ML040640637
| ML040640637 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 03/01/2004 |
| From: | Vanderheyden G Constellation Generation Group |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| nxp, tjb2 | |
| Download: ML040640637 (6) | |
Text
George Vanderheyden 1650 Calvert Cliffs Parkway Vice President Lusby, Maryland 20657 Calvert Cliffs Nuclear Power Plant 410 495-4455 Constellation Generation Group, LLC 410 495-3500 Fax Constellation Energy Group March 1, 2004 U. S. Nuclear Regulatory Commission Washington, DC 20555 ATTENTION:
Document Control Desk
SUBJECT:
Calvert Cliffs Nuclear Power Plant Unit Nos. I & 2; Docket Nos. 50-317 & 50-318 Response to Request for Additional Information Concerning the License Amendment Request to Revise the Refueling Operations Section of the Technical Specifications This letter provides the information we agreed to provide you during Reference (a). This information supports and/or clarifies the information provided in Reference (b). This information does not affect the No Significant Hazards Consideration Determination or the Environmental Impact Review of Reference (b).
Requested Information:
- 1. Please provide the current analysis for control room doses.
CCNPP Response:
In accordance with TMI Item III.D.3.4, "Control Room Habitability," we have committed to ensure Control Room Operators will be adequately protected against the effects of accidental releases of toxic and radioactive gases and that the nuclear power plant can be safely operated or shut down under design basis accident conditions (Criterion 19, "Control Room," of Appendix A, "General Design Criteria for Nuclear Power Plants," to 10 CFR Part 50). The Nuclear Regulatory Commission (NRC) concluded that the Control Room habitability systems are acceptable, and that the systems will provide safe, habitable conditions within the Control Room under both normal and accident radiation and toxic gas conditions, including loss-of-coolant accidents (LOCAs) (Reference c).
This conclusion was predicated upon commitments to install a shield wall to prevent any streaming through the pipe chase into the Control Room from below, and to ensure sufficient self-contained breathing apparatus (SCBAs) are available to the Control Room personnel to meet the requirements of Regulatory Guide 1.78.
Subsequently, we suspended the Control Room habitability thyroid dose calculation pending the issuance of revised source terms for the evaluation of Control Room habitability from the NRC. In an
Document Control Desk March 1, 2004 Page 2 interim engineering analysis, it was concluded that the post-LOCA thyroid dose will be maintained below the 30-day limit of 30 rem, if planned protective measures (SCBAs) are implemented within 32 minutes. The use of SCBAs and potassium iodide (KI) tablets by the Control Room Operators following an accident is consistent with Calvert Cliffs' Emergency Response Plan. The analysis noted that there are sufficient SCBAs staged in the Control Room to provide protection to all Control Room Operators following an accident and that additional SCBAs are staged elsewhere onsite for operators coming on-shift.
Control Room habitability was analyzed in a similar manner as the maximum hypothetical accident analysis present in Updated Final Safety Analysis Report (UFSAR) Section 14.24; however, the only source of radiation assumed in the interim Control Room habitability analysis was that resulting from the maximum allowable containment leakage (per Regulatory Guide 1.4).
In addition to the assumptions used in the maximum hypothetical accident analysis, the interim Control Room habitability analysis was based upon the assumptions provided in Reference (d). The NRC concurred with the adequacy of these interim compensatory measures (Reference e). Their acceptance was predicated upon our commitment to submit the final design.
In a licensing action to allow the containment personnel air lock to be open during fuel movement and core alterations, we expanded the scope of the Control Room habitability interim analysis to apply to a fuel handling accident inside Containment. The analysis showed that the operator thyroid dose can be reduced to meet the General Design Criteria (GDC) 19 limits following a fuel handling accident while the Containment is open as long as the additional protective measures (SCBAs) are taken within 82 minutes. The NRC approved this licensing action in Reference (f).
The current analysis for the fuel handling incident presented in Calvert Cliffs UFSAR, Section 14.18, "Fuel Handling Incident," assumes that the personnel air lock and the containment outage door (COD) are open for the duration of the incident and one volume of unfiltered containment atmosphere containing activity is released from Containment every two hours. The license amendment request to have the COD open during fuel handling and core alterations (Reference g) was reviewed and approved by the NRC staff (Reference h). The analysis showed that the operator thyroid dose can be reduced to meet the GDC 19 limits following a fuel handling accident while the Containment is open as long as the additional protective measures (SCBAs) are taken with 82 minutes.
