ML20127P107

Advises That Util 850607 Submittal Re Draft Tech Specs for Control Rod Operability Acceptable Provided That Listed Changes Made.Confirmatory Submittal by Licensee of Revised Draft Tech Specs Should Be Provided Prior to Restart

ML20127P107
Person / Time
Site:	Fort Saint Vrain
Issue date:	06/21/1985
From:	King T Office of Nuclear Reactor Regulation
To:	Butcher E Office of Nuclear Reactor Regulation
Shared Package
ML20127P112	List: ML20127P107 ML20128L681
References
NUDOCS 8507020310
Download: ML20127P107 (6)

Text

-. .. ._ - . - . . _ . _ _.. _ _ .

jog

[f

+ UNITED STATES

+

, g NUCLEAR REGULATORY COMMISSION I

r,, -j WASHINGTON, D C.20555

1. June 21,1985 I

l MEMORANDUM FOR: Edward J. Butcher, Jr., Acting Chief, -'

l j Operating Reactors Branch #3 )

Division of Licensing, NRR FROM: Thomas L. King, Chief Advanced Reactors Group Division of Safety Technology, NRR

SUBJECT:

REVIEW OF DRAFT FORT ST. VRAIN TECHNICAL SPECIFICATIONS FOR CONTROL RODS I

4 Public Service Co. of Colorado (PSC), in letter P-85180, dated June 7, 1985, provided the NRC with draft Technical Specifications regarding Fort St. Vrain (FSV) control rod operability. PSC intends to use these draft Technical Specifications as the basis for developing procedures prior to reactor startup for. operation of the control rods until such time as a formal change to the Technical Specifications can be made and implemented. As part of our 4

providing technical assistance to Region IV on the review of the FSV Technical Specifications upgrade program we have reviewed the June 7, 1985 PSC submittal. This review included discussions with and input from appropriate Region IV and NRR personnel as well as discussions on June 17, 1985 and June 19, 1985 with PSC on specific issues associated with their

. submittal. As a result of our review and the above discussions we consider the June 7, 1985 PSC submittal acceptable provided the following changes are made:

1. Page 3/4.1-2:

i a) Action statement D should be changed to state that the provisions of 3.0.6 are not applicable only when in the Startup, Low Power or Power Operation modes. When entering the Startup mode from Shutdown 3.0.6 should be applicable. This will require that all control rods be operable when starting up which, beside being good operating practice, will eliminate any potential for abusing this LCO by changing back and forth from the Startup to Shutdown modes to gain additional 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> periods for repair. Operation for 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> with a single inoperable rod is considered acceptable because the reactivity requirements associated with_the control rod system are such that the plant can be shutdown with a single rod fully withdrawn and the backup Reserve Shutdown System is available to supply additional negative reactivity, if needed. ,

Yh i

's

, fi ,

\. b) Surveillance Requirement 4.1.1-A.1 - Parts (a) and (b) of this t ,. surveillance requirement should be combined and should read as "follows: ,

"With one or more CRD motor temperature (s) greater than 215'F the motor temperature of all CRDs whose motor temperatures are greater

'~

than 215'F shall be recorded and a partial scram test as described in Specification 4.1.1-B shall be performed on the highest temperature control rod pair at least once per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. A report on the partial scram test results and the maximum daily temperature of those control rods with motor temperatures above 215 F shall be provided to the NRC,at least once every 30 days."

This change is needed to implement surveillance on those rods above their original qualification temperature and to reflect discussions and agreements with PSC on May 3, 1985.

c) Surveillance requirement 4.1.1-A.1.C - Should be renumbered to "b." -The bases for this requirement should make it clear that the

" engineering evaluation" must be completed within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> or less to comply with the 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> surveillance interval.

d) Surveillance requirement 4.1.1-A.2 - Should be split into two parts as follows:

- .Part I should specify that the purge flow to each CRD mechanism is verified by monitoring flow in each purge line subheader. The basis for this surveillance should state that the valves irithe individual CRD purge lines are sealed in the

! open positiori ard; therefore, their position is controlled via administrative precedures. A specified value for minimum subheader flow indication will be determined after some operating experience with the flow instrumentation is gained.

- Part 2 should specify that P3 purge flow is verified free of condensed water by moniterf 4 .he water content of the knockout pots. PSC shde W ';de in this surveillance l- 3 requirement the speciife f.ht m required on the knockout pots j ';i to verify their operation.

2. Page5/4.1-5:

a) ' Action statement E should be changed to state that the provisions e of 3.0.6 are not applicable only when in the Startup, Low Power or Power Operation modes. When entering the Startup mode from Shutdown 3.0.6 should be applicable. This will then require all rod position instrumentation be operable when starting up which -

/ will ensure redundant instrumentation to accommodate a rod position indication instrument failure during operation.

7

, , 4 b) Surveillance requirement 4.1.2-A - The last sentence of this paragraph contains the words: "unless the analog indication can be proven to be accurate and OPERABLE by another means." PSC should either explain in the basis for this requirement what is an acceptable "other means" or remove this statement from the surveillance. ~

3. Page 3/4.1-6:

The basis for paragraph C should state that operating procedures require a control rod not be driven in beyond a zero indication on the analog and digital position instrumentation. This combined with the accuracy requirement contained in the subject paragraph will then prevent rod over-travel which could damage the analog or digital system potentiometers.

4. Page 3/4.1-7:

An additional requirement should be added to Surveillance 4.1.3 similar to paragraph C on page 3/4.1-6. This will then help ensure that when in the Shutdown and Refueling modes, control rod position indication accuracy is maintained sufficient to prevent damage to the analog and digital potentiometers due to rod over-travel.

