ML20072M169

Independent Assessment of Auxiliary Bldg Underpinning Weekly Rept 29, for 830403-09

ML20072M169
Person / Time
Site:	Midland
Issue date:	04/15/1983
From:	Lucks A STONE & WEBSTER, INC.
To:	Cook R NRC
Shared Package
ML20072M111	List: ML20072M134 ML20072M146 ML20072M152 ML20072M169 ML20072M177 ML20072M189 ML20072M205 ML20072M212 ML20072M228
References
MPF-29, NUDOCS 8307140358
Download: ML20072M169 (9)

Text

-- - _ - -

- '- 'J.O.' NO.

Midland Plant 14358' O c3-

• Units 1 and 2 >

Independent Assessment Auxiliary Building Underpinning Weekly Report No. 29 April 3, 1983 through April 9. 1983 Personnel on Site Stone & Webster Michigan, Inc.

-W. Kilker 4/4 4/7 L. Rouen 4/4 - 4/8 A. Scott 4/4 - 4/9

_P. Majeski 4/4 - 4/9 Parsons, Brincke noff Michigan, Inc.

4 J. Ratner 4/4 - 4/8 Meetings Attended.

Purpose t Represented

~

Date 4/4 Stone & Webster (4/5 4/8) Daily Meetings through Bechtel 4/8 Consumers Power Parsons 4/7 Stone & Webster Presentation on

' Bechtel Grillage Beam Consumers Power Installation Procedures Mergentime Parsons 4/8 Stone & Webster Weekly Project Bechtel Soils Meeting Consumers Power Mergentime .

Activities Construction -

Pier W12: The Contractor continued to monitor the. pier settlement and check the shims for tightness. This pier has been'rejacked once since the mandatory rejackings were completed. Approximately 5 mils of structure movement were noted at pier W12Eduring jacking of pier W9 Initial load transfer was accomplished on April-5. The active jacking Pier W9:

mode at-110 percent of specified load began on' April 6 and continued thru the end

~of the week. Deflection of the. bottom of the pier was approximately 0.3 inches as of April 9 while elastic shortening of the pier was on the order of 0.05 inches. Upward movement of the turbine building, as measured by a nearby deep-seated benchmark, was on the order of .02 inches, i

8307140358 830630 PDR ADOCK 05000329 PDR.. ,_ 1

.-0 .

-- -- .- t-- . _ , _ _ . _ _ _ _ _ . , _,

s (% -

' - J.0, NO. 14358 (,)

Midland Plant Units 1 and 2 Independent Assessment Auxiliary Building Underpinning 2 Pier W11: Excavation of the pier was completed and the plywood sheathing anti-friction liner installed. The seepage into the execvation was reduced by grouting the majority of the lagging spaces below the fill-natural soil interface.

Installation of reinforcement started on April 9 Pier E12: The Contractor continued to monitor the pier settlement and check the shias for tightness.

Pier E9: Initial load transfer was accomplished on April 4. The active jacking mode of 110 percent of specified load began on April 4 and continued through the end of the week. Deflection of the bottom of the pier was approximately 0.25 inches inches. Uplift of the as of April 9, while elastic shortening was about 0.04 turbine building was on the order of .03 inches as measured by a nearby benchmark.

Pier Ell: Excavation of the pier shaft and bell was completed. Water seepage entered the excavation over the weekend of April 2-3 due to a shutdown of the sump pump in the access pit to pier E12. Once pumping resumed, the se'epage was virtually eliminated. However, even this minor amountAfter of seepage caused the bracing and supporting soil material in the bell area to begin unravelling.

the long side of the bell area, the Contractor elected to concrete the bell.

During concrete placement serveral additional cubic feet of soil collapsed. The soil and contaminated concrete were removed and the bell pour was completed.

Quality Control, Documentation and Records:

1 Evaluated the proposed engineering response to the NCR written con-cerning approval of concrete mix C5-C.

2. Reviewed preliminary copies of inspection reports for: pier E/W9 bell area concrete placement, pier E9 reinforcing installation, over-inspection for pier E/W9 rebar sol.icin~ snd olacement, and over-inspection for pier E/W9 concrete olacment.

Observations Construction - The load transfer activities at piers E/W9 were performed in a timely and satisfactory manner. The rejacking operations continue to be of some concern to the Assessment Team. The wedges should be driven tight enough to lift a significant portion of the load off the jacks in order to insure full building load transfer to the piers. Also, the Team has observed some irregularities in the size and taper of the steel wedges. The quality of the wedges should be improved to insure full and uniform bearing.