In our response to NRC Generic Letter 2003-01 (Reference i) we described our compensatory measures to demonstrate Control Room habitability and the corrective actions that will be taken to retire these compensatory measures. Our evaluation has determined that a reanalysis of applicable UFSAR, Chapter 14 accidents using alternate source term per Regulatory Guide 1.183, combined with targeted sealing of the Control Room envelope, will be needed to retire the interim compensatory measures.
A sensitivity study is being performed on six accidents to determine possible corrective actions necessary to achieve the required total effective dose equivalent of 5 Rem to the Control Room operators without compensatory measures.
Our current plan calls for completing the formal reanalysis of the applicable accidents using alternate source term and submittal of a license amendment request to the NRC by November 30, 2004. Associated modifications will be implemented once the submitted analyses are approved, with a goal of completing the implementation by December 2005.
If any of the modifications require an outage, our goal is to complete implementation by June 2006. Possible analytical input changes being considered include: reducing overall Containment leakage (La) and adding filtration to the refueling water tank vent line, taking
Document Control Desk March 1, 2004 Page 3 additional credit for various Technical Specification charcoal/high efficiency particulate air filters, and reducing in-leakage pathways into the Auxiliary Building during accident scenarios.
- 2. Constellation Energy should address the proposed amendment request in terms of the requirements of Draft GDCs 70 and 17 and explain how the proposed changes assure that the requirements of these Draft GDCs are met.
CCNPP Response:
Draft Criterion 70 - Control of Releases of Radioactivity to the Environment (Category B) states that the facility design shall include those means necessary to maintain control over the plant radioactive effluents, whether gaseous, liquid, or solid. Appropriate holdup capacity shall be provided for retention of gaseous, liquid, or solid effluents, particularly where unfavorable environmental conditions can be expected to require operational limitations upon the release of radioactive effluents to the environment. In all cases, the design for radioactivity control shall be justified, (a) on the basis of 10 CFR Part 20 requirements for normal operations and for any transient situation that might reasonably be anticipated to occur, and (b) on the basis of 10 CFR Part 100 dosage level guidelines for potential reactor accidents of exceedingly low probability of occurrence except that reduction of the recommended dosage levels may be required where high population densities or very large cities can be affected by the radioactive effluents.
Although the wording of the draft GDC 70 may appear vague, we know it refers to the operation of the radioactive waste processing system. Our response to the draft GDC (Reference j) and the final GDC (GDC 60) refers specifically to radioactive waste processing systems.
The proposed changes do not make any changes to the radioactive waste processing systems or how they will operate. Therefore, the proposed changes have no impact on how the requirements of Draft GDC 70 are met.
As stated in our response to Draft GDC 70 (Reference j), the radioactive waste processing system collects, segregates, processes, and disposes of radioactive solids, liquids, and gases in such a manner as to comply with 10 CFR Part 20.
Solid wastes are processed in a batch manner for off-site disposal. Processed liquid wastes and gaseous wastes released to the environment will be monitored and discharged with suitable dilution to assure tolerable activity levels on the site and at the site boundary. Holdup capacity in the reactor coolant waste processing system is 360,000 gallons; the miscellaneous waste processing system has a storage capacity of 8,000 gallons. All liquid wastes are sampled to establish their acceptability for release.
The contents of the waste gas decay tanks will be sampled, and a release rate established consistent with the prevailing environmental conditions.
A capability is provided for 60-day holdup of waste gas. In-line monitoring will provide a continuous check on the release of activity.
Under incident conditions, radioactive gaseous effluents that may be released into enclosed areas are collected by the ventilation systems and discharged to the plant vent. Permanently installed area radiation detectors and the plant vent radioactivity detectors are used to monitor the discharge levels to the environment. In addition, portable radiation monitors are available on site
Document Control Desk March 1, 2004 Page 4 for supplemental surveys. The releases from these incidents have been calculated to be less than 10 CFR Part 100 guidelines.
