ML051460223
| ML051460223 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 05/20/2005 |
| From: | - No Known Affiliation |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| FOIA/PA-2005-0207 | |
| Download: ML051460223 (4) | |
Text
0829 Mill-3 Rx Trip and SI on the 'A' train because of low steam pressure on UB" steam line. MSIVs closed. Several main steam safety valves lifted. Some may have lifted at a lower pressure that designed. Primary safety lifted and then reseated.
Entered E-0.
0842 Millstone 3 declared an Alert C1due to main steam safety relief valve lift on HUB" steam generator (20 Main steam safety valves total at Millstone-3). Reactor trip occurred. SI occurred.
0953 NRC entered Monitoring Mode NRC Requested ERDS to be initiated - Dominion having some difficulty in establishing ERDS 1005 First responder arrived in Region I IRC 1010 NRC Requested ERDS to be initiated - Dominion having some difficulty in establishing ERDS 1040 NYS contacts NRC Ops Center to request event briefing.
1045 R. Bores contacted RI IRC. CT notified and NYS (A. Feeney) will be notified.
1054 Status update - AFW terry turbine started and then tripped and then manually restarted. Currently feeding with three aux feed pumps.
1058 SRI in the Millstone control room. MSIV's are closed, ADVs are being used for pressure, three AFW pumps in service 1105 Status update from Dominion - Cause for trip is not determined. Dominion has considered tampering and has no reason to believe that tampering is an issue.
After SI pressurizer went solid. Met SI termination criteria. Established normal charging currently pressurizer level 64% and pressurizer pressure 2002 psig.
Dominion has send some individuals to the armory but state personnel are not present. Dominion has some personnel in its corporate EOF. Radiation levels are normal. No evidence of a primary/secondary leak. Dominion is developing criteria for terminating from the Alert. An increase of level in the PRT indicates evidence of some primary system leakage.
1113 ERDS has not yet been established 1130 W. Lanning requested SRI to provide briefing on the event.
fl; 1
1132 W. Lanning / Max Schnieder updating Ellis - PRL - 64% PRT Level - 82%
increasing slowly RX pressure - 2000psig. Dominion developing termination criteria. No evidence of tampering but still being pursued. ADVs controlling pressure. During the week, Dominion replaced a power supply on pressure instruments for the UB" steam line. Low steam pressure on one steam line caused Rx trip and SI. MSIV's closed. ADV being manually controlled. No indication of Pri/Sec leakage and no fuel leakage. TDAFW pump tripped when started but was successfully restarted. Charging system has a packing leak that has been isolated. PRT level is slowly increasing provide evidence of some primary system leakage from either the Pressurizer safety or PORV.
1155 W. Lanning asked M. Kevin Mangan also on site. Discussed consideration adjusting outage work on Millstone 2 since Millstone 3 is in an Alert.
1200 ERDS is functioning 1222 No problems with electrical alignment 1225 Dominions status update - Plant 88 'F subcooled. Pressurizer level - 57%,
cooling down the PRT using primary grade water (draining the PRT and replacing it with primary grade water). 1080 Steam Pressure. AFW feeding SGs to maintain level. Rad levels did not change or have not changed during the event. A,B, & C SGs sampled no pri/sec leak, D sample is in progress. PRT is being cooled. Tail pipe temperatures on PORV and Safeties 220 F and stable. Dominion asked interpretation of tail pump data. They believe that leakage is from the pressurizer safety not PORV. Both PORV block valves are open. ES 1.1 still in effect. Still in Alert. Dominion is beginning a shift brief on entering procedure to cooldown the primary system. Dominion has notified state and local officials. Dominion has issued a press release at 11:17.
1240 Discussion with Dominion Emergency Director - Plan is to go to cold shutdown.
They will exit ES 1.1 and transition to normal plant procedures. No rad releases and radiation levels have been stable. They expect to terminate from the Alert later this afternoon. They are working through their termination procedure. Little if any press interest at this time. As part of SI, chilled water to containment isolated. As a result of lossof cooling to containment, containment pressure slowly increased. Dominion has restored chilled water to containment and are slowly reducing containment pressure.
1253 Report from Bores - State CT and NY EOCs are staffed 1306 TA Briefing Conducted -
1331 Report from SRI - both Rls and one NSPDP intern on site. Plant cooldown limited because of the flowrate capacity of the bypass valves around the ADVs.
1352 Report from Bores - CT towns have staffed their EOC's. Towns are beginning to stand down their town EOCs.
Page 2
1406 Status update from Dominion - In the normal procedures and will shortly begin cooldown. Still determining criteria for termination of Alert. Si was reset at about 0900, but there is still a signal causing MSIV closure and cannot be reset.
