Radiological Criteria for License Termination of Uranium Recovery Facilities

NUCLEAR REGULATORY COMMISSION

10 CFR Part 40

RIN 3150-AD65

Radiological Criteria for License Termination of Uranium Recovery

Facilities

AGENCY: Nuclear Regulatory Commission.

ACTION: Final rule.

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SUMMARY: The U. S. Nuclear Regulatory Commission (NRC) is amending its

regulations regarding decommissioning of licensed thorium mills and

uranium recovery facilities to provide specific radiological criteria

for the decommissioning of lands and structures. This final rule uses

the existing soil radium standard to derive a dose criterion (benchmark

approach) for the cleanup of byproduct material other than radium in

soil and for the cleanup of surface activity on structures to be

released for unrestricted use. This final rule is intended to provide a

clear and consistent regulatory basis for determining the extent to

which lands and structures can be considered to be decommissioned.

EFFECTIVE DATE: This regulation becomes effective on June 11, 1999.

FOR FURTHER INFORMATION CONTACT: Frank Cardile, telephone: (301) 415-

6185; e-mail: [email protected]; or Elaine Brummett, telephone: (301) 415-

6606, e-mail: [email protected], Office of Nuclear Material Safety and

Safeguards, U.S. Nuclear Regulatory Commission, Washington, DC 20555-

0001.

SUPPLEMENTARY INFORMATION:

I. Introduction

II. Background

III. Summary of Public Comments and Responses to Comments

IV. Agreement State Compatibility

V. Final Environmental Assessment: Availability

VI. Paperwork Reduction Act Statement

VII. Regulatory Analysis

VIII. Regulatory Flexibility Certification

IX. Backfit Analysis

X. Small Business Regulatory Enforcement Fairness Act

XI. Criminal Penalties

I. Introduction

The NRC is amending its regulations regarding decommissioning of

licensed thorium mills and uranium recovery (UR) facilities

(conventional uranium mills and uranium extraction processes such as in

situ leach (ISL) facilities) to provide radiological criteria for the

decommissioning of lands and structures. These criteria apply to the

decommissioning of licensed UR facilities subject to the NRC's

jurisdiction and will also apply to thorium mills if any become

licensed in the future. The criteria apply to decommissioning of UR

facilities that operate through their normal lifetime and to those that

may be shut down prematurely. The NRC will apply these criteria in

determining the adequacy of remediation of residual radionuclides

resulting from the possession or use of byproduct material.1

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\1\ As defined in 10 CFR Part 40, byproduct material is the

tailings or wastes produced by the extraction of uranium or thorium

from any ore processed primarily for its source material content,

including discrete surface wastes resulting from uranium solution

extraction processes.

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The intent of this rulemaking is to provide a clear and consistent

regulatory basis for determining the extent to which lands and

structures at UR facilities must be remediated before decommissioning

of a site can be considered complete and the license terminated. The

NRC has previously applied site release criteria for decommissioning on

a site-specific basis using existing guidance for surface activity and

radionuclides other than radium in soil. The NRC believes that

inclusion of criteria in the regulations will result in more efficient

and consistent licensing actions related to site remediation

activities.

II. Background

On August 22, 1994 (59 FR 43200), the NRC published a proposed rule

to amend 10 CFR Part 20 of its regulations ``Standards for Protection

Against Radiation'' to include radiological criteria for license

termination as subpart E. The proposed rule applied to uranium mills

and other NRC-licensed facilities, but did not apply to mill tailings

or to soil radium cleanup at mills because they are regulated under 10

CFR Part 40, Appendix A.

On July 21, 1997 (62 FR 39058), the NRC published a final rule that

codified radiological criteria for license termination for NRC

licensees, but excluded UR facilities. The NRC excluded UR facilities

from the scope of the final cleanup rule to allow further consideration

of the issues unique to the decommissioning of these facilities. These

unique issues include the existing regulatory framework for UR

facilities and the nature of contamination at UR facilities, both of

which are discussed below.

