for Comission consideration, a proposed policy L statement on exemptions from regulatory control for practices. whose health and safety impacts are below regulatory concern. l l Summary: This paper discusses a proposed policy statement whose purpose L is to establish the basis upon which decisions can be made by E the Commission involving exemptions from regulatory control. The principles, technical considerations and risk basis for the development of this policy are outlined and'the constraints and criteria for decision making are presented. Included among these are numerical criteria which define a range of individual and collective doses (below 10 mrem per year and 100 person-rem per year) which can be considered ALARA without further cost-benefit analysis. There has been extensive L interoffice coordination in development of the proposed l policy, however, there remain some views favoring different l numerical criteria. Discussion: The Staff' Requirements Memorandum of March 30, 1988 l (Enclosure 1) directed the staff "... to submit for Comission l consideration options for a Comission policy which establishes a generic numbe Kfor exposures which are below regulatory concern." The staff was further directed to "... discuss the I approach for implementing such a number for multiple sources L of licensed activities which does not require justificauen by l. individual licensees." A proposed policy statement is provided as Enclosure 2. In the proposed policy, a practice is defined as an activity or a set or combination of a number of similar sets of coordinated L and continuing activities aimed at a given purpose which could involve the potential for radiation exposure. Under this

Contact:

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r'~ ~' e j .,. 4 L j ,.j The' Comissioners 2 i proposed policy, the definition of " practice" is a critical feature which will: assure that the formulation of exemptions from regulatory control will not allow deliberate dilutien i of material or fractionation of.a practice for the purpose of l circumventing controls' that would otherwise be applicable. The policy statement draws upon the basic concepts of radiation protection, These are (1) justification of practice, (2) dose limits-to define the maximum allowed dose to an individual,and(3)enhancedsafetythroughachievingdoses which are ALARA (as-low as reasonably achievable). In employ-ing these concepts to develop the policy, the possibility that some individuals could experience radiation exposure from more than ore aractice has been a key consideration, To der e if an exemption for a practice is appropriate, the stafi' believes the Comission must determine whether one of the following conditions is met: (1) the' application or continuation of regulatory controls does not result in any significant reduction in the individual or collective dose or (2) the costs of the regulatory controls that could be imposed to reduce the individual. and collective dose are not balanced by a comensurate risk reduction, To quantify the residual risks from the low doses associated with exempted practices -the proposed policy subscribes to continued Commission use of a hypothetical linear relationship between dose and health effects, Based on this relationship, two risk-based criteria are proposed for demonstrating that ALARA has been achieved for practices being considered for exemption. For justified practices involving individual radiation exposures below approximately 10 mrem per year,' and collective doses less than approximately 100 person-rem per-year, exemptions may be granted-without the necessity-of cost benefit analyses to demonstrate that risks are ALARA. Exemp-1 tion proposals not meeting these criteria may be granted based on appropriate cost benefit analyses. The risks associated with the 10 mrem per year individual dose and a 100 person-rem collective dose criteria are believed to be small based on the linear dose-effect model. This model, in its simplest form, equates by direct proportion the risk of a statistical health effect (e.g., random risk of radiation induced cancer or genetic effect) from a radiation exposure to the level of. that exposure, even down to the smallest exposure. The use of individual or collective dose to define a threshold for exemption decisions is not based on an assertion that there is no biological damage or risk at these defined dose levels. Rather, the adoption of these criteria is based on the argument that the risk entailed below these exposure levels is sufficiently low in absolute magnitude and in

,i' L w ) V nThe Comissioners - 3 [ -) . comparison to everyday risk as te be beneath any reasonable threshold of concern. A radiation exposure of 10 mremL corresponds to an incremental. annual individual risk of cancer - fatality which is 0.1 percent' of the individual's annual. risk _ i of a cancer _ death. In essence this low level of risk is i completely consistent with the Comission's Safety Goal Policy Statement for the operation of comercial nuclear power reactors. For practices involving collective doses 'i below 100 person-rem, the risk of fatality would be very unlikely. The proposed policy also includes Comission guidance t regarding frivolous practices for which regulatory exemptions normally will not be considered. This guidance on frivolous practices, in combination with the criteria for ALARA and the; staff's intention to take into consideration the possibility -of multiple exposures in evaluating exemption proposals, provides assurance that it will be unlikely than any individual will receive a dose above the limit due to exposure to more-than one exempted practice._ The proposed policy statement includes the staff's ~ recommendations of individual and collective dose values that provide the criteria for basing exemption decisions on simple demonstrations of justification and ALARA. Additional perspective on these values is included in Enclosure 3. This enclosure also discusses the-pros and cons of alternative numerical values. discusses three major policy considerations including: (1) the principle of " justification of practica", (2) whether certain practices should be excluded from the exemption policy, and (3) approaches for the calcu-lation and use of collective dose assessments.. Enclosure 5 contains responses to the Comission's request for an explicit identification of the assumptions and projected risk estimates K, used to establish certain BRC limits currently included in NRC regulations.- This enclosure also discusses the uncertainties in-the data base regarding the coefficients-relating radiation-dose to health ri3k. A sumary of the staff's recomendations on the major policy considerations, discussed in enclosure 4, is as follows: Justification: l " Justification of practice" is a basic element of I' existing radiation protection policy currently applied both nationally and internationally. The staff recommends that " justification of practice" should be required before any regulatory exemption is allowed. The Advisory Committee on Nuclear Waste (ACNW) supports this recomendation, l b

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i =, d' d The Commissioners-4 i Exclusions: i The policy identifies specific practices which should be excluded from the exemption policy. This exclusion provision reflects the staff's concerns regarding the social and ethical questions about the acceptance of small radiological risks associated with frivolous or 1 unjustified practices. The ACNW agreed with this staff. position but emphasized that care must be exercised in defining frivolous practices. Calculation and Use of Collective Dose Assessments: The collective dose associated with an exempted practice can serve as both a measure of-the impact on the exposed i population and a mechanism.for assessing the benefits of regulatory constraints on the practice being exempted from regulatory control.. The staff's view is that an-assessment of the components of total collective dose must be made to satisfy NEPA requirements. However, in performing cost-benefit analysis, several alternative approaches can allow truncations in collective dose or weighting factors for the monetary value of averted dose to be applied. Truncations in time and space have been used in the past and could continue to be used in situations where a O choice between alternatives is not further clarified by. unbounded collective dose assessments. An individual dose cutoff could also be considered on the basis that small-individual doses-(e.g., less than 0.1 mrem per year) represent an insignificant risk and that the 1 collective impact from the summation of these individual l exposures'will be very-small. Finally, varying monetary values.could be assigned to components of collective dose, e.g., $1000 per person-rem for collective dose composed of individual doses in excess of 1 mrem per year and $100 per person-rem for individual doses less than l this value. At this time, the staff believes that the -use of any.or combinations of the above approaches could be appropriate depending on the practice under consideration for exemption. The ACNW supports the concept of a graduated monetary weighting of the individual dose contributions to collective dose. In developing the proposed policy statement, the staff (1) the existing policy on consumer the gemstone decision, and (3)productsthe general considered (30 FR 36921, (2) statement of policy and procedures concerning petitions submitted pursuant to 9 2.802 for disposal of radioactive waste streams below regulatory concern. Regarding the existing consumer product policy, the proposed exemption policy is generally consistent with the 1966 policy statement on "Use of Byproduct Material and Source Material - Products Intended for Use by the General Public (Consumer

~ ~ g 'e c + Q ] k The Commissioners 5 [ p Products)." On the gemstone issue, the Comission decision that the practice was justified could, under this policy, be - based on a determination of marginal benefit and on a simple demonstration that individual and collective doses involved-with gemstone distribution and use are small. Based on the anticipated ability of the. defined practice (i.e., radioactive, gemstone distribution to and use by the general public) to i meet the 10 mrem per year total effective dose equivalent and the collective dose criteria, the exemption would be allowed 4 under this policy.- The Comission's statement on policy and procedures concerning petitions for disposal of radioactive waste below regulatory concern provided fourteen decision criteria which, if satisfactorily met, would demonstrate that'the petition should be suitable for expedited Commission action. The staff believes that'the emphasis placed on definition of " practice" within the proposed policy, and the individual and collective dose values selected.as criteria below which ALARA cost-benefit analysis may be waived, envelop the applicable-issues addressed by the fourteen criteria. With regard to other exemption regulations, the proposed policy states that the Comission will evaluate whether there are existing exemption criteria for which modifications would be . beneficial. The staff has evaluated the proposed policy with regaro to emerging national and international guidance on the subject. It should be noted that the 10 mrem individual dose criterion for simple demonstration of justification of practice and ALARA is somewhat higher than values.being considered outside 4 the llnited States. The IAEA has recommended a value of 1 mrem, The Atomic Energy _ Control Board of Canada is consider-ing a 5 mrem value under certain conditions, and the National Radiological Protection Board has recomended a 0.5 mrem value. It is expected that the U.S. Environmental Protection Agency will propose 4 mrem as a BRC level for land disposal of low level radioactive waste. Furthermore, in assessing i collective dose for cost-benefit analysis, the use of an I, individual dose cutoff has not been adopted internationally or I nationally. These issues will be highlighted at the NRC-organized international meeting on exemptions scheduled for October 1988. i The staff has, as indicated areviously, identified policy L areas in which consensus wit 1 the ACNW has been reached. provides the staff's response to other ACNW cements. The Comission should note that the proposed policy recognizes l that, if a national policy on exemptions from regulatory lt il

q f.- l-i 1 O The Commissioners 6 l ( 1 control is to be effective, Agreement States will play an l important. implementation role. Accordingly, the-proposed-policy calls for coordination with the States to expedite the process by which the rulemakings codifying exemption policy can be made matters of compatability with the States. Coordination: The Office of General Counsel has reviewed the proposed policy statement and has no legal. objection. ~ Recommendations: That the Commission: 1. Approve discussion of the proposed policy statement and options at the NRC-organized, October 17-19, 1988 Workshop on Rules for Exemption from Regulatory Control. 2. ' Approve staff efforts to subsequently finalize the proposed policy statement for publication in the Federal Register. The FRN would include a request for public comment on the basic foundations and key elements of the proposed policy. p, [ -f jug. <!c $ s ' tor StM l'oGr.' Executive DiPector for Operations

Enclosures:

l 1. Staff Requirements Memo 2. Draf t Policy Statement 3. Options for Numerical Values 4 Major Policy Alternatives

