ML080240439

Request for Exemption from 10 CFR Appendix B, Table 1 Values

ML080240439
Person / Time
Site:	Humboldt Bay
Issue date:	02/25/2008
From:	Mcconnell K NRC/FSME/DWMEP/DURLD
To:	Conway J Pacific Gas & Electric Co
Hickman J (301) 415-3017
References
TAC J00335
Download: ML080240439 (16)

Text

February 25, 2008 Mr. John T. Conway Site Vice President and Chief Nuclear Officer Pacific Gas and Electric Company P. O. Box 3 Mail Code 104/6/601 Avila Beach, CA 93424

SUBJECT:

HUMBOLDT BAY POWER PLANT UNIT 3 - REQUEST FOR EXEMPTION FROM 10 CFR APPENDIX B, TABLE 1 VALUES (TAC No. J00335)

Dear Mr. Conway:

By letter dated October 30, 2007, you requested an exemption from the values to be used at Humboldt Bay Power Plant, Unit 3 (HBPP) regarding the Inhalation Annual Limits on Intake (ALIs) and Derived Air Concentrations (DACs). These values appear in 10 CFR 20, Appendix B, Table 1, and are referenced in 10 CFR 20.1201(d). You proposed replacing the ALl and DAC values, derived using earlier (1977) recommendations of the International Commission on Radiological Protection (ICRP), with ALl and DAC values derived using more recent (1995)

ICRP recommendations.

In accordance with your application dated October 30, 2007, and pursuant to Part 20.2301 to Title 10 of the Code of Federal Regulations (CFR), the Nuclear Regulatory Commission (NRC) staff has determined that granting this exemption to 10 CFR 20.1201(d) is authorized by law, will not endanger life, property, common defense and security, and is otherwise in the public interest. Accordingly, you are authorized to use the ALl and DAC values derived using the (1995) ICRP recommendations.

Regarding this proposed action, the NRC staff performed an Environmental Assessment (EA) resulting in a Finding of No Significant Impact (FONSI), pursuant to 10 CFR Part 51. On January 22, 2008, the FONSI was published in the Federal Register (73 FR 3757-3759).

Enclosed are copies of the Safety Evaluation Report (Enclosure 1), and the Federal Register Notice containing NRCs EA and FONSI (Enclosure 2).

J. Conway 2

If you have any questions regarding this matter, please contact John Hickman of my staff at (301) 415-3017 or via e-mail to jbh@nrc.gov.

In accordance with 10 CFR 2.390 of the NRCs Rules of Practice, a copy of this letter and its enclosures will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of NRCs Agencywide Documents Access and Management System (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).

Sincerely,

/RA/

Keith I. McConnell, Deputy Director Decommissioning and Uranium Recovery Licensing Directorate Division of Waste Management and Environmental Protection Office of Federal and State Materials and Environmental Management Programs Docket No.: 50-133 License No.: DPR-7

Enclosures:

1. Safety Evaluation Report

2. Federal Register Notice containing NRCs EA/FONSI cc: Unit 3 Service List

J. Conway 2

If you have any questions regarding this matter, please contact John Hickman of my staff at (301) 415-3017 or via e-mail to jbh@nrc.gov.

In accordance with 10 CFR 2.390 of the NRCs Rules of Practice, a copy of this letter and its enclosures will be available electronically for public inspection in the NRC Public Document Room or from the Publicly Available Records (PARS) component of NRCs Agencywide Documents Access and Management System (ADAMS). ADAMS is accessible from the NRC Web site at http://www.nrc.gov/reading-rm/adams.html (the Public Electronic Reading Room).

Sincerely,

/RA/

Keith I. McConnell, Deputy Director Decommissioning and Uranium Recovery Licensing Directorate Division of Waste Management and Environmental Protection Office of Federal and State Materials and Environmental Management Programs Docket No.: 50-133 License No.: DPR-7

Enclosures:

1. Safety Evaluation Report

2. Federal Register Notice containing NRCs EA/FONSI cc: Unit 3 Service List DISTRIBUTION:

Docket File 50-29 RidsAcrsAcnwMailCenter RidsOgcMailCenter KMcConnell APersinko JHickman ML080240439 OFFICIAL RECORD COPY OFFICE DWMEP: PM DWMEP: LA DWMEP: HP DWMEP: BC OGC DWMEP: DD NAME J. Hickman T. Mixon T. Youngblood A. Persinko J.Hull K. McConnell DATE 01/29/08 01/28/08 01/31/08 02/05/08 02/12/08 02/25/08

