ML19330B771
| ML19330B771 | |
| Person / Time | |
|---|---|
| Site: | Trojan File:Portland General Electric icon.png |
| Issue date: | 07/11/1980 |
| From: | Mccollom K, Mark Miller, Paxton H Atomic Safety and Licensing Board Panel |
| To: | |
| Shared Package | |
| ML19330B763 | List: |
| References | |
| ISSUANCES-SP, NUDOCS 8008050477 | |
| Download: ML19330B771 (80) | |
Text
e UNITED STATES OF AMERICA.
O, nuCttia REGutATORY ~COMM1SS10N
. E.. r. ~ J THE ATOMIC SAFETY AND LICENSING BOARD _
Marshall E. Miller, EsqdE2M,#-CNaihdag 03
~
Dr. Kenneth A. McCollom, Member Dr. Hugh C. Paxton, Memb,er;.m
)
In the Matter of
)
)
PORTLAND GENERAL ELECTRIC COMPANY, et al. )
Docket No.50-344SP
)
(Trojan Nuclear Plant)
)
July-11, 1980
)
INITIAL DECISION (Control Building Modifications)
/
Appearances Mcurice Axelrad, Esq. and Albert Carr, Esq.,
Lowenstein, Newman, Reis, Axelrad & Toll, 1025 Connecticut Avenue, N. W.,
Washington, D. C.
20036 Ronald W. Johnson, Esq., Portland General Electric Company, et al., 121 S. W. Salmon Street, Portland, Oregon 97204 For Portland General Electric Company, et al., Licensee William W. Kinsey, Esq., Bonneville Fever Administration, 1002 N. E. Holladay, Portland, Oregon 97205 Robert L. Jones, Esq., Bonneville Power Administration, Office of General Counsel - AP Post Office Box 3621, Portland, Oregon 97208 For Bonneville Power Administation, Intervenor Frank W. Ostrander, Jr., Esq. and Richard M.
Sandvik, Esq., Department of Justice, 500 Pacific Building, 520 S. W. Yamhill, Portland, Oregon 97204 For State of Oregon, Intervenor l8008050 "[7
r 2.
Nina Bell, 728 S. E. 27th Avenue, Portland, Oregon 97214 Eugene Rosolie, 215 S. E. 9th Avenue, Portland, Oregon 97214 For Consolidated Intervenors and Coalition for Safe Power, Intervenors Joseph R. Gray, Esq. and Henry McGurren, Esq.
Office of Executive Legal Director, U. S.
Nuclear Regulatory Commission, Washington, D. C.
20555 For U. S. Nuclear Regulatory Commission, Staff 6
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..e e
b TABLb 0F CONTENTS
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PAGE NO.
I.
PRELIMINARY STATEMENT 1
A.
ULTIMATE ISSUES 1
B.
PHASE II EVIDENTIARY HEARING 3
II.
FINDINGS OF FACT 8
A.
DESCRIPTION OF THE BUILDING COMPLEX 8
B.
DESIGN DEFICIENCIES AND OBJECTIVES OF MODIFICATIONS 10 1.
The Wall Problem 11 2.
Objectives of the Proposed Building Complex Modifications 12 C.
DESCRIPTION OF PROPOSED MODIFICATIONS 13 D.
STRUCTURAL AD5QUACY OF THE MODIFIED COMPLEX 16
.l.
Criteria for Determining Structural Adequacy 17
- a.. Determining-Structural Adequacy 18 b.
Seismic Input for the Analytical Model 18 2.
Determining Structural Adequacy of the Modified Building Complex 19 a.
The STARDYNE Analytical Model 20 b.
Sources of Nonlitiearity Accounted For 21
'c.
Load Determinations 23 24 d.
Capacities Determination e.
Comparison of Capacities to Loads 27 i
29 f.' Building Displacements g.
Influence of the Wall Problem on Structural Integrity 30 h.
Conclusions of Structural Adequacy 31
a
- - 11 PAGE NO.
3.
Seismic Qualifications of Equipment, Components and Piping 33 a.
Floor Response Spectra 33 b.
Qualifications of Safety-Related Equipment, Components and Piping 35 Influence of the Wall Problem on Equipment c.
