ML20141H911
| ML20141H911 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 11/29/1985 |
| From: | Lacey W DUQUESNE LIGHT CO. |
| To: | Murley T NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| ND1SS1:2617, NUDOCS 8604250239 | |
| Download: ML20141H911 (5) | |
Text
s e
.1bVL
'A@
Telephone (412) 393-6000 Nuclear Group P.o. Box 4 Shippingport, PA 15077-0004 November 29, 1985 NDISS1:2617 Beaver Valley Power Station, Unit No. 1 Docket No. 50-334, License No. DPR-66
)
Special Report Dr. Thomas E. Murley Regional Administrator United States Nuclear Regulatory Commission Region 1 Park Avenue King of Prussia, PA 19406 Gentlemen:
In accordance with Appendix A, Beaver Valley Technical Specifications, 6.9.2, "Special Reports" and 10 CFR 20.405.a.i.v, " Reports of Over-exposures and Excessive Levels and Concentrations", the following Special Report is submitted:
At 1145 hours0.0133 days <br />0.318 hours <br />0.00189 weeks <br />4.356725e-4 months <br /> on October 31, 1985, the Beaver Valley Unit 1 Control Room received notification from an operator at Unit 2 that water was discharging from the open end of an uncompleted Unit 1/ Unit 2 cross-connecting pipe. A Nuclear Control Operator (NCO) immediately began shutting down all unnecessary pumps that were possible supplies for the water. A Radiation Technician was dispatched to begin campling operations. At 1210 hours0.014 days <br />0.336 hours <br />0.002 weeks <br />4.60405e-4 months <br />, the technician notified the Unit 1 Control Room that an initial survey (on a sample taken at the open pipe end) indicated the water was contaminated.
Shortly thereafter, notification s
was received from a Unit 2 Operations Foreman that the water flowing from the pipe had entered a sump in the Condensate Polishing Building. The contents of the sump (1000 gallons) had been discharged to the river between 1135 and 1140 hours0.0132 days <br />0.317 hours <br />0.00188 weeks <br />4.3377e-4 months <br />.
Based on this information, an Unusual Event was declared in accordance with the Station Emergency Preparedness Plan.
The NRC was notified under the provisions of 10 CFR 50.72 (a)(i).
0604250239 851129 PDR ADOCK 0500 4
S 1
P
/
Dr. T. E. Murley Ncvember 25, 1985 NDISS12617 Page 2 Construction personnel were evacuated from the building and security guards were posted to control access to the area. The sump pump was secured. Then Operations and Maintenance personnel were dispatched to isolate the leak and check other possible cross-connect paths. At 1240 hours0.0144 days <br />0.344 hours <br />0.00205 weeks <br />4.7182e-4 months <br />, an NCO noticed that the level in the Boric Acid Hold Tank (BR-TK-7) had decreased. This decrease was the first indication that the tank was the source of the water. The Shift Operating Foreman (NSOF) shut the Boric Acid Hold Tank (BR-TK-7) inlet valve (BR-346) and Hold Tank pump i
suction valves (BR-347) and (BR-348), thus effectively isolating the tank and stopping the leak. At 1255 hours0.0145 days <br />0.349 hours <br />0.00208 weeks <br />4.775275e-4 months <br />, Unit 2 personnel reported the water 5
flow had stopped.
At 1356 hours0.0157 days <br />0.377 hours <br />0.00224 weeks <br />5.15958e-4 months <br />, Unit 2 Operations reported that all possible sump discharge paths were isolated. and at 1550 hours0.0179 days <br />0.431 hours <br />0.00256 weeks <br />5.89775e-4 months <br />, the i
Unusual Event was terminated.
A total of 1600 gallons was determined to have been discharged from BR-TK-7.
All of this amount eventual'ly entered the Unit 2 C6ndensate Polishing sump. After 300 gallons of BR-TK-7 effluent entered the sump j
(already containing 700 gallons of clean water), the 1000 total gallons of water present at that time were pumped into the Ohio River via a storm sewer. The other 1300 gallons of BR-TK-7 effluent that leaked into the sump was subsequently pumped to Unit 1 for appropriate processing.
The spill occurred because the Boric Acid Hold Tank water had flowed out of an open pipe and into the trench where this pipe was located. This trench, running between Unit 1 and Unit 2, is connected to a hallway in the Unit 2 Condensate Polishing Building. The hallway, which acts as a i
continuation of the trench, is adjoined by another corridor that has three floor drains. The water from BR-TK-7 flowed down these two hallways and into the drains, which were discharged into the building sump. The spill had therefore contaminated two hallways of the Condensate Polishing Building, the end of the connecting trench floor drains and the sump.
Two individuals had portions of their clothing contaminated; however, no skin I
contamination occurred.
l Liquid release calculations were performed by the Radiation Control i
Department based on a sample taken from the open ended pipe. These calculations determined the combined concentration of all radionuclides at the point of discharge into the Ohio River. Without taking any dilution factors into account, the calculations indicated that the radionuclide concentration of the discharge when averaged over a period of one hour (excluding tritium) exceeded the Maximum Permissible Concentration (MPC) by a factor of 3.74.
The MPCs used for the calculation were from 10 CFR 20 Appendix B, Table II, Column 2.
