DCL-02-095, Response to NRC Requests for Additional Information Regarding License Amendment Requests 01-04 and 01-05

From kanterella
Jump to navigation Jump to search
Response to NRC Requests for Additional Information Regarding License Amendment Requests 01-04 and 01-05
ML022340387
Person / Time
Site: Diablo Canyon  Pacific Gas & Electric icon.png
Issue date: 08/14/2002
From: Rueger G
Pacific Gas & Electric Co
To:
Document Control Desk, Office of Nuclear Reactor Regulation
References
DCL-02-095
Download: ML022340387 (9)


Text

i, I .

W PacificGas and Electric Company..

Gregory M. Rueger US Mail Senior Vice President- Mail Code B32 Generation and Pacific Gas and Electric Company Chief Nuclear Officer P0 Box 770000 San Francisco, CA 941770001 August 14, 2002 OvernightMail.

Mail Code 832 PG&E Letter DCL-02-095 Pacific Gas and Electric Company 77 Beale Street. 32nd Floor San Francisco. CA 94105-1814 U.S. Nuclear Regulatory Commission 4159734684 ATTN: Document Control Desk Fax 4159732313 Washington, DC 20555-0001 Docket No. 50-275, OL-DPR-80 Docket No. 50-323, OL-DPR-82 Diablo Canyon Units I and 2 Response to NRC Requests for Additional Information Regardinq License Amendment Request 01-04, "Revision to Technical Specifications 3.9.4 Containment Penetrations," and License Amendment Reouest 01-05, "Revision to Technical Specification 1.1, Definitions, Dose Equivalent 1-131, and Revised Steam Generator Tube Rupture and Main Steam Line Break Analyses"

Dear Commissioners and Staff:

On July 9, 2002 and March 1, 2002, respectively, the NRC staff identified additional information required in order to complete their evaluation associated with License Amendment Requests (LAR) 01-04 and 01-05.

LAR 01-04 proposes to revise the limiting condition for operation for Technical Specification (TS) 3.9.4, "Containment Penetrations," to allow the equipment hatch, both personnel air lock doors and both emergency air lock doors to remain open, and penetration flow path(s) providing direct access from the containment atmosphere to the outside atmosphere to be unisolated under administrative control, during core alterations and movement of irradiated fuel assemblies. LAR 01-04 was submitted by PG&E Letter DCL-01-104, "License Amendment Request 01-04, Revision To Technical Specifications 3.9.4 Containment Penetrations," dated October 17, 2001. PG&E Letter DCL-02-020, "Supplement I to License Amendment Request 01-04, Revision To Technical Specifications 3.9.4 Containment Penetrations," dated February 26, 2002, provided guidance that would be used in case of weather conditions that could necessitate closure of the containment equipment hatch.

A member of the STARS (Strateglc Teamfng and Resource Sharing) Alliance Calaway # Comanche Peak

  • Olablo Canyon # Palo Verde
  • South Texas Project @Wolf Creek

Document Control Desk PG&E Letter DCL-02-095 August 14, 2002 Page 2 LAR 01-05 proposes to modify TS 1.1, "Definitions, Dose Equivalent 1-131," to allow use of thyroid dose conversion factors listed in International Commission on Radiological Protection Publication 30, "Limits for Intakes of Radionuclides by Workers," 1979, in the Steam Generator Tube Rupture and Main Steam Line Break radiological consequences analyses. LAR 01-05 was submitted by PG&E Letter DCL-01 -115, "License Amendment Request 01-05, Revision to Technical Specification 1.1, Definitions, Dose Equivalent 1-131, and Revised Steam Generator Tube Rupture and Main Steam Line Break Analyses," dated November 16, 2001.

PG&E's responses to the requests for additional information are included in Enclosures 1 and 2, respectively, for LAR 01-04, and LAR 01-05.

This additional information does not affect the results of the safety evaluations and no significant hazards determinations previously transmitted in PG&E Letters DCL-01 -104, and DCL-01 -115.