Qualification 35 d.
Conclusions on Seismic Qualifications of Safety-Related Equipment 36 4.
Conclusions on Meeting the Criteria for Structural Adequacy of the Modified Building Complex 36 E.
MODIFICATION WORK AND EFFECTS ON SAFETY OF PLANT OPERATION 38 1.
Placement of Concrete Walls 38 2.
Ins'tallation.o,f. Steel Plates 39 3.
Welding Beam-Column Connections and Rebar 40 4.
Protection of Equipment During Modification 41 5.
Maintenance of Fire Protection During Modifica-tion 42 6.
Prevention of Interference with Operator Actions by Modification Work 44 7.
Seismic Qualification During Modification 44 F.
ADDITIONAL CHANGES RESULTING FROM THE MODIFICATIONS 45 1.
Relocation of Railroad Track from Control Build-in'g
' 45 2.
Reduction in Size of Existing Equipment Hatch 47 G.
RESOLUTION OF INTERVENORS ' CONTENTIONS 47 1
i
i s
iii PAGE N_O.
H.
LENGTH OF INTERIM OPERATION AND TIME FOR COMPLETION OF MODIFICATION 48 I.
ENVIRONMENTAL CONSIDERATIONS 49 J.
POSTHEARING AFFIDAVITS 50 1.
An Additional As-Built Wall Discrepancy 50 2.
Anchorage and Support of Electrical Equipment 53 III.
CONCLUSIONS OF LAW 54 IV.
ORDER 56 APPENDIX r
Y e
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UNITED S.TATES OF AMERICA NUCLEAR REGULATORY COMMISSIO,N BEFORE THE ATOMIC SAFETY AND LICENSING BOARD In the Matter of
)
)
PORTLAND GENERAL ELECTRIC COMPANY, et al. )
Docket No.50-344SP
)
(Trojan Nuclear Plant)
)
INITIAL DECISION (Control Building Modifications)
July 11, 1980 I.
PRELIMINARY STATEMENT
-r A.
ULTIMATE. ISSUES This Initial Decision concerns the ultimate issue of whether the scope and timeliness o~f' proposed modifications, required to bring the Trojan Nuclear Plant into substantial compliance with NRC Operating License No. NPF-1, are adequate from a safety stand-point.
This issue was defined in Section IV of the Commission's Order for Modification of License issued May 26, 1978 (43 Fed. Reg. 23678,-23770).
This ultimate issue of the adequacy of proposed modifica-tions from a safety standpoint, also involves the question of whether operation of the Trojan plant can be conducted safely i
while such modifications are being performed and prior to their completion.
Interim operation of this nuclear plant was authorized in Phase'I of this proceeding by our Partial Initial Decision issued i
d
-2 December 21, 1978 (LBP-78-40, 8 NRC'717).
Pursuant to that Partial Initial Decision, an amendment ge issued to the Trojan operating license authorizing -interim operat.on of the plant "until further order of the Atomic Safety Licensing Board issued in conjunc-u tion with the decision on the scope and timeliness of modifications from a safety standpoint..." (Id. at 747). - That "further order" is one of the subjects under consideration in this Phase II of the proceeding.
The background events of this proceeding were set forth in the Partial Initial Decision (8 NRC 717), and they will not be repeated in unnecessary detail here.
The May 26, 1978 Modification Order resulted from the discovery by the Licensee 1I and its agent, the Sechtel Corporation, of several design errors with respect to the shear walls.in the Control Building at the facility.
This Modification Order found that these design errors reduced the structural capacity of the Control Building, that the originally intended seismic capability and safety margins should be substan-tially restored by appropriate modifications, and that operation of the facility in its as-built condition would violate the facility license Technical Specification 5.7'.l.
However, the Modification Order further found that the Control Building had adequate structural capacity to safely withstand the licensed Safe Shutdown Earthquake 1/ ortland Genersl Electric Company (PGE), the City of Eugene, P
Oregon and Pacific Power and Light Company, the licensed owners of the plant referred to collectively as the " Licensee".
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(SSE)2/ Lfor the Trojan facility (0.25g peak horizontal ground acceleration).
~
The Modification Order also provided *. hat any person whose interests might be affected could file a request for hearing.
