ML20137G975
| ML20137G975 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 07/05/1979 |
| From: | TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| To: | |
| Shared Package | |
| ML17198A292 | List:
|
| References | |
| FOIA-85-59 QI-QP-11.0-4, NUDOCS 8512020294 | |
| Download: ML20137G975 (4) | |
Text
~
f.;.
(
e TEAS Uf!LITIES GENERATING CO.
INSTRUCTION ISSUE NB%ER RWISIM PAGC
'CPSES DATE -
[
QI-QP-11.0-4 2
7-5-79 1 of 4 SUM!!ER CONCRETE PREPARED BY:
M// W*p_7/f//f OR MORTAR CURING DATH INSPECTION 7!J/79 APPROVED BY.
1.0 REFERENCES
1-A Specification -2323-SS-9 2.0 GENERAL
'[na TFORIETiBH DH
~
r 2.1 PURPOSE AND SCOPE UR ls1 To outline the inspection requirements for summer curing of all safety related concrete or mortar placements.
3.0 INSTRUCTION 3.1 ACCEPTABLE CURING METHODS 3.1.1 Surfaces Not In Contact With Forms For surfaces not in contact with forms, verify that one of the following methods is put into effect,immediately after placement:
a.
Ponding or continuous sprinkling.
b.
Absorbent mats kept continually wet.
c.
Sand kept continuously wet.
d.
Continuous steam (not exceeding 150 F) or spray mist.
e.
Waterproof sheet material.
f.
Curing compound if approved by Engineer.
851202O294 851106 PDR b
meen aa
INSTRUCTION 4
ISSUE Tc~.XAS UTILITIES m..NG CO.
IDIBER PAGE CPSES 7S QI-QP-11.0-4 2
7 3_79 2 of 4 U
3.1.2 Surfaces in Contact with Forms Metal forms in contact with placement surface are acceptable a.
for moist curing.'
b.
Wood forms in contact with placement surface are not acceptable for moist curing.
3.1.3 Change in Curing Methods
'Any acceptable curing method may be replace by one of the others after the placement is 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> old, provided the placement is not allowed to become surface dry during the transition.
3.2 CURING INSPECTION REQUIREMENTS 3.2.1 Containment Exterior Walls and Foundation Mats in Excess of 2'6" Verify that placement surfaces are protected form premature a.
drying.
b.
Verify that construction joints are kept continuously vet.
/~'
The method of curing employed must contain moisture within c.
the placement for 14 days, d.
Verify that forms and exposed surfaces are kept vet for the first 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> after placing and any time during the curing period when the ambient temperature is above 90 F.
3.2.2 Other Placements Requiring Seven Day Minimum Cure Placement surfaces must be protected from premature drying.
l a.
b.
Construction joints must be kept continuously wet.
The method of curing employed must maintain moisture within I
c.
the placement for 7 days.
d.
The rate of air temperature change immediately adjacent to.
O 0
the placement must not exceed S F in any one hour or 50 F l
in any 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />.
8 kJ 0
+,
Il!SITUCTION g f/
ISSUE TEXAS UTILITIES GE N S;G CO.
h11IBER g
CPSES f(
QI-QP-11.0-4 2
i 7-5-79 3 Of 4 3.2.3 Field Cured Cylinders Verify that field cured cylinders are placed in or on the structure as near to the point of use as possible, and receive-the same protection and curing as the placement they represent.
3.2.4 Surface Temperature Requirements There are no specific temperature limits, and no placement surface temperature will be taken.
3.2.5 Protection from Mechanical Injury During the curing period, verify that placement is not a.
subjectec to load stresses, heavy shock and excessive vibration.
b.
Verify that finished surfa:es receive adequate protection from materials and equipment.
3.3 DOCUMD;TATION METHODS 3.3.1 Daily Inspection Verification 7_
f 8
'% /
The QC Inspector will verify daily curing inspection by initialing and dating Figure 1.
At the end of the required curing period, he will sign this form andifo'rward to the Civil Inspector' Supervisor / designee for review, processing and filing in accordance with CPSES requirements for "QA Records".