5.. Response to Specific Commission l

Questions l-6. Response to ACNW Comments [ L t - f l l l l~

a 7 Commissioners comments or consent should be~provided directly to the Office of the Secretary by c.o.b., Monday, September 26, 1988. Commission Staff Office comments, if any, should be submitted to the Commissioners NLT Monday, September 19, 1988, with an information copy to the Office of the Secretary. If the paper is of such a nature that it requires additional time for analytical review and comment, the Commissioners and the Secretariat should be apprised of when comments may be expected. DISTRIBUTION: Commissioners OGC l OI I OIA GPA REGIONAL OFFICES EDO i ACRS ACNW l ASLBP ASLAP j SECY ) i i l

.a q 't U#D# IN RESPONSE, PLEASE /ge,g\\*; REFER 70: M880314 UNIT CO $T ATES - 8. NUCL E AR' R EGULATORY COMMISSION 4 yp was mcion.o c.nsst ACTION - Beckjord. RES / March-30, 1988 Cys: Stello Taylor - g,pect or TH Rehm sacastaav Thompson NMSS Murley, NRR Murray. OGC SNeuder. RES'- MEMORANDUM FOR: Victor Stello, Jr. Executive Director for O tions FROM: Samuel J. Chilk, Secreta

SUBJECT:

STAFF REQUIREMENTS - BRI CFJE 4G ON THE STATUS ~ OF EFFORTS TO DEVELOP A DE MINIMIS POLICY, 2:00 1 P.M., MONDAY, MARCH 14, 1988, COMMISSIONERS' CONFERENCE ROOM, D.C. OFFICE (OPEN TO PUBLIC ATTENDANCE) The Commission was briefed by the staff on the status of efforts:to develop a Commission policy statement identifying a level of radiation risk or dose below which government regu-F lation would be-limited or unwarranted. The-Commission requested and the staff agreed to submit for o Commission can' sideration options for a Commission policy which establishes,a generic number for: exposures that are below j regulatory conciern. The paper should disen== +he uncersminiime in our data' bane regarding radiation risk and should include. the supporting-scientific and legal rationale for all proposals.. consideration should be given to the assumptions made in- -f establishing de facto BRC levels that appear in current NRC regulations. The. staff should also. discuss the approach ~for implementing sucn a nummer wr mu AsapAe sources or licensed activities wnicn coes not require iustification'by individual licensees. This options paper is to be-actea upon by the i l Commission prior to the staff meeting with international groups K4t.y t/i//g' l' on this subject. . C Lsh. Mp# (RES) 4SEC'#-Suspense---91W8 84 p' 0/ L 30) Commissioner'Bernthal requested the staff to provide him the bases and~ analytical techniques used by other agencies (e.g., EPA and FDA) in' developing a de minimis policy / regulation on-l toxic waste (e.g., did they use a linear hypothesis?). -( EDO4-(RES) (SECY Suspense: 4/29/88) Red Off. EDOg, s v % \\' l C:,tc Tim.__ - I W--

./: 2-Subsequent to the meeting, Commissioners Roberts and Bernthal requested that the staff's options paper should explicitly ) identify the undergirding assumptions and projected ris.k estimates, both societal and individual, used in the establish-ment of'such BRC limits appearing in NRC regulations. Specific points staff should address include: In 1981, the Commission revised Part 20 to permit disposal ofscintillationcocktai}4and agimal. carcasses containing trace concentrations of C or H without regard for their radioactivity. Also, specified curie amounts of both isotopes may be released annually into the sewerage system. Some regulatory control remains (e.g. record-keeping and limitation on use of contaminated carcasses). but in effect, once released to the environment'NRC exerts no further control, thereby setting a floor to ALARA for these specific isotopes and applications.. What calcu-lations of societal and/or individual risk were employed in determination of these exempted levels? Were the models and assumptions the same as those used to arrive at tables of exempt quantities elsewhere in NRC regs? Staff raises the question on page 4 of SECY-88-69-as to .whether a definition of " radioactive" can be usefully established. Not mentioned in Enclosure 2 is the fact that DOT regulations do precisely that (4 9 CFR 173. 403).

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For purposes of transportation, a radioactive material'is defined as a material having a specific activity of 2 nci/g on-greater. This definition is incorporated.in NRC regulations (10 CFR 71.10) not as a definition per se,.but as an exempt quantity under NRC transportation' regulations.. What-is the origin of this 2 nCi/g limit? Given that a . limit on total specific activity limit applies to any and all isotopes,what assumptions were made regarding chemical form, pathways to the environment, critical organs, etc.? For purposes of enforcing the many de facto BRC limits which exist in NRC regulation what explicit allowance is made for instrument and measurement uncertainties? (Recall, that the Commission only just recently promulgated require-ments for some measure of QA for dosimetry processors.) Acceptable levels of residual surface contamination are designed in Reg. Guide 1.86. Facilities with surface contamination levels below those specified may be released for unrestricted use. How many and what types of licensee facilities have been decommissioned using these criteria? p

g 4 I 't e 3_ o The Commission was recen'tly made' aware of some of.the history behind the licensing of 3M static eliminator 1 devices. The general license for these devices allowed up' ~to S nCi of removal activity without any action being required.on the part of the general licensees.'.Do similar provisions exist in other licenses?- What is the. origin of l l the 5.nCi allowable leakage rate? What assumptions of risk were made to justify this number?- cc:- Chairman Zech Commissioner Roberts Commissioner Bernthal Commissioner Carr Commissioner Rogers OGC (H Street) T GPA .PDR - Advance DCS - 016 Phillips .(.9 g e e 9 e. 9 - f e

h.,. .. = + e y, i i DRAFT Proposed Comission Policy on Exemptions from Regulatory Control for s Practices Whose Public Health and Safety Impacts are Below Regulatory Concern 1. INTRODUCTION AND PURPOSE Over the last several years, the Comission has become increasingly aware of the need to provide a general policy on the appropriate criteria for release of radioactive materials from regulatory control. To address this need, the Comission is expanding upon its existing policy-for protection of the public from radiation, currently expressed in existing regulations (Title 10, Code of Federal Regulations) and policy statements (30 FR 3462, Use of Byproduct Material and Source Material, dated March 16, 1965;-47 FR 57446, Licensing Requirements foy Land Disposal of Radioactive Waste, dated December 27, 1982; and 51 FR 30839, General. Statement of Policy and Procedures Concerning Petitions Pursuant to 9 2.802 for Disposal of Radioactive Waste Streams Below' Regulatory Concern, dated August 29,1986). The expansion includes the' provision of an explicit policy on the exemption from regulatory control of practices whose public health and safety impacts are below regulatory concern. A practice is defined in this policy as an activity or a set or combination of -a number of similar sets of coordinated and continuing activities aimed at a given purpose which involve the potential for radiation exposure. Under this policy, the definition of " practice" is a critical feature which will assure -that the formulation of exemptions from regulatory control will not allow deliberate dilution of material or fractionation of a practice for the purpose of circumventing controls that would otherwise be applicable. l The purpose of this policy statement is to establish the basis upon which the ( Comission may initiate the development of appropriate regulations or make l. licensing decisions to exempt from regulatory control persons who receive, \\; l l 1 l-

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_f: o r possess, use, _ transfer, own, or acquire certain radioactive material. This policy is directed principally toward rulemaking activities, but may be applied -to license amendments or license applications involving the release of licensed radioactive material either to the environment or to persons _who would be exempt from Comission regulations. The concept of regulatory exemptions is not new. For example, in 1960 and 1970, the Comission promulgated tables of exempt quantities and concentrations for radioactive material which a person, under certain circumstances, could receive, possess, use, transfer, own, or acquire without a requirement for a license (25 FR 7875 and 35 FR 6427). Other exemptions allowing distribution of + consumer products or other devices to the general public, or allowing releases of radioactive material to the environment, have been embodied in the Comission's regulations for some time. More recently, the Low Level Radioactive Waste Policy Amendments Act of 1985 directed the Comission to develop standards and procedures for expeditious handling of petitions to exempt from regulation the disposal of slightly contaminated radioactive waste material that the Comission . determined to be below regulatory concern. The Comission responded to this l legislation by issuing a policy statement in August 1986 (51 FR 30839). That statement contajned criteria which, if satisfactorily addressed in a petition-for rulemaking, would allow the Comission to act expeditiously in proposing appropriate regulatory relief on a " practice-specific" basis consistent with' the merits of.the petition. ~ f The Comission believes that these " practice-specific" exemptions should be encompassed within a broader NRC policy which defines levels of radiation risk below which specified practices would not require NRC regulation based on public health and safety interests. For such exempted practices, the Comission's regulatory involvement could therefore be essentially limited to licensing, inspection, and compliance activities associated with the transfer of the radioactive material from a controlled to an exempt status. The Comission recognizes that, if a national policy on exemptions from regulatory control is to be effective, Agreement States will play an important implementation role.- In -the past,- States-have been encouraging -findtngs that certain wastes are below regulatory concern and the Comission believes that i L 2

y t' States will support an expansion of these views to all practices involving p t exempt distribution or release of radioactive material. The Comission intends y that rulemakings codifying regulatory control exemptions will be made a matter "~ of compatibility for Agreement States. Consequently, any rulemakings that evolve from this policy will be coordinated with the States. ( II. RADIATION PROTECTION-PRINCIPLES j The Commission subscribes to three fundamental principles of radiation protection in formulating its policies and regulations to protect workers and the public from the harmful effects of radiation. They are (1) justification of the practice, which requires that there be some net benefit resulting from ? the use of radiation or radioactive materials, (2) dose limits, which define the upper boundary of adequate protection for a member of the public which a should not be exceeded in the conduct of nuclear activities, and (3) ALARA, which requires that' radiation dose be as low as is reasonably achievable, economic and social factors being taken into account. The term, ALARA, is an-acronym for As low As is Reasonably Achievable, For the' purpose,.of establishing the stochastic (i.e., statistical) health risk associated with its radiation protection policies, the Commission also subscribes to a linear quadratic relationship between. dose and effect which is -linear over the dose range for which this policy applies. 'The hypothesis upon which the model is based assumes that the risk of radiation induced' effects (principally E L cancer) is linearly proportional to dose, no matter how small the dose might I be. The coefficient used in the model is on the order of 2x10" risk of fatal cancer per rem of radiation dose received by an individual. In subscribing to this model, the Comission recognizes that it is a model based upon data l collected at relatively high doses and dose rates which is then extrapolated y L .to the low dose and dose rate region where there are no statistically reliable L epidemiological data available. Although alternative hypotheses have been l proposed and reevaluations of the data base at higher doses continue, no signif-icant change is anticipated in the generally accepted linear model and its numerical coefficient. It is therefore the Comission's view that the use of the linear model provides a reasonable basis for developing exemption policy. l 3 s