Humboldt Bay Power Plant, Unit 3 Service List cc:

Mr. John S. Keenan Senior Vice President Generation and Chief Nuclear Officer Pacific Gas and Electric Company P. O. Box 770000 Mail Code B32 San Francisco, CA 94177-0001 Ms. Donna Jacobs Vice President, Nuclear Services Diablo Canyon Power Plant P.O. Box 56 Avila Beach, CA 93424 James Becker Vice President - Diablo Canyon Operations and Station Director Diablo Canyon Power Plant PO Box 56 Avila Beach, CA 93424 R. Terry Nelson, Director and Plant Manager, Humboldt Bay Nuclear Pacific Gas & Electric Company 1000 King Salmon Avenue Eureka, CA 95503 Mr. Antonio Fernandez, Esq.

Law Department Pacific Gas & Electric Company Post Office Box 7442 San Francisco, CA 94120 Chairman, Humboldt County Board of Supervisors County Courthouse 825 Fifth Street Eureka, CA 95501 Mr. Steve Hsu Radiologic Health Branch State Department of Health Services P.O. Box 997414 (MS 7610)

Sacramento, CA 95899-7414 Regional Administrator, Region IV U.S. Nuclear Regulatory Commission 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011-8064 California Public Utilities Commission 505 Van Ness, Room 4102 San Francisco, CA 94102 California Public Utilities Commission 505 Van Ness, Room 4102 San Francisco, CA 94102 Redwood Alliance P.O. Box 293 Arcata, CA 95521 Dr. Rich Ferguson, Energy Chair Sierra Club California 1100 11th Street, Suite 311 Sacramento, CA 94814 Mr. Ed Bailey, Radiation Program Director Radiologic Health Branch State Department of Health Services P.O. Box 997414 (MS 7610)

Sacramento, CA 95899-7414 Commissioner California Energy Commission 1516 Ninth Street Sacramento, CA 95814 Deputy Attorney General State of California 110 West A Street, Suite 700 San Diego, CA 92101

SAFETY EVALUATION BY OFFICE OF FEDERAL AND STATE MATERIALS AND ENVIRONMENTAL MANAGEMENT PROGRAMS RELATED TO EXEMPTION FROM 10 CFR 20.1201(d)

PACIFIC GAS AND ELECTRIC COMPANY HUMBOLDT BAY POWER PLANT, UNIT 3 DOCKET NO. 50-133

1.0 INTRODUCTION

By letter dated October 30, 2007, Pacific Gas and Electric Company (PG&E, the licensee) submitted to the NRC, a request for an exemption from the values of the Inhalation Annual Limits on Intake (ALIs) and Derived Air Concentrations (DACs) that appear in 10 CFR 20, Appendix B, Table 1, for use at Humboldt Bay Power Plant, Unit 3 (HBPP). PG&E proposed replacing the 10 CFR 20, Appendix B, Table 1 ALl and DAC values, derived using earlier (1977) recommendations of the International Commission on Radiological Protection (ICRP), with ALl and DAC values derived using more recent (1995) ICRP recommendations.

2.0 BACKGROUND

On July 2, 1976, Humboldt Bay Power Plant (HBPP) Unit 3 was shut down for annual refueling and to conduct seismic modifications. In 1983, updated economic analyses indicated that restarting Unit 3 would probably not be cost-effective, and in June 1983, PG&E announced its intention to decommission the unit. On July 16, 1985, the NRC issued Amendment No. 19 to the HBPP Unit 3 Operating License to change the status to possess-but-not-operate, and the plant was placed into a SAFSTOR status. SAFSTOR is the decommissioning method in which a nuclear facility is placed and maintained in a condition that allows the safe storage of radioactive components of the nuclear plant and subsequent decontamination to levels that permit license termination.

The NRC approved the HBPP Unit 3 SAFSTOR Decommissioning Plan (DP) in July 1988.

Pursuant to the 1996 NRC decommissioning rule, 10 CFR 50.82, and subsequent discussions with the NRC, the HBPP DP was converted into a Defueled Safety Analysis Report (DSAR) and a Post Shutdown Decommissioning Activities Report (PSDAR). The DSAR is updated every two years in accordance with 10 CFR 50.71. The plant is currently in SAFSTOR with incremental decommissioning activities ongoing.