~
e e
e A
sJ s
e f -
..=
(
INSIEUCTION ggy(?i-ISSUE EE UTILITIES GENERLJG CO.
tREER pg
[
91-qp-11.0-4 2
7-5-79 4 og 4 t
FIGURE I Pase _ of_
l I;
DATI.Y CITRING VERIFICATTON Pour No: _
5tructure:
Pour Date: _
Placement Temp. Range:
Type of Cure:
T3_= of Torn Re:ionl:
Thermometer No:
"EITd3ED CUMIC WIN AFFLICAILE DAY 1
2 3
4 5
6 7
8 9 ~
10 11 12 13 14 INITIALS
(
me Note:
Wen curing cocpound is used, check integrity of application by vetting surface with water.
beads, the curin;; fil::: is adequate.If the water forms droplets or Coments:
l Date 6
Q.C. Inspector
^
l 2,,_
.---y-W)
.g.
.e+
l co l* -
U. S. NUCLEAR REGllATORY CO.T:ISSION f
0FTICE OF INSPECIl0N A';D ENFORCEMENT REC 10N IV Eeport No. 50-445/79-26; 50-446/79-25 Docket No. 50-445; 50-446 Category A2 Licensee:
Texas Utilities Generating Company 2001 Bryan Tower Dallas, Texas 75201 Tacility Na:e:
Comanche Peak, Units 1 & 2 Investigation at:
Comanche Peak Steam Electric Station, Glen Rose, Texas Investigation conducted:
October 11-22, 1979 Inspector: M. f ? Mud-aMs
//[S/79
[ R. G. Ta'l lor, Resident Reactor Inspector, Projects Date Section Approved:
k
//[8[79 e
k'. A. Crossman, Chief, Projects Section Date Investigation Summarv:
Investication on October 11-22. 1979 (Report No. 50-445/79-26; 50-446/79-25)
Areas Investicated:
Special investigation of allegations by a former site construction worker of improprieties in the civil construction phase of this facility. The investigation involved ten inspector-hours by one NRC inspector.
Results: Three of the allegations were determined to be factual, but without merit since they had been detected and corrected within the licensee's QA program.
One allegation had no merit and one could be neither substantiated nor refuted.
cps 3rfi1W1 u
i INTRODUCTION Co=anche Peak Sten: Electric Station (CPSES), Units 1 and 2 are under con-struction in Somervell County, Texas, near the town of Glen Rose, Texas.
Texas Utilities Generating Company is the Construction Permit holder with Brown and Root, Inc. as the Constructor and Gibbs and Hill, Inc. as the Architect / Engineer.
REASON FOR INVESTICATION A person who visited the Region IV office made allegations of construction improprieties at the Comanche Peak Stat' ion.
SUMMARY
OF FACTS A person who identified himself as a former Brown & Root employee visited the Region IV office at approximately 4:00 p.m. on October 9, 1979.
The person stated that he wished to discuss deficiencies in safety-related construction at the Comanche Peak Station. The person was then interviewed by personnel of the Region IV, Reactor Construction and Engineering Support Branch. The interview developed the following allegations:
Allegation 1:
C
[k,1b )
In the. Unit 1 Auxiliary Building at elevation 807', rebar was omitted in four co'lu=ns in the EA vall! The alleger stated that he had acquired the information from his general' foreman and that site engineering personnel (names unknown) were aware of the omission.
Allegation 2:
In the Unit 1 Auxiliary Building, the concrete slab acting as the ceiling above elevation (floor) at 832', in the area just before entry into the Unit 1 Safeguards Building, had a 20' x 20' honeycomb area which was exposed upon concrete form removal.
The alleger indicated that he was aware of the corrective action taken, but felt it had been simply dry-packed.
Allegation 3:
In Unit 1 Containment, there had been a mixup in anchor bolts.
The alleger indicated that 3000 anchor bolts had been interchanged, some having been furnished by " Boston Made" and others by " Southern Ibde."
Allegation 4.a:
There is general cracking of floor slab concrete in the plant buildings.
Allegation 4.b:
.$f Horizontal tie rebar was omitted in Unit 1 Containment / Containment Wall.
L.
CONCLUSIONS The following conclusions are based on review of various documents, technical literature, and observations by the NRC Resident Reactor Inspector.
Supporting documentation for these conclusions are referenced in the attached details.
Allegations 1, 2 and 3:
These allegations were found to be based on factual events that had been detected and documented within the context of the licensee's Quality
{gC ' q) \\
Assurance system as required by Appendix B to 10 CFR 50.
Two of three alleged events were corrected in accordance with sound engineering practices, while the third was evaluated by the engineer and found to be adequate in the "as is" condition.
Allegation 4.a:
This allegation has no apparent merit. Hairline surface cracks in concrete are not considered to have any effect on structural integrity.
