ML20058J549
| ML20058J549 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 08/09/1982 |
| From: | Devincentis J PUBLIC SERVICE CO. OF NEW HAMPSHIRE, YANKEE ATOMIC ELECTRIC CO. |
| To: | Miraglia F Office of Nuclear Reactor Regulation |
| References | |
| SBN-304, NUDOCS 8208110102 | |
| Download: ML20058J549 (2) | |
Text
PUBLIC SERVICE SEABROM STAM raein ine omw.
Companyof NewW 1671 Worcest.r Road Framinchom, Mossochusetts 01701 (617) - 872 - 8100 August 9, 1982 SBN - 304 T.F. B 7.1.2 United States Nuclear Regulatory Commission Washington, D. C. 20555 Attention:
Mr. Frank J. Miraglia, Chief Licensing Branch No. 3 Division of Licensing
References:
(a) Construction Permit CPPR-135 and CPPR-136, Docket Nos. 50-443 and 50-444
Subject:
Revision to FSAR Section 12.4.3
Dear Sir:
A review has teen perforced on Section 12.4.3 (" Estimated Dose to Construction Workers") of the Seabrook Final Safet y Analysis Report (FSAR) with the result that we have revised the estimated L.ca1 radiation dose to Unit 2 construction personnel during operation of Unit I and have also included the a8Fregate dose to Unit 2 construction personnel.
We have attached the revised FSAR Section 12.4.3 which will be incorporated i
into Amendment 46 of the Seabrook OL Application.
Very truly yours, YANKEE ATOMIC ELECTRIC COMPANY J. DeVincentis Project Manager l
I D D F208110102 820809 FDR ADOCK 05000443 I
i A
PDR 1
-.a i
12.4.3 Estincted Doze to Constructicn Workers i
l
'Once Unit I reaches full power operation, it is expected that a few additional i
years of construction will be required to complete Unit 2.
The remaining construction work force onsite will directly benefit from all of the plant design features and procedures employed to minimize doses to the operating personnel of Unit 1 and the general public.
The total dose to the construction workers will be the sum of the dose contributions from the releases of gaseous radioactivity from Unit 1 and from contained sources. Of the two contributions, the dose from the contained sources will dominate (the dose estimates for gaseous releases provided in Subsection 11.3.3 clearly indicate that the doses to the construction workers from this source are well below the Ifmits specified in 10CFR20 for the exposure of occupationally employed individuals in unrestricted areas). The maximur dose rate from contained sources in yard areas which are frequently occupied by plant personnel is, by design, less than 0.5 mrem / hour (Section 12.3.2).
The maximum dose received by a construction worker, who can te expected to spend, at the most, 50% of his time outdoors in the yard area, will be less than 500 mrem for a full year (2,000 man-hcurs). The estimated average annual dose to a Seabrook construction worker during full power operation of Unit 1 is 0.0235 rem.
The basis cf this estimate is as follows: Most of the construction activity which occurs after the startup of Unit I will be inside of the Unit 2 structures and the average worker is expected to spend only 15% of the workday outdoors. When a worker is outdoors, it is expected that his average dose rate will be approximately one-tenth (0.1) of the maximum dose rate for Zone I radiation areas, i.e., 0.05 mrem /hr.
(Each Seabrook unit has a double containment, and as a result of this design feature, the direct radiation from the major confined sources is considerably reduced.) When employed on tasks in the interior of Unit 2, the construction workers will benefit from the substantial radiation shielding provided by the equipment and the structural eierents of Unit 2.
It is estimated that the average dose to contractors in Unit 2 during the final stages of construction will be approximately equal to the radiation dose rate at the site boundary of Unit 1, or 0.005 mrer/hr (see Table 12.3-2). It follows that the estimated average annual dose a construction worker will receive is 0.15 x 0.05 mrer/ hour x 2000 man-hours /
year + 0.85 x 0.005 mrem / hour x 2000 man-hours / year = 0.0235 rem.
l The size of the work force associated with the construction of Unit 2 can te expected to vary with the stage of construction. It is estimated that after the startup of Unit 1, the number of manual and nonmanual personnel associated with Unit 2 will average about 4,300 for the first year, 3,500 for the set nd year, and 2,000 for tFe first quarter of :Se third year at which point commercial operation of Unit 2 is expected. Sirce the average annual dose to a Unit 2 construction worker le given as 0.0235 rem, the total radiation dose to the entire Unit 2 construction force would be:
(4,300 man-year x 0.0235 i
rem / year) + (3,500 man year x 0.0235 rem / year) + (2,000 man year x 0.0059 rem / year) or 195 man tem.
l
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