Dominion is investigating why there is still a signal present. Millstone 3 is in Mode 3 - Hot Standby and believes that they will have to get to Mode 4 (<350 OF) by 2029. Dominion expects to be less than 350*F at 1730 hours0.02 days <br />0.481 hours <br />0.00286 weeks <br />6.58265e-4 months <br />. If they cannot achieve <350 0F) by 2029 Still do not have the results for the "D" SG sample but do not believe that there is any pri/sec leakage. Dominion will provide an estimate of the time the sample results will be available. I 1458 P. Krone discussion with NRR Tech Staff Branch regarding interpretation of TS 3.7.1.1 regarding the time allowed to get to cold shutdown.
1515 W. Lanning Briefed IRC. Dominion has stopped cooldown using the D SG because of the sample data regarding pri/sec leakage is not yet available.
Dominion has switched to using the A SG for plant cooldown.
1520 Dominion status briefing - Secured C and D RCPs to support a cooldown rate of about 60 0F per hour Reevaluate termination criteria at 1600 hours0.0185 days <br />0.444 hours <br />0.00265 weeks <br />6.088e-4 months <br />. "D" SG Normal sample point cannot be used as a result a backup sample is being obtained off of the SG blowdown line. No time provided for completion of the sample. SG A, B, & D are supplying steam to the TDAFW pump. Area Rad levels on the steam supply line to the TDAFW pump do not show any pri to sec leakage. No information yet on initiating event. Some news media interest (CBS) and local newspapers. Are in the process of issuing a second press release.
Dominion has rad monitor teams out getting samples on site and off- site and have not seen anything other than background.
1530 Dominion issued a second press release 1600 W Lanning brief of T. Reis - on available radiation information on the D SG level.
No increase in RCS activity. About 3 gpm leak from PORV into the PRT. No media interest directed to the Region.
1624 Update from Schneider - Leakage from the 'A" charging valve packing was confirmed to be about 1000 gallons.
1634 Update from Silas - TSC priorities are establish SG blowdown to get SG A and D samples and to determine which PORV is leaking 1638 Update from Doerflein - Dominion has determined that the 'A" PORV was leaking 1640 Update from Dominion - Cooldown initially going a little slower than expected, now picked up > 60 deg F per hour. The TDAFW has been secured. Will shortly reassess Alert termination. Termination criteria: clear the initiating event - which has occurred and have confidence that they will meet TS 3.7.1.1. Will get back to Region at about 1730. Cooldown is the priority, second priority is obtaining sample on "D" SG.
1708 Update from Schneider - Expect SG sample data in two hours. Dominion has not reset main steam isolation to preserve evidence for troubleshooting.
Page 3
1720 Update from Schneider - There is not sufficient evidence that the "A" PORV was the PORV leaking., Dominion is still investigating..
1724 Update from Dominion - Based on progress with cooldown will terminate from Alert at 1730. Expect 90 minutes to Mode 4. The A PORV is isolated but that does not appear to be leaking PORV. Will continue with its investigation of the source of leakage into the PRT. When the cooldown was begun, Dominion was able to block the low steam pressure signal, however Dominion has not reset main steam isolation to preserve evidence for troubleshooting.
1738 Update from Schneider - cooldown rate about 60 deg F per hour 1800 Update from Dominion - Will stay in Alert until they achieve Mode 4. Placing "D" generator on blowdown to get a sample.
1826 Update from Silas - Dominion completed tampering procedure at 1305 with no evidence of tampering found 1842 Update from Schneider - B PORV isolated and the downstream temp decreased.
Dominion concluded that B PORV was the leaking valve. Estimated that D SG sample in about 90 minutes.
1900 Update from Dominion - 353 0F RCS temp, Will teminate Alert in about 3 minutes.
1903 Update from Schnieder - Dominion announced that they have achieved Mode 4 and have terminated the Alert 1912 Decision made by RI IRC that currently there is no reason to have the resident inspector report to site at 0100 on 4/18. The resident inspector should report for normal duty in the morning. Dominion is de-staffing the TSC. Resident in TSC is also leaving the site.
1945 Habighorst on site - Schneider has left site.
2000 RI will remain in Monitoring Mode until licensee is on RHR shutdown cooling and
'D' steam generator sample is acquired. RI IRC will be a minimum staff of 2 until that criteria is met. Resident inspector will continue to monitor at the site.
2028 W. Lanning briefed Meschoff, Dyer, Collins, McGuinty on the termination of the Alert and the criteria established for securing from the Monitoring Mode.
Agreement was reached on the criteria: Plant is on RHR shutdown cooling and 'D' steam generator sample is acquired.
Page 4