ML12130A152
ML12130A152 | |
Person / Time | |
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Site: | Limerick ![]() |
Issue date: | 05/09/2012 |
From: | Cuthbert D Alliance For A Clean Environment |
To: | Division Reactor Projects I |
krohn, pg | |
References | |
Download: ML12130A152 (5) | |
Text
Response to Issues Discussed Between the NRC Staff And the Alliance for a Clean Environment (ACE)
At the Limerick Annual Assessment Meeting on April 18, 2012 Extended Power Uprates An issue was discussed regarding the safety of a 20% power uprate from a generic standpoint.
The generic approach to justify up to a 20% power uprate for boiling-water reactors is discussed in General Electric (GE) Licensing Topical Report NEDO-33004-A dated July 2003. The GE report and the NRCs safety evaluation approving the use of this report are publicly available on the NRCs website at the following weblink:
http://pbadupws.nrc.gov/docs/ML0321/ML032170332.pdf Limerick Spent Fuel Pool Concrete An issue was discussed regarding the structural adequacy of the concrete for one of the spent fuel pools at Limerick based on statements made by a quality assurance engineer at a Limerick license renewal public meeting held on September 22, 2011. A transcript of the meeting is publicly available on the NRCs website at the following weblink:
http://pbadupws.nrc.gov/docs/ML1127/ML11272A237.pdf The specific issue in question is discussed on page 155 of 199 of the pdf file in the weblink above (discussion by Mr. Dan Ely). Following the meeting, the NRC staff looked into this issue and substantiated that there were deviations in a concrete pour for the spent fuel pool as stated by Mr. Ely. However, the NRC staff also found that this specific issue had been determined (at the time of plant construction) to have no adverse effect on the structurally adequacy of the spent fuel pool.
Earthquake Fault Near Limerick Site A concern was raised regarding whether the NRC was aware of the Sanatoga fault and its proximity to the Limerick site. NUREG-0991, dated August 1983, is the NRCs Safety Evaluation Report (SER) concerning the application for an operating license for Limerick, Units 1 and 2. As discussed on page 2-44 of the SER, the NRC noted that three faults have been mapped and investigated within 2 miles of the site. The closest one is the Sanatoga fault.
A panel of experts in Appalachian geology and the NRC staff concluded that that these faults have experienced their last displacements more than 500,000 years ago. This section of the SER concluded that there were no capable faults in the site area.
Station Blackout Rule During discussion regarding station blackout (SBO), the NRC staff mentioned that there were plans to revise the SBO rule. A question was raised regarding opportunity for public comments.
The following NRC news release provides the details regarding public comment:
http://pbadupws.nrc.gov/docs/ML1208/ML120800453.pdf Spent Fuel Pool Level Instrumentation
A question was raised regarding the timeframe for licensee implementation of spent fuel pool level instrumentation based on one of the recent Orders the NRC issued in response to the events at Fukushima Dai-ichi. The specific implementation timeframes are discussed in Section IV of NRC Order EA-12-051, dated March 12, 2012. The Order is publicly available on the NRCs website at the following weblink:
http://pbadupws.nrc.gov/docs/ML1205/ML12054A679.pdf Decommissioning Funding Assurance A number of questions were asked regarding decommissioning funding assurance for Limerick.
The questions referenced Exelons letter dated February 23, 2011 (ADAMS Accession No. ML12054A256). This letter provided information to the NRC staff regarding decommissioning funding assurance for Limerick Unit 1. The NRC staff is currently reviewing this submittal and, in a letter dated April 20, 2012 (ADAMS Accession No. ML121080344), the NRC staff requested that Exelon provide additional information. As this review is ongoing, it would be inappropriate to address questions pertaining to this review. However, the information below is provided to address this issue generically.
The NRC conducts an independent analysis of licensee reports, required to be filed pursuant to 10 CFR 50.75(f)(1), on the status of decommissioning funding assurance for each operating nuclear power reactor or part of a reactor that licensees own. These reports, which were initially submitted by March 31, 1999, and are to be submitted at least once every two years thereafter by March 31, reflect funding assurance data as of the end of the preceding calendar year (the reporting year). The NRC staff performs an independent analysis of each of these reports for operating plants to determine whether licensees have provided reasonable assurance that sufficient funding for radiological decommissioning of the reactor will be available at the time permanent termination of operation (license expiration date) is expected. Further information regarding decommissioning funding assurance can be found on the NRCs website at the following weblink:
http://www.nrc.gov/about-nrc/regulatory/decommissioning/finan-assur.html Clean-up Costs A number of questions were asked regarding clean-up costs in the event of an accident at Limerick. Details regarding nuclear insurance and disaster relief funds can be found on the NRCs website at the following weblink:
http://www.nrc.gov/reading-rm/doc-collections/fact-sheets/funds-fs.pdf GE Part 21 Notification MFN-10-243, Channel-Control Blade Interference What is the cost of a control rod blade and/or channel replacement to eliminate the friction problem?