Under the existing regulatory framework for UR facilities, the

Environmental Protection Agency (EPA) has the authority to set cleanup

standards for uranium and thorium mills and, based on that authority,

issued regulations in 40 CFR Part 192 that contain some decommissioning

criteria for these facilities. NRC's regulations in 10 CFR Part 40,

Appendix A, Criterion 6(6), conform to EPA's standards for radium in

soil. Appendix A also provides ground-water protection criteria.

Therefore, this rulemaking addresses only the radiological criteria

for decommissioning of lands and structures. The rule only applies to

those UR facilities that do not have an approved decommissioning plan

for buildings and soil when the rule becomes effective. The sites with

approved decommissioning plans may request an amendment to their

license to adopt the criteria of this rule after the revision to

Criterion 6(6) is promulgated.

The applicable cleanup standards for soil radium in 10 CFR Part 40,

Appendix A, Criterion 6(6), address the main contaminant at uranium

mills in the large areas where windblown contamination from the

tailings pile has occurred, and to a lesser extent, at ISLs in holding/

settling ponds and process or bleed solution spills. These standards

require that the concentration of radium (Ra-226 at UR facilities, Ra-

228 at thorium mills) not exceed the background level by more than 5

pCi/g (0.19 Bq/g) in the first 15 cm (6 inches) of soil and 15 pCi/g

(0.56 Bq/g) for every subsequent 15 cm (6 inch) layer. However, in

other mill and ISL site areas proximate to locations where radium

contamination exists (e.g., under/around the mill/process building, in

a yellow cake storage area, and under/around an ore crusher), uranium

(U-nat) is the radionuclide of concern. At least one mill site must

also address soil cleanup of thorium (Th-230, the parent of Ra-226, is

usually in approximate equilibrium (same activity concentration) with

Ra-226) because thorium is more mobile in the acidic milling solutions

and leaches farther into the ground than the radium under raffinate

ponds and heap leach pads. Because 10 CFR Part 40, Appendix A, does not

have cleanup standards for surface activity or for soil contamination

from radionuclides other than radium, NRC guidance documents have been

the source of cleanup criteria for residual uranium, thorium, and

building surface activity.

An additional difficulty for remediation of UR facilities is that

the residual radionuclides to be addressed in the site decommissioning

are also present in the surrounding background soil in elevated and

widely variable concentrations. Some mill sites even have uranium mine

pits and/or piles of

[[Page 17507]]

overburden soil containing low-grade ore on or adjacent to the areas to

be remediated. This complicates the determination of background values

and limits the ability of the licensee to distinguish residual

radioactivity from naturally occurring (in-situ) radioactivity.

To allow for consideration of these issues, the NRC also published,

on July 21, 1997 (62 FR 39093), a request for additional comments on

regulatory options for decommissioning of UR facilities. Included as

part of the request was a discussion of an option to codify a dose

objective for radionuclides other than radium (uranium and thorium) at

UR facilities consistent with the radium cleanup standard. Under this

approach, UR facilities would use the dose, excluding radon, from

radium at the cleanup standard in existing 10 CFR Part 40, Appendix A,

Criterion 6(6), as a benchmark for the cleanup of building surface

activity and radionuclides other than radium in soil. Commenters were

requested to provide input on options for decommissioning and,

specifically, on the benchmark approach.

Use of the benchmark approach would provide for a common dose

criterion across a UR site for those areas contaminated with radium and

for those areas contaminated with other radionuclides.

The radium dose benchmark approach would require UR licensees

subject to the rule to calculate the potential total effective dose

equivalent to the average member of the critical group for the site

that would result from the radium standard within 1000 years, based

upon site-specific parameters. These licensees would be required to

provide justification for the models and parameters selected in the

dose calculations. The dose from the 5 pCi/g (0.19 Bq/g) radium

standard would be applicable for most of the site contamination.