In December 2003, PG&E formally submitted a license application to the U.S. Nuclear Regulatory Commission (NRC) for approval of a dry-cask Independent Spent Fuel Storage Installation (ISFSI) at the Humboldt Bay site. A license and safety evaluation report for the Humboldt Bay ISFSI were issued on November 17, 2005. PG&E is preparing to transfer spent fuel currently in the SFP to the ISFSI in 2008, which will facilitate increased decommissioning activities in Unit 3.

2 Fuel failures occurred at HBPP in the past when the reactor was operating, resulting in contamination from alpha emitters which pose an inhalation hazard to workers. The inhalation of airborne radioactive materials in restricted areas poses a potential internal radiation hazard and the NRC regulations in 10 CFR Part 20 require licensees to assess these radiation hazards and to implement protective measures to minimize that hazard to workers, the public and the environment. These actions and measures include air sampling, posting airborne radioactivity area warning signs, the use of respiratory protection, and bioassay monitoring of workers.

These actions and measures are triggered when air concentrations in the workplace reach specified fractions of the DAC values in 10 CFR Part 20, Appendix B.

3.0 REGULATORY EVALUATION

The basic limits on radiation exposures, as well as the minimum radiation protection practices required of any NRC licensee, are specified in 10 CFR Part 20, Standards for Protection Against Radiation. Part 20 underwent a major revision in the 1980's, and the revised regulation was published as a proposed rule in December 1985. The final rule was published in the Federal Register on May 21, 1991 (56 FR 23391), and became mandatory for all licensees in January 1994.

One of the major changes incorporated in the revised Part 20 was the manner in which internal exposure to radioactive materials is regulated. Before the revision, the NRC regulated internal exposures by limiting the amounts of radioactive materials that may be taken into the body over specified time periods. The revised Part 20 eliminated regulation based on intakes and regulated instead, on the basis of the dose that resulted from those intakes. The internal dose from intake of radioactive material is referred to in Part 20 as the committed effective dose equivalent (CEDE). The regulation of dose instead of intake was prompted by recommendations provided by national and international bodies, and also by the desire to end the traditional treatment of internal and external doses as two separate entities. The dose based rule removes the requirement to use a specific set of parameters to calculate the dose. Part 20 allows adjustments to the model parameters if specific information is available, such as adjustments for the particle size of airborne radioactive material, rather than using a default particle size. However, Part 20 also specifies increased radiation protection based on DAC and ALI values as tabulated in Appendix B, rather than in terms of dose. Thus, requirements such as posting of airborne radioactivity areas, monitoring for intakes of radioactive materials, establishment of bioassay programs, and use of respirators are explicitly tied to the measurable quantities of contamination, rather than to a dose. This approach was taken to avoid imposing an undue calculation burden on the licensee.

The models used in Part 20 to regulate internal dose are those described in ICRP Publications 26 and 30, adopted by ICRP in 1977 and 1978, respectively. Much of the basic structure of these models were developed in 1966, with few modifications before their formal adoption by ICRP in 1978. In the same year that the Commission approved the final Part 20 rule, ICRP published a major revision of its radiation protection recommendations (ICRP 60). Within the several years following this revision, ICRP published a series of reports in which it described the components of an extensively updated and revised internal dosimetry model. These reports include ICRP Publications 60 (1990), 66 (1993), 67 (1993), 68 (1994), 71 (1995), 72 (1995), and 78 (1997). The NRC licensees are not permitted to use the revised and updated internal dosimetry models unless an exemption to 10 CFR 20.1201(d) is granted.

3

4.0 TECHNICAL EVALUATION

PG&E has requested that NRC allow an exemption under 10 CFR Part 20.2301 to allow the use of DAC and ALI values calculated using ICRP-68, ADose Coefficients for Intake of Radionuclides by Workers,@ (Ref. 3) dose coefficients and parameters instead of the DAC and ALI values in 10 CFR Part 20, Appendix B, Table 1, Occupational Values. HBPP believes that this change will result in greater worker efficiency in decommissioning work activities and should result in an overall reduction in worker dose. The ICRP 68 parameters used in calculating DAC and ALI values are generally accepted as more representative models of the actual physical and biological mechanisms involved in the inhalation and deposition of aerosols in the human body.