If you have any questions regarding this response, please contact Patrick Nugent at (805) 545-4720.

Sir erely, Gregy M._u eger Senior ice President- Generationand Chief Nuclear Officer JER Enclosures cc: Edgar Bailey, DHS Ellis W. Merschoff David L. Proulx Girija S. Shukla Diablo Distribution A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callaway v ComanchePeak

  • Diablo Canyon e Palo Verde v South Tefas Project v Wolf Creek

PG&E Letter DCL-02-095 UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION

) Docket No. 50-275 In the Matter of ) Facility Operating License PACIFIC GAS AND ELECTRIC COMPANY) No. DPR-80

)

Diablo Canyon Power Plant ) Docket No. 50-323 Units 1 and 2 ) Facility Operating License

) No. DPR-82 AFFIDAVIT Gregory M. Rueger, of lawful age, first being duly sworn upon oath says that he is Senior Vice President - Generation and Chief Nuclear Officer of Pacific Gas and Electric Company; that he has executed this response to the request for additional information on License Amendment Request 01-04, and License Amendment Request 01-05 on behalf of said company with full power and authority to do so; that he is familiar with the content thereof; and that the facts stated therein are true and correct to the best of his knowledge, information, and belief.

Gregoq M' Rueger Senior Vice President- Generationand Chief Nuclear Officer Subscribed and sworn to before me this 14th day of August 2002.

County of San Luis Obispo State of California N~ota~ry Public Commission# 1339380

  • z Notary Public- Califomia San Luis Obispo County) 1**" My Comm Expires Jan 12,2006

Enclosure 1 PG&E Letter DCL-02-095 PG&E Response to NRC Request for Additional Information Regarding License Amendment Request 01-04, "Revision To Technical Specifications 3.9.4 Containment Penetrations" Question 1 In Section 4 of Enclosure 1 to the submittal, you provided new radiologicalconsequence analysis for the control room operatorfollowing the postulated fuel handling accidentinside containment. Providethe unfiltered airin-leakage rate into the controlroom you assumed in your analysis with its technicaljustification.

PG&E Response to Question 1 The unfiltered in-leakage assumed in the analysis is 10 standard cubic feet per minute (scfm). This value is the current Diablo Canyon Power Plant (DCPP) licensing basis and was carried over into this analysis.

The DCPP control room heating, ventilating, and air conditioning envelope is a pressurized volume with a filtered air supply and filtered recirculation. The current design basis unfiltered air in-leakage is 10 scfm and is used to account for the potential introduction of unfiltered outside air due to the ingress and egress of personnel through the control room pressurization boundary due to actions required to support post-accident recovery. This value is consistent with the value recommended by Standard Review Plan (NUREG-0800)

Section 6.4, "Control Room Habitability System," for contributions due to personnel ingress and egress required by plant emergency procedures and recovery actions.

No additional in-leakage is included in the DCPP analysis since the design basis is that the control room is pressurized when in ventilation mode 4. As long as the control room remains at a pressure greater than that of the surrounding areas, net leakage will be in the outward direction. The potential for unfiltered in-leakage from sources of higher pressure than the control room or its ducting is considered low. The design and construction of the DCPP control room ventilation system and positive pressure envelope provide a high level of confidence that there is very little to no in-leakage other than through the in-leakage assigned to ingress/egress associated with event recovery.

Recent testing performed at two STARS plants supports this position. The Palo Verde Nuclear Generating Station (PVNGS) and the Comanche Peak Steam Electric Station (CPSES) both recently completed testing of their control room ventilation systems. The ventilation configurations of these two plants bound the range of control room ventilation configurations of the STARS plants.

The testing performed-at PVNGS and CPSES established, baseline in-leakage rates for both .,;

plants and also conipared multiple testing methods for a6curacy and acceptability. Testing at' both plants included component and tracer gas testing with both methods yielding consistent results. In both cases, the results showed no unfiltered in-leakage into the control room positive pressure envelope.