Control rod friction issues are actually caused by bowing of fuel channels surrounding the fuel rods, not the control rods. Replacing the fuel channel will correct the issue. The cost of replacing a fuel channel is considered Exelon proprietary information.
Were the control rods that showed high friction during testing in December 2011 replaced during the recent Unit 1 outage?
The fuel assemblies loaded around the control controls that showed high friction were removed from the reactor during the refueling outage and stored in the spent fuel pool.
Was recent testing performed on Unit 2?
The last performance of control rod friction testing performed on Unit 2 was on December 19, 2010. Of the 36 control rods tested due to potential susceptibility to channel bowing none exhibited increased friction. Testing of control rods is currently planned to be performed in an upcoming maintenance outage later this Spring.
Quantity of Used Fuel Assemblies at Limerick The exact amounts of special nuclear material in a licensees possession is considered to be security sensitive information and not permitted to be released to the public.
Readily Available Water Sources at Limerick Units 1 and 2 cooling tower volumes - Per the Limerick Updated Final Safety Analysis Report (UFSAR), each cooling tower contains 7.2 million gallons of water. With the fire system pumping capacity of 5000 gpm using both fire pumps, this allows a continuous supply of water for 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br />.
Spray pond volume - Per Table 9.2-0 of the UFSAR, the Spray Pond has a normal operating level equivalent to 29.06 million gallons. The area of the Spray Pond is 9.6 acres.
Additional sources of water could be used to fight fires and accidents - A backup diesel-driven fire pump takes suction from the Backup Fire Water Storage Tank. The tank is maintained at a level corresponding to 311,000 gallons. This tank is filled from a ground water well with the Batch Well Pump.
Abnormal Radioactive Waste Discharge on March 19, 2012 Timeline of events 3/19 0135 - Floor Drain Sample Tank #2 (treated radioactive waste) discharge initiate.
3/19 0250 - Abnormal release through Outfall 023 was observed. The Control Room was contacted and the release was secured.
3/19 0400 - Sample of water was collected in the immediate vicinity of Outfall 023.
3/19~1200 - Analysis of sample results were completed. Samples in the immediate vicinity of Outfall 023 indicated elevated levels of tritium.
3/19 1700 - Exelon initiates a prompt investigation into the issue and implements additional controls to prevent overflow of cooling tower blowdown through Outfall 023.
NRC resident inspectors are informed of the prompt investigation.
3/20 - NRC dispatches a radiation protection specialist to Limerick to assist the resident inspectors in the review of the event and the actions taken by Exelon.
3/20 ~1700 - State and local officials were informed of increased levels of tritium from water samples that were collected from impacted areas.
3/21 - Schuylkill River diffuser, the cause of the backup of cooling tower blowdown water due to clogging, was cleaned.
4/11 - Exelon makes a 10CFR50.72 event notification (EN 47823) to the NRC regarding the abnormal radioactive release through Outfall 023 and the notification of the event to state and local officials.
5/7- NRC issues a Severity Level IV Non Cited Violation in NRC Inspection Report 05000352 & 05000353/2012002 (ML12128A373), for failure to make a timely 10CFR50.72 notification.
The water companies are provided in the Limerick Generating Station Units 1 and 2 Annual Radiological Environmental Operating Report:
- Philadelphia Suburban Water - (sample location 15F4)
- Phoenixville Water Works - (sample location 15F7)
- Citizens Home water Company - (sample Location 16C2)
Exelon communicated with the Governors office and various congressional offices, as well as other state and local representatives regarding the inadvertent release and its potential environmental impacts.
Radionuclide/isotopes test results of spill water Exelon conducted an analysis for tritium as well as for potential gamma emitters such as Cobalt 60 and Manganese 54. Although tritium was detected in the spill water, no gamma emitters were detected.
Test results from water company samples These sample results for water company samples were generally at or near minimum detectable activities. These minimum detectable concentrations were generally at or below approximately 200 pCi/l (i.e., less than approximately 1% of the EPA drinking water standard). These results covered the period of the spill as well as the time period following the spill.
Documents Requested NRC 2012 first quarter inspection report containing the discussion of the March 19 abnormal discharge. ML12128A373 Issued May 7, 2012 Inspection report discussing the Unit 2 Preliminary White Finding associated with the Unit 2 Reactor Core Isolation Cooling System http://adamswebsearch2.nrc.gov/webSearch2/main.jsp?AccessionNumber='ML11308B146' Inspection report for Unit 2 Reactor Core Isolation Cooling System Final White Finding and Notice of Violation http://adamswebsearch2.nrc.gov/webSearch2/main.jsp?AccessionNumber='ML113410132'
Copy of 2011 Annual Radioactive Effluent Release Report See attached PDF Copy of 2011 Annual Radiological Environmental Operating Report See attached PDF