Concerns of the Assessment Team with regard to backpacking operations led to a meeting at the pier E11 excavation on Acril 7 attended by representatives of the Contractor, Subcontractor and Resident Engineering. Specifically the

! Assessment Team concerns were: (1) over the use of fine sand in areas of seepage l

and (2) the effect of narrow lagging spacing and full backpacking of the louver spa'ce between lagging sets on the final quality of backpacking and the ability to adequately perform an inspection. It is the opinion of the Assessment Team that the quality of future backpacking would be improved by the use of a more appropriately graded material for wet conditions and that the lagging spacing should be wide enough to permit easier placement of the backpacking material and inspection of the final product. Also, the packing of the louver spacing between lagging serves no useful purpose and may actually encourage arching of the soil behind the lagging as well as impeding inspection.

--n - n - -

,- ,J.O. NO. 14358 Midland Plant (V) g(-)s, .

Units 1 and 2 Independent Assessment Auxiliary Building Underpinning 3 The Contractor displayed good judgment in supporting the tell area of pier E11 and in electing to concrete the bell area prior to readying the pier shaft for concrete Delays would have resulted in the further soil unravelling and the need for more sheeting support. The Contractor's reaction to the collapse of additional soil during concrete placement was appropriate resulting in a satisfactory pier bell.

Quality Control, Documentation and Records - The concerns of the Assessment Team stated in NIR #5 were adequately addressed by the proposed Project Engineering response. The NIR will be closed pending closure of the corresponding MPOAD NCE.

The inspection reports reviewed by the Assessment Team adequately document ecm-pliance with the applicable procedures.

Non-Conformance Identification Reports Status of previous issues: (NIR numbers on longer listed have been closed-out.)

NIR NO. Description Date (0pened) (Closed) 5 Concrete Mix 2/10/83 Qualification 6 Lagging Spacers 3/21/83 7 Backpacking Material 4/5/83 in Wet areas-Pier W11 8 Load Transfer Methodology- 4 / 5/83 Pier E12

(,/ ,. . tu; kb b t.. x Project Engineer Project Manager l

l i

• R Q

s

. (~~)

%J DAILY INDEPE!! DENT ASSESSMENT TEAM MEETING Date: April 4, 1983 Stone / Webster __ MPCAD CPCo Attendees: Bechtel E. Cviki -------------- R. Sevo R. Wieland J. Gaydos Parsons J. Ratner

1. E. Cvikl will discuss with R. Oliver of MPOAD the engineering response to the QAR on the concrete mix design,

2. E. Cvikl reported that load transfer on pier E9 began today. Pier W9 load transfer is expected on April 5.

3 The Mergentime presentation on grillage beam installation is scheduled for this week.

4 The results of the drypack grout sample testing on piers E/W9 leveling plates will be available today. J. Gaydos will supply.

5 J. Ratner questioned why in backpacking, the material is packed nearly out to the front face of the lagging since the inspection of the conditions behind the sheets is hindered by this material. FSO will respond.

6. E. Cvikl reported that Project Engineering feels as-built drawings of the structural components of the unterpinning are not required as long as things are done within document tolerances and that changes are covered by FCRs and DCNs. However, soil foundation condition descriptions are required as a "close-out" of the underpinning work.

7. J. Ratner questioned why a certain percentage (on the order of 10-15 percent) of the jack load is not picked up by the wedges during the rejacking operations as is in keeping with good underpinning practice.

i i

i

. .. (s _- ) .

DAILY INDEPENDENT ASSESSMENT TEAM MEETING Date: April 5, 1983 Attendees: Bechtel Stone / Webster MPOAD CPCo J. Fisher A. Scott R. Sevo D. Puhalla E. Cviki L. Rouen J. Gaydos Parsons J. Ratner

1. L. Rouen has contacted E. Cvikl concerning concrete mix C-5C. Resolution of the Project Engineering response on the NCR will be handled by E. Cviki and R. Oliver.

2. The Assessment Team will be informed of the time for review of installation plans for the grillage beams at pier 6 by Mergentime some day this week.

3 J. Fisher stated that E9 pier load transfer was in the phase of .01 settlement per 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and this limit should be attained by tomorrow morning. Load transfer for W9 pier will start today.

4. J. Gaydos reported that the drypack test cubes molded on March 31 showed similar results for slab made cubes by bcth Mergentime and U.S. Testing for 1 and 3 day tests, but the 1 day test made by U.S. Testing lab on the table were 20% lower than those made on slab.

5 J. Ratner reiterated that backpacking with fine sand in wet areas was not good underpinning practice. J. Fisher to investigate.why action was not taken to correct.