,, I i 4 -The risk of death to.'an individua.1, as calculated using the linear model', is shown in Table 1 for various defined levels of individual dose. The lifetime ~ risk.is based upon the further assumption that the exposure level is the same j + for each year of a 70 year lifetime. Table 1 Incremental Incremental Lifetime Risk from Annual Dose Annual Risk Continuino Annual Dose l '1x10',f 100 mrem 2 x 10 10 mrem. 2 x 10 7 ' 1 x 10 -5 1. mrem 2 x 10 ~ 1 x 10 -8 -6 0.1 mrem 2 x 10 ' 1 x 10 1 Unless otherwise indicated, the expression of dose in mrem refers to the Total-Effective Dose Equivalent. This term is the sum of the deep dose equivalent for sources external to the body and the committed-effective dose equivalent for sources-internal to the body. 2 Risk coefficient of 2 x 10'4 per rem based upon publications of the

ICRP, The Commission recognizes that it is impossible to measure risk to individuals

.or populations directly, and, that in most situations, it is impractical to f measure annual. doses to_ individuals at the low levels implied by exemption decisions. Typically, radioisotope concentrations or radiatio'n levels from the - material to be exempted are the actual measurements that can be made, and doses are then estimated by exposure pathway analysis combined with other types of ~ assumptions related to the ways-in which people might become exposed. Under such conditions, conservative assumptions are frequently used in modeling so that the actual dose is on the low side of the calculated dose. The Commission believes that this is the appropriate approach to be taken when determining if ' an exemption from regulatory controls is warranted. In the application of the fundamental principles of radiation protection, collective dose provides a useful way to express the impact (i.e., detriments) of a nuclear activity on the health of the population subject to radiation exposure. Collective dose is the sum of the individual doses resulting from a practice or source of radiation exposure. By assigning collective dose a monetary value, it can be used in cost-benefit and other quantitative analysis 4

7- =- u e l techniques. 'It is therefore an important factor-to consider in balancing benefits and_ societal-detriments for practice justification and ALARA determinations, .III. APPLICATION'0F RADIATION PROTECTION PRINCIPLES TO EXEMPTIONS FROM REGULATORY CONTROL The following sets forth guidelines about how the Coninission will apply the fundamental pr_inciples of radiation protection in consideration of. practices rhich are proposed to be exempt from regulatory control. These practices, if approved, would result in products containing low levels of radioactive material being distributed to the general public and radioactive effluents and solid waste being released to areas of the publically-accessible environment. o Justification - Exposures resulting from any practice should be justified; thus, even at trivial levels of dose, the practice considered for exemption should be justified. As lower levels of radiation exposure are projected, lower levels of benefit will be needed for practice -justification. However, in establishing its policies the Commission will continue to prohibit certain practices for which there is no reasonable justification. o Dose Limits - Individual doses from practices exempted under this policy. ~ should not be allowed to exceed 100 mrem per year. This is the dose limit for members of the public specified in the final revision of 10 CFR Part 20, Standards for Protection Against Radiation. The dose limits in the final revision of 10 CFR Part 20 apply to all sources of radiation exposure under a licensee's control (natural background and medical exposures are excluded), o ALARA - The ALARA principle generally applies to determining dose levels -below which exemptions may be granted on a cost-benefit basis.

However, it is the purpose of this policy to establish criteria for individual and collective dose which would delineate achievement of ALARA without cost-benefit analysis.

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[ w1 + i <j-e Although it'is possible to reasonably project what the dose will be from a practice, and then take this information into account in controlling regulated practices so that the dose limits are not exceeded, exemptions imply some degree of loss of control. The Commission believes that a key consideration in establishing a policy for exemptions, and subsequently in specific rulemaking i or licensing decisions, is the possibility that individuals may experience radiation exposure approaching the limiting values through the cumulative effects of more than one practice, even though the exposures from each practice are only small fractions of the limit. By appropriate choices of exemption criteria and through its evaluations of specific exemption proposals in i i implementing the policy, the Commission intends to assure that it is unlikely that any individual will experience exposures which exceed the 100 mrem limit. IV. PRINCIPLES OF EXEMPTION Once a practice is established as justified, i.e., there is a positive net benefit to the introduction or use of radioactive material, the decision of whether or not the entire practice, or some defined subset of the practice, is a candidate for' exemption from regulatory control hinges on the general question of wheper or not application or continuation of regulatory controls are necessary and cost-effective in reducing dose. To determine if exemption is appropriate, the Commission mu::t determine if one of the following - conditions is met: 1. The application or continuation of regulatory controls on the practice does not result in any significant reduction in the individual or collective dose received by individuals within the critical group and by the exposed population or; 2. The costs of the regulatory controls that could be imposed to reduce the individual and collective dose are not balanced by the commen-surate reduction in risk that could be realized. For purposes of implementing its policy, the Comission recognizes that only under unusual circumstances would practices which cause radiation exposures approaching the 100 mrem limit be considered as candidates for exemption. The 6

+ v Commission will consider such circumstances on a case _ specific basis using the. general principles outlined in this policy statement. However, as the doses and-' attendant risks to members of the exposed population decrease, the need for-regulatory controls' decreases and the analysis needed to support a proposal for-exemption can reasonably be-somewhat simplified. At a sufficiently low level. of individual-risk, decisions regarding exemptions (i.e., whether ALARA has been achieved) can be reduced to an evaluation of whether the overall public risk is sufficiently small. The Commission therefore proposes that two numerical criteria should be established in defin_ing the region where ALARA has been achieved. They are (a) a criterion for the maximum individual annual dose reasonably expected to be received as a result of the practice and (b) the collective dose to the exposed population. In combination, these criteria are chosen to as3ure that, for a given exempted practice, no individual will be exposed to a significant risk and that the population as a whole does not suffer a significant impact. I If the individual doses from a practice under consideration for exemption are sufficiently small, the attendant risks will be small compared with other societal risks The Comission believes that annual individual fatality risks 0 below approximately 10 are of little concern to most members of society. ' Providing for some margin below this level, the Comission proposes 10 mrem a's: the level of annual individual exposure below which ALARA_can be demonstrated on the basis-that collective dose is also sufficiently small. The incremental annual individual cancer fatality risk associated with an exposure level of 10 mrem per year is about 2x10 as indicated in Table I and of the order of 0.1 percent of the overall risk of cancer death. . The collective dose criterion proposed is 100 person-rem per year per practice. Adoption of this value provides assurance that the number of individual exposures at or near 10 mrem will be no more than a few thousand people and that for the exempt practices to which it is applied a fatality among the exposed population would be very unlikely. If the collective dose and individual dose fall below these levels, then the risk from a justified practice is considered to be ALARA without further 7

F ' I analysis. The Comission stresses that adoption of the individual and l collective dose criteria should not be construed as a decision that doses below these criteria are necessary before a~ practice can be exempted, while doses above_the criteria would preclude exemptions. On the contrary, the criteria simply represent a range of risk which the Comission believes is sufficiently small compared to other individual and societal risks that a cost-benefit analysis.is not required in order to make a decision regarding the acceptability of an exemption. Practices not meeting these criteria may be granted exemptions on a case-by-case basis in accordance with the principles j embodied within.this policy. To further emphasize the Comission's recognition that a rigid limitation on collective base is inappropriate, it notes.that for some practices, such as use of smoke detectors, appreciable benefits can only be attained through extensive utilization and, hence, with a comensurate-collective dose. The Comission is aware that existing regulations of the Environmental Protection Agency establish criteria more restrictive than exemptions which could otherwise be granted under this proposed policy. With regard to its own regulations, the Comission will evaluate whether there are exemption criteria i embodied therein for which modification, according to the principles of this policy, would be beneficial. V. EXCLUSIONS FROM EXEMPTIONS There are some types of practices involving radiation or radioactive materials which are, prima facie, socially unacceptable regardless of how trivial the resulting dose might be and, therefore, should be excluded from exemption. Excluded practices would include, but not be limited to, the intentional introduction of radioactive material into toys,and products intended for ingestion, inhalation or direct application to the skin (such as cosmetics). Exclusions would also include the purposeful and frivolous distribution or release of radioactive materials where there are clear, economical alternatives to such use and the practice is not justified because there are no unique benefits from using the radioactive materials. 8

VI. PROPOSALS FOR EXEMPTION A proposal for exemption must provide 'a basis upon which the Comission can determine if the basic conditions described above have been satisfied. In general, this-means that the proposal should address the individual and .. collective doses resulting from the expected activities under the exemption. including the uses of the radioactive materials, the pathways of exposure, the levels'of activity, and the methods and constraints for assuring that the assumptions used to define a practice remain appropriate as the radioactive-materials move from regulatory control to an exempt status. If a proposal for exemption results in a rule containing generic requirements. - a person applying to utilize the exemption would not need to address justification or ALARA. The Comission decision on such proposals will be based on the licensee's meeting the conditions specified in the rule. The i promulgation of the rule would, under these circumstances, constitute a finding that the exempted practice is justified, and that ALARA considerations have been dealt with. This approach is consistent with past practice, e.g., consumer product rules in 10 CFR Part 30. If, after a p'ractice is determined to be justified and a simple assessment indicates that the likely consequences of exemption are individual and collec-tive doses approximately equal to or less than the criteria values, there would be high likelihood that the application would be accepted by the Comission. In evaluating proposals for exemption under this policy, the projected exposures to different components of the exposed population will be considered with regard to the potential that some individuals may receive doses near the 100 mrem limit-when doses from other practices are also taken into consideration. If exposures from multiple practices can occur which are significantly beyond the individual dose criterion (10 mrem), the exemption will not be granted without further analysis. As experience is gained, this policy and its implementation will be reevaluated with regard to this issue to assure that the exposures to thepublich::ltIremainwellbelow100 mrem. > dh m e :< L.G t /. av7 9

