ML18153B925

Proposed Tech Specs,Replacing Portion of Control Rod Drop Time Test Frequency Requirement Associated W/Rcs Integrity

ML18153B925
Person / Time
Site:	Surry
Issue date:	10/12/1989
From:	VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:
Shared Package
ML18153B924	List: ML18153B923 ML18153B925
References
NUDOCS 8910170228
Download: ML18153B925 (5)

Text

ATTACHMENT 1 PROPOSED TECHNICAL SPECIFICATION CHANGES J

TABLE 4.1-2A MINIMUM FREQUENCY FOR EQUIPMENT TESTS FSAR Section Description Tus1 Frequency Reference

1. Control Rod Assemblies Rod drop times of all Prior to reactor criticality: 7 full length rods at a. For all rods following each removal hot conditions of the reactor vessel head,

b. For specially affected individual rods following any maintenance on or modi-fication to the control rod drive system which could affect the drop time of those specific rods, and C. Each refueling shutdown.

2. Control Rod Assemblies Partial movement of Every 2 weeks 7 all rods

3. Refueling Water Chemical Functional Each refueling shutdown 6 Addition Tank

4. Pressurizer Safety Valves Setpoint Per TS 4.0.3 4

5. Main Steam Safety Valves Setpoint Per TS 4.0.3 10

6. Containment Isolation Trip *Functional Each refueling shutdown 5

7. Refueling System Interlocks *Functional Prior to refueling 9.12

8. Service Water System *Functional Each refueling shutdown 9.9

9. Fire Protection Pump and Functional Monthly 9.10 Power Supply 1 0. Primary System Leakage *Evaluate Daily 4

11. Diesel Fuel Supply *Fuel Inventory 5 days/week 8.5

12. Boric Acid Piping Heat *Operational Monthly 9.1 Tracing Circuits

13. Main Steam Line Trip Functional Before each startup (TS 4.7) 10 Valves (Full Closure)

-I (J) f",

I CD 0-

ATTACHMENT 2 DISCUSSION AND SIGNIFICANT HAZARDS CONSIDERATION EVALUATION

DISCUSSION In order to clarify the purpose and schedule of measuring control rod drop times, wording similar to that of the Westinghouse Standard Technical Specification (STS) of surveillance requirements for rod drop performance is being submitted in lieu of the present description. Currently, control rod drop time testing is required after removal of the reactor vessel head and after any control rod specific maintenance. However, another literal interpretation of Item 1 from Table 4.1-2A could be that Control Rod Drop Time Tests should be conducted (unnecessarily) due to any "breach of Reactor Coolant System integrity" such as maintenance on a loop stop valve or opening of a PORV. This is not our understanding of the intent of the Technical Specification since there is no statement in the bases to such an effect nor is this consistent with the STS. A review of the Updated Final Safety Analysis Report (UFSAR), the original FSAR and associated NRC Safety Evaluation Report also yielded no indication that testing according to this expansive interpretation was intended. A review of initial plant licensing identified only one related question regarding Control Rod Drop Mechanism (CROM) failure experience due to manufacture and* installation. Operational testing requirements were not addressed by the question or the response. Subsequent industry experience with CRDMs has established the operational testing frequency specified by the STS.

Thus, the proposed change incorporates STS terminology in order to clarify the intent of the Technical Specification.

10 CFR 50.92 SIGNIFICANT HAZARDS CONSIDERATION EVALUATION The operation of Surry Power Station in accordance with the proposed amendment would not:

(1) Involve a significant *increase the probability or consequences of an accident previously evaluated. Control rod drop time testing is performed to identify potential precursors to a control rod drive mechanism (CROM) failure or a stuck rod. As such, clarifying the frequency of such testing to be based upon activities which may directly affect control rod drop times does not increase the probability of occurence of a CROM failure or a stuck rod event.

Specifically, there is no basis or referenced supporting analysis of any situational requirements in the Technical Specifications or the UFSAR upon which the frequency of control rod drop time testing was determined. Furthermore, the proposed change is consistent with Standard Technical Specifications which bases control rod drop time test frequency on activities which may directly affect the CROM.

Likewise, the UFSAR stuck rod analysis is not affected by the proposed clarification to frequency of control rod drop time testing.

There is no increase in the consequences of an UFSAR evaluated accident; or (2) Create the possibility of a new or different kind of accident from any accident previously evaluated. Inasmuch as the proposed change is a clarification to reflect existing surveillance practice which will remain intact, no change in operation or surveillance is being made, therefore, no new accident or malfunction scenarios are introduced by the change. As noted above, no accident consequences other than that presently evaluated in the UFSAR is introduced by this change, nor does this change affect any accident analysis assumption; or (3) Involve a significant reduction in a margin of safety. Control rod assembly drop time requirements are unchanged by this proposed technical specification and remain consistent with safety analysis assumptions. As noted above, there is no stated basis or referenced supporting analysis in the Technical Specifications or the UFSAR which establishes the frequency for control rod drop time testing.

The proposed change would clarify testing to be based on activities which may directly affect control rod operability consistent with Standard Technical Specifications.

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