ML20245C997
| ML20245C997 | |
| Person / Time | |
|---|---|
| Site: | Duane Arnold  |
| Issue date: | 10/29/1987 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20245C990 | List: |
| References | |
| NUDOCS 8711040285 | |
| Download: ML20245C997 (3) | |
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. UNITED STATES
. g-NUCLEAR REGULATORY COYMISS!ON 7.
E' WASHINGTON, D. C. 20555 '
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SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION SUPPORTING AMENDMENT NO.147 TO FACILITY OPERATING LICENSE N0. DPR-49 IOWA ELECTRIC LIGHT AND POWER COMPANY CENTRAL IOWA POWER COOPERATIVE CORN BELT POWER COOPERATIVE DUANE ARNOLD ENERGY CENTER DOCKET N0. 50-331
- 1. 0 INTRODUCTION LBy letter dated October 17, 1984, as supplemented April 30, 1986, Iowa Electric Light and Power Company (IELP/ licensee) requested changes to the Technical Specifications (TSs) of the Duane Arnold Energy Center (OAEC).
The changes to TSs 3.5.H and 4.5.H are concerned with the maintenance of filled discharge piping from the Core Spray (CS), Low Pressure Coolant Injection (LPCI), High Pressure Coolant Injection (HPCI), and Reactor Core Isolation Cooling (RCIC) Systems.
Revisions were also proposed for Bases 3.5.H.
The proposed action statements would direct operator action in the event the Limiting Condition for Operation (LCO) could not be met.
Previous action statements did not provide this guidance.
2.0 EVALUATION The present TS requires that the discharge piping of the HPCI, RCIC, LPCI, and C$ systems be full to the last block valve when operability of these systems is required.
This minimizes the potential for water hammer when the systems are started and may be accomplished by keep-fill systems.
NUREG-0927, Rev. 1, states that a jockey pump or a storage tank at a higher elevation than the lines of concern may be considered to be adequate for a keep-fill system.
By letter dated October 17, 1984, the licensee proposed a change to TS 3.5.H.
This change was similar to TS 3.5.H.l.a (described in Section 3.0) requiring the affected system pressure to be restored within one hour in the event of alarm or low discharge pressure.
However, there was no stated course of action to be taken if the line(s) could not be pressurized.
The NRC staff recommended that the licensee revise that proposed change to include such a course of action.
The licensee submitted the changes in a letter dated April 30, 1986.
Our evaluation follows.
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e LPCI and CS Systems The LPCI and CS systems use Residual Heat Removal (RHR)/ core spray fill pump IP-70 as a keep-fill method.
The licensee has stated that the filled status of the CS and LPCI discharge lines are continuously monitored by measuring the static pressure in these lines.
Annunciation woulo cccur on low pressure and thus indicate a low pressure void in the piping.
In the event of low pressure, the proposed TS 3.5.H.1.a would allow one i
hour to restore system pressure.
If the keep-fill condition is not restored (pressurized), then by proposed TS 3.5.H.1.b the affected system would be placed in the test mode and thus pressurized or
. declared inoperable.
We find that operating in the test mode for the CS and LPCI systems is an acceptable approach to maintaining a keep-fill system.
The other alternative, being declared inoperable, would impose existing TS 3.5.A.6, which requires the reactor to be brought to Cold Shutdown within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
This is also acceptable to the NRC staff.
HPIC and RCIC Systems The HPIC and RCIC systems are normally aligned to take suction from the Condensate Storage Tank (CST).
These systems are assumed full by virtue of the CST water level being higher than the discharge piping (to the last block valve).
A backup source for these systems is from the torus.
If these systems are aligned to the torus for some time j
period, voids will exist in the discharge line(s). This presently requires surveillance (TS 4.5.H.1) on a monthly basis by observing water flowing from a high point vent to assure filled pipin0 DAEC has proposed to delete this surveillance.
Instead, when aligned to the torus for suction, proposed TS 3.5.H.1.b would apply. The affected system would be placed in the test mode or be declared inoperable.
As with the LPCI and CS systems, we find that operating in the test mode for the HPCI and RCIC systems is an acceptable method for maintaining a keep-fill system.
This also eliminates the need for the surveillance TS 4.5.H.1.
3.0 TECHNICAL SPECIFICATION CHANGES A summary of IELP's proposed TS changes is presented below.
TS 3.5.H.1.a This TS identifies the action to be taken if the discharge piping of either the CS or LPCI systems is not filled.
In the event of either system alarming on low discharge line pressure, the system pressure is to be restored within one hour or proposed TS 3.5.H.1.b is to be implemented.
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TS 3.5.H.I.b This identifies the action to be taken if the pump discharge lines for the CS, LPCI, HPCI, or RCIC systems are not. filled or TS 3.5.H.1.a(above) is not met.
For any one of these events, the affected system would be placed in the test mode or declared inoperable.
TS 4.5.H and 4.5.H.1 This change modifies the TSs to remove surveillance of the HPCI and RCIC systems related to Maintenance of Filled Discharge Pipe.
I TS 4.5.H.1.a This change modifies the TS (formerly TS 4.5.H.2) to clarify the test
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frequency for the pressure switches which monitor.the LPCI and CS to i
ensure the discharge lines are full.
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q Bases 3.5.H l
This section, entitled " Maintenance of Filled Discharge Pipe" was modified to provide additional information relating to the proposed TS items 3.5.H.1.a and 3.5.H.1.b.
Based upon the review described above, we find the proposed TS changes ll acceptable.
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4.0 ENVIRONMENTAL CONSIDERATION
S This amendment involves a change in the installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20 and a change in surveillance requirements.
We.have determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released of_fsite, and that there is no significant increase in individual or
'I cumulative occupational radiation exposure..The Commission'has previously issued a proposed finding that this amendment involves no significant 1
hazards consideration and there has been no public comment on such I
finding. -Accordingly, this amendment meets 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 this amendment, e
- 5. 0 CONCLUSION We have 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, and j
(2) such activities will be conducted in compliance with the Commission's regulations, and the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
f Principal Contributor:
DKatze Dated: October 29, 1987 1
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