The Department of Energy (DOE) adopted the ICRP-68 recommendations for DAC and ALI values in a revision to 10 CFR Part 835, Occupational Radiation Protection, earlier this year (Ref. 4). Also, the Commission has indicated in Staff Requirements Memoranda for SECY 148 (Ref. 5) and SECY-99-077 (Ref. 6) that the NRC staff should consider and approve, as appropriate, licensee requests to use more recent ICRP radiation protection recommendations on a case-by-case basis. The licensee states that the exemption is allowed by NRC regulations and will not result in any new or increased hazard to life of property.

To protect plant workers from doses due to inhalation of alpha emitters, the HBPP internal exposure control program requires the use of respirators when performing certain activities.

Using a respirator reduces worker efficiency and requires workers to remain in radiation areas longer than if respirators were not used. By remaining in a radiation area longer than necessary, workers receive higher external doses due to gamma radiation. At the present time, plant workers are actively performing preparatory decommissioning activities that are scheduled to increase in mid-2008 after spent nuclear fuel assemblies and fuel fragment containers are transferred from the spent fuel pool to the ISFSI.

The DAC and ALI values in 10 CFR Part 20, Appendix B, Table 1, were calculated using ICRP 26 and ICRP 30 radiation dosimetry methodology. This methodology was adopted by the ICRP in 1977 and 1978, respectively. The ICRP has continued to update and revise its dosimetric models and input parameters as new information became available. The current ICRP basic radiation protection recommendations are in ICRP 60 which was adopted in 1990. HBPP proposes to use the dose coefficients for intake of radionuclides by workers in ICRP-68 which were adopted for use by ICRP in 1994.

The differences in the values between the current NRC DAC values and values for most radionuclides using more recent ICRP methodology are generally two-fold or less. However, the difference between some radionuclides is larger - especially for uranium and some of the transuranic radionuclides. HBPP has provided a comparison of inhalation ALIs for these radionuclides. ICRP-68 inhalation ALI values are greater than ICRP-30 values by a factor of 4.9 for U-235; 6.1 for Pu-238; 2.0 for Am-241; and 5.0 for Np-237.

Engineering controls are the preferred method to control airborne radioactive materials, but this is more difficult to implement for the changing conditions in decommissioning activities than during routine operations. The use of ICRP-68 dose coefficients and parameters to develop DAC and ALI values should result in less conservative values than those currently in 10 CFR Part 20. This should reduce the reliance on respirators to prevent the inhalation of airborne radioactivity by workers, and this should improve worker=s ability to better identify and avoid industrial safety hazards and also should reduce physical stresses on workers. The reduced

4 reliance on respirators will also allow workers to perform activities in radiation areas more efficiently, reducing external radiation dose due to gamma rays, and resulting in reduced overall dose received. Therefore, PG&Es request for an exemption under 10 CFR Part 20.2301 is acceptable because it gives its workers equivalent radiological protection as required by 10 CFR Part 20. Thus, the exemption is authorized by law and will not result in an undue hazard to life or property.

5.0 ENVIRONMENTAL REVIEW The NRC staff concludes that the applicants conformance to its application and license conditions provides adequate assurance of the protection of the health and safety of the public and workers, is adequate to protect the environment, and complies with the regulatory requirements imposed by the Commission in 10 CFR Parts 20, 51, and 70.

The basis for this conclusion is documented in an Environmental Assessment (EA) which was prepared in support of the enclosed amendment. On January 22, 2008, a Federal Register Notice was published (73 FR 3757-3759) which contained the EA and a Finding of No Significant Impact.

6.0 CONCLUSION

It is generally agreed among the national and international scientific community that newer models provide a more up-to-date basis for calculating exposure to radioactive materials and compliance with the dose limits. Further, the licensees use of these newer models is in compliance with the requirements in 10 CFR Part 20. Also, the NRC supports these types of dose estimates, and has authorized the staff to grant exemptions on a case-by-case basis (Ref.

6). Therefore, the staff approves the licensees request to use the new models.

