05000456/FIN-2013003-04
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Finding | |
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| Title | Implementation of Lake Chemistry Management Program |
| Description | The inspectors identified an URI associated with the licensees implementation of station procedural standards to notify Senior Site Management and Operations at the first sign of a lake softening event, and to implement AOP BwOA-ENV-7, Adverse Cooling Lake Conditions, when pre-determined calcium precipitation rate limits were exceeded on three occasions from March 2012 through April 2013. The licensees root cause analysis performed following a 2004 Braidwood Lake Precipitation Event (IR 199206, Lake Chemistry Trend Calcium Carbonate Issue, Assignment 13) identified that the Lake Chemistry Plan had not been formalized into operational procedures and, as a result, guidelines for administrative controls, actions limits and levels, and contingency actions had not been established for managing lake chemistry. As one of the corrective actions to address this issue, the licensee developed and implemented AOP BwOA-ENV-7, Adverse Cooling Lake Conditions, to address any future adverse lake precipitation event (IR 199206, Assignment #35). On November 10, 2004, BwOA-ENV-7, Adverse Cooling Lake Conditions, was approved, placed within the station procedures, and was required to be followed in accordance with station standards. This AOP stated that prompt actions may be required to minimize any adverse effects on plant operation. Procedure BwOA-ENV-7 required that several actions be performed to minimize the impact of a significant lake precipitation event. For example, the procedure directed numerous actions to determine whether there had been an adverse impact on plant systems. These actions included the observation of traveling screen operation, monitoring of safety-related and nonsafety-related service water system strainer performance, trending of main condenser pressure, and the monitoring of component cooling system heat exchanger performance, fire protection jockey pump performance, and reactor containment fan cooler service water flow. Upon the identification of any adverse impact, the procedure directed notification of the Braidwood Station Duty Team to ensure appropriate actions would be taken commensurate with safety. Additionally, immediately following entry, BwOA-ENV-7 required that the Emergency Director evaluate Emergency Plan conditions. The procedure also required that the licensee minimize SX and auxiliary feedwater pump, main control room chiller, and EDG operation to preclude chemical or biological fouling. Following issuance, BwOA-ENV-7 had been revised numerous times to modify the thresholds and standards for informing Senior Site Management and Operations of lake precipitation events and to specify the standards upon which Operations would be notified to implement the procedure. For the period of January 2012 through May 2013, CY-BR-120-412, Lake Chemistry Data Sheet, Revision 7 was in effect and required the following: At the first sign of a precipitation event or natural softening, NOTIFY Senior Site Management and Operations (Reference Section 3.5). COMPARE Calcium Hardness and Total Alkalinity trends to determine behavior of these parameters during period of softening and non-softening. (Reference Section 4.6.5) - REVIEW CW Makeup and blowdown flow history, as well as recent weather precipitation. - If lake softening rate exceeds 15 ppm [parts per million] Calcium Hardness in a 2-3 day period, NOTIFY Operations to enter BwOA-ENV-7. The inspectors reviewed Braidwood Lake chemistry data from January 2012 through April 2013. The inspectors identified that the licensee appeared to have not followed the standards discussed above for three of the five potential lake softening events during this period. Specifically, the inspectors identified that Senior Site Management and Operations notification and entry into procedure BwOA-ENV-7, Adverse Cooling Lake Conditions, was delayed for up to several days after the licensee had performed lake water sampling, had analyzed the sample, and had documented the results. The following specific examples were identified: 2012 First Lake Softening Event (BwOA-ENV-7 Entered on March 5, 2012 3 Days After Entry Conditions were Present Date Calcium Delta Between Prior Day Sample 2/29/2012 257 3/2/2012 231 (26) - 2012 Third Lake Softening Event (BwOA-ENV-7 Entered on April 15, 2012 2 Days After Entry Conditions were Present) Date Calcium Delta Between Prior Day Sample 4/11/2012 194 4/13/2012 167 (27) - 2013 Second Lake Softening Event (BwOA-ENV-7 Entered on April 4, 2012 1 Day After Entry Conditions were Present) Date Calcium Delta Between Prior Day Sample 4/1/2013 209 4/3/2013 191 (18) The inspectors determined through interviews with licensee personnel and through the review of Operations logs that the licensee had not notified Senior Management and Operations at the first signs of the listed lake softening events or had implemented BwOA-ENV-7 earlier than was documented in the Operations logs. As a result of not implementing BwOA-ENV-7, Adverse Cooling Lake Conditions, when required, the licensee did not appear to perform the actions required by the AOP in a time frame commensurate with station standards. Therefore, the licensee failed to meet the standards that they had originally developed and modified over the years to minimize the possible adverse effects of lake precipitation events. The inspectors discussed this issue of concern with licensee staff, management, and senior management who disagreed with the inspectors assessment. The main points of the disagreement were on the meaning of the term at the first sign and on the acceptability of allowing a sample to be taken and analyzed on one day but not reviewed by a supervisor through the Lake Chemistry Control Program until chemistry staff were available, potentially several days later. The inspectors inferred from the term at the first sign that actions were required to be performed without an undue delay and that these actions were not dependent upon readily available chemistry staff. In the past two lake precipitation events, plant equipment was adversely impacted relatively soon after the onset of the event. The inspectors recognized that the elevated differential calcium concentration samples identified during this inspection did not actually result in a lake precipitation event. As of the end of the inspection period, the licensee planned to determine the impact of a 2-3 day delay in implementing BwOA-ENV-7 on the ability to mitigate a lake softening event. Pending a review of this information, this issue is considered a URI. (URI 05000456/2013003-04; 05000457/2013003-04, Implementation of Lake Chemistry Management Program) |
| Site: | Braidwood  |
|---|---|
| Report | IR 05000456/2013003 Section 4OA2 |
| Date counted | Jun 30, 2013 (2013Q2) |
| Type: | URI: |
| cornerstone | Mitigating Systems |
| Identified by: | NRC identified |
| Inspection Procedure: | IP 71152 |
| Inspectors (proximate) | M Bielby M Holmberg M Perry R Baker R Ng T Go V Meghani A Garmoe E Duncan J Benjamin J Robbins J Steffesm Learnm Perry N Feliz Adorno R Edwards R Ng T Daun T Go V Meghani A Dahbur A Dunlop A Garmoe A Sallman E Duncan J Benjamin J Neurauter J Robbins |
| INPO aspect | |
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Finding - Braidwood - IR 05000456/2013003 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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Finding List (Braidwood) @ 2013Q2
Self-Identified List (Braidwood)
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