ML19350D803

Final Deficiency Rept,Initially Reported 810414,re Nonconforming Concrete,Rebar & Bolt Coupler Placement in Fuel Bldg.Caused by Personnel Error & Misinterpreting Drawings.Slab Will Be Repoured by 810529

ML19350D803
Person / Time
Site:	Yellow Creek
Issue date:	05/14/1981
From:	Mills L TENNESSEE VALLEY AUTHORITY
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
10CFR-050.55E, 10CFR-50.55E, YCRD-50-566-81, NUDOCS 8105190362
Download: ML19350D803 (2)

Text

..

TENNE 9SEE '/ ALLEY AUTHC o 'Y zw rnc- c -, cc:. . : u t : . :.,

i 400 Chestnut Street Tower II l

\

' May 14, 1981 l , . .. L-

.s C

YCRD-50-566/B1-14 Q ~j

.: N % et s}N  ?

A R5 5

~

65 Mr. J P. O'Reilly, Director ,- ;g  ? -

Office o Inspection and Enforcement  !/

U.S. Nir:1 Regulatory renwission - g hh,, '

/

aegion II - ite 3100 ',

t =

101 Marietta treet /g>

Atlanta, Geor 30303 -

Dear Mr. O'Reilly:

YELIOf CREEK NDCLEMt PIANP IJNIT 1 - CINCREIE PLACEMENT - FU!L BUIIDING -

YCRD-50-566/81 FINAL REPORP

'Ihe subject deficiency was initially reported to NIC-CIE Ismpad.Or D. Quick on April 14, 1981 in accordance with 10 CFR 50.55(e) as NCR YC-152Rl. Enclosed is our final report.

! If you have any questions concernirs this satter, please get in touch with D. L. Lambert at FIS 857-2581.

Very Wy yours, m VARI n AurgmITr m

l L. M. lis, Manager Nuclear tion arr! Safety Ehclosure I oca Mr. Victor Stello, Jr., Director (Ehclosure)

Office of Inspection aC Enforossent U.S. Nuclear Regulatory Ocmunissica Washington, DC 20555 A

• 1 8195190362 w

---

.-------l ._- - - - -

o O

ENCICSURE 1

YELIOf CREEK M) CLEAR PIANP UNIT 1 CCNCRETE PLACEMENT - EUEL BUIIDIE 10 CFR 50.55(e)

YCRD-50-566/81-14 FINAL REPORP Description of Deficiency Nonconformance report (NCR) No. YC-152R1 was made significant and reportable because it involves significant rework of a safety-related structure. his NCR involves concrete, rebar, and bolt coupler placement in the unit 1 Fuel Building in concrete pour No. F1-N1. Se top grade of the nonconforming area of the pour (5.02 ft x 5.52 ft) should have been poured to elevation 507.0 but was poured to 507.5 (slab grade) instead, while the bottan elevation was poured to 506.0 (bottan of slab) instead of 505.0. Consequently, the associated rebar was mislocated. Ebur bolt couplers were also left out of the pour. Rese deficiencies were discovered after concrete placement by project engineers while planning and laying out e.k for adjacent pours. W e error was because of craftsmen, project engineers, and quality control inspectors misinterpreting the drawings.

Safety Inplications Had this condition renained uncorrected, the deficient concrete placement in the Fuel Building could jeopardize the structural integrity of the Fuel Building, thus adversely affecting the safe operatten of the plant.

Corrective Action We nonconforming condition was evaluated by '1VA's Division of Engineering Design (EN DES) . EN DES's disposition was to (1) chip out the excess concrete, (2) portition rebar to conply with design drawings, (3) install the four missing bolt couplers, and (4) -repour the slab to proper elevation as shown on the design drawings.

'Ib preclude a recurrence, additional independent reviews of the rebar inspection takeoff checklist were inplemented immediately by Civil-Quality Control. Also, craft faremen will verify proper installation with their fabrication checklists. Project engineers were instructed to make a thorough study of all drawings before checking the pours.

W e excess concrete has been chipped out. Se rebar should be relccated, bolt couplers installed, and the slab repoured by May 29, 1981.

Other TVA nuclear plants are not affected by this deficiency.

I a

.- - . - . . r , __ - - ..- -