Enclosure 1 PG&E Letter DCL-02-095 DCPP will use the component test method to verify that control room unfiltered in-leakage is negligible or non-existent. The results of this testing will be factored into any assessment of control room habitability at that time. Currently, plans for component testing are in the process of being developed and DCPP anticipates that testing will be performed after the completion.of the next refueling outage (2R11). The expectation is that this testing will be performed during the spring of 2003.

Question 2 In Section 4 of Enclosure 1 to the submittal, you stated that the values assumed for individual fission product inventories are calculatedbased on 105 percent of full power (3580 MWt) at the end of core life immediately preceding shutdown. Provide the individualfission product inventories assumed.

PG&E Response to Question 2 Shutdown isotopic inventories for the isotopes of interest are summarized below. The inventory listed is for an individual fuel assembly from a core of 193 fuel assemblies operating at 3580 MWt.

Composite Source Isotope term - Ci/assy 1-131 5.057E+05 1-132 7.283E+05 1-133 1.032E+06 1-134 1.165E+06 1-135 9.611E+05 Kr-83m 8.196E+04 Kr-85m 1.901E+05 Kr-85 6.353E+03 Kr-87 3.828E+05 Kr-88 5.416E+05 Kr-89 6.855E+05 Xe-131m 5.661E+03 Xe-133m 3.187E+04 Xe-1 33 9.993E+05 Xe-135m 2.021E+05 Xe-135 2.886E+05 Xe-137 9.140E+05 Xe-138 9.477E+05 2

Enclosure 1 PG&E Letter DCL-02-095 Question 3 Provide the noble gases and iodines activities in the fuel "rodgap prior to fuel movement (100 hour0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> decay period) that is available for release to the watersurroundingthe failed fuel assembly. Also provide the amounts of fission product activities (in curies) releasedto the environment following the postulatedfuel handling accident.

PG&E Response to Question 3 The noble gas and iodine activity assumed in the fuel assembly and released to containment at the time of the event were as follows:

Isotope Activity at 100 Hours After Containment Activity based Shutdown(Ci) on DF200 (Ci) 1-131 3.625E+05 299.0625 1-132 3.042E+05 250.965 1-133 3.783E+04 31.21 1-134 0 0 1-135 2.689E+01 0.0222 Kr-83m 9.554E-08 1.5764E-08 Kr-85m 3.679E-02 0.0060704 Kr-85 6.350E+03 3143.25 Kr-87 0 0 Kr-88 1.350E-05 2.2275E-06 Kr-89 0 0 Xe-1 31m 5.469E+03 902.385 Xe-133m 1.306E+04 2154.9 Xe-1 33 6.914E+05 114081 Xe-1 35m 4.264E+00 0.70356 Xe-1 35 1.327E+03 218.955 Xe-1 37 0 0 Xe-138 0 0 The entire inventory released to containment was assumed to be released to the environment.

3

Enclosure 1 PG&E Letter DCL-02-095 Question 4 Provide the controlroom 6trrnbsphericrelative concentratiohns(X'Q values) used in your new dose calculation performed for the controlroom operator.

PG&E Response to Question 4 The X/Q values used in the LAR 01-04 analysis are:

Atmospheric Dispersion Factors in sec/m__

Control Room' Pressurization Infiltration 0 - 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> 7.05E-05 1.96E-04 8 - 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> 5.38E-05 1.49E-04 24 - 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> 3.91 E-05 1.08E-04 96 - 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> 2.27E-05 6.29E-05 Exclusion Area Boundary (EAB) , 800 meters 0 - 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> 5.29E-04 Low Population Zone (LPZ) , 10,000 meters 0 - 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> 2.20E-05 8 -24 hours 4.75E-06 24 - 96 hours0.00111 days <br />0.0267 hours <br />1.587302e-4 weeks <br />3.6528e-5 months <br /> 1.54E-06 96 - 720 hours0.00833 days <br />0.2 hours <br />0.00119 weeks <br />2.7396e-4 months <br /> 3.40E-07 1 Control Room X/Q values are from FSAR Update Table 15.5-6.

