ML020640325
ML020640325 | |
Person / Time | |
---|---|
Site: | LaSalle ![]() |
Issue date: | 02/15/2002 |
From: | Schiavoni M Exelon Generation Co |
To: | Document Control Desk, Office of Nuclear Reactor Regulation |
References | |
IL0048151 | |
Download: ML020640325 (4) | |
Text
S~Exelon.
Exelon Generation Company, LLC www.exeloncorp corn Nmuc LaSalle County Station ear 2601 North 21" Road Marseilles, IL61341-9757 February 15, 2002 United States Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555 LaSalle County Station, Units 1 and 2 Facility Operating License Nos. NPF-1 1 and NPF-1 8 NRC Docket Nos. 50-373 and 50-374
Subject:
Notification of Noncompliance for Exelon Generation Company, LLC LaSalle County Station NPDES Permit No. IL0048151
Reference:
Notice of NPDES Noncompliance letter from M. Schiavoni, Plant Manager - LaSalle County Station, to Illinois Environmental Protection Agency, Division of Water Pollution Control, dated February 15, 2002 In accordance with the 30 day notification requirements of Appendix B, "Environmental Protection Plan," to Facility Operating Licenses NPF-1 1 and NPF-18, Section 5.4.2, "Nonroutine Reports," notification is being provided of a noncompliance with the Exelon Generation Company (EGC), LLC - LaSalle County Station National Pollutant Discharge Elimination System (NPDES) Permit.
On January 16, 2002, an air-operated Unit 2 Circulating Water (CW) Hypochlorite Pump in the Chemical Feed Skid Building was found to be operating outside its timer controlled injection sequence time frame. This resulted in an extended application of Sodium Hypochlorite treatment at the normal feed rate for a period of 13 hours1.50463e-4 days <br />0.00361 hours <br />2.149471e-5 weeks <br />4.9465e-6 months <br />. The NPDES Permit No. IL0048151, Special Condition 13, application limit of two hours per day per main condenser was exceeded on 1/15/02 and 1/16/02.
This event was determined to have negligible potential for endangering health or the environment. Consequently, the event is being reported in accordance with Standard Condition 12(f) of the NPDES permit. The referenced letter provides a Notice of NPDES Noncompliance. A copy of this notice is attached.
Should you have any questions concerning this letter, please contact Mr. William Riffer, Regulatory Assurance Manager, at (815) 415-2800.
Respectfully ar~k ASciavoni *"
Plant Manager LaSalle County Station Attachment cc: Regional Administrator - NRC Region III NRC Senior Resident Inspector - LaSalle County Station
EXELON GENERATION COMPANY, LLC LASALLE COUNTY STATION NPDES PERMIT NO. IL0048151 NONCOMPLIANCE REPORT Outfall Name and Number Not applicable.
Parameter and Permit Limit NPDES Permit No. 1L0048151, Special Condition 13, requires in part that Total Residual Chlorine / Total Residual Oxidant (TRC/TRO) shall not be discharged from any single generating unit's main condensers for more than two hours per day.
Non-Compliance Description, Date and Duration On 1/16/02, an air-operated Unit 2 Circulating Water (CW) Hypochlorite Pump in the vendor owned Chemical Feed Skid Building was found to be operating outside its timer controlled injection sequence time frame. The pump is timed to inject Sodium Hypochlorite for 38 minutes twice per day (0840 - 0918 and 2040 - 2118) into the Unit 2 Main Condenser Circulating Water. Investigation revealed that the pump had started on 1/15/02 at 2040 per the normal timer-controlled sequence, but continued to operate until it was manually secured on 1/16/02 at 0940. This resulted in an extended application of Sodium Hypochlorite treatment at the normal feed rate of approximately 8 liters per minute for a period of 13 hours1.50463e-4 days <br />0.00361 hours <br />2.149471e-5 weeks <br />4.9465e-6 months <br />. The NPDES Permit No. 1L0048151, Special Condition 13, application limit of two hours per day per main condenser was exceeded on 1/15/02 and 1/16/02.
Since the corresponding Unit 2 Circulating Water (CW) Sodium Bromide Pump functioned properly during this period, there was no simultaneous extended application of this chemical. Also, the Unit 1 Chemical Feed System was secured throughout the entire event because the Unit 1 Main Condenser was out of service for a refueling outage. Therefore, applications of treatment chemicals through both main condensers at the same time did not occur during the event.
Cause of Noncompliance The Circulating Water (CW) Hypochlorite Pumps are pneumatically operated diaphragm pumps. Troubleshooting performed by the Chemical Feed vendor revealed that the solenoid valve feeding air to the Unit 2 pump had a foreign substance lodged within its internals. This prevented the de-energized valve from fully closing at the end of the timed sequence, allowing air to be admitted to the pump and causing the continuous operation.
EXELON GENERATION COMPANY, LLC LASALLE COUNTY STATION NPDES PERMIT NO. IL0048151 NONCOMPLIANCE REPORT Plant conditions at the time of the event were as follows:
"* Unit 1 Main Condenser, Circulating Water Pumps, and Chemical Feed were shut down for a refueling outage.
" Only two of three Unit 2 Circulating Water Pumps were running.
" Ice Melt was running, which recirculates 10- 20% of the total Circulating Water flow away from the Main Condenser Discharge Canal to the Lake Screen House Main Condenser Inlet Canal.
These plant conditions resulted in Cooling Lake travel times of 13 - 16.5 days before reaching the lake blowdown. Calculations performed by two independent consultants predicted that Total Residual Chlorine levels from the extended application would dissipate prior to reaching lake blowdown to the Illinois River. A Ph.D. biologist was contacted to determine the impact of the extended application on the fish in the Cooling Lake. He stated that the fish would not be harmed as long as they had areas in the lake to swim away from the application plume. Based on the above considerations, the heath and environmental impacts of this event were considered negligible.
Corrective and Preventative Actions Immediate corrective actions were taken on 1/16/02 to call in the Chemical Feed vendor, who replaced the solenoid valve with a new one. The old solenoid valve was disassembled, and the foreign material deposit lodged in the diaphragm was removed.
The deposit was sent to a lab for analysis and was determined most likely to be Teflon.
The remaining solenoid valves on the skid were disassembled and inspected. No others contained similar deposits. Air lines were inspected and blown clean. Nothing other than a small piece of excess Teflon tape at one of the connections was found.
Chemistry personnel sampled the Cooling Lake to trend Total Free and Residual Chlorine levels as the application plume moved toward the Blowdown Canal. Lake profile samples were collected on 1/17/02, 1/24/02, and 1/28/02 to status the progress of the plume. Inspections of the lake during these sampling periods revealed no evidence of fish kill or distress. To coincide with the predicted arrival of the application plume at the Blowdown Canal, daily samples were collected at the canal on 1/29/02 though 2/1/02. Total Free and Residual Chlorine data were consistent with recent Blowdown sampling results, which supported the calculated predictions. Based on this sampling, Total Residual Chlorine / Total Residual Oxidant (TRC/TRO) at the lake blowdown to the Illinois River never exceeded the 0.05 mg/I permit requirement.
EXELON GENERATION COMPANY, LLC LASALLE COUNTY STATION NPDES PERMIT NO. IL0048151 NONCOMPLIANCE REPORT Preventative actions will be determined from the results of an Apparent Cause Evaluation (ACE) of the equipment failure, which will be completed and approved by station management by 2/22/02.
Name and Number of Facility Contact William Buinickas, Auxiliary Chemist (815) 415-2775 Frederic D. Bevington, Environmental Specialist (815) 415-3243