A number of persons availed themselves
,,f this opportunity for hearing and were admitted as intervening parties to the Phase I evidentiary hearings (8 NRC at 722-23).
The. Licensing Board also ordered the
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bifurcation of the proceeding into two phases (Order of August 25,
~1978).
Phase I involved a consideration of and decision upon the question of interim operation of the Trojan plant prior to modifi-cations of the Control Building, and culminated after evidentir y hearings in the Partial Initial Decision of December 21, 1978 (LBP-78-40, 8 NRC 717).
The instant Phase II of the proceeding involves consideration of the structural adequacy of the proposed modifications themselves and the safety aspects of their implementation.
B.
PHASE II EVIDENTIARY HEARING Written contentions were required to be filed by the inter-vening parties in Phase II of the proceeding, and contentions were filed by the Coalition for Safe Power (CFSP) by Eugene Rosolie and by the Consolidated Intervenors (CI, consisting of Nina Bell, David 2/That is, the facility design must be such as to insure that, should there be an earthquake providing the defined level of vibrating ground motion at the site, the structures, systems and components necessary to bring about a safe shutdown of the reactor will remain functional.
See 10 CFR Part 100, Appendix A, Section III(c).
- 3. -McCoy and C. Gail Parson).1I Following oral argument at a pre-
~
hearing conference on March 29, 1979, certain of the proffered' contentions of both -CFSP and CI were admitted as issues in contro-versy.
The a?-40ted contentions of CI were subsequently dismissed because of the failure of CI to comply with a Licensing Board Order compelling responses to discovery requests from the Staff.b/
At the Intervenor's request, CI was consolidated with CFSP, and CI was bound by the responses to interrogatories filed by CFSP.
The contentions which remained as issues are as follows:
CFSF No. 3 Plant Staff review of proposed modifica-tion is inadequate to assure no viola-tions of Technical Specifications will occur (Tr. 3011-20).
CFSF No. 4 NRC Staff review of proposed modification is inadequate to assure no violations of Technical Specifications will occur (Tr. 1046-51).
CTSP No. 12 Licensee has not provided information which shows that the plant can be operated during modification work without an undue risk to the public health and safety (Tr. 3055-59).
i CFSF No. 13 The plant cannot operate in a safe condi-tion while the modification work is being done (Combined with CFSP No.12, above.
Id.).
CFSF No. 15 Licensee has not identified all safety equipment or equipment.needed for safe operation of the plant that would be 1/ ntervenors Colu=hia Environmental Council (CEC) and Stephen M.
I Willinghat f ailed to file-contentions in Phase II, and accord-
-ingly they were dismissed as parties by the Prehearing Conference Order (Phase II) of April 12, 1979.
4/ ee. orders entered June 5 and June 15, 1979 and October 17, 1979.
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affected by proposed modifi' cations (Tr. 3062-63).
CFSF No. 16
, Licensee has not made adequate plans to protect all safety equipment and equip-ment for safe operation during the modification work (Id.).
CFSP No. 17 Performance of modification work' will hamper the ability of plant operators to respond to any emergency properly and thus poses an undue risk to the public health and safety (Tr. 3063-65).
CFSP No. 20 Inadequate asses'sment of the effects of drilling in the Control Building walls during modifications has been made (Tr. 3078-83).
CFSP No. 22
~The effect of the steel plate on dis-placement in the Complex has not been completely analyzed (Tr. 3094-98, 3108-11).
The Licensee filed a motion for summary disposition of CFSP Contentione 3, 17, 27 knd,22.
After hearing from all parties, the Board granted the motion for summary disposition as to CFSP 3 (Tr. 3485), but denied the motion with regard to CFSP 17 and 20 (Tr. 3498, 3513).
The Licensee withdrew its motion as to CFSP 22 (Tr. 3514), and CFSP voluntarily withdrew its Contention 4 (Tr.
3615).
Accordingly, the contentions considered at the Phase II evidentiary hearing were Nos. 12, 13, 15, 16, 17, 20 and 22, suora.
The_Intervenors also sought to raise an issue concerning the adequacy of the Licensee's existing-security plan to deal with the modification work.