2 The The EAB and LPZ X/Q values are from FSAR Update Table 15.5-3.

4

Enclosure 2 PG&E Letter DCL-02-095 PG&E Response to NRC Request for Additional Information Regarding License Amendment Request 01-05, "Revision to Technical Specification 1.1, Definitions, Dose Equivalent 1-131, and Revised Steam Generator Tube Rupture and Main Steam Line Break Analyses" Question 1 The licensee assumed, among other things, a 10 cfm controlroom unfiltered air in-leakage in control room operatordose calculations for SGTR and MSLB accidentre analyses in license amendment request 01-05. [The staff] will not accept this assumption without verification by a suitable in-leakage test. The controlroom unfiltered airin-leakage is an important parameterin determining control room operator dose following DBAs. The licensee is a member of the STARS group which is developing and testing an integratedtest method for controlroom unfiltered air in-leakage. They are keeping the NRC informed. [The staff asks] if DCPPhas performed any test, or is planning to perform a test, in concert with STARS program. If DCPPis planning a test. what is the schedule and how would it be different from the tests performed at Comanche Peakand Palo Verde? Are Comanche Peak test results available? What is the currentprogramstatus on the development of control room unfiltered in-leakage tests?

Note: In a telephone conference call on July 25, 2002, the NRC staff indicated that PG&E's response to Question 1 for LAR 01-04 would also address the above question for LAR 01-05. The response for Question 1 for LAR 01-04 is repeated below.

PG&E Response to Question I The unfiltered in-leakage assumed in the analysis is 10 standard cubic feet per minute (scfm). This value is the current Diablo Canyon Power Plant (DCPP) licensing basis and was carried over into this analysis.

The DCPP control room heating, ventilating, and air conditioning envelope is a pressurized volume with a filtered air supp!y and filtered recirculation. The current design basis unfiltered air in-leakage is 10 scfm and is used to account for the potential introduction of unfiltered outside air due to the ingress and egress of personnel through the control room pressurization boundary due to actions required to support post accident recovery. This value is consistent with the value recommended by Standard Review Plan (NUREG-0800) Section 6.4, "Control Room Habitability System," for contributions due to personnel ingress and egress required by plant emergency procedures and recovery actions.

No additional in-leakage is included in the DCPP analysis since the design basis is that the control room is pressurized when in ventilation mode 4., As long as the control room remains at a pressure greater than that of the surrounding areas, net leakage will be in the outward direction. The potential for unfiltered in-leakage from sources of higher pressure than the control room or its ducting is considered low. The design and I

Enclosure 2 PG&E Letter DCL-02-095 construction of the DCPP control room ventilation system and positive pressure envelope provide a high level of confidence that there is very little to no in-leakage other than through the in-leakage assigned to ingress/egress associated with event recovery.

Recent testing performed at two STARS plants supports this position. The Palo Verde Nuclear Generating Station (PVNGS) and the Comanche Peak Steam Electric Station (CPSES) both recently completed testing of their control room ventilation systems. The ventilation configurations of these two plants bound the range of control room ventilation configurations of the STARS plants.

The testing performed at PVNGS and CPSES established baseline in-leakage rates for both plants and also compared multiple testing methods for accuracy and acceptability.

Testing at both plants included component and tracer gas testing with both methods yielding consistent results. In both cases, the results showed no unfiltered in-leakage into the control room positive pressure envelope.

DCPP will use the component test method to verify that control room unfiltered in-leakage is negligible or non-existent. The results of this testing will be factored into any assessment of control room habitability at that time. Currently, plans for component testing are in the process of being developed and DCPP anticipates that testing will be performed after the completion of the next refueling outage (2R11). The expectation is that this testing will be performed during the spring of 2003.

2