7.0 REFERENCES

1. J. S. Keenan, Pacific Gas and Electric Company, letter to the U.S. Nuclear Regulatory Commission, AExemption Request From 10 CFR 20 Appendix B, Table 1 Values,@ October 30, 2007. (ML073060034)

2. U.S. Code of Federal Regulation, AStandards for Protection Against Radiation,@ Part 20, Chapter 1, Title 10, Energy.

3. International Commission on Radiological Protection Publication 68, Dose Coefficients for Intakes of Radionuclides by Workers, published July, 1994 (ISBN 0 08 042651 4). This document is available from Elsevier Science Inc., Tarrytown, NY.

4. Federal Register Notice, Friday, June 8, 2007 (FR Vol. 72, No.110, Pages 31904 - 31941),

DOE Final Rule for the adoption of current ICRP methodology for DAC and ALI values in 10 CFR 835, Occupational Radiation Protection.

5. SECY-01-148, Staff Requirements B SECY-01-0148 - Processes for Revision of 10 CFR Part 20 Regarding Adoption of ICRP Recommendations on Occupational Dose Limits and Dosimetric Models and parameters, April 12, 2002. (ML011580363)

5

6. SECY-99-077, Staff Requirements B SECY-99-0077 B To Request Commission Approval to Grant Exemptions From Portions of 10 CFR Part 20, April 21, 1999. (ML042750086)

The NRC Public Documents Room is located at NRC Headquarters in Rockville, MD, and can be contacted at (800) 397-4209. Documents may be examined, and/or copied for a fee, at the NRC=s Public Document Room (PDR), located at One White Flint North, 11555 Rockville Pike (first floor), Rockville, Maryland. Publicly available records will be accessible electronically from the Agencywide Documents Access and Management System's (ADAMS) Public Library component on the NRC Web site, http://www.nrc.gov (the Public Electronic Reading Room).

Persons who do not have access to ADAMS or who encounter problems in accessing the documents located in ADAMS should contact the NRC PDR Reference staff by telephone at 1-800-397-4209, or 301-415-4737, or by e-mail at pdr@nrc.gov.

[7590-01-P]

U.S. NUCLEAR REGULATORY COMMISSION

[Docket No. 50-133]

Environmental Assessment and Finding of No Significant Impact Related to Issuance of Exemption for the Humboldt Bay Power Plant Unit 3 License DPR-007, Humboldt, California AGENCY: U.S. Nuclear Regulatory Commission ACTION: Environmental Assessment and Finding of No Significant Impact FOR FURTHER INFORMATION CONTACT: John Hickman, Division of Waste Management and Environmental Protection, Office of Federal and State Materials and Environmental Management Programs, U.S. Nuclear Regulatory Commission, Mail Stop: T8F5, Washington, DC 20555-00001. Telephone: (301) 415-3017; e-mail: jbh@nrc.gov.

SUPPLEMENTARY INFORMATION:

I.

Introduction The U.S. Nuclear Regulatory Commission (NRC) staff is considering a request dated October 30, 2007, by the Pacific Gas and Electric Company (PG&E or the Licensee), to approve a request for exemption from the values of the Inhalation Annual Limits on Intake (ALIs) and Derived Air Concentrations (DACs) that appear in 10 CFR Part 20, Appendix B, Table 1, for use at Humboldt Bay Power Plant, Unit 3 (HBPP). PG&E proposes replacing the 10 CFR Part 20, Appendix B, Table 1 ALl and DAC values, derived using previous (1977) recommendations of the International Commission on Radiological Protection (ICRP), with ALl and DAC values derived using more recent (1995) ICRP recommendations.

2 This Environmental Assessment (EA) has been developed in accordance with the requirements of 10 CFR Part 51.21.

II. Environmental Assessment

Background:

HBPP was permanently shut down in July 1976, and until recently was in safe storage condition (SAFSTOR). SAFSTOR is defined as a method of decommissioning in which the nuclear facility is placed and maintained in safe condition for an extended period of time to permit radioactive material to decay to levels that facilitate subsequent decontamination and decommissioning of the facility. A Decommissioning Plan was approved in July 1988.

Subsequent to the1997 decommissioning rule, the licensee converted its decommissioning plan into its Defueled Safety Analysis Report which is updated every two years. A Post Shutdown Decommissioning Activities Report was issued by the licensee in February 1998. In December 2003, PG&E formally submitted a license application to the NRC for approval of a dry-cask Independent Spent Fuel Storage Installation (ISFSI) at the Humboldt Bay site. A preliminary license and safety evaluation report for the Humboldt Bay ISFSI was issued on August 24, 2005.

