ML23271A061

NPS, Units 1 and 2, Reference for ISFSI from Zion Solutions

ML23271A061
Person / Time
Site:	Zion  File:ZionSolutions icon.png
Issue date:	09/26/2023
From:	Wheat J Energy Solutions
To:	Amy Snyder Reactor Decommissioning Branch
References
Download: ML23271A061 (1)

Text

From: Justin T. Wheat To: Amy Snyder Cc: Amy C. Hazelhoff

Subject:

[External_Sender] Zion Dose Evaluation Information Date: Tuesday, September 26, 2023 10:53:38 AM Attachments: image001.png

Amy, I was able to locate the information we discussed during the recent Zion project status call.

The current version of the Zion Nuclear Power Station 10 CFR 72.212 Evaluation Report is Revision 10, which states:

A total of 1128 hours0.0131 days <br />0.313 hours <br />0.00187 weeks <br />4.29204e-4 months <br /> were spent on average on an annual basis by ComEd workers in the switchyard over the last 3 years. The maximum number of hours a worker spent in the switchyard was 445 hours0.00515 days <br />0.124 hours <br />7.357804e-4 weeks <br />1.693225e-4 months <br /> annually. Conservatively, it is assumed a ComEd project requires a worker to spend 2088 hours0.0242 days <br />0.58 hours <br />0.00345 weeks <br />7.94484e-4 months <br /> a year in the switchyard (Reference 24.152). This would represent the worst case bounding occupancy that could reasonably be anticipated for a major rebuild or repair in the south end of the Switchyard. The 2,088 hour0.00102 days <br />0.0244 hours <br />1.455026e-4 weeks <br />3.3484e-5 months <br /> bounding occupancy far exceeds the worst case estimate of 445 hours0.00515 days <br />0.124 hours <br />7.357804e-4 weeks <br />1.693225e-4 months <br /> provided by ComEd as an input in Reference 24.152. Using the bounding occupancy of 2,088 hours0.00102 days <br />0.0244 hours <br />1.455026e-4 weeks <br />3.3484e-5 months <br /> a year, the anticipated annual dose for work in the 345 kV Switchyard would be 37.6 mrem per year. This is within the 10 CFR 20.1301 limit of 100 mrem/year.

Reference 24.152 mentioned above, is Technical Support Document (TSD) # 13-009, Member of the Public Dose From All Onsite Sources, Revision 1, which states:

Dose points were evaluated at the South SWYD fence, the North SWYD fence, the new relay house and all 10 of the oil circuit breakers (OCB). The OCBs are dispersed throughout all areas of the SWYD as shown in attached site map. The hourly dose was calculated at each dose point and then all 13 dose points were averaged to develop an average hourly dose rate that applies to all areas of the SWYD. The maximum dose rate at the South Radiological Restricted Area Boundary was determined to apply to the Microwave tower that may be accessed by Comed at any time.

TSD 13-009, Revision 1, goes on to state:

The SWYD and Microwave tower will be monitored by TLDs as part of the site REMP and ODCM and read on a quarterly basis. Comed will be contacted on a quarterly basis to confirm personnel occupancy for areas. Comed personnel dose from direct radiation sources will then be calculated quarterly to ensure compliance with 10 CFR 20 requirements. An annual review will also be performed as part of the REMP and ODCM to again demonstrate compliance with 10 CFR 20.

Thanks,

Justin Wheat Regulatory Affairs Director Call or Text (334) 714-6521 jtwheat@energysolutions.com