Licensees would then remediate the site such that the residual

radionuclides (byproduct material) remaining on the site that are

distinguishable from background would not result in a dose that is

greater than that which would result from the radium soil standard. The

radionuclides of concern are uranium and thorium, because it is assumed

that the progeny of Ra-226 are at acceptable levels when the radium

standard is achieved. Licensees would also be required to demonstrate

that doses were ``as low as is reasonably achievable'' (ALARA). In the

unlikely event that a site benchmark dose (before application of ALARA)

exceeds 100 mrem/yr (1 mSv/yr), the NRC staff would consult with the

Commission before approving such a benchmark dose.

III. Summary of Public Comments and Responses to Comments

Comments received on the 1994 proposed rule for 10 CFR Part 20

subpart E were summarized in NUREG/CR-6353 and in the final rule notice

(62 FR 39058, July 21, 1997). The eleven responses (nine commenters) to

the July 21, 1997, request for additional comments on radiological

criteria for UR facilities are addressed here.

A. Comments on Approach to the Criteria

One commenter indicated that the standards should be technically-

based, protective of human health, and based on a substantial fraction

of the 100 mrem/yr (1 mSv/yr) public dose limit. The use of dose-

objective standards was encouraged. Evaluation of radon and thoron

exposure was considered essential. This commenter also pointed out that

the benchmark approach would codify a different dose limit for each

facility.

The EPA commented that the soil radium standard of 5 pCi/g (0.19

Bq/g) is consistent with the minimally acceptable dose limit of 15

mrem/yr (0.15 mSv/yr) for the residential scenario, and that for other

land use scenarios, the cleanup standards are more stringent for Ra-

226, Ra-228, Th-232, and Th-230. The EPA also cautioned that a dose

limit for uranium cleanup should not exceed 15 mrem/yr (0.15 mSv/yr).

A third commenter stated that the proposed rule is not acceptable

because doses resulting from the benchmark approach could exceed 100

mrem/yr; NRC's existing guidance on cleanup of uranium, thorium, and

surface activity should be used to set the minimum requirements; the

expected dose from the radium standard should be clarified; the radon

dose should be included in demonstrating compliance; and the time frame

for dose modeling should be 10,000 years. The commenter also indicated

that the proposed approach seems to allow a total dose of twice the

radium dose; and that if more types of areas are to be included than

those indicated in the proposal, then the enlargement of scope would

require additional notice and review.

Six other commenters supported the Ra-226 benchmark dose approach

for cleanup of other radionuclides such as U-nat, Th-230, and Th-232.

These commenters indicated that the existing regulatory framework is

appropriate and provides for flexibility to allow optimum tailings

disposal on a site-specific basis. One of these commenters also pointed

out that uranium mill sites will be turned over to the custodial care

of the Department of Energy (DOE) or the State for long-term care,

effectively eliminating substantial portions of these sites from the

public exposure pathways. In addition, some of the vicinity properties

remediated with neighboring abandoned mills (under the DOE's's Uranium

Mill Tailings Remedial Action Project) have deposits of contamination

(Ra-226, Th-230, or U-nat) above the limits remaining under the

supplemental standards provisions of 40 CFR 192.21.

A. Response: The NRC agrees with the need to develop regulations

that are protective of public health and safety with regard to

decommissioning of UR facilities. NRC has previously addressed

considerations related to radioactivity and dose to the public, public

health aspects, fraction of the 100 mrem/yr (1 mSv/yr) dose, and the

rationale for excluding the radon dose in Sections A.2.2.1, A.2.2.2,

and F.6 of the July 21,1997, Federal Register notice (62 FR at 39060-64

and 39082) for the final rule for 10 CFR Part 20, subpart E; those

discussions remain applicable to this final rulemaking.

As discussed above, the UR facilities have large areas contaminated

with radium in soils where the existing radium standard is applied. The

NRC believes that it is important to promulgate cleanup standards for

other residual radionuclides that are consistent with the radium

cleanup standards. Use of such an approach would result in a common

dose criterion across an entire UR site, both for those areas

contaminated with radium and for those areas contaminated with uranium

and thorium. As noted above, the 5 pCi/g radium standard was

promulgated by EPA for UR sites. The 5 pCi/g radium value has also been

recommended as an exemption level by the Board of Directors of the

Conference of Radiation Control Program Directors (October 1998) for

the Suggested State Regulations on technologically enhanced naturally

occurring radioactive materials.