L. ^.. In' addition to considerations of expected activities and pathways, the Commission recognizes that consideration must also be given to the potential for accidents and misuse of the radioactive materials involved in the practice. A proposal for exemption of a defined practice must therefore also address the. potentials for accidents or misuse, and the consequences of these exceptional conditions in terms of individual and collective dose. VII. CALCULATION AND USE OF COLLECTIVE DOSE ASSESSMENT The collective dose can serve as both a measure of the impact (i.e., detriment) { of a practice on the exposed population and a mechanism for assessing the benefits of regulatory constraints on the practice being exempted from regulatory control. In the latter case, a monetary value can be assigned to the collective dose so that cost-benefit assessments can be made with respect to the usefulness of controls or con:traints on a practice to further reduce-collective dose, l The Commission believes the assessment of the components of total collective dose must be made to satisfy National Environmental Policy Act requirements. However, when used for cost-benefit analyses or for evaluation against the ] collective dose criterion-proposed in this policy, several alternative approaches can allow truncations or weighting factors to be applied, ror example, the. collective dose is often used to discriminate.between alternatives ' or' options. The collective dose in such cases should be calculated to the 3 point where a choice between options is clear. Complying with this requirement l will often allow the truncation of the collective dose assessment in time j and/or space. Also, large uncertainties associated with dose, particularly at very low dose or dose rates may render certain components of the assessment l non-useful in the comparison of alternatives. Furthermore, an individual dose cutoff could also be considered on the basis that the summation of small I individual doses (e.g., less than 0.1 mrem per year) represent an insignificant societal risk or that the collective dose attributed to these small doses is i very small in comparison to the remaining collective dose from the exempted l practice. Finally, varying monetary values could be assigned to components of l collective dose, e.g., $1000 per person-rem for collective dose composed of 10 i

, m.; ..e.it r 4 ( individual-doses in excess of I' mrem per year and $100'per person-rem for lower J individualidoses. The Comission believes that the use of one or more-of the q 'above approaches could be appropriate depending on the practice under consider- .ation for exemption from regulatory control. i -VIII. VERIFICATION OF EXEMPTION CONDITIONS -s j The Commission believes that the implementation of an exemption under this broad policy guidance must be accompanied by a suitable program to monitor and verify that the basic considerations under which an exemption was issued remain valid. In most cases, the products or materials comprising an exempted practice will move from regulatory control to the exempt status under a defined set of conditions and criteria. The monitoring and verification program must therefore be capable of providing the Commission with the appropriate assurance that the conditions for the exemption remain. valid, and that they are being observed. The Comission will detennine compliance with the specific conditions of an exemption through its established licensing and inspection program and will, from time to time, conduct studies as appropriate to assess the impact of an exempted practice or combinations of exempted practices. j 11

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ENCLOSURE 3 Options Fo? Numerical Values Within The Proposed Exemption Policy The proposed exemption policy is broadly based on the principle that, if adequate public protection is provided, exemptions for a particular practice or class of practices can be based on justification of practice and a supporting cost benefit analysis or determination. Numerical values are proposed for individel ar.d collective dese which, because of the small risks involved, woLid allow the mt.rits of excmpting 3 p"actiet from rsgulatory :rntrol to be 4 b6std on simple analyses or judgments. Tnece (Nmptions would traolve prettices in which individual dosts to the critita r population group would De m limited to less than 10 mrem per year d the collective dose would not exceed 100 person-rem per year. 1 4 I (1) The 10 mrem per year individual cose ialce t The 10 mrem per year individual dose value together with the 100 person-rem collective dose criterion provides the basis for exemption decisions based on simple demonstrations of justification of practice and 3 ALARA. Sclection of this individual dose value is based on the premise. that an individual risk approximating 10 per year, for a practice providing some societal benefit, is a level of risk considered small by many regulatory bodies and one which is widely held to be of little concern to the individual. The 10 mrem per year value is one-tenth (1/10) of the 100 mrem per fear dose limit applicable to members of the public in the draft final major revision to 10 CFR Part 20. This value can also be compared to other exposures received by members of the public as indicated in Table 1. l l 1 Dose when used in this enclosure refers to total effective dose l equivalent. i }

I r l I TheNationalCouncilonRadiationProtectionandMeasurements(NCRP) { recomends 1 mrem per year as a negligible individual risk level (NIRL) [ which, if resulting.from a specific practice, could be dismissed from regulatory consideration. However, they recognize that if an individual would be exposed to as many as ten sources or practices in a year, the use I of N!RL could result in the annual dismissal of up to 10 mrem per year for an individual. The International Atomic Energy Agency (IAEA) and several national regulatory bodies have made similar (e.g., de minimis) determina-tions at individual dose values ranging from 0.5 to 5 mrem per year. Alternative values below the 10 mrem per year individual dose level could l be chosen to be combined with the collective dose criterion. A 1 mrem per year value would translate into en individual risk at the low end of the range of values commonly identified by nyeral regulatory bodies as being trivial to individuals. Somewhat lower, the National Radiological Protecticu Board (NRpB) has recommanded a 0.5 mrem per year value as a de I minimis individual dese rate when associated with exposure from a sir.gle i oractice. The Atomic Energy Control Board of Canada (AECB) is considering adopting 5 mrem per. year as a de minimis dose rate for exempting specific sources and practices from licensing. This annual value of dose is stated as corresponding to the upper end of the range of risks considered insignif-icant by individuals in their personal decision-making. However, the AECB

• states that this value-will be used to decide upon exemptions provided that the radiological impact is localized and the potential for exposures of large populations is small.

Further, the AECB will take into account in exempting any new practice, the dose received by individuals within the critical groap from all license-exempt practices. Another alternative to the 10 mrem per year value would be 4 mrem per year, a limiting value used by the EPA in drinking water standards, and being proposed by EPA as a BRC level for land disposal of low level radioactive waste. The 4 mrem per year value was discarded principally because its selection could imply a degree of precision inconsistent with the value-judgment aspects of the proposed policyv Since the existing Comission statement of policy and procedures regarding petitions for BRC 2

L, ), I i waste disposal refers to a range of doses (i.e., a few millirem per ye0r), the significance of choosing between a 10 or 4 mrem per year value is { diminished from the technical standpoint.- It should be recognized, i however, that existing Commission regulations and those of the EPA may be more restrictive regarding potential exemptions for specific practices. (2) The 100 person-rem per year collective dose value The 100 person rem collective dose value together with the individual dose criterion, provides the basis for exemption decisions based on simple demonstrations of justification of practice and ALARA. This criterion plays a prom-inent role by limiting the number of hypothetical ir.d'vidual i exposures at 10 mrem per year to ten thousand people ne r 0.004 percent of j the 'J.$. popda tion. At a -esult, the collective dose Uiterion serves as a anatraint which would reduce the thence of a specific indiviceal being i exposed to multiple exempt practices at dose otes aporneching the 10 mrem per yea" salue. Using the linesr rnlatiorship between des 2 and effect, this collective dose criterion would provide high assurc.nce that, for the exempt practices to which it is applied, no statistical fatalities would be predicted per year of practice. The 100 person rem value has been used internationally to represent a de minimis collective dose on the basis that there would be no potential for reducing collective dose below this value at reasonable regulatory cost. An alternative collective dose value of 500 person-rem could be selected. This value would retain the advantages of the 100 person rem value (with the exception that a non-order-of-magnitude value could imply a certainty of knowledge not commensurate with the value judgments incorporated in the proposedpolicy). The 500 person-rem value would be consistent, although not truly comparable, with the Comission's societal risk safety goal if the societal risk goal was applied to the average 57 thousand people estimated (based on 1979 data) to be within 10 miles of nuclear power plants. 3 4 o--- r-

P i TABLE 1 COMPARISON OF INDIVIDUAL DOSE VALUES TO REFERENCE EXPOSURES RECEIVED BY MEMBERS OF THE PUBLIC i Fraction or Multiple of Reference Value DOSE OF EQUIVALENT VALUES 10 mrem /yr, 1 mrem /yr 0.1 mrem /yr Natural Background (excluding radon) - 100 mrem /yr 0.1 0.01 0.001 Cosmic Radiation (U.S. Average) - 23 mrem /yr 0.4 0.04 0.004 U.S. Variation in Cosmic Radiation ~ - Washington,D.C. vs Denver, CO - 24 mrem /yr (26-50)

0. 5 0.05 0.005 Terrestrial Gamma Radiation

- 28 arem/yr 0.4 0.04 0.004 U.S. Variation in Terrestrial Gamma Radiation - Atlantic / Gulf Coast vs. Rockies East Slope ~ 47 mrem /yr (16-63) 0.25 0.025 0.0025 One Hour of Air Travel at 39,000 feet - Enhanced Cosmic Exposure ~ 0.5 mrem 20 2 0.2 4

5 a l i ENCLOSURE 4 MAJOR POLICY CONSIDERATIONS CONSIDERATION 1 - THE ROLE FOR " JUSTIFICATION OF PRACTICE" IN THE COMMISSION'S PROPOSED EXEMPTION POLICY In the SRM of March 30, 1988, the Commission requested that the staff should "... discuss the approach for implementing such a (generic BRC] number for multiple sources or licensed activities which does not require justification by individual licenses." Justification or practice nas been a basic principle of radiatiun protection octh nationally and internationtily. The principle, rec.ommended by tne ICRP, has been reflected in existing Commission regulations and is included in basic radiation protection documents such as IAEA Safety Series No. 9. The staff has-attempted to respond to the Commission's directive in two ways. First, the staff is proposing a regulatory exemption policy with individual.and collective dose criteria which define a basis for exemptions in which only simple demonstrations of justification and ALARA would be required. A practice would be considered a strong candidate for exemption if the individual . exposures to members of the critical population group are less than a value of about 10 mrem per year and the collective dose to the general public is less than about 100 person-rem per year. This decision process recognizes that the small individual and collective risks associated with certain practices should require little balancing in terms of compensating benefits. Second, the staff has provided, in the policy statement, an explicit recognition that rulemakings would constitute a finding by the Commission that the exempted practice was justified. Therefore, a person applying to utilize the exemption would not need to address justification or ALARA. 1 y 9 ens-.

e On the issue of multiple sources, the staff's recommendation that all practices r be justified precludes a plethora of unjustified practices which would contribute to the problem of exposures to mult.iple sources. If a practice involves limited individual and collective risk as defined, the determination on whether the specific practice should be exempt from regulatory control would only hinge on the proper assessment of the individual exposures within the critical population group and the collective exposure of the general public. If the Commission should decide that " justification of practice" is not required for certain activities, based solely on the fact that the consequent doses are celow certain levels, the staff believes that the Commission is essentially opting for definition of a de minimis or negligible risk policy. The staff and the ACR$ Subcommittee on Nuclear Waste (now the ACNW) are both in i agreement with the Commission's decision (made in the March 30, 1988 Staff Requirements Memorandum) to focus a proposed commission exemption policy on below regulatory concern rather then de.ninimis considerations. A BRC policy is much more likely to have e positive 'mpact in assuring reasonable and proper expendituro of resources to control small radiological risks. Since a BRC l policy implies are tcceptable trade off between benefits and cocts of regulatory control, the staff believes that the cor: cept of justification of practice must be retained. sithough the rigor used to evaluate justification can be reduced, to allow simple or straight-forward judgments if radiological risks are sufficiently small. CONSIDERATION 2 - SPECIFICATION OF PRACTICES EXCLUDED FROM THE EXEMPTION POLICY The proposed policy includes a section which describes practices which would be excluded from the exemption policy. Excluded practices would include, but not be limited to, radioactive material introduction into toys and products intended for ingestion, inhalation, or direct application to the skin (such as cosmetics). The staff believes that these classes of practice would be considered socially unacceptable regardless of how trivial the resulting dose might be. 2