Draft Criterion 17 - Monitoring Radioactivity Releases (Category B) states that means shall be provided for monitoring the containment atmosphere, the facility effluent discharge paths, and the facility environs for radioactivity that could be released from normal operations, from anticipated transients, and from accident conditions.
The proposed Technical Specification change will allow for containment penetrations to be opened under administrative control.
Means are provided for monitoring the containment atmosphere, which include continuous air monitoring. High radiation inside Containment will also cause the containment purge valves to automatically close and would notify the operators that containment closure is needed. The current analysis for the fuel handling incident presented in the Calvert Cliffs UFSAR, Section 14.18, "Fuel Handling Incident," assumes that the Containment remains open following the incident and one volume of containment atmosphere containing activity is released from Containment unfiltered. Therefore, the monitoring of the containment atmosphere provides additional assurance that the actual offsite doses will be less than the current analysis.
Document Control Desk March 1, 2004 Page 5 Should you have questions regarding this matter, we will be pleased to them with you.
Very STATE OF MARYLAND COUNTY OF CALVERT
- TO WIT:
I, George Vanderheyden, being duly sworn, state that I am Vice President - Calvert Cliffs Nuclear Power Plant, Inc. (CCNPP), and that I am duly authorized to execute and file this License Amendment Request on behalf of CCNPP. To the best of my knowledge and belief, the statements contained in this document are true and correct. To the extent that these statements are not based on y personal knowledge, they are based upon information provided by other CCNPP employees and/or c nsultants. Such information has been reviewed in accordance with company practice and I believe it to e reliable.
Subscribed and sworn before me a Notary Public in and for the State of Maryland and County of 5
this __
_ day of..Ž94
, 2004.
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WITNESS my Hand and Notarial Seal:
My Commission Expires:
6122/01 L'za Notary PufI m gq a4 aD 007 t
Mite GV/DJM/bjd
Document Control Desk March 1, 2004 Page 6
REFERENCES:
(a)
Telephone Conference between Ms. D. J. Mitchell, et.al. (CCNPP) and Mr. G. Vissing, et.al.
(NRC), dated December 8, 2003, same subject (b)
Letter from Mr. P. E. Katz (CCNPP) to Document Control Desk (NRC), dated August 6, 2002, License Amendment Request: Revisions to the Refueling Operations Section of the Technical Specifications (c)
Letter from Mr. R. A. Clark (NRC) to Mr. A. E. Lundvall, Jr. (BGE), dated September 3, 1982, Review of NUREG-0737 Item III.D.3.4, Control Room Habitability (d)
Letter from Mr. R. E. Denton (BG&E) to Document Control Desk (NRC), dated May 6, 1993, Control Room Habitability - Interim Engineering Analysis for Thyroid Dose (e)
Letter from Mr. D. G. McDonald, Jr. (NRC) to Mr. R. E. Denton (BGE), dated June 22 1995, Control Room Habitability Interim Analysis for Thyroid Dose (f)
Letter from Mr. D. G. McDonald (NRC) to Mr. R. E. Denton (BG&E), dated August 31, 1994, Issuance of Amendments for Calvert Cliffs Nuclear Power Plant (License Amendment Nos. 194 and 171)
(g)
Letter from Mr. C. H. Cruse (BGE) to Document Control Desk (NRC), dated January 27, 2000, License Amendment Request:
Modification of Containment Closure During Core Alterations/Fuel Handling and Loss of Shutdown Cooling (h)
Letter from Ms. D. Skay (NRC) to Mr. C. H. Cruse (CCNPP), dated March 12, 2001, Calvert Cliffs Nuclear Power Plant, Unit Nos. I and 2 - Amendment RE: Containment Closure (TAC Nos. MA8063 and MB8064)
(i)
Letter from Mr. G. Vanderheyden (CCNPP) to Document Control Desk (NRC), dated December 5, 2003, Response to NRC Generic Letter 2003-01, Control Room Habitability (j)
Letter from Mr. J. W. Gore, Jr. (BG&E) to Dr. P. A. Morris (US AEC), dated January 4, 1971, Amendment No. 11 cc:
J. Petro, Esquire H. J. Miller, NRC J. E. Silberg, Esquire Resident Inspector, NRC R. J. Laufer, NRC R. I. McLean, DNR G. S. Vissing, NRC