A11ecation 4.b:
This allegation could neither be substantiated nor refuted based on avail-able evidence but is thought :to refer to an event involving the omission
(.-
of horizontal ties in the upper part of the Unit 2 Containment wall which is discussed in Inspection Report No. 50-445/79-18; 50-446/79-18.
4 i
4.
DETAILS I
1.
Persons Contacted Allegtr - A person, referred to as the alleger in the text of this report, who was previously employed by Brown & Root (B&R) at CPSES.
Princinal Licensee Emnloyees Site Quality Assurance Supervisor Site Resident Manager Principal Brown & Root Employees Site Chief of Security 2.
Background Information At approximately 4:00 on October 9, 1979, a former Brown & Root employee
" walked-in" to the RIV office indicating that he had allegations regarding deficiencies in safety-related construction at Comanche Peak. During the ensuing interview, the following specific allegations were obtained:
In the Unit 1 Auxiliary Building at elevation 807', rebar was omitted a.
^ -
in four colu=ns in the EA wall.
This construction was co=pleted in
( 7 [) )
early 1978, probably in March or April.
The omission of a portion of the prescribed rebar was reported to him by his rebar General Foreman.
He also indicated that a Gibbs & Hill (G6H) or B&R engineer also was j
aware of the omission; however, he could not recall his name.
b.
Also, in the Unit 1 Upper Auxiliary Building, the concrete slab poured for the ceiling above the elevation 832' level, in the area just before entry into Safeguards Building 1, had a 20' x 20' honeycomb area which was exposed upon removal of forms. He was not aware of corrective action taken; however, he felt that it had simply been dry-packed.
This placement was made in August or September of 1978.
1 c.
In Unit 1 Containment, there had been a mixup in anchor bolts. He indicated that 3000 anchor bolts had been interchanged, some having been furnished by " Boston Made" and.others by " Southern Made."
4 d.
Two unsupported general allegations were also made regarding general cracking of floor slab concrete in the plant buildings and omitted
-horizontal tie rebar in'the Unit 1 Containment wall. Without specifics, the alleg'er was advised that these could not be pursued.
3.
Investigation The above allegations were forwarded to the NRC Resident Reactor Inspector (hRI) at CPSES for review and investigation.
The RRI obtained and reviewed the Bross & Root personnel file on the alleger to establish that the alleger i
I
_4
. ~ ~.
.e.=.
.,s
. r r.- r --
.,,s.
,n
,,,n.
could reasonably have some knowledge of the a13cred improprieties.
It was established that he had been empicyed at the site during the occurrence of most or all of the alleged incidents.
The RR1 discussed the allegations with the site QA Supervisor who then informed the RRI that essentially the same allegations had been telephoned to the President of TUSl/TUGC0 by the alleger on October 4, 1979. The allegations received by the President of TUSI/TUGC0 were forwarded through Ifcensee management channels to the Resident Manager for investigation.
An interview of the Resident Manager indicated that allegations 1 and 2 made to the NRC vere the same as two made to the licensee.
The alleger apparently did not restate allegations 3 and 4 to the licensee but added two others involving a scheme for pilferage of "consumables";
i.e., non-safety material such as lumber and ice chests.
The licensee's site QA Supervisor was found to have initiated a search for data relating to allegations 1 and 2 based on the comparable allegations made to the President of TUSI/TUCCO.
His search revealed two Brown and Root Nonconformance Reports (NCRs) bearing directly on allegations 1 and t
2.
These vill be discussed later in this report.
The RRI asked that a comparable search be initiated relative to allegations 3 and 4 received by the NRC. A complete document package on allegation 3 was immediately offered to the RR1 covering allegation 3.
The search relative to allegation 4 was not possible due to the lack of specificity.
4.
Analysis of Allegations Allegation 1:
0=ission of Reinforcing Steel from Colu=ns in the Unit 1 Auxiliary Building T
Reference to design drawings revealed that there are only four columns in the EA vall of the Auxiliary Building.
(See Figure 1,2-33 of the FSAR) These colu=ns, as well as the entire EA wall, extend virtually from the building foundation to the roof. Brown and Root NCR C-806, dated October 27, 1977, stated that it had been discovered, while erecting reinforcing steel for the EA vall above elevation 831', that reinforcing steel in-four columns had been omitted in the preceding CAg erection activity; i.e., between elevation 807' through-831'. The
(_,, I) d NCR stated that twelve bars, each one inch in diameter, were omitted froa each colu=n and that four separate earlier concrete placements fA vere involved during a period from May through October 1977.
The NCR information uns submitted to the Architect / Engineer for resolution which was provided by Design Change / Design Deviation Authorization No.
