ML20040G023
| ML20040G023 | |
| Person / Time | |
|---|---|
| Site: | Midland |
| Issue date: | 02/04/1982 |
| From: | Jackie Cook CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| 15528, NUDOCS 8202110105 | |
| Download: ML20040G023 (3) | |
Text
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Consumers power James W Cook Vice President - Projects, Engineenng and Construction General of fices: 1945 West Parnell Road, Jackson, MI 49201 * ($17) 788 0453 February 4, 1982 Harold R Denton, Director Office of Nuclear Reactor Regulation S
US Nuclear Regulatory Commission g
7 Ddi?/(fD p Washington, DC 20555 Il %g,c MIDLAND PROJECT
'S MIDLAND DOCKET NOS 50-329, 50-330 y
g g
AUXILIARY BUILDING SOIL REMEDIAL MEASURES ACCESS g
SifAFT - AUGERING METHOD FOR SOLDIER PILE HOLES p
FILE 0485.16 SERIAL 15528
REFERENCE:
MIDLAND SOILS HEARING TRANSCRIPT ON PAGES 5675, 5767, 5769 AND 5770 ENCLOSURE: ACCESS SHAFT SOLDIER PILE INSTALLATION PROCEDURE In response to Administrative Judge Harbour's concerns expressed during the referenced hearings concerning the possibility of soils movement into the augered holes, witnesses Ed Burke and J Gould stated that hollow stem augers would be used for drilling the soldier pile holes in the access shaft area.
They also briefly presented details of the equipment and procedure at the hearings.
Subsequently, we have reviewed the use of hollow stem augers considering the expected soil conditions in the/ access shaft area. The torque capacity of the hollow stem auger is low.
Ther% fore, it is our judgement that we will have great difficulty in drilling the holes in the till from Elevation 580'-0 " to Elevation 561'-0."
There is also a possibility of fill concrete being present in the area where these holes are to be drilled. The hollow stem auger will be ineffective in drilling the holes through the concrete because of its limited down pressure capacity.
Considering the above diffletlties in the use of the hollow stem auger, we now intend to use a solid stem auger, which has a high torque and down pressure capacity, using the alternate procedure ideatified in the enclosure. This alternate procedure resolves the concerns expressed by Administrative Judge Harbour in the referenced hearing.
The enclosed procedure and the reasons for its use were discussed with the Staff in Ann Arbor during the NRC audit on January 19, 1982. The Staff was concerned that there would be difficulty in using a hollow stem auger and indicated that they had no objections to the employment of a solid stem auger oc0182-0019a100 gl 8202110105 820204 r
PDR ADOCK 05000329 3I l
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2 using the enclosed alternate procedure. The Staff also concurred that the alternate procedure will prevent the movement of soils into the augered hole.
We, therefore, plan to use the enclosed alternate procedure using the solid stem auger instead of the hollow stem auger, thereby changing the plans as discussed at the earlier hearings. This letter formally documents what was briefly conveyed to the Hearing Board on February 2, 1982.
owsW.
JWC/RLT/dsb CC Atomic Safety and Licensing Appeal Board, w/a CBechhoefer, ASLB, w/a MMCherry, Esq, w/a FPCowan, ASLB, w/a RJCook, Midland Resident Inspector, w/a RSDecker, ASLB, w/a Jharbour, ASLB, w/a DSHood, NRC, w/a (2)
DFJudd, B&W, w/a JDKane, NRC, w/a FJKelley, Esq, w/a RBLandsman, NRC Region III, w/a WHMarshall, Esq, w/a JPMatra, Naval Surface Weapons Center, w/a W0tto, Army Corps of Engineers, w/a WDPaton, Esq, w/a SJPoulos,Geotechnical Engineering, w/a FRinaldi, NRC, w/a HSingh, Army Corps of Engineers, w/a BStamiris, w/a oc0182-0019a100
ENCLOSURE ACCESS SHAPI SOLDIER FILE INSTALLATION PROCEDURE 1.
Hole vill be augered using a solid stem auger driven by a Kelly bar.
Cutting teeth of the auger vill be 2 inches larger in radius than auger flights.
2.
Bentonite clurry will be added when the hole has reached 10 feet, in depth.
i 3.
If an obstruction is encountered, a 30 inch casing vill be installed to the obstruction and the obstruction vill be removed by chopping or coring.
h.
When the hole has reached design depth, the pile vill be inserted and h000 psi concrete vill be placed by tremie to a depth of 10' in the hole bottom.
5 The remainder of the hole vill be filled with a flyash/ cement mixture placed by pump tremie methods.
The use of bentonite slurry or casing vill insure the stability of the hole during augering and installation. Adjacent piles vill not be installed simultaneously.
1/29/82 c
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