At the Board's suggestion, all parties stipulated a procedure under which a Staff security expert would review.and evaluate the security plan in light of the Intervenor's
6, concerns over the modification work,.5/
Subsequently, CFSF requested this security review to include several incidents which had occurred the Trojan plant after the original review.5/
The security review at was performed as requested and the evaluation showed the security plan to be adequate while the modification work was being performed.
Although CFSP indicated that it felt that the Staff's review was not adequate, it gave no basis for this view when requested to do so by the Board.1/
No nexus was shown between the incidents alleged and the issues over which this Board has jurisdiction.
Such matters are therefore not relevant to this proceeding and cannot be considered here.8/
All parties prefiled their written testime,y according to the schedule set by the Board at the March 11, 1980 prehearing con-ference.
On March 17, 1980, Licensee prefiled the written testimony of Donald J. Broehl, Lief W. Erickson, Richard C. Anderson, William H. White and Kenneth M. Cooke on matters other than structural adequacy of the modified Complex (Licensee Exh. 27).
In addition, Licensee prefiled the written testimony of Richard C.
Anderson, Willian H. White, Bimal Sarkar and Patrick Chang-Lo on 1/ r. 3095-93.
T 5/ r. 3402-12, 3527-30, 3583-89.
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T 1/ r. 3529-30, 4682-83.
T 8/
- However, the Intervenors may request the Director of Nuclear Reactor Regulation to institute a show-cause proceeding if they have concerns about security at the Trojan facility.
10 CFR 2.202; Portland General Electric Company (Trojan Nuclear Plant, ALAB-534, 9 NRC 287, 290, n. 6 (1979).
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' - 7.
the - structural adequacy matters ' (Licensee. Exh. 28), as well as the Ltestinsny onTthese matters of Licensee's independent dxperts, Professors Myle J. Holleyp Jr. and Boris Bresler- (Licensee Exh. 29A).
The Staff prefiled the direct written testimony of
. Charles M. Trammell,'!!I, Fred Clemenson,-James E. Knight, Kenneth t
l S. Herring and-Drew Persinko on matters other than structural adequacy of the modified-Complex (Staff Exhs. 12, 14, 15 and 16).
On March 21, the-State of Oregon prefiled the testimony of Dr. Harold I. Laursen on'the structural adequacy of the modified Complex (Oregon Exh. 2).
On March 24, 1980, the Staff prefiled the testimony of-Kenneth S., Herring and Drew Persinko on structural adequacy j
catters (Staff Exh. 17).
Finally, Licensee prefiled its answers to questions previously propounded by Dr. McCollom (Tr. 3531-35),
on March 30 (Licensee Exh.. 30).
}
The Phase.II evidentiary hearing was held in Portland, Oregon on March 31-April 3 and April 16-17, 1980.
The only limited appearance' statement from a member of the public was heard on March 31 -(Tr. 3792-94).
Witnesses were presented at both sessions by Licensee, the State -of Oregon and the NRC Staff.
CFSP attended the hearing and cross-exanined witnesses, but presented no witnesses
+
of its own.
The Board conducted extensive examination on all of the direct evidence-presented.
When.the hearing began on March 31, the Staff's prefiled i
-testimony indicated that resolution had not yet been reached 1
- between the. Staff-.and the Licensee with respect to a number of the
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-8 natters that-had been described as unresolved in the Staff's Safety Evaluation Report '(SER) filed February 14, 1980 (Staff Exhs. 13A, 133).
With respect -to nonstructural matters, the Staff indicated that all matters were resolved by the close of the first hearing session (Tr. 4480 (Gray)).
The illness of the Staff's principal structural' witness (Tr. 4476-83) caused a delay in the resolution of structural matters.
However, the Staff subsequently filed revised testimony which reflected that these matters were resolved to the Staff's satisfaction (Staff Exhs. 15A, 17A).
Thus, there were no controversies between the Licensee and the Staff before the Board for resolution at the hearing.
The record compiled for Phase II comprises more than 1,000 pages of transcript as well as the exhibits which were admitted into evidence,,as listed in the Appendix attached hereto.
II.
FINDINGS OF FACT A.
DESCRIPTION OF THE BUILDING COMPLEX The Control, Auxiliary and Fuel Buildings (Building Complex) are interconnected by their foundation systems and floor slabs.