486, dated Nove=ber 1, 1977, authorizing not only the omission of the steel between 807' and 831' elevation, but further directing that it be omitted in the balance of the columns through elevation 873'.
The engineer stated that the omission of the steel would still allow the colu=n to accept all design loads with adequate margins. The RRI reviewed 'the involved design detail drawing in conjunction with this analysis and determined that the omitted steel constituted 50% of the vertical. steel on one of the four column faces and that the remaining steel is of the same spacing as the comparable steel in the wall face continuing from column to column.
1.
The only unaccounted for disparity between the allegation and the referenced NCR is that of dates of occurrence, a difference of five to six months.
The RR1 has concluded that the the allegation and the NCR are related to the same event since the allegation, as stated,
[,$h~h was hearsay information and the construction of the columns involved was a one time event. Therefore the alleged time frame is in error.
The RRI had no further questions regarding this allegation.
A11ecation 2: Honeycomb in Concrete Slab in the Unit 1 Auxiliary Building The licensee research revealed that NCR C-1034, dated July 19, 1978, had been prepared to document the concrete honeycomb areas involved in this allegation.
The Architect / Engineer's direction was to remove the honeycomb back to sound concrete. The void area was then to be filled with dry-pack concrete and/or small size coarse aggregate con-crete, all in accordance with a standard, engineer approved, repair procedure for such work. The RR1 observed various phases of the repair work from August 1978 through January 1979 when the repair was finally completed. None of the observations indicated a need for concern on the part of the RRI since the work was being done in a manner typical of acceptable methods of repairing such concrete structures.
Allegation 3: Mixup in Anchor Bolts The licensee's site QA Supervisor indicated a matter similar to this allegation had been the subject of a "possible" Significant Con-struction Deficiency Report to the NRC, Region IV office in 1977.
He offered a substantial file folder for the RRI's review. The file contained copies of Brown and Root Nonconformance Reports M-704 and M-722, dated July 18 and July 25, 1977, respectively.
The reports describe a mixup in a group of about 2000 bolts and nuts used.for embedded equipment anchorages which were supplied in part by Bostrom-Bergen Metal Products (Boston Made) and Southern Bolt Co.
(Southern Made).
It was not significant who supplied the nuts and bolts but rather that each supplier had been authorized to supply nuts and bolts of somewhat different steels in terms of chemical composition.
One composition was amenable to tack velding of the nut to the bolt prior to embedment in concrete while the other was not.
The NCRs describe a combined engineering and construction management solution to properly identify the differing materials and to utilize the materials which could not be readily welded in a different method of assembly.
The above matter was reported to the NRC and was followed to conclusion as indicated in Inspection-Report 50-445/77-09.
The RRI had no further questions relative to this allegation.
1
)
Allegation 4:
As indicated under paragraph 2, this allegation includes two separate items which will so be treated in 61s analysis.
Allegation 4.a: General T1oor Cracking During the past fifteen months, the RRI has toured all of the safety-related plant areas several times each month. The RRI has not observed cracks in the floors of the buildings that he would consider significant in terms of possible structural failure; i.e.,
cracks which are open to such an extent that awl or pick can be inserted to a substantial depth in the crack.
The RRI would expect fine hairline surface cracking to occur and normally not notice it.
Such hairline cracks are an unavoidable occurrence in heavily reinforced concrete structures, particularly in walls or floors with a relatively thick cross-section. According to recognized technical literature such as the U. S. Department of the Interior's " Concrete Manual," the cracking is caused by differing amounts of thermal expansion between the interior of the member and its exterior created by the chemical reaction process referred to as hydration and commonly called curing.
Such cracking is usually very tight and when investigated, extends only into the concrete to the most exterior layer of reinforcing steel, typically one to two inches below the surface. This type of cracking is not considered to have any effect on the integrity of the structure.
Allegation 4.b: Omitted Borizontal Ties in Containment 1 Walls The RRI has not been able to either effectively substantiate or to refute this allegation. (It is hypothesized that the alleger ab misconstrued an event which occurred in the Unit 2 Containment vall just before his_ final period of employment.
This event tf involved the initial omission of horizontal ties (more commonly referred to as shear ties) in the upper part of the Unit 2 Con-tainment wall and is discussed in Inspection Report No. 50-446/
.79-18.
This hypothesis is based on substantial indications that all of the allegations made were essentially based on hearsay information relative to events about which the alleger had little or no personal knowledge. -
- - -..- -.