ML20217A321
| ML20217A321 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 03/17/1998 |
| From: | NORTHEAST NUCLEAR ENERGY CO. |
| To: | |
| Shared Package | |
| ML20217A314 | List: |
| References | |
| NUDOCS 9803240362 | |
| Download: ML20217A321 (5) | |
Text
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Docket No. 50-d2}
Bf/127 Millstone Nuclear Power Station, Unit No. 3 Marked Up Technical Spocification Page l
l I
March 1998 9903240362 900317 PDR ADOCK 05000423 P
PDR y
l EMERGENCY CORE COOLING SYSTEMS 2/12/90 BASES l
ECCS SUBSYSTEMS (Continued)
The Surveillance Requirements provided to ensure OPERABILITY of each component ensures t%t at a minimum, the assumptions used in the safety analyses are met and that subsystem OPERABILITY is maintained. Surveillance Requirements for throttle valve position stops and flow balance testing provide assurance that proper ECCS flows will be maintained in the event of a LOCA. Maintenance of proper flow resistance and pressure drop in the piping system to each injection point is necessary to:
(1) prevent total pump flow from exceeding runout conditions when the system is in its minimum resistance configuration, (2) provide the proper flow split between injection points in accordance with the assumptions used in the ECCS-LOCA analyses, and (3) provide an acceptable level of total ECCS flow to all injection points equal to or above that assumed in the ECCS-LOCA analyses.
Surveillance Requirement 4.5.2.b.1 requires verifying that the ECCS piping is full of water exceat for the operating centrifugal charging pump (s) and associated piping, and tie RSS pump, the RSS heat exchanger and associated RSS piping. The ECCS pumps are normally in a standby, nonoperating mode, with the exception of the o)erating centrifugal charging pump (s). As such, the, f
ECCS flow path piping has tie potential to develop voids and pockets of
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entrained gases. Maintaining the piping from the ECCS pumps to the RCS full of
. water ensures that the system will perform properly when required to inject into the RCS. This Surveillance Requirement is met by venting ECCS pump casings and the accessible discharge piping high points except for:
(1) the RSS pump, RSS heat exchanger and associated RSS piping that is not maintained filled with water during plant operation is excluded from the Surveillance Requirement, (2) the operating centrifugal charging pump (s) and associated piping is also excluded as an operating pump is self venting and cannot develop voids and pockets of entrained gases, and (3) the nonoperating centrifugal charging pumps do not have casing vent connections and the pump manufacturer indicates that venting the suction pipe will assure that the pump casing does not contain voids and pockets of entrained gases. The venting of the nonoperating centrifugal charging pumps l
is accomplished by venting with the suction line test connection.Qn mr]
Surveillance Requirement 4.5.2.C.2 requires t!at the visual inspection of the containment be performed at least once daily if the containment has been entered that day and when the final containment entry is made. This will reduce the number of unnecessary inspections and also reduce personnel exposure.
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HILLSTONE - UNIT 3 B 3/4 5-2 Amendment No. Jpp, J R,.157 0607
INSERT:
This surveillance requirement is met using an external water level detection method (as opposed to venting) for the water filled portions of RSS piping upstream of valves 3RSS*MV8837A/B and 3RSS*MV8838A/B, since venting would breach containment pressure boundary.
Enter LCO action statement 3.6.2.2 if venting is deemed necessary.
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Docket No 50-423 B17127 Millstone Nuclear Power Station, Unit No. 3 Retyped Technical Specification Page March 1998
'ENERRENCY C0RE COOLING SYSTEMS BASES ECCS SUBSYSTEMS (Continued)
)
l The Surveillance Requirements provided to ensure OPERABILITY of each component ensures that at a minimum, the assumptions used in the safety analyses are met and that subsystem OPERABILITY is maintained.
Surveillance Requirements for throttle valve position stops and flow balance testing provide assurance that proper ECCS flows will be maintained in the event of a LOCA. Maintenance of proper flow resistance and pressure drop in the piping system to each injection point is necessary to:
(1) prevent total pump flow from exceeding runout conditions when the system is in its minimum resistance configuration, (2) provide the proper flow split between injection points in accordance with the assumptions used in the ECCS-LOCA analyses, and (3) provide an acceptable level of total ECCS flow to all injection points equal to or above that assumed in the ECCS-LOCA analyses.
Surveillance Requirement 4.5.2.b.1 requires verifying that the ECCS piping is full of water except for the operating centrifugal charging pump (s) and associated piping, and the RSS pump, the RSS heat exchanger and associated RSS piping. The ECCS pumps are normally in a standby, nonoperating mode, with the exception of the o>erating centrifugal charging pump (s). As such, the ECCS flow path piping has tte potential to davelop voids and pockets of entrained gases. Maintaining the piping from the ECCS pumps to the RCS full of water ensures that the system will perform properly when required to inject into the RCS. This Surveillance Requirement h act by venting ECCS pump casings and the accessible discharge piping high points except for:
(1) the RSS pump, RSS heat exchanger and associated RSS piping that is not maintained filled with water during plant operation is excluded from the Surveillance Requirement, (2) the operating centrifugal charging pump (s) and associated piping is also excluded as an operating pump is self venting and cannot develop voids and pockets of entrained gases, and (3) the nonoperating centrifugal charging pumps do not have casing vent connections and the pump manufacturer indicates that venting the suction pipe will assure that the pump casing does not contain voids and pockets of entrained gases. The venting of the nonoperating centrifugal charging pumps is accomplished by venting with the suction line test connection. This surveillance requirement is met using an external water level detection method (as opposed to venting) for the water filled portions of RSS piping upstream of valves 3RSS*MV8837A/B and 3RSS*MV8838A/B, since venting would breach containment pressure boundary. Enter LC0 action statement 3.6.2.2 if venting is deemed necessary.
Surveillance Requirement 4.5.2.C.2 requires that the visual inspection of the containment be performed at least once daily if the containment has been entered that day and when the final containment entry is made. This will reduce the number of unnecessary inspections and also reduce personnel exposure.
NILLSTONE - UNIT 3 8 3/4 5-2 Amendment No. #p. #7, #7.
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