The NRC staff's preliminary dose modeling, using realistic

parameter values and the RESRAD code, indicates that at typical UR

facilities, where the background radiation results in doses of over 200

mrem/yr (2.0 mSv/yr), the Ra-226 standard of 5 pCi/g (0.19 Bq/g) could

typically result in a potential peak annual dose on the order of 20 to

35 mrem/yr (0.2 to 0.35 mSv/yr) to the average member of the critical

group. Although it is possible that some site-

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specific parameter values and subsurface contamination could result in

a higher benchmark dose than that estimated by the staff for the

various scenarios, the staff has high confidence that a site-specific

dose using the benchmark approach will typically be a small fraction of

100 mrem/yr (1 mSv/yr), and in all cases will not exceed 100 mrem/yr (1

mSv/yr). The rule also requires licensee's to demonstrate that doses

are ALARA which should result in a potential dose of less than 25 mrem/

yr (0.2 mSv/yr) from the residual Ra-226 on the remediated site for

most sites. Therefore, the potential health risk should be similar to

the NRC dose limit established for other facilities in Part 20, subpart

E, and approximate the level suggested in the EPA comment.

The radium benchmark dose modeling results are greater than the 5

pCi/g (0.19 Bq/g) radium modeling results reported by the EPA. The main

reason for the difference in results is that the EPA modeled a much

smaller area of contamination than that used by NRC staff (100 m\2\

versus 404,687 m\2\). Also, EPA modeled a much smaller fraction of time

an individual would spend outdoors (0.02 versus 0.25) and used a less

conservative root depth value (0.9 versus 0.25 meters) which generally

decreases the calculated potential dose. What is not factored into the

dose modeling is the low probability of anyone constructing a house or

growing a large garden on the areas of residual contamination at these

facilities. The UR facilities are in semi-arid (7-15 inches (18-39 cm)

annual precipitation), sparsely populated areas (1-13 persons/mile\2\

(0.4-5 persons/km\2\)) where mining and grazing (3 cows/acre (1 cow/

1348 m\2\)) are the main land uses.

The existing regulatory framework does not provide criteria for the

cleanup of radionuclides other than radium in soil. Also, the existing

guidance does not provide dose criteria, so additional criteria are

warranted. In areas where there is more than one residual radionuclide,

the benchmark dose would apply to the sum of all radionuclides present

in that area (i.e., radium, uranium, thorium, etc.). This is indicated

in the rule text, and in draft guidance for implementation of the

benchmark approach, where it is stated that, for each 100 m2

area, the unity rule will apply such that the sum of the ratios for

each radionuclide of the concentration present to the concentration

limit may not exceed ``1'' (i.e., unity). The rule text and guidance

also stipulate that the total effective dose equivalent limit is based

on the peak annual dose within a 1000 year period to the average member

of the critical group. This time frame is in keeping with the EPA

regulatory time frame for these facilities (40 CFR Part 192).

Only portions of uranium mill sites and no portion of ISL

facilities are anticipated to be turned over to the custodial care of

Government entities. The radium standard applies to all areas of a site

except the disposal cell, regardless of future use. The NRC staff plans

a similar approach for the criteria for other radionuclides. The

restricted use of areas that will be in perpetual custodial care could

be considered under the ALARA provision, if cleanup is difficult or

expensive in these areas.