The need to identify practices excluded from exemption policy is closely tied to the role ultimately defined by the Commission for the " justification of practice" principle. If the Commission should decide to reduce the role played l by justification of practice" as currently described in the proposed policy, the staff believes the need for identification of excluded practices would be accentuated. As currently proposed, the section of the policy describing l excluded practices provides guidance on the types of practices for which the Commission believes that use of radioactive material is not justified. CONSIDERATION 3 - CALCULATION AND USE OF COLLECTIVE DOSE ASSESSMENTS The collective dose can serve as both a measure of the impact of a practice on the exposed population and a mechanism for assessing the benefits of any regulatory constraints on the practice being exempted from regulatory control. The assessment or description of the components of total collective dose must be made to satisfy NEPA requirements. However, in performing cost-benefit analyses, several approaches can allow truncation or weighting factors to be applied. Use of these truncations or weighting factors can be supported if the 1 purpose of the collective dose assessment is to discriminate between optiors or if large uncertair. ties are associstad with dose assessments, perticularly at very low deses'or dose rates, so that assessment of certain cbmponents of collective dose serves little purpose. Three approaches are described below which could be acceptable for use in decision-making regarding practices which' are candidates for exemption from regulatory control. Individual Dose Cutoff in Collective Dose Calculations In the background discussion accompanying the publication of the proposed 10 CFR Part 20 revision (51 FR 1113) dated January 9,1986, application of a-de minimis individual dose level cutoff was considered which would be applicable to the calculation of collective dose. The proposed application of this de minimis concept was recognized as having an influence on the evaluation of situations where very large numbers of people could be subjected to very low doses. This provision was excluded from the final Part 20 rule in deference to the formulation of the policy proposed in this statement. 3 u .m

In essence, the individual dose cutoff approach would disregard extremely low annual individual doses (<0.1 mrem per year) from the collective dose impacts associated with a practice being considered for exemption from regulatory control. The recommended value for the individual dose cutoff in this approach ( is 0.1 mrem per year which represents an individual lifetime risk of about 10 This risk level is used by other Federal and State agencies to make judgements on the risk of chemical carcinogens both in the environment and as residual contamination in food products. In these situations, substantial numbers of people can be exposed at these individual risk levels. Typically. l no actions are taken when individual lifetime risk is less than 10, even when significant populations could be affected. Exposures of about 50 million people would have to occur at the 0.1 mrem per year level before use of the linear hypothesis would predict a societal health effect. Where collective doses to a population are evaluated, the acceptability of the associated potential risks can also be compared to the sum of the potential risks from background radiation experienced by the same population over the same time I interval. Consequently, even though some practices could result in very small but finite doses to very large numbers of people, the comparative collective risk to which tnese people are routinely subjected is also very substantial and proportional to the number of people considered, e It should be pointed out that, although the NCRP supports the cutoff concept, neither the ICRP nor NRPB has accepted the use of an individual dose cutoff fo collective dose calculations. The NRC's Office of General Counsel has noted that use of a collective dose cutoff in the mill tailings decision would have reduced the calculated benefits of the regulations. Assignment of Varying Monetary Values to Collective Dose Componeng In assigning values to collective dose, a value of $1,000 per person-rem has been used previously by the Commission. It was first used in 10 CFR Part 50, Appendix I for determination of ALARA. However, it has been recognized that the more universal application of the $1,000 per person-rem, when applied to summation of doses representing individual risks less than 10' to 10 per year, for purposes of determining ALARA, can in some instances result in undue expenditure of resources which might better be applied to other uses. 4

n } e i Numerous regulatory bodies have determined tnat a dose on the order of l 1-10 mrem per year represents a range of risk in which individuals are unlikely I to take any actions to further reduce their risk. This 10 mrem per year level i serves, in the proposed Commission Policy Statement, as a criterion, together with a collective Jose criterion, for determining if a simple analysis or a more detailed ent.ysis is required for approval of an exemption. This level may also be an appropriate value at which to reduce the valuation applied to collective doses for purposes of ALARA or cost-benefit analysis. For example, collective dose assessments for purposes of exemption policy may be assigned monetary values as follows: { $1,000 per person-rem for collective dose composed of individual doses in excess of 1 mrem per year. $100 per person-rem for collective dose composed of individual doses at or below 1 mrem per year. t t The valuation of collective dose at $100 per person-rem for individual doses at or below 1 mrem per year reflects the belief that the individual risk associated with this small level of dose does not warrant the same level of consideration is larger doses. This is not meant to imply, however, that these doses can be dismissed entirely. In keeping with the linear hypothesis for, radiation protection p'lanning, these small levels of dose should be considered when establishing that the overall detriment of the practice is adequately balanced by the benefits of the practice. Truncations of Dose in Time and Space Truncations of collective dose in either time or space have been used in the past. These truncations could continue to be used in situations where a choice between alternatives is not clarified by unbounded collective dose assessments. l For example, collective dose may be truncated to reflect the limitations of an l engineering design under consideration (several hundred years) or collective dose from effluents may be limited to populations within a specified distance of the releasing facility. l 0 i

Responses to Commission Questions Regardino Basis for Prior BRC Actions { and Discussion of Uncertainty in Oose-Response Coefficients ? Question: l In 1981, the Commission revised Part 20 to permit disposal of scintillation I 14 cocktails and animal carcasses containing trace concentrations of C or 8H without regard for their radioactivity. Also, specified curie amounts of both isotopes may be released annually into the sewerage system. Some regulatory ~ control remains (e.g. recordkeeping and limitation on use of contaminated carcasses) but in effect, once released to the environment; NRC exerts no further control, thereby setting a floor to ALARA for these specific isotopes and applications. What calculations of societal and/or individual risk were employed in determination of these exempted levels? Were the models and assumptions the same as those used to arrive at tables of exempt quantities elsewhere inJRC regs? Answer The analysis provided with SECY-81-77. Final Amendments to 10 CFR Part 20 on Disposal of Certain H-3 and C-14 Wastes, included' calculations of individual and societal risks associated with the disposal of trace concentrations of H-3 and C-14 without regard to their radioactivity. In the preamble to that final rule, estimates were provided that total quantities of radioactive material affected by the rule would be 28 Ci of H-3 and 6 Ci of C-14 annually. The unrestricted disposal of these materials (except as to their non radioactive hazardous properties) could result in a maximum radiation dose to exposed individuals of less than 1 millirem per year, and less than 1 societal health effect over the next 1000 generations. These impacts result from one years practice under the exemption at present levels of use.. Doses were derived using incineration as the' disposal method, Regulatory Guide 1

t = 1.109 as the basis for breathing rate assumptions and for inhalation dose conversion factors, and ORNL-4992, A Methodology for Calculating Radiation Doses from Radioactivity Released to the Environment, for dose calculational methods and associated conversion factors. Doses associated with disposal of H-3 and C-14 using the sanitary sewage system were calculated to be much lower than doses from incineration. The exempt quantities rule was issued much earlier, in the 1960's. The modeling and criteria used in that case were much simpler; if an exempt Quantity was inhaled or ingested, the critical organ would not receive a dose commitment in excess of 500 mrem. t P 2 g

t \\ Question: For purposes of enforcing the many de facto BRC limits, what explicit allowance I is made for instrument and measurement uncertainties? i i f Answer-r There are instrument and measurement uncertainties associated with manufac-turing consumer products, and with NRC activities aimed at assuring compliance with regulatory restrictions placed on the manufacturer. These uncertainties, [ as applied to the manufacture of products for txempt distribution, are not so l different from measurement uncertainties applicable to other activities involving use or release of radioactivity. Applicants for licenses to manuf acture products containing byproduct material for exempt distribution are selectively required to submit " quality control procedures to be followed in the fabrication of production 1 cts of the product and the quality control standards that the product will de required to meet" (10 CFR 32.26(b)(15)). With e reasonable quality assurance program, measurement and instrument inaccuracies are not a major source of uncertainty in the dose analyses for exempt products. For decommissioning and some waste forms, difficulties in fully assessing the contamination present unique problems which must be carefully considered in rulemaking or licensing actions in these areas. Assessing residual radioactivity for the purposes of license temination involves the use of historical information to "look for" potential areas of 4 significant contamination and application of statistical analyses to estimate doses since it is impractical to sample every inch of a facility or site where there is potential for contamination. The keeping of appropriate records to assist in decommissioning planning and in termination survey design has been addressed in the recently published decommissioning rule (June 27, 1988; 53FR24018). The verification process is being considered in an ongoing Battelle PNL contract which is providing input to the development of a policy or rulemaking on residual radioactivity criteria for license termination. In 07/13/88 1

i i;. 4 addition, some waste streams, such as dry active waste, present a particularly difficult assessment problem which must be considered.in any waste stream specific BRC waste rulemaking, I t l' f i L h I i i l t i I l s h e a 6 e i s P h 07/13/88 2 4 -s,

t f t i Question: [ What is the origin of the 00T value of 2 nanocuries per gram used to defing radioactive material for purposes of transportation? Answert The Department of Transportation regulations in Title 49 of the Code of Federal Regulations contain a definition of " radioactive material" which excludes materials having a specific activity not greater than 0.002 microcuries per { gram. This definition was taken from the Transportation Safety Act of 1974 i (P.L. 93-633), Section 108, where its applicability was limited to I transportation of radioactive materials by passenger aircraft. Prior to that, the definition has had broad applicability and for many years has been included in the Regulations for the Safe Transport of Radioactive Material (Safety Series No. 6) of the International Atomic Energy Agency (IAEA). i r The IAEA explanation (IAEA Safety Series No. 7) of the reason for its definition of " radioactive mater',al" including a lower cutoff of 70kBq/kg (0.002 pei/g) is "to avoid bringing within the s;:0pe of the regulations many substances, often naturally occurring, which contain insignificant amounts of radioactivity, and which, if transported, pose no significant hazard. As to the origin of the limit, the French CEA, following its 1068 examination of the IAEA Transport regulations, offered the following explanation to the European Atomic Energy Community-Euratom: Working downwards, there necessarily comes a time when the specific activity of a material is so low that it no longer presents any external or internal radiation hazards; this limit has been fixed conventionally at 0.002 pCi/g. It is a limit relating to each gram of material and not a limit relating to the nuclide itself contained in this material. Below and up to this limit, the Regulations do not apply. j This value probably originated as follows: Plutonium 239 was selected as being the most representative nuclide commonly met in transport. The MPC 07/13/88 3