The ISFSI is currently under construction and the licensee is now engaged in some incremental decommissioning activities.

Fuel failures occurred at HBPP in the past when the reactor was operating, resulting in contamination from alpha emitters which pose an inhalation hazard to workers. The inhalation of airborne radioactive materials in restricted areas poses a potential internal radiation hazard and the NRC regulations in 10 CFR Part 20 require licensees to assess these radiation hazards and to implement protective measures to minimize that hazard to workers, the public and the environment. These actions and measures include air sampling, posting airborne radioactivity area warning signs, the use of respiratory protection, and bioassay monitoring of workers.

3 These actions and measures are triggered when air concentrations in the workplace reach specified fractions of the DAC values in 10 CFR Part 20, Appendix B.

Proposed Action:

HBPP has requested that NRC allow an exemption under 10 CFR Part 20.2301 to allow the use of DAC and ALI values calculated using ICRP-68, ADose Coefficients for Intake of Radionuclides by Workers,@ (Ref. 3) dose coefficients and parameters instead of the DAC and ALI values in 10 CFR Part 20, Appendix B, Table 1, Occupational Values. HBPP believes that this change will result in greater worker efficiency in decommissioning work activities and should result in an overall reduction in worker dose. The ICRP 68 parameters used in calculating DAC and ALI values are generally accepted as more representative models of the actual physical and biological mechanisms involved in the inhalation and deposition of aerosols in the human body.

The Department of Energy (DOE) adopted the ICRP-68 recommendations for DAC and ALI values in a revision to 10 CFR Part 835, Occupational Radiation Protection, earlier this year (Ref. 4). Also, the Commission has indicated in Staff Requirements Memoranda for SECY 148 (Ref. 5) and SECY-99-077 (Ref. 6) that the NRC staff should consider and approve, as appropriate, licensee requests to use more recent ICRP radiation protection recommendations on a case-by-case basis. The licensee states that the exemption is allowed by NRC regulations and will not result in any new or increased hazard to life of property.

Need for Proposed Action:

To protect plant workers from doses due to inhalation of alpha emitters, the HBPP internal exposure control program requires the use of respirators when performing certain activities.

Using a respirator reduces worker efficiency and requires workers to remain in radiation areas longer than if respirators were not used. By remaining in a radiation area longer than necessary, workers receive higher external doses due to gamma radiation. At the present time, plant

4 workers are actively performing preparatory decommissioning activities that are scheduled to increase in mid-2008 after spent nuclear fuel assemblies and fuel fragment containers are transferred from the spent fuel pool to the ISFSI.

II. Environmental Impacts of the Proposed Action:

Radiological Impacts:

The DAC and ALI values in 10 CFR Part 20, Appendix B, Table 1, were calculated using ICRP 26 and ICRP 30 radiation dosimetry methodology. This methodology was adopted by the ICRP in 1977 and 1978, respectively. The ICRP has continued to update and revise its dosimetric models and input parameters as new information became available. The current ICRP basic radiation protection recommendations are in ICRP 60 which was adopted in 1991.

HBPP proposes to use the dose coefficients for intake of radionuclides by workers in ICRP-68 which were adopted for use by ICRP in 1995.

The differences in the values between the current NRC DAC values and values for most radionuclides using more recent ICRP methodology are generally two-fold or less. However, the difference between some radionuclides is larger - especially for uranium and some of the transuranic radionuclides. HBPP has provided a comparison of inhalation ALIs for these radionuclides. ICRP-68 inhalation ALI values are greater than ICRP-30 values by a factor of 4.9 for U-235; 6.1 for Pu-238; 2.0 for Am-241; and 5.0 for Np-237.

Engineering controls are the preferred method to control airborne radioactive materials, but this is more difficult to implement for the changing conditions in decommissioning activities than during routine operations. The use of ICRP-68 dose coefficients and parameters to develop DAC and ALI values should result in less conservative values than those currently in 10 CFR Part 20. This should reduce the reliance on respirators to prevent the inhalation of airborne radioactivity by workers, and this should improve worker=s ability to better identify and avoid

5 industrial safety hazards and also should reduce physical stresses on workers. The reduced reliance on respirators will also allow workers to perform activities in radiation areas more efficiently, reducing external radiation dose due to gamma rays, and resulting in reduced overall dose received. Therefore, PG&Es request for an exemption under 10 CFR Part 20.2301 is acceptable because it gives its workers equivalent radiological protection as required by 10 CFR Part 20.