B. Radionuclides at UR Sites are Naturally Occurring and of Variable

Concentration in Nature

Several commenters indicated that the residual radionuclides at UR

sites (uranium, thorium, radium) are naturally occurring in the local

environment and that there is significant variability in soil

background concentrations of these radionuclides, in particular at UR

facilities where uranium pit mines or mineral outcrops exist. This

leads to variability in potential dose such that the 25 mrem/yr (0.25

mSv/yr) dose in Part 20 subpart E would be indiscernible in the natural

variability of background at a UR site. Any concentration standard must

account for the significant variability in background and state that

the limits are for ``concentrations above background'' at the different

areas of the site. Also, two commenters indicated that a statistical

approach, not just an average value, should be used to determine the

background values for a site.

It was also mentioned that measurement of U-238 and Th-230 at

levels above background, which result in an annual dose to residents of

25 mrem (0.25 mSv), would not be possible using reasonably available

field techniques and that the additional cost of laboratory analyses to

demonstrate compliance could be $100,000 per acre.

Several commenters stated that there is no reliable way to

distinguish natural (in situ) ore material from processed (licensed)

ore. A related concern was that decommissioning standards for UR

facilities must not regulate mining activities and the associated ore

material that may be present at UR sites.

B. Response: As noted above in Section II, and as described in the

rule implementation guidance, the radionuclide dose limit is applied to

the level of licensed (byproduct) material distinguishable from

background. Site cleanup guidance indicates that background values

should be based on areas with characteristics similar to the

contaminated area(s) and that distinct areas of the site could have

different background values. Statistical approaches, such as those

discussed in the Multi-Agency Radiation Survey and Site Investigation

Manual (NUREG-1575, 1997), will be considered.

Field measurements for soil U-nat and Th-230 in general are

difficult and not just in the concentration equivalent of 25 mrem/yr

(0.25 mSv/yr). Laboratory measurements are practical because site-

specific dose modeling provides derived concentration limits for U-nat

and Th-230 that can exceed current guideline values. For most sites,

cleanup of soil U-nat and Th-230 would involve less than an acre (4,047

m2). Therefore, the costs of sampling and of laboratory

analysis for these radionuclides would be a minor part of the

decommissioning costs.

Distinguishing in situ ore from processed ore material can be a

problem on some sites and is addressed in the guidance. The NRC will

regulate only NRC-licensed materials remaining at UR facilities, not in

situ ore or mine waste. In determining compliance with the new

regulation, the NRC staff will consider 10 CFR 40.42 (j) and (k) that

state, in part, that as a final step in decommissioning, the licensee

shall demonstrate that the site is suitable for release and that

reasonable effort has been made to eliminate residual radioactive

contamination.

C. Considerations of Risks, Costs, and Benefits of Cleanup

Several commenters pointed out that the actual risk of excavating

and moving dirt (construction and transport accident risks that are

actuarial) must be compared against health risks of radiation exposure

which have not been demonstrated below 10 rem/yr (0.1 Sv/yr). The risk

of cleaning up areas to below regional background levels would likely

result in net human health and environmental detriment. Lowering of the

current radium standard for uranium and thorium could cause undue

economic burden to industry and the Government based on the need for

cleanup of large soil areas and would not result in significant (if

any) risk reduction.

At ISL facilities, lowering dose criteria could result in large

areas retroactively becoming disposal areas requiring substantial and

costly cleanup, and could inhibit efficiency of mining if irrigation

practices with restoration fluids were effectively prohibited.

[[Page 17509]]

C. Response: The NRC considered the risk of the cleanup work in the

regulatory analysis. The radium standard is not lowered by the

rulemaking; therefore, there is no undue economic burden for licensees.

Providing a radium benchmark dose standard for U-nat and Th-230 should

not result in significant decrease in the soil concentration allowed to

remain, compared to current guidance.

D. Regulatory Guidance

Several commenters offered suggestions for regulatory guidance and

requested that the regulatory guidance implementing the standard

include determination of background and dose modeling flexibility.

D. Response: The NRC recognizes that there may be difficulties in

the determination of background concentrations of radionuclides at some

UR facility sites. The NRC staff has prepared guidance (in the form of

evaluation criteria) on mill site cleanup in the draft Standard Review

Plan (SRP) for reclamation plans. This draft SRP will soon be published

for public comment. The NRC staff is preparing another chapter of this

SRP to address the implementation of the radium benchmark dose approach

and dose modeling flexibility for this unique set of licensees. This

chapter will also be published as a draft for public comment before

finalization and incorporation into the SRP.