^~ 4 1 t 4 i (cir) was, according to the ICRP recommendations at that time, i -6 x 10'I pCi/m for continuous 168 hour per week exposure. Taking 3 3 ~4 3 0.3 mg/m,'i.e. 3 x 10 9/m, as the dust content of polluted air, the ' radioactive concentration of this air which could reach the above MPC was i a maximum of ~7 = 0.002 pCi/g. 6 x 10 3 x 10'4 Today's equivalent of this number, taking the internationally recommended derived Gir concentration (DAC) for Pu-239 of 2x10'1 Bq/m (5x10 pCi/m ) for 3 -6 3 occupational exposure at 40 hr/wk and converting for continuous exposure of the general public would be 0.0004 pC1/g. i l It is not immediately clear if this limit on the definition of radioactive material derived through consideration of the inhalation pathway would have applicability to tha wide range of ' practices for which "below regulatory concern" determinations could justify exemptions from regulatory contrel. h 1

t 07/13/88 4

u,. Question: Acceptable levels of residual surface contamination are designated in Reg. Guide 1.86. Facilities with surface contamination levels below those specified may be released for unrestricted use. How many and what types of licensee faciiities have been decommissioned using these criteria? Answer: The " Acceptable levels of residual surface contamination" of Regulatory Guide 1.86 have been used since June of 1974 for releases of reactor facilities to unrestricted access following decommissioning. The same set of numbers was used in the decommissioning of reactors prior to issuance of Regulatory Guide 1.86 and since at least 1970. At that time these numbers were specified in a draf t position from the Division of Materials Licensing dated April 22, 1970 (Attachment 1). Since April of 1970 NRR has terminated reactor licenses for 31 non power reactors (including critical facilities) under the above surface contamination criteria. Since 1981, NRR hea added a requirement for specific gamma emitting radionuclides (Cc-60, Eu-152, and Cs-137) that are not surface contamination. These radionuclides must be removed such that the radiation level from them is.* .less than 5 microroentgens per hour above r.atural background as mecsured at one meter from the surface. Alternatively, since 1982, a licensee is permitted to demonstrate that reasonable occupancy of an area would be such that the potential exposure from these gamma esitting radionuclides would be less than H 10 mrem per year. Examples of these criteria are provided in Attachment 2. 1 l 7/8/88 ~. J

.~ j The following summarizes the status, as of March 8, 1988, of reactors t .(including critical facilities) that have been shutdown with continued license I t or decommissioned: i Type of Licensee Facility Number Shutdown or Decommissioned l Power, Test, and Nuclear Ship Reactors 17 t Research Reactors and Critical Facilities with Continued Possession License 8 Dismantled Research' Reactors 33 Dismantled Critical Facilities 17 t Decommissioned Demonstration Nuclear l [ Power Plants (DOE Owned) 4 The criteria ganerally used by NHSS fer releasing facilitiet /or unrestricted l o use are contained ir. two documents. Thtse documeats are (5) Guidelines for i Decontamination of FaciMtf es and Equipwnt Prior to Release 19r Unrestricted., Material", (Attachment 3) and (2) Dispctal or Cniite Storage of Residual Thorium or Uranium (Either as Naturai Ores or Without Daughtars Present) from l Past Operations Providec to the Consission in SECY-81476 dated October 5, 1981. The guidelines i.ve been used to release on the order of 20 facilities i or buildings that processed natural U or Th, Pu, enriched U or depleted U. There are also on the crder of 10 facilities or buildings where release is l pending the confirmatory survey or the removal of residual contamination. The L criteria in the second document has been used to release land or soil on the order of 10 times. In addition, over 19 requests for release using those criteria are pending. Occasionally, site specific criteria are established. These numbers do not include facilities that may have been released by the regions. 7/8/88 h

.p 1 l. i. 'ATTACC;C;Tj. Li. l 1 ss j l ~ i t, t \\ CUID2.I!33 70:1 DCCO:iT/J32;ATIC:107 TACILITIT.15 A:.T EQUIF12;.T ~ FP.IcR % REXt.5E FOR UIN.ICT::D V55 - cR ht? cut:ATIO:1 Ol* LICESts TCR DYPROD*,'CT, SCURCK, 'OR SPECII.L i;UCLT).". I'.M~4RU*. U. S. Atcre.ic Er.+rgy Cr.,.v.iscion y Wivision of l'acials Licensins .. Washington, U, C. Ic0%) e i d APRIL 22,1970 t ..,3 4.et a. .t ( t. t.

.] .?* } The instructions in-this Cuide in ponjunctica with Tables I and II specify the radionctivity ated'. radiation, er.posure rate if e.its which should be used in accomplishina. the decont4.mination and survey of . sufacus of prettises and equip ent prior to abandonsant or release l for unrestricted use. She limits in Tchles I and II do not apply to premises. eg tip:cznt, or sets.p containing induced radioactivity , for which the radiolosical considerations pertinent to their use , any bee difrerent. The release of such facilities or items from regulatory control will,be concidered en a case-by ekse basis. 1. The licensee r.hn11 mar.c a rgasonable effort to eliminate realdual contumination. l Radioactivity on equipr.cnt or surfaces shall not be covered '2,

• by. paint, plating, or, other covering materici unless con.

t tanination icvelt, as detemir.ed by a survey and doeur.ented, are below the limits specified in Tables I or II prior to applying the coverinc. A reasonable effort must be made to minimise the contamination prior 1.o use of any covering. The radioactivity on the interior surfaces of pipes, drain I.. 3 3 lines, or ductvorh shall be deteminte by an.hinc measurer.ents at au traps, and other e.;propriate access pointu, provided that contr.'ainution at if,esu ice,ations is likely to be repre. sentat.tvo of contaminctien en the interior of the pins, druin C -li,aes, or ductvorh. Surfet ers of praniaes. aqui;c:ent, er scrcp k.'. which are likely to be ec.edsate.1 but are of sun site, conatf action, or locetter. cs to ar.he the surface int.ecesrible for prposes of seeaurrment shan be presvred to be contr.alented a f An extoss of thei 1.imits. S. Upon rashnest, the Cor.r.issf.on may autMrise a 1:,ren:ec to reli quish k. possession or control of premiset, esgipmen% or scrap having surfaces contaminated vith sattfiols in excess et' tM 11.zita Tnis smuy include, but vould not be limiteti to, special speelfied. circumstances such as rasing of buildinc.s transfer of premises h ~ to another orcanisation continuinf. Work vith radioactive r.sterials, or conversion of facilitics to a long-term storage or standby '*j-status. Such recruests must: Provide detailed, specific inferr.ation describing the premises, a. equipment or scrap, radioactive contaminants, and the nature, extent, and degree of residuti surface contamination. b. Provide a detailed health and safety analysis which reflects that the residual amounts of ar.terials on surface areas, .--[ together with other consideraticas such as prospective use of the premisas,' equip =ent or scrap, are unlikely to result in an unreasenchic risk to the henith and safety of the public. C.h ' y ~

F l l . ;t. j e l ) 3 Prior to release of preresses for unrestricted use, the licensee shall i make a cospreheracive radiation survey which estr.blishes that conte.. inntion is within the 11sdts spectried in Tabics I or II. A copy of the survey report shall be filed 4*ith the. Director, Division of j Hateric1s Licensing, 01/5C, t'Lshington, D. C. 20545, and also the Director of the Regional Division of Co. pliance Cffice ha' ting ...l I jurisdiction. The report should be filed at least 30 days prict to %..e piknned date of abandoutent. The survey report shall: a. Identify the premises., b. Show that vensoimble effort has becu made to alininate residual ' conta'nination. c. Decerabc.2e unope of %c survey and Ceneral procedurce followed. d. Staste %e findJncs of %c surwey Jn units specified in the 4 instruution. Tollowing r.tview of the report, the M;C vill consider visiting the facilitics to confirm the survey. 6 i i' i y ....s C e ,s

( 9 .e e stmract ciMAM1F.ATION IIVliS.y - zn - * ~2 i .l 7 TABLE 11 l TARLE 1 -} i 150TOFE TOTAL KDEMABLE TOTAL RI' MOVABLE U-nat, U-235, U-238, 10,000 dpa e/100 cm l 1,000 dpa o/100 co l Aver-w.e@) 2 2 l 2 5,000 dys d100 c2 1,000 dps ellC0 ca Th-nat, Th-232, and cssociated. decay products

!px!==

2 L i 25,000 dps :/100 cm i I ' her isotopes which decay 1,000 dpa e/200 cm. 100 dra e/100 cm Avera;-[ 2 2 U t 2 500 dro -1100 cm 100.dpa e/100 h olpha estesion or by Mu! un 2 cponteneous fisston 2.590 dpa d100 co l

Beto-Cassa emitters (iso-0.4 ared/hr at. I es 1,00') dpa!hr/100 co gy,r,r,W 2

2 U.2 crad/hr at 1 ca(5). 1,000dpa54/100 topes with decay modes i .Wxicu m cther than siphe asission j g g 1.0 r.::d/hr at 1 en or spontaneous fission) I 4 '{ For exanple, if all beta-gecas readings were less than 0.4 nrad/hr at I ca, tither Table 1 or Table II asy be used. J (1) Table I could be used; 1ut if the awfourt readin;; vere 0.8 stad/hr, material could be released u : der Table II pro-r l viding the average was less ti,an 0.2 ored/hr. t l Where surface contamination by beth alpha of b :ta-sm czitting isotopes exists, the linits estetlished for sipha (2) i cnd beta-ga-=s emitting isotopes shall septy independently. l per einote) neans the rate of raission by radioactive material as l h) As used in this table, dpa (disintegretient detereined by correcting the co sn2r pen utr.vte ebserved by en appropriate detector med cc.:st rate zeter for back-l j grosad', efficiency, and ger,cetric factert ssaccleted.ith the instrumentstion. i 2 (4) The aeount of renovable radioactive matet tal per 100 rn of surface area shall be determined by wiping that area, I i with dry filter or sof t ab.orbent pcper eM with th:: rpplication ef nederate pressure, and essessing the anevnt of r5dioactive meterial on the wipe with an appropriate instrtraent of knes:n.cfficicacy. In deteruininy, removable con-i taninntion on objects of lesser surface arco, the pertinent 1:vels chall be reduced propertionally, cod the eatire surface shall be wiped. - i Measured through not more thar. 7 r.1111 reas per sqca o centimeter of tetel absorber. t l (5) (r.) ..,...,..r.~ ~ '*11 conta:In. int chall not he ever. :fd ever :rore than 13 sgsare ce&r- ~ ~ '-ets or ics::: t