5. Page 3/4.1-13:

In LC0 3.1.5-B.2 reference is made to FSAR Section 14.2.2.6 for the requirements associated with the maximum rod worth at full power.

Reference in an LC0 to a section of the FSAR is not acceptable because of the licensee's ability to change the FSAR without prior NRC approval.

We would prefer PSC summarize in the LC0 the appropriate requirements affecting maximum rod worth or if this would be too cumbersome to reference an appropriate section of an NRC controlled document, such as an SER.

6. Page 3/4.1-14:

Surveillance 4.1.5-B - The basis for this surveillance should explain the difference and acceptability in required accuracy between control rod groups 4A/4D and all other groups (i.e., 4A and 4D are in 5 column regions, versus 7 column regions for all other groups, and are of low worth).

b* <

7. Page 3/4.1-15:

Action statement B should be split into two parts as follows:

- Part I should address the situation associated with entering the i Shutdown mode from the Startup, Low Power or Power Operation modes (i.e., scram or reactor shutdown). The action should require within one hour the insertion of any control rods not fully inserted and the actuation of the reserve shutdown system if more than two control rods cannot be fully inserted. The actuation of the reserve shutdown system can be limited to those positions associated with control rods which cannot be fully inserted beyond the allowable two. The intent of this action statement is to require a rapid assessment of control rod position, based upon rod position indication instrumentation, and to take immediate corrective action based upon this indication. A delay of 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> while a shutdown margin calculation is made is unacceptable.

- Part 2 should address the situation associated with having been in the Shutdown or Refueling mode for an extended period of time.

~i This action can be along the lines of that proposed by PSC for the subject action since the withdraw of control rods is done in a fashion (controlled via LC0 3.1.6) such that it is highly unlikely .

the shutdown margin requirement would be exceeded even if the rods could not be reinserted.

8. Page 3/4.1-16:

Surveillance 4.1.6-C - It should be clarified that this surveillance requirement applies to control rod drive assemblies removed from the reactor for refueling, maintenance or repair.

9. Page 3/4.1-17:

Consistent terminology should be used in the LCO, action statement and surveillance statement as follows:

a) In the action and surveillance statements the term " reactivity temperature change" should be replaced with the term " reactivity change."

b) In the survalitcnce statement the term " fuel temperature change" should be replaced with the defined term " CORE AVERAGE TEMPERATURE."

-e~-- - - - . . - - _ _ _ - . - _ , , , . , , , , _ ,,____ _ _ , _ , . _ _ . , , , . _ _ . . , . , , , , _ _ . _ _ _ . _ _ _ _ _ _ . , . _ _ _ , _ _ , _ . _ _ _

w -we -. . . 7

.. 10. Page 3/4.1-18:

a) PSC should commit to update the FSV FSAR to include the analysis which provides the basis for action statements A and B (i.e.,

provide the basis for being able to shutdown the plant.with one or two Reserve Shutdown System units inoperable).

b) Action statemen.t C should be changed to state that the provisions of 3.0.6 are not applicable only when in the Startup, Low Power or Power Operation modes. When entering the Startup mode from Shutdown 3.0.6 should be applicable. This will then require all Reserve Shutdown System units be operable when starting up which, besides being good operating practice, will eliminate any potential for abusing this LC0 by changing back and forth from the Startup td Shutdown modes to gain additional 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> periods for repair. . Operation with two reserve shutdown units inoperable for up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> is consistent with the existing FSV Technical Specifications and is considered acceptable because the reactivity associated with 35 of 37 units of the system operable is sufficient to shutdown the plant.

11. Page 3/4.1-19:

a) In surveillance requirement 4.1.8-C.3 replace the term

" Functionally testing" with the defined term "Perfonning a CHANNEL FUNCTIONAL TEST of."

b) In surveillance requirement 4.1.8-E replace the word " moisture" with the word " water" for consistency and add at the end of this paragraph a reference to surveillance 4.1.9-D.4 for the requirements associated with verifying reserve shutdown unit operability after being exposed to condensed water.

12. Page 3/4.1-21:

a) In surveillance 4.1.9-D.1 the last sentence should be deleted with its requirements included in the appropriate surveillance procedure.

b) In surveillance 4.1.9-D.2 replace the word " Calibrating" with the defined term " Performing a CHANNEL CALIBRATION of."

c) In surveillance 4.1.9-D.3 the requirement for visual examination of the pipe sections should be expanded to state what is to be looked for (i.e., to ensure that there is no corrosion or other obstruction which could inhibit the motion of the absorber balls into the core and that the other reconnected items are capable of performing -

theirfunctions).

i i

O, d) Comment 11(b) above applies to surveillance 4.1.9-E.

To ensure the above changes are satisfactorily implemented a confirmatory submittal by the licensee of revised draft Technical Specifications for control rods, incorporating the above comments, should be provided prior to restart. It should be noted here that several of the above comments also affect the commitments presented in Attachment I to PSC letter P-85199, dated June 14, 1985. This PSC letter should be modified where necessary to be consistent with the above comments.

If you have any questions on the at,ove please contact me at FTS 492-7347.

Thomas L. King, Chie Advanced Reactors Group Division of Safety Technology, NRR cc: K. Heitner, DL G. Lainas, DL J. T. Beard, DL T. Speis, DST, R. Ireland, Rg. IV P. Wagner, Rg. IV

.