IV. Agreement State Compatibility

This rule will be a matter of compatibility between the NRC and the

Agreement States, thereby providing consistency among State and Federal

safety requirements. The final rule on radiological criteria for

license termination for nuclear facilities issued July 21, 1997 (62 FR

39058), was determined to be a Division 2 matter of compatibility under

the previous Commission policy for Agreement State compatibility. As

noted for that final rule (at 62 FR 39079), Division 2 rules address

basic principles of radiation safety and regulatory functions. Although

Agreement States must address these principles in their regulations,

the use of language identical to that in NRC rules is not necessary if

the underlying principles are the same. Also, the Agreement States may

adopt requirements more stringent than NRC rules. Under the current NRC

policy, Category C compatibility would be consistent with that

indicated in 62 FR 39079, and, hence, the NRC has determined that this

rule will be a Category C matter of compatibility.

V. Finding of No Significant Environmental Impact: Availability

The NRC has determined under the National Environmental Policy Act

of 1969, as amended, and the regulations in Subpart A of 10 CFR Part

51, that this rule will not be a major Federal action significantly

affecting the quality of the human environment and, therefore, an

environmental impact statement is not required. The final rule amends

the NRC's regulations in 10 CFR Part 40 to include radiological dose

criteria for decommissioning of lands and structures at UR facilities.

The rule will affect 11 current NRC licensees. The environmental impact

of this rule will be insignificant compared to current practice and to

the decommissioning process in general because the areas requiring

cleanup for residual radionuclides other than radium are small.

The final environmental assessment and finding of no significant

impact on which this determination is based are available for

inspection in the NRC Public Document Room, 2120 L Street NW (Lower

Level), Washington, DC. Single copies of the environmental assessment

and the finding of no significant environmental impact are available

from Elaine Brummett, Office of Nuclear Material Safety and Safeguards,

U.S. Nuclear Regulatory Commission, Mailstop T7-J9, Washington, DC

20555-0001, telephone (301) 415-6066.

VI. Paperwork Reduction Act Statement

This final rule does not contain a new or amended information

collection requirement subject to the Paperwork Reduction Act of 1995

(44 U.S.C. 3501 et seq.). Existing requirements were approved by the

Office of Management and Budget, approval number 3150-0014.

Public Protection Notification

If an information collection does not display a currently valid OMB

control number, the NRC may not conduct or sponsor, and a person is not

required to respond to, the information collection.

VII. Regulatory Analysis

The NRC has prepared a regulatory analysis on this final

regulation. The analysis examines the costs and benefits of the

alternatives considered by the NRC. The analysis is available for

inspection in the NRC Public Document Room, 2120 L Street NW (Lower

Level), Washington, DC. Single copies of the analysis may be obtained

from Frank Cardile, Office of Nuclear Material Safety and Safeguards,

U.S. Nuclear Regulatory Commission, Mailstop T-C24, Washington, DC

20555-0001, telephone (301) 415-6185.

VIII. Regulatory Flexibility Certification

As required by the Regulatory Flexibility Act of 1980, 5 U.S.C.

605(b), the NRC certifies that this rule, if adopted, does not have a

significant economic impact upon a substantial number of small

entities. The rule will affect 11 current NRC licensees and any future

licensees who will be conducting uranium milling operations. These

licensees are not small entities as defined in 10 CFR 2.810.

IX. Backfit Analysis

The NRC has determined that the backfit rule, 10 CFR 50.109, does

not apply to this final rule and therefore, a backfit analysis is not

required for this final rule because these amendments do not involve

reactor operations and do not involve any provisions that would impose

backfits as defined in 10 CFR 50.109(a)(1).