i [ [ L t ENCLOSURE 6 3 i Staff Response to ACNW Coments ( L L On July 21, 1988, the Advisory Comittee on Nuclear Waste reviewed an earlier L: draft of the Comission paper with the proposed policy statement and other enclosures. The Comittee's coments were transmitted to the Comission on j August 9, 1988 and several areas of consensus have been identified in the body of the Comission paper, i The ACNW has stated that exemptions should be granted for practices whose annual and lifetime individual risks are less than 10*7 and 10-5, respectively, and that, under -these conditions, any restrfetion on collective dase is i ennecesstr3 The steff, however, veiteves that both the 10 crari per year %dividual ese (f acreased froru i mitta ner.yesr in the previous drif t pelicy) and the 100 persorierem co'lective dose are necessary to define e threshold belcw which ALARA etst-benefit analysis may be waived. The ACNW (and the ttaff's proposed policy) supports the possibility c' grenting exemptions for practices not a.ecting the aforementioned criteria based on cost-benefit analysis (which implies a role for collective dose). Thus, if a threshold is to be defined below which ALARA cost-benefit analysis may be waived, cutoffs on both individual and collective dose appear logical. The staff would also point out that other Federal and State agency decisions on cleanup of carcingenic chemicals infer a role for collective dose even down to implied de minimis risk levels (10-6 to 10~7 lifetime risk). 1 4

~ ] e, f i The ACNW has also recommended that the policy statement should require all past NRC exemptions to be reviewed for compatibility with the proposed policy. The staff could support this position and could develop a plan and estimate the resources needed for such an undertaking. The staff believes that comitting i i to such an undertaking in the policy statement is premature. Similarly, the ACNW suggests that prior methodologies for performing cost-benefit analyses should be carefully reexamined. Again the staff could support this position but believes the issue does not need to be resolved prior to issuance of the policy statement or discussion of the issues at the forthcoming international workshop. i Finally, the staff believes that it has logically presented a policy addressing the entire complex issue of exemptions from regulatory contrt,1. The staff recognizes that its recommendation goes somewhat beyond the Comission's desire for a single generic 7xmber for exposures that are below regulatory concerr., However, the staf' belitves that a policy along the lines proposed (including i definition of individual and collective dose criteria for simple demonstration of "jwMf1 cation of practice" and ALARA) will have a more meaningful impact or the granting of exe g tions which will assure public health and safaty whi'<e fostering a more logical expenditure of resources to control le n is of risk below basic standards of adequacy. 2

~ i.31.9,,1 n a sua,an.o.e.ne m f*") * ) A%4 4 t 'APR 21 1952 Docket No. 50-141 Dr. Roland A. Finston Of rector Health Physics and Biosafety Stanford University 67 Encina Hall stanford, California 94305

Dear Dr.' Finston:

By letter dated March 17,1981, we provided radiation criterta' forhelease , of the dismantled Stanford Research Reactor to unrestricted access. That criteria specified Reg. Guide 1.86 for surface contamination and 5 micro ' Rea per, hour at one meter for reactor generated, gamma emitting isotopes. since March 17. 1981, we have refined further our position with respect. to roles,se criteria and have deterstned that' radiation from samma emitting . isotopes is also acceptable if 'the potential exposure to individuals is 1.ess than 10 mrem per year with reasonable occupancy assumptions. If you , are greater than 5 micro Rem 'per hour,from reactor generated isotopes that wish to.19stify gamma exposure rates , you should show that reasonable ' occupancy.of that area would be suffi,ciently less than 2000 hourf'per year, which would result in exposures of less than 10 mrem per year j Stacer

• I f.

j James P...M111fr. Chief l, f- / Stinderdization and Sptfihl Projects Branch i Division of Licenst,ng i 9 i l l ( l i 4 i 0

p. J%* i utvi e w n i a s a.a 'g.. i a?.1 * ' NUCLEAR REGULATORY COMMISSION ' /N w'4 '- ~' ) wwwstow. o. c.nsis {- t] - March 17, 1981. 1 / ] _.\\' W...."f. Docket No. 50-141. *. w 1 3 Dr. Roland A. Finston i Director. Health Physics and Biosafety a 1 Stanford University ) 67 Encina Hall. Stanf.ord. California 94305

Dear.Dr. Finston:

1 By letters da,ted December 9.1977 and June 3,1980 you provided dat.a on " the residual activity at the dismantled Stanford Research Reactor. You .. further requested temination of reactor License No. R-60. l As discussed wi,th you, we h'a've now detennined the levels of r'adiation '.. that.would be acceptable for m1 ease of the stanford reactor facility to sarestricted acces's. Enclosure No'.1 provides that criteria. Enclosun 'lio. 2 (Regulatory Guide 1.86) is also provided.for your infomation. ~ ' .Thuttforri ve car, teminate License No. R-60 4 ten our indepeadent surveys . confirm thet yof have removed sufficient residual redhaetivity in meet E i the criterk of ~ Enclosure No.1. - ^ [- ' ty copy rf this letter to the NRC Region Y offica, we request that th?y - co piete a confirmatoty survey wnen you notify the WRC that your fecility l is ir, enmp11ance with Enclosure No.1 criteria. y l ine2rtly. r s J n E. Stolz Chief 0 rating Reacton B anch f4 vision of Licensi,ng inclosures: 1. Radiation Levels for Release to Unrestricted Access 2. Regulatory Guide 1.86 ec w/ enclosure 1 only: See next page

p l ,r - A-i t j RADIATION LEVELS FOR RELEASE DF REACTOR l . FACILITY TO UNRESTRICTED 4 ACCESS i Surface Centaminet' ion' Surfaces must be decontam nated to levels consistent with Table 1 of i Reg., Guide 1.86. i Raficact'ive Meterial Othe'r Then $9rface Contamination (Co 50. Eu 152.' Cr 137) to '60. Eu 152 and Cs 137 that any exist in concrete. components. structures. and soil'aust be removed such that, the rtdistion levg] fr m these isotopes is less than SpR/hr above natural background's as measured at one meter from sur).ce.

• Genertl She subey proce.dures acceptable to the F.RC must be used. J i

J l a

3) Radiation from naturtil.y' occurring radioisotopes as measured,it a comparable

'uncontarinated structure or exterior soil surface. I l i + ,r, e....- -,-,.--,,-.,..,.nn.-- ...-..,a,

m ) j s A rrown ew 3 1 1 1 i i \\ GUIDELINES FOR DECONTAMINATION OF FACILITIES AND EQU!PMENT PRIOR TO RELEASE FOR UNRESTRICTED USE l OR TERMINATION OF LICENSES FOR BYPRODUCT, SOUP.CE, j i DR SPECIAL NUCLEAR MATERIAL ) j l 4 i ^ d a i U.S. Nuclear Regulatory Conmission 01viston of Industrin1 and Medical Nuclear $6fety Washington, DC 20555 August 1987 e 1 \\

l j 3 i The instructions in this guide, in conjunction with Table 1, specify the i ndionuclides and radiation exposure rate limits which should be used in i decontamination and survey of surfaces or premises and equipment prior to abandonment or release for unrestricted use. The limits in Table 1 do not apply to premises, equipment or scrap containing induced radioactivity for I which the radiological considerations pertinent to their use may be different. J The release of such facilities or items from regulatory control is considered on a case-by-case basis. ) 1. The licensee shall make a reasonable effort to eliminate residual contamination. Radioactivity on equipment or surfaces shall not be covered bplating,orothercov 2. p as deternined by a survey and documented, are below the limits specified o in Table 1 prior to the application of the covering. A reasonable effort must be made to minimize the cordamination prior to use of any covering:, 3. The radioactivity on the inteeter surftces of pipes, drain linwst er e der.twork shall be determined by s.aking MessgevMr'ts Lt all trapc, &nd other sopropriate access points, provided that contamlrstier et thesp Iocations is likely to tHe representetive of centcP.ination on the intWr I of the ripes, train limpt. or ductwork. Surfp es of triettes, equipotet, or senp wh'ith ste Ine *y to be e3nteminhtea but tre of such site, coa.struction or locaticn as to Ete the surface inacassible far pur c.f meesrement thall be preM(4 to be centsteinated in excess of the kc$es o imit). ] 4 ] 4. Upon request, the Cosmission mey authorize a licensen to relit <quish possessic;1 or control of premisas, ecuiement, or s: rap hsving surfaces ^ s containinated with materials in excess of the limits specified. TMs my include, but would not be limited to, special cirensstances sum 65 nring of buildings, transfer of precises te another organization continuing wort with radioactive materials, or conversion of facilities to a long-tern storage or standby states. Such requests must: s. Provide detailed, specific information describing the premises, equipment or scrap, radioactive contaminants, and the nature, extent, ) and degree of residual surface contamination, l b. Provide a detailed health and safety analysis which reflects that the residual amounts of materials on surface areas, together with other considerations such as prospective use of the premises, equipment, or scrap, are unlikely to result in an unreasonable risk to the health and i safety of the public.