6. E/W8 pier and drift design review package is to be given CPCo this week upon receipt of Shop Drawings.

7. D. Pullalla supplied excerpts from the SSER which were marked to indicate what was required in the way of detailed as-builts of the underpinning effort. J. Fisher stated that were keeping necessary records to satisfy the committments of the SSER, FSO and Project Engineering.

(~)

v DAILY INDEPENDENT ASSESSMENT TEAM MPETING Date: April 6, 1983 Bechtel Stone / Webster M?QAD CPCo Attendees:

J. Fisher L. Rouen R. Sevo G. Murray E. Cvikl A. Scott J. Kelleher W. Kilker P. Majeski Parsons J. Ratner

1. W. Kilker advised that the disapproval of the FCE on the concrete mix design C-5C was sufficient to allow NIR #5 to be closed.

2. J. Fisher advised that grillage team installation procedure presentation was scheduled for April 7.

3 There was a general discussion of Assessment Team concerns with respect to backpacking. (a) The method of placement of the backpacking material and possibly the width of the lagging spacing has at times impeded complete backpacking of void spaces behind the lagging. (b) The use of a fire grained sand as backpacking material in wet areas is not the best practice. All concerned parties will meet at pier E11 6 11AM to discuss and resolve concerns.

4. G. Murray said the E/W8 design package may go to NRC April 7

5. G. Murray will advise on what the commitments are to produce underpinning as-built documents. The question is as to what extent the foundations are included as opposed to the soil foundation material.

6. W. Kilker advised that the Assessment Team has issued an NIR on the observed method of assuring full load transfer when rejacking the piers. MPQAD will issue a QAR to initiate FSO response.

A e

es r \ s\

. . . I x,)

QJ DAILY INDEPENDENT ASSESSMENT TEAM MEETING Date: April 7, 1983 Attendees: Eechtel Stone / Webster MPQAD CPCo J. Fisher L. Rouen J. Shah G. Murray E. Cvik1 A. Scott J . McMaster P. Majeski Parsons J.-Ratner

1. The Assessment Team indicated that Mergentime's presentation on April 7 regarding installation of the grillage beams at pier 8 provided the information currently required.

2. J. Ratner and A. Scott indicated that Team members met with representative of Field Engineering, Resident Engineering, MPQAD, and Mergentime at pier E11 on April 6. The concerns raised in the daily meeting of April 6 over the backpacking material grain size in wet areas and the louver spacing effect on the final backpacking productwere satisfactorily addressed.

3 G. Murray indicated that drawing "as-builts" of underpinning effort will be the same as those for balance of plant; that is, changes are required when there is a FCN or FCR written against a drawing, l

'A (^)

Nj g -'s O

l l

l DAILY INDEPENDENT ASSESSMENT TEAM MEETING Date: April 3, 1983 Attendees: Bechtel Stone / Webster MPQAD C?Go J. Fisher L. Rouen J. Shah G. Murray E. Cvikl A. Scott J. Gaydos Parsons J. Ratner

1. J. Fisher stated that two shifts are scheduled to work Saturday on E/W8 and E/W11. Also it is possible that the pier E11 bell will be poured Saturday.

2. J. Ratner asked if the plate supporting the E11 bell excavation would be grouted prior to placement of concrete. J. Fisher stated it would be either grouted or removed prior to placement.

3 J. Gaydos said that mixes with plasticizer have been developed and now await approval by Bechtel San Francisco office.

.- a. O o STONE & WEBSTER MICHIGAN, INC.

P.O. Box 2325, BOSTON. M ASSACHUSETTS O2107 United States Nuclear Regulatory Commission April 15, 1983 Midland Site Resident Inspection Office Route 7 J.0 No. 14358 Midland, MI 48640 Ref. MPF 29 Attention Mr. R. Cook RE: DOCKET NO. 50-329/330 MIDLAND PLANT - UNITS 1 and 2 INDEPENDENT ASSESSMENT OF A'lXILIARY BUILDING UNDERPINNING REPORT NO. 29 A copy _of the Independent Assessment of the Auxiliary Building Underpinning Weekly Report No. 29 for the period April 3, 1983 through April 9, 1983, is enclosed with this letter. Included as attachments, are the minutes of the daily meetings held during the week between members of the Assessment Team and Site Engineering, Construction, and Quality Assurance personnel.

If you have any questions with respect to this report, please contact me at (617) 589-2067.

Very truly yours, f $ h>b2 I %t A. Stanley Lucks Project Manager Enclosures ASL/ka APR 3 g gggg

. .- . . -- -.