ML19260E876
| ML19260E876 | |
| Person / Time | |
|---|---|
| Site: | Pilgrim |
| Issue date: | 05/20/1980 |
| From: | Jachowski R ARMY, DEPT. OF |
| To: | Johnson T Office of Nuclear Reactor Regulation |
| References | |
| NUDOCS 8008080627 | |
| Download: ML19260E876 (2) | |
Text
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4 DEPARTME iT OF THE ARMY MM COASTAL ENGINEERING RESEARCil CENTER 1
Ni CORF5 0F ENGINEER 4 KING %1AN Bt'ILDING FORT BELVOIR, VIRGINIA 22060 CEREN-CD 20 May 1980 Mr. T. Johnsen Hydrologic Engineering Section U.S. Nuclear Regulatory Commission Washingten, DC 20555
Dear Mr. Johnson:
Pursuant to our phone conversaticn, pertaining to breakwater damage at Boston Edison Company's (BECo), Pilgrim Station, I have reviewed the data you subsequently provided with the BECo letter No. 80-66 dated 15 April 1980. It was determined that the shore-connected rubble-mound breakwater at the Pilgrim Plant experienced extreme water level and wave action con-ditions on three occasiens, 6-7 February 1978, 25 January 1979, and 25-26 February 1979.
The information presented by BEco provides sufficient data to evaluate the cause and effect of the damages to the Pilgrim Station Breakwater re-sulting from ;he above cited storms.
I concur in the general conclusions and reco==endations presentec by BECo in the referenced letter and ree-ommend that the following steps be implemented regarding the breakwater:
1.
Establish a continuing monitoring program for the purpose of determining if movement of the armor stone or damage has occured to the seaward face, crest, or landward face armor stone of the breakwater.
This should be an annual program and supplemented, as necessary, after any severe storm. The monitoring program could consist of a photograph-ic record similar to Exhibit 1 accompanying BECo letter No. 80-66, a series cf vertical aerial photographs of the breakwater, and a comparative analysis or photographs with previous years to determine if armor stone have moved or been displaced. A report should be filed based on the results of this analysis.
2.
If damage is detected, which effects the stability of the struc-ture and its safety related function, repairs should be implemented, as soon as possible, following the storm and subsequent analysis.
3.
When damage occurs to the structure where the existing armor stone does not meet the design weight requirements, the armor stone should be replaced with quarrystone meeting the design requirements. Further, if damage occurs to a previously repaired section, displaced armor stone should be removed from the structure and replaced with new design weight quarrystone.
80080 80 b7
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CEREN-CD 20 May 1980 Mr. T. Johnson 4.
A follow up report on breakwater repairs should be filed indicat-ing the extent of damage and the procedures used to effect cepairs.
As you requested, I am returning the BECo letts.c and appended exhibits.
If you have any further questions pertaining to the water please do net hesitate to contact me.
Sincerely, r
k $,
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1 Incl ROBERT A. J3CHOWSKI As stated Chief, Coastal Design Criteria Branch 2
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