• +ee--

+,,,-w y-+,m# -g-g _, + -g-y.,- y. ---,y.

l .= q. ~: dh' s 5. Prior to release of premises for unrestricted use, the licensee shall a make a comprehensive radiation survey which establishes that contamination. is within the limits specified in Table 1. A copy of the survey report i shall be filed with the Division of Industrial and Medical Nuclear Safety. U. S. Nuclear, Regulatory Commission. Washington, DC 20555, and also the Admiristrator of the NRC Regional Office having jurisdiction. The report should be filed at least 30 days prior to the planned date of abandenrent. The survey report shall: a. Identify the premises. 4 b.* Show that reasoneble effort has been made to eliminate residual-contamination. .c. Describe the scope of the survey and general procedures followed. d. State the rindings of the survey in units specified in the instruction. Followirg rev'iew of-the report, the NRC will consider visiting the facilities to confirm the survey. 9 e + t

.N b 5 .f ^ .g TABLE 1 4 ACCEPTABLE SURFACE CONTAflINATION LEvtLS NUCLIGE5a ~ AVERREEbcf fWullfeggb d f ret 90VA0tEbef 4 0-met. 1f-235. 3-230. and 2 2 asseclated decay products 5.000 4 e e/100 cm 15.000 dpa./100 cm 1.000 den./100 car Transerentcs. Ra-226. Ra-220 i l Th-230, th-228. Pe-231 ~ ISO 4s(100 ce! 300 dpm/100 cm2 20 dre/100 cm2 "Ac-227. I-125. 1-129 j t Th-nat. Th-232. Sr-90 l Sa-223. Ra-224. 3-232. I-126 1980.4 e/100 ce! 3000 dpe/100 col 200 dpm/100 cm2 I-131. I-133 ~ Deta-garwe emitters (necIldes i clth decay modes other than t 2 1000 dra sy/100 cm2 i cipha emissten or spontaneous 5000 dpa ty/100 ou 15.000 dpm 01/100 cm f!ssion) except $r-90 and i cthers noted above. - l aWhere surface contaminetten by both alpha-and beta-gesse-emitting nacIldes entsts, the lletts established for alphe-sad beta-ganne-emittiny l nacildes should apply independently. 1 6 s csed in this table, dpa (distategrettens per etnote) means the rate of entssten by redleective metertal as determined by correcting the A counts per ofnete observed by an appropriate detector for background, efficiency. and geometric factort associated with the instrumentation. l Celesserements of average contaminent should not be averaged over more than I square meter. For objects of less surface area. the everage i shomid be derived for each such object. dihe mentame contaminetten level applies to an evne of not more then 100 cm2, l CThe amount of' removable redtoactive meterial per 100 aut of surface area should be determined by wlptog that eree with dry filter er soft thstrbent paper. applying moderate pressere, and essesslag the amount of redteactive meterial en the wipe with an appropriate lastrument of known efficiency. When removable contaminetten en objects of less surface area is determined. the pertinent levels should be reduced proportionally and the entire surface should be wiped. fihe cverage and mentmas redtetten levels essectated with surface contaminetten resulttag from beta-gesse emitters should not enceed 0.2 erad/hr at I cm and 1.0 ared/hr at I cm. respectively messered through not more then F ellligrams per square centimeter of tsts1 absorber. e, ~ ~,:_ =

~ .-=-- - -. -.. i 4 I Ovestion: The Commission was recently made aware of some of the history behind the licensing of 3M static eliminator devices. The general license for these devices allowed up to 5 nCi of removal activity without_any action being required on the part of the general licensees. Do similer previsions exist in-other licenses? What is the origin of the 5 nCi allowable leakage rate? What assumptions of risk were made to justify this number? Answer: The 3M static eliminator devices are used under a general license provided in 131.5 of 10 CFR Part 31, " General Domestic Licenses for Byproduct Material.' Users of devices under that general license are required, with certain exceptions (set out in 531.5(c) (2)), to test the device for leakage of radioactive material at intervals no longer than six months or at such other l-intervals as are specified in the label on the device. Section 32.51(b) of 10. l CFR Part 32 " Specific Domestic Licenses to Manufacture or Transfer Certain Items Containing Byproduct Material " states the infomation which a manufacturer must submit in an application for approval of a label which provides a test interval greater than six months. If the test for leakage results in detection of 0.005 microcurie (5 nC1) or more removable radioactive material, the general licensee is required to imediately suspend operation of the device until it has been repaired or, shall dispose of the device by transfer to a specific licensee. The general licensee also must submit to the NRC a report containing a description of the event and the remedial action taken. l-Similar provisions for " leak testing," suspension of operations, remedial action, and reporting are routinely set out in specific licenses which authorize the use of licensed matarial in the fom of a sealed source. l

] . 7, z. Radiation safety programs for the use of licensed material as a sealed source-arel structured on the presumption that the radioactive material will not leak from the sealed source '.'and contaminate the environment or expose individuals f to radiation. The leak test is a check on the' validity of that presumption, ~ i The 5 nCi quantity is not an allowable leakage rate. It is a point at which l certain regulatory actions are to be taken. The detection of 5 nCi or more is-considered as a flag or signal that safety problems may exist. The 5 nC1 quantity has been used for about 30 to 35 years in the NRC (AEC) regulatory program and in industry standards. During early use, the 5 nCi quantity applied to alpha emitting radionuclides and a 50 nC1 quantity applied .to beta-gama emitters. A primary consideration in early use of these quantities was the general availability and use of instruments which could l measure the quantities. In about 1960, for administrative convenience in the regulatory program and with better instruments available, use of the 50 nCi quantity was largely discontinued and a single quantity, 5 nCi, has since oeen used. g -{ The 5 nCi quantity, which serves as an initiator for further actions, historically has not been justified on specific assumptions of risk. It has generally been considered a sufficiently small quantity that, by itself, L presents very low levels of radiation but is readily measured. It is not used in the regulatory program or by industry as an allowable leakage rate. Further, although terwed a " leak test " the usual test performed by users of sealed sources and devices containing sealed sources is a ' contamination test" and a positive indication does not always indicate leakage. A positive indication does show a need for further evaluation. L 1

l 7, 1 Question: What are the uncertainties in the estimates of the biological effects of ionizing radiation? Answer: The principal reference used by NRC to estimate the biological effects of low-level ionizing radiation is the_1980 Report of the Committee on the_ Biological Effects of lonizing Radiation of the National Academy of Sciences entitled, "The Effects on Populations of Exposure to Low Levels of Ionizing Radiation" (BEIR III). BEIR !!!, however, did not provide a precise set of health risk estimators for low levels of ionizing radiation, but rather presented a range of acceptable health risk estimators for both somatic (cancer) and genetic health effects. The range of values for radiation-induced. cancer was based on available data from high doses to human popuhtions. Various mathematical methods of extrapolation from this high dose data were then used to estimate the probable health effects, at low doses. The BEIR III Committee cautioned that the values from the models were " based on incomplete data and involve a large degree .of uncertainty, especially in the low-dose region." It also stated that " estimates of risk at low doses depend more on what is assumed about the mathematical form of the dose-response function than on the data themselves" and that "the Committee does not know whether dose rates of gamma or x-rays (low LET) of about 100 mrads/yr are detrimental to man." In estimating *.he somatic health effects, the $EIR III report utilized epidemiological data obtained from stadies of survivors of f w

~ . p f.* y

l

+ Hiroshima and Nagasaki and, to a lesser extent, other irradiated populations..The variations in risk estimates were due to factors other than just uncertainties in the Japanese and other epidemiological data bases. As noted above, most excess cancers have l been observed following relatively large doses delivered'at high dose ' rates. Moreover, the observation time of the exposed populations does not yet extend through the lifetimes of the irradiated individuals. Therefore, assumptions must be made about how' . observations at high doses should be applied at low doses and low dose rates for radiation of a given type (LET) and how risks from radiation might vary long 6f ter the' time.of exposure. The BEIR III report examined three dose response. functions in detail: _(1) linear, in which effects are directly proportional to dose at all doses; (2) linear-quadratic, in which effects are very nearly propoYtional to dose at very low doses and proportional to the square of the dose at high doses; and (3) quadratic, in which the risk varies as the' square of the iose at all dose levels. However, in i view of the results of preliminary analyses based on dose assessment of' Hiroshima and Nagasaki survivors, the quadratic model is not being considered as viable at this time. All mathematical functions assume l [ that there is no threshold dose below which there is no excess health risk. For low levels of low LET radiations, the BEIR III recommended the use of a linear-quadratic dose response function. To estimate the risk of radiation exposure beyond the years of l~ L observations, either a relative risk or an absolute risk projection 1 l 2 1

. g.. /. : g a I 4 t model (or suitable variations) must be used. The relative risk projection model projects the currently observed percentage increase in cancer risk per unit dose.into future years. An absolute risk model projects the average observed number of excess cancers per unit dose into the future years at risk. Because the baseline rate of cancer incidence rises dramatically with age,.the relative risk + projection model predicts a larger number of radiation induced cancers in an aging population for years beyond the periods of observation; consequently, the average lifetime risk calculated: according to the relative risk model is higher. ~ The BEIR Consnittee did not specify which projection model is the appropriate choice for most radiogenic cancers. Based on sensitivity studies regarding this choice risk estimates derived using different models could differ by a factor of about 3. When such variations are combined with the effect of different choices for the dose response function (iie., linear vs. linear quadratic) the risk. estimates.as indicated in BEIR III range over a factor of about 6. Because of a smaller data base, even greater uncertainties exist regarding risk estimates 'for individual body l-organs, in utero exposure, and high LET radiation, such as' fission 1 neutrons and alpha particles from radon decay products. There is L . also the question of describing the health risk in terms of morbidity or mortality. 1: l 3 l 1: L J.

h,.... # l V-l 9 Since publication of BEIR III, the. assessment of. doses received by Hiroshima and Nagasaki-~ survivors has been revised._ Initial analyses comparing results based on the old dosimetry system (T650) and on the revised dosimetry system (DS86) have been reported.1 ' These analyses make it clear that the effect on risk estimates will be strongly_ I 1 dependent on the assumed RBE for neutrons, which cannot be reliably estimated with the revised dosimetry, and on the shielding provided by the body _for specific organs of interest., t Complete assessment of these-recent data has not yet been reported and evaluated; however, based on preliminary evaluation by Preston and Pierce, it appears unlikely that the modified dosimetry will i increase risk estimates by more than a factor or two. Risk estimates for genetic effects are based on experimenta! animal data, since no suitable human data is available. BEIR III estimates 5 to 75 additional serious genetic disorders per million-live' births in the first generation following parental dose of 1 rem. Such a parental dose will, according to BEIR III estimates, result over'all time (i.e., over many future generations) in a total increase of 60 1 to 1,100 serious genetic disorders per million liveborn offsprings. The ranges of risk estimates underscore-the limited understanding of genetic effects of radiation on human populations. 1 Preston, D.L., and Pierce, D.A. (1987): The Effect of Changes in ~ Dosimetry on Cancer Mortality-Risk Estimates in the Atomic Bomb Survivors. RERE Technical Report 9-87 (Hiroshima City 730, Japan: Radiation Effects i Research Foundation). j 4 l

n-E pe<....o. x l U To summarize, the principal sources of uncertainty in estimates of ' risk from low levels of ionizing radiation are: 1. Assumption.of deleterious effects.at any dose, no matter how low' + i.e., no threshold. 1 2. Selection of mathematical model for extrapolation'from high . dose / dose rates (where effects have been statistically observed). to low dose / dose rates, i i

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Selection of temporal projection model beyond period of observation (absolute vs relative), s 4 Variability (geographical and temporal) in " normal" cancer rates v ~ upon which the relative risk estimates are based. '5. Uncertainties in doses received by' populations included in epidemiologic studies. 'l Currently the NAS~ has a revision of' BEIR III- (BEIR V) underway which is expected in early 1989. 'j 5 i -.. -}}