ML17191B459
| ML17191B459 | |
| Person / Time | |
|---|---|
| Site: | Dresden  |
| Issue date: | 09/23/1999 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML17191B458 | List: |
| References | |
| NUDOCS 9910040014 | |
| Download: ML17191B459 (4) | |
Text
\\' r UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 2055$--0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 173 TO FACILITY OPERATING LICENSE NO. DPR-19 AND AMENDMENT NO. 169 TO FACILITY OPERATING LICENSE NO. DPR-25 COMMONWEAL TH EDISON COMPANY DRESDEN NUCLEAR POWER STATION. UNITS 2 AND 3 DOCKET NOS, 50-237 AND 50-249
1.0 INTRODUCTION
By lett~r dated May 3, 1999, as supplemented by letter dated September 10, 1999, the Commonwealth Edison Company (ComEd, the licensee) proposed changes to the Dresden Nuclear Power Station, Units 2 and 3, Technical Specifications. (TSs). The requested changes will relocate TS 3/4.6.1, "Chemistry," and the associated bases from the TS to the Updated Final Safety Analysis Report (UFSAR). The September 10, 1999, submittal provided clarifying information that did not change the initial proposed no significant hazards consideration determination.
The licensee intends to inject noble metal compounds into the reactor coolant to prevent crack initiation arid to mitigate any existing crack growth in the reactor vessel surfaces, internal components and piping due to intergranular stress corrosion cracking. The noble metal solutions are expected to temporarily increase reactor coolant conductivity and pH levels which will later be reduced to normal pre-application operation levels by the reactor water cleanup system. The noble metal injection will be performed in Mode 3.
2.0 BACKGROUND
Section 182a of the Atomic Energy Act requires applicants for nuclear power plant operating
. licenses to state the TSs to be included as part of the license. The Commission's regulatory requirements related to the content of the TSs are set forth in 10 CFR 50.36. That regulation requires the TSs to include items in five specific categories, including (1) safety limits, limiting safety system settings and limiting control settings; (2) limiting conditions for operation; (3) surveillance requirements; (4) design features; and (5) administrative controls. However, the regulation does not specify the particular requirements to be included in a plant's TSs.
The four criteria defined in 1 O CFR 50.36 to be used in determining whether a particular limiting condition for operation (LCO) and related surveillance is required to be included in the TSs are as follows:
(1) installed instrumentation that is used to detect, and indicate in the control room a significant abnormal degradation of the reactor coolant pressure boundary; 9910040014 990923 PDR ADOCK 05000237.
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.I (2) a process variable, design feature, or operating restriction that is an initial condition of a design basis accident or transient analysis that either assumes the failure of or presents a challenge to the integrity of a fission product barrier; (3) a structure, system, or component that is part of the primary success path and which functions or actuates to mitigate a design basis accident or transient that either assumes t~e failure of or presents a challenge to the integrity of a fission product barrier; and (4) a structure, system, or component which operating experience or probabilistic safety assessment has shown to be significant to public health and safety.
As a result, existing TS requirements which fall within or satisfy any of the criteria in 1 O CFR 50.36 must be retained in the TSs, while those TS requirements that do not fall within or satisfy these criteria may be relocated to other licensee controlled documents.
3.0 EVALUATION The licensee has proposed relocating TS 3/4.6.I; "Chemistry," and the associated bases to licensee controlled documents. This TS contains requirements for reactor coolant chloride concentration, conductivity, and pH. The four criteria of 1 O CFR 50.36 (ire addressed below:
(1)
The reactor coolant chemistry limits as specified in TS 3/4.6.I are not used to detect and indicate in the control room a significant abnormal degradation of the reactor coolant pressure boundary. The TS provides limits on particular chemical properties of the primary coolant, and surveillance requirements to monitor these properties to ensure that degradation of the reactor coolant pressure boundary is not exacerbated by poor chemistry condition. However, degradation of the reactor coolant pressure boundary is a long-term process. Other regulations and TS provide direct means to monitor and correct the degradation of the reactor coolant pressure boundary; for example, in-service inspection and primary coolant leakage limits.
(2)
Chemistry parameters are not used as an initial condition of a Design Basis Accident or Transient Analysis that either assumes the failure of or presents a challenge to the integrity of a fission product barrier.
(3)
Reactor coolant conductivity, chloride concentration, and pH are not used as part of the primary success path which functions or actuates to mitigate a Design Basis Accident or Transient.
(4)
Operating experiences or probabilistic safety assessments have not shown chemistry parameters to be significant to pubic health and safety.
In their May 3, 1999 submittal, the licensee proposed to relocate the Chemistry TS to the UFSAR and to plant procedures controlled by 10 CFR 50.59. Initially, the staff could not establish that all of the TS being relocated would be relocated either to the UFSAR or to
.. procedures nor could the staff establish that changes to the information being relocated to procedures would be controlled by 10 CFR 50.59. In order to resolve this issue, the licensee committed to relocate all of the TS requirements and bases removed by this Amendment to the UFSAR. License condition number three of this Amendment establishes this commitment as a regulatory requirement. Any changes to these requirements will be controlled by the provisions of 1 O CFR 50.59 and any unreviewed safety questions must obtain NRC review and approval.
The September 10, 1999, Com Ed submittal described the water chemistry monitoring and controls that they use during normal operation and the additional monitoring and controls that will be in place during noble metal chemical injection. The staff reviewed these and found them to be acceptable.
The relocation of Section 3/4.6.I from the TSs to the UFSAR will continue to provide adequate assurance that concentrations in excess of the limits will be detected and addressed. The
- proposed TS is consistent with NUREG-1433, "Standard Technical Specifications, _General Electric Plants, BWR/4, Revision.1."
- In conclusion, the above relocated requirements are not required to be in the TSs under 10 CFR 50.36 or §182a of the Atomic Energy Act, and are not required to obviate the possibility of an abnormal situation or event giving rise to an immediate threat to the pubic health and safety. In addition, the staff finds that sufficient regulatory controls exist under 10 CFR 50.59 to assure continued protection of the public health and safety.
Accordingly, the staff has concluded that these requirements may be relocated from the TSs to the licensee's UFSAR.
4.0 STATE CONSULTATION
In accordance with the Commission's regulations, the Illinois State official was notified of the proposed issuance of the amendments. The State officialhad no comments.
5.0 ENVIRONMENTAL CONSIDERATION
The amendments change a requirement with respect to the installation or use of a facility
- component located within the restricted area as defined in 10 CFR Part 20 and change surveillance requirements. The NRC staff has determined that the amendments involve no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The* Commission has previously issued a proposed finding that the amendments involve no significant hazards consideration, and there has been no public comment on such finding (64 FR 43768). Accordingly, the amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared
- in connection with the issuance of the amendments.
6.0 CONCLUSION
The Commission has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendments will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor: L. Rossbach Date: September 23, 1999
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