As the figure of 3.74 was in excess of I
the limit of 2 MPC as permitted by 10 CFR 50.72 (b)(2)(iv)(B), the NRC was notified at 1730 hours0.02 days <br />0.481 hours <br />0.00286 weeks <br />6.58265e-4 months <br /> within the four-hour requirement of that section.
t,
-.%.,,,.e.-
.,-.e3,
,,,,--e
-v4-
---v-
-.-,.og---c---w.i--r+,.,---,,-.r-,
,r.-,..eu,-,4,vmer.~.-.w---,,.r.mm-
.m-,,m-.
-n,y,.,
t
\\
~
Dr. T. E. Murley November 29, 1985 j
NDISS12617 I
Page 3 i
Final calculations of the liquid release took two dilution factors into consideration. These fsetors include the dilution water in the sump, 4
and the dilution flow rate of the storm sewer.
The total concentration i
including tritium, at the unrestricted area (point of entry to the Ohio i
River) was thus determined to be 37.7 MPC for the five-minute discharge.
I Tritium comprised 28.43 MPC of this total. Therefore, as the MPC of radioactive matcrial released into the unrestricted area exceeded a factor of ten (10), this report is being submitted in accordance with 10 CFR 20.405 (a)(1)(v). However, the effluent concentration (with tritium excluded), when averaged over a period of one hour, was only 0.773 MPC.
Thus, the reporting requirement of 10 CFR 50.73 (a)(viii)(B) does not i
apply. Since the MPCs of 10 CFR 20 Appendix B were exceeded, an apparent j
violation of Technical Specification (TS) 3.11.1.1 had simultaneously 1
occurred, and this report is then also being submitted in accordance with the Action Statement of T.S. 3.11.1.1 and T.S. 6.9.2.
Dose calculations to members of the public were performed for the Limiting Condition of Operation (LCO) 3.11.1.2.
The doses were calculated j
for the maximum individual described in the Station Offsite Dose
{
Calculation Manual. The Total Body Dose for the maximum individual was j
0.469 mrem and the Highest Organ Dose (liver) was 0.677 mrem
'The addition of these doses to the current quarterly and yearly dose totals for the station represents a Total Body Dose of 32.2% of the quarterly Tech. Spec. limit and 32.6% of the yearly Tach. Spec. limit. The Highest Organ Dose represents 14.3% of the quarterly Tech. Spec. limit and 13.8%
j of the yearly Tech. Spec. limit.
i j
This incident was caused by the accidental opening of a Unit 1/ Unit 2 j
cross-connect valve for the Boron Recovery System (BR-79). The valve was inadvertently opened by a construction worker insulating the piping containing it.
This work had been performed in the vicinity of the Boric Acid Hold Tank between 1035 and 1100 hours0.0127 days <br />0.306 hours <br />0.00182 weeks <br />4.1855e-4 months <br /> on October 31, 1985. The
)
valve, a 1 1/2 inch ball valve, had been danger tagged as part of an Operations clearance and a Construction clearance in 1977. However, the j
tags had deteriorated over the years and were not present at the time of the incident. The valve was the only means of isolating the uncompleted 4
cross-connect line, which was uncapped. When (BR-79) was opened, water flowed through the Boric Acid Hold Tank pump suction valves then through a series of valves aligned for BR-TK-7 recirculation, past (BR-79) and out the pipe. To prevent a future recurrence of this problem, (BR-79) has i
1 been locked in a closed position while a cap was welded to the end of the j
line on November 25, 1985. Another Boron Recovery System cross-connect line with a locked isolation valve also had a cap installed at this time.
j l
Five other lines in the same area that could possibly contain radioactive 1
i j
f 1.
Dr. T. E. Murley l
November 29, 1985 NDISS12617
)
Page 4
\\
effluent had been previously capped.
In addition, a barrier was installed j
at the end of the trench containing these lines. Furthermore, the j
clearance was reposted, and plastic laminated danger tags were affixed to i
the cross-connect valves specifying that they be kept closed. Therefore, j
it is now believed that all Unit 1/ Unit 2 cross-connect lines that could ij possibly transport radioactive fluids have been provided with some sort of l
double isolation boundary.,
1 l
The safety implications to the public and plant were minimal. All i
individuals in the area were frisked by Radiation Technicians, and no skin j
contaminations were detected. Furthermore, samples were taken at the j
Midland water treatment facility, and no isotopic concentrations greatar then the lower limit of detectability for the spectrometer were detected.
Very truly yours, 1
b yA Wm. S. Lacey Plant Manager i
l
{
GVC/ vat
)
4 1
I i
1 1
I l
i 4
I i
b b
1 1
ia-
~
Dr. T. E. Murley November 29, 1985 NDISS1:2617 Page 5 cc: Director of Management & Program Analysis United States Nuclear Regulatory Commission Washington, DC 20555 C. A. Roteck, Ohio Edison Director, Office of Inspection and Enforcement Headquarters United States Nuclear Regulatory Commission Washington, DC 20555 Mr. Peter Tam, BVPS Licensing Prcject Manager United States Nuclear Regulatory Commission Washington, DC 20555 W. Troskoski, Nuclear Regulatory Commision, BVPS Site Inspector Mr. Alex Timme, CAPCO Nuclear Projects Coordinator, Toledo Edison INPO Records Center Suite 1500 1100 Circle 75 Parkway Atlanta, GA 30339 G. E. Muckle, Factory Mutual Engineering, Pittsburgh Mr. J. A. Triggiani, Operating Plant Projects Manager i
Mid Atlantic Area Westinghouse Electric Corporation Nuclear Services Integration Division Box 2728 Pittsburgh, PA 15230 American Nuclear Insurers c/o Dottie Sherman, ANI Library The Exchange Suite 245 270 Farmington Avenue Farmington, CT 06032
__