ML061170621
| ML061170621 | |
| Person / Time | |
|---|---|
| Site: | Indian Point  |
| Issue date: | 03/28/2006 |
| From: | NRC Region 1 |
| To: | |
| References | |
| Download: ML061170621 (12) | |
Text
NRC Special Inspection NRC Special Inspection Indian Point Energy Center Indian Point Energy Center September 20, 2005 September 20, 2005 -- February 28, 2006 February 28, 2006 Contamination of Onsite Groundwater Nuclear Regulatory Commission - Region I Public Meeting, Peekskill, New York March 28, 2006
2 Agenda Agenda
- Overview of Special Inspection
- Discussion of Dose and Dose Limits
- NRC Communications
3 NRC Overview NRC Overview
- Discovery and Initiation of Special Inspection
- Special Inspection Charter and Revision
- Scope of Special Inspection
- Results
- Next Steps
4 Discovery and Initiation of Special Discovery and Initiation of Special Inspection Inspection August 22, 2005 - Moist SFP crack first identified, nothing detectable September 1, 2005 - Contamination detected on swipe sample-NRC informed September 7-15, 2005 - NRC preliminary structural and radiological assessments performed September 12, 2005 - First liquid volume collected for analysis September 19, 2005 - Tritium detected from SFP crack leakage similar to SFP September 20, 2005 - Special Inspection Charter issued October 5, 2005 - Tritium contamination found in an onsite monitoring well (MW-111)
October 7, 2005 - Special Inspection Charter revised
5 Special Inspection Charter and Special Inspection Charter and Revision Revision
- Determine the facts and assess the conditions of the Unit 2 spent fuel pool leak
- Areas of Review: spent fuel pool structural strength, radiological sampling and dose impact assessment, and adequacy of Entergys corrective actions
- Charter was revised to include investigation of groundwater contamination in the Unit 2 transformer yard (MW-111) and monitoring/control of the Unit 1 SFP leakage
6 Scope of Special Inspection Scope of Special Inspection Unit 2 spent fuel pool structural integrity Unit 2 spent fuel pool liner inspection for leaks Radiological assessment of bounding dose calculation Independent sampling of both onsite groundwater and offsite water locations Site groundwater transport characterization Previous samples and data reviewed for possible precursor conditions Unit 1 spent fuel pool leakage collection efficiency
7 Inspection Results Inspection Results No issues relative to Unit 2 spent fuel pool structural integrity Approximately 40% of pool liner inspected - no leaks identified, more to follow Bounding dose calculations continue to indicate that regulatory dose limits are being met The most recent estimated dose was approximately 0.1% of regulatory limits 3-way sample splits between New York State, the NRC, and Entergy confirmed no plant-related activity detected at offsite environmental sampling locations
8 Inspection Results (Cont.)
Inspection Results (Cont.)
Site groundwater characterization efforts are technically sound and provide useful information To date, no circumstances identified that reasonably should have led Entergy to earlier detection or prevention of current onsite conditions Unit 1 spent fuel pool drain system performance and efficiency are not completely understood. Continued efforts are necessary to assure that all leakage is accounted for and effectively handled The cause of the onsite conditions and corrective actions are being pursued in a reasonable manner. Efforts to determine source(s) of contamination and effect mitigation or remediation are progressing.
9 Next Steps Next Steps Continue to assess Entergys performance, effectiveness, and diligence relative to resolving the source and extent of this groundwater contamination Recognizing the evolving nature of this investigation, take appropriate regulatory actions as warranted by inspection findings Continually assess dose consequence, regulatory compliance and impact to public health and safety Evaluate onsite and offsite groundwater monitoring plans to assure early detection of contamination
10 Summary Summary Of Current NRC Assessment Of Current NRC Assessment Based on current information, public health and safety has not been, nor is likely to be, adversely affected.
The source(s) causing ground water contamination have not been positively identified.
The NRC will continue regulatory oversight of Entergys efforts and activities to resolve the condition. A follow-up NRC inspection report will provide final conclusions.
Since discovery, Entergys response has been reasonable and technically sound.
NRC is reviewing generic implications of groundwater contamination.
11 Radiation Dose Perspective Radiation Dose Perspective Background (est.) 360 mrem/year (NCRP 94)
Public Dose Limits 100 mrem/year (10CFR20.1301) 25 mrem/year (40CFR190)
Liquid Effluent Limit 3 mrem/year, total body 10 mrem/year, organ (10CFR50, App. I)
Estimated Dose Rate 0.0034 mrem/year, total body 0.01 mrem/year, bone EPA drinking water limits (40 CFR 141.16)
Tritium (H-3) 20,000 pCi/L Strontium (Sr-90) 8 pCi/L (EPA maximum contaminant level based on 4 mrems per year)
12 NRC Communications NRC Communications
- Lessons learned
- Corrective actions
- Communication efforts going forward