Non-Radiological Impacts:

The NRC has determined that there are no adverse non-radiological impacts associated with the proposed action.

Cumulative Impacts:

The NRC has determined that there are no adverse cumulative impacts associated with this proposed action.

Alternatives to the Proposed Action:

The alternative to considering the exemption request for approval is to deny the request.

The alternative was rejected by NRC because the impacts on workers, the public and the environment were not adversely affected by the requested action. The use of ICRP 68 recommendations to calculate DAC and ALI values should reduce potential industrial safety hazards to workers by lessening reliance on respirators and will not increase any hazards to the public or the environment.

Agencies and Persons Consulted:

The NRC contacted the California Radiologic Health Branch in the State Department of Health Services concerning this request. There were no comments, concerns or objections from the state official.

NRC staff determined that the proposed action is not a major decommissioning activity and will not affect listed or proposed endangered species, nor critical habitat. Therefore, no further

6 consultation is required under Section 7 of the Endangered Species Act. Likewise, NRC staff determined that the proposed action is not the type of activity that has the potential to cause previously unconsidered effects on historic properties, as consultation for site decommissioning has been conducted previously. There are no additional impacts to historic properties associated with the disposal method and location for demolition debris. Therefore, no consultation is required under Section 106 of the National Historic Preservation Act.

IV. Finding of No Significant Impact On the basis of the environmental assessment, the NRC concludes that the proposed action will not have a significant effect on the quality of the human environment. Accordingly, the NRC has determined that preparation of an environmental impact statement is not warranted for the proposed action.

V. Further Information For further information with respect to the proposed action, see the following documents:

1. J. S. Keenan, Pacific Gas and Electric Company, letter to the U.S. Nuclear Regulatory Commission, AExemption Request From 10 CFR 20 Appendix B, Table 1 Values,@ October 30, 2007. (ML073060034)

2. U.S. Code of Federal Regulation, AStandards for Protection Against Radiation,@ Part 20, Chapter 1, Title 10, Energy.

3. International Commission on Radiological Protection Publication 68, Dose Coefficients for Intakes of Radionuclides by Workers, published July, 1994 (ISBN 0 08 042651 4). This document is available from Elsevier Science Inc., Tarrytown, NY.

4. Federal Register Notice, Friday, June 8, 2007 (FR Vol. 72, No.110, Pages 31904 -

31941), DOE Final Rule for the adoption of current ICRP methodology for DAC and ALI values in 10 CFR 835, Occupational Radiation Protection.

7

5. SR-SECY-01-148, Staff Requirements B SECY-01-0148 - Processes for Revision of 10 CFR Part 20 Regarding Adoption of ICRP Recommendations on Occupational Dose Limits and Dosimetric Models and parameters, April 12, 2002. (ML011580363)

6. SR-SECY-99-077, Staff Requirements B SECY-99-0077 B To Request Commission Approval to Grant Exemptions From Portions of 10 CFR Part 20, April 21, 1999.

(ML042750086)

The NRC Public Documents Room is located at NRC Headquarters in Rockville, MD, and can be contacted at (800) 397-4209. Documents may be examined, and/or copied for a fee, at the NRC=s Public Document Room (PDR), located at One White Flint North, 11555 Rockville Pike (first floor), Rockville, Maryland. Publicly available records will be accessible electronically from the Agencywide Documents Access and Management System's (ADAMS) Public Library component on the NRC Web site, http://www.nrc.gov (the Public Electronic Reading Room).

Persons who do not have access to ADAMS or who encounter problems in accessing the documents located in ADAMS should contact the NRC PDR Reference staff by telephone at 1-800-397-4209, or 301-415-4737, or by e-mail at pdr@nrc.gov.

Dated at Rockville, Maryland, this 15 th day of January, 2008.

FOR THE NUCLEAR REGULATORY COMMISSION

/RA/

Keith I. McConnell, Deputy Director Decommissioning and Uranium Recovery Licensing Directorate Division of Waste Management and Environmental Protection Office of Federal and State Materials and Environmental Management Programs