X. Small Business Regulatory Enforcement Fairness Act

In accordance with the Small Business Regulatory Enforcement

Fairness Act of 1996, the NRC has determined that this action is not a

``major'' rule and has verified this determination with the Office of

Information and Regulatory Affairs, Office of Management and Budget.

XI. Criminal Penalties

For the purposes of Section 223 of the Atomic Energy Act (AEA), the

NRC is issuing the final rule under one or more of sections 161b, 161i,

or 161o of the AEA. Willful violations of the rule will be subject to

criminal enforcement.

List of Subjects in 10 CFR Part 40

Criminal penalties, Government contracts, Hazardous materials

transportation, Nuclear materials, Reporting and recordkeeping

requirements, Source material, Uranium.

For the reasons set out in the preamble and under the authority of

the Atomic Energy Act of 1954, as amended; the Energy Reorganization

Act of 1974, as amended; and 5 U.S.C. 552 and 553; the NRC is adopting

the following amendments to 10 CFR Part 40.

PART 40--DOMESTIC LICENSING OF SOURCE MATERIAL

1. The authority citation for Part 40 continues to read as follows:

Authority: Secs. 62, 63, 64, 65, 81, 161, 182, 183, 186, 68

Stat. 932, 933, 935, 948,

[[Page 17510]]

953, 954, 955, as amended, secs. 11e(2), 83, 84, Pub. L. 95-604, 92

Stat. 3033, as amended, 3039, sec. 234, 83 Stat. 444, as amended (42

U.S.C. 2014(e)(2), 2092, 2093, 2094, 2095, 2111, 2113, 2114, 2201,

2232, 2233, 2236, 2282); sec. 274, Pub. L. 86-373, 73 Stat. 688 (42

U.S.C. 2021); secs. 201, as amended, 202, 206, 88 Stat. 1242, as

amended, 1244, 1246 (42 U.S.C. 5841, 5842, 5846); sec. 275, 92 Stat.

3021, as amended by Pub. L. 97-415, 96 Stat. 2067 (42 U.S.C. 2022);

193, 104 Stat. 2835 as amended by Pub. L. 104-134, 110 Stat. 1321,

1321-349 (42 U.S.C. 2243).

Section 40.7 also issued under Pub. L. 95-601, sec. 10, 92 Stat.

2951 (42 U.S.C. 5851). Section 40.31(g) also issued under sec. 122,

68 Stat. 939 (42 U.S.C. 2152). Section 40.46 also issued under sec.

184, 68 Stat. 954, as amended (42 U.S.C. 2234). Section 40.71 also

issued under sec. 187, 68 Stat. 955 (42 U.S.C. 2237).

2. In 10 CFR Part 40, Appendix A, Criterion 6(6), a second

paragraph is added to read as follows:

Appendix A to Part 40

* * * * *

I. Technical Criteria

* * * * *

Criterior 6 * * *

(6) * * *

Byproduct material containing concentrations of radionuclides other

than radium in soil, and surface activity on remaining structures, must

not result in a total effective dose equivalent (TEDE) exceeding the

dose from cleanup of radium contaminated soil to the above standard

(benchmark dose), and must be at levels which are as low as is

reasonably achievable. If more than one residual radionuclide is

present in the same 100-square-meter area, the sum of the ratios for

each radionuclide of concentration present to the concentration limit

will not exceed ``1'' (unity). A calculation of the potential peak

annual TEDE within 1000 years to the average member of the critical

group that would result from applying the radium standard (not

including radon) on the site must be submitted for approval. The use of

decommissioning plans with benchmark doses which exceed 100 mrem/yr,

before application of ALARA, requires the approval of the Commission

after consideration of the recommendation of the NRC staff. This

requirement for dose criteria does not apply to sites that have

decommissioning plans for soil and structures approved before June 11,

1999.

* * * * *

Dated at Rockville, Maryland, this 6th day of April 1999.

For the Nuclear Regulatory Commission.

Annette L. Vietti-Cook,

Secretary of the Commission.

[FR Doc. 99-9035 Filed 4-9-99; 8:45 am]

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