The Auxiliary Building is located between the Fuel Building at the east end of the. Building Complex and the Control Building at the west end and is supported laterally by both the Fuel and Control Buildings, with the reinforced concrete floor slabs acting as diaphragus to transfer lateral loads.
The connecting floor slabs
-9 and walls interact when subjected to seismic lorces (8'NRC 723-24; Licensee Exh. 24, pp. 1-12).
The Turbine Building, which is closely associated with the. proposed modification, is adj acent and west of the Control.3uilding.
The Con:rol'3uilding is a box-type structural system wirh its ground floor on rock foundation at elevation 45 feet, concrete floors ac elevations 61 feet, 77 feet, and 93 feet and with a roof slab at eleva ion 117 feet.
The Control Building is composed of a structural steel framing system with steel beams and columns supporting reinforced concrete floor slabs, with shear walls designed to resis: lat,eral seismic forces of an earthquake.
Most of the shear walls are of a composite-type construction (composite walls) consisting of a reinforced or unreinforced concrete core between two layers (wythes) of rein, forced grouted masonry block.
The two block wyrhes generally sandwich the structural steel frame so that 4
.the steel frame members are embedded in the concrete core (Licensee Exh. 24, pp. 3-12; Staff Exh. 13A, p. 1).
A railroad. bay is locate at ground level in the Control Building between column lines 41 and 46 with large openings in the east and west walls for train access.
Tne Auxiliary Building is approximately 115 feet by 62 feet with the longer dimension running in the East-West direction.
~At the. lower level, the north and south walls are composite walls and the other. walls. are of reinforced masonry block.
Above eleva-tion 61 feet, the exterior walls are reinforced masonry block and t
-w a
- 10 interior valls are reinforced masonry block or, for shield walls, co:posite walls.
The walls from elevation 93 feet to'll7 feet are reinforced masonry block (Licensee Exh. 24, pp. 3-13).
The Fuel Building is approximately 62 feet by 180 feet with the longer dimension running in the North-South direction.
Floor slabs at elevation 61 feet, 77 feet and 93 feet provide con-tinuity with the Auxiliary Building.
From 93 feet to the roof level at elevation 138 feet, the structural system is steel framing rather t.lan block and reinforced concrete walls.
Most of the lateral resistance of the Fuel Building is provided by the enclosure structure for*~ the holdup tanks and the spent fuel pool (Licensee Exh. 24, pp. 3-13).
B.
DESIGN DEFICIENCIES AND OBJECTIVES OF MODIFICATIONS The Control Building design deficiencie's that led to the Order for Modification of License of May 26, 1978 are:
(1)
Both the horizontal and vertical reinforcing steel embedded in the inner concrete core of the Control _ Building shear walls is generally discontinuous, in that it is not anchored to the steel beams and columns of the Control Building's steel frame as required by appli-cable codes and standards.
(2) -Misapplication of the applicable code ACI 318-63 shear design formulae in combination with.the applicable limiting OBE seismic
_ 11 _ '
loading resulted in less than the required acounts of reinforcing steel in the shear walls.'
As a result of these design deficiencies, the capacity of the Building Complex tog' ether with the contained systems and components to withstand seismic events is lower than intended (8 NRC 725-26; Staff Exh. 13A, p. 2, 510 ; Staff Exh. 17A, p. 3).
1.
The. Wall. Problem In late 1979 during a plant shutdown, the Licensee reported deficiencies in certain double-block walls (wall problem) in the Control Building Complex, which could influence structural integrity and support of piping in the event of an earthquake.
Because the wall problem introduced uncertainty in issues that led to interin operation, the Board issued an order requiring further information on the matter and specifying that permission of the Board would be required for resumed operation.EI The Board held a hearing on December 28 and 29,1979 for expeditious consideration of the matters in this order.
Testimony of witnesses at this hearing satisfied the Board that interim operation could safely continue when permitted by the Office of Inspection and Enforce-ment (Tr. 3443-46, 3449-50).
Although both Licensee and Staff viewed the wall problem as an independent enforcement matter, the Board did not agree and it asked to be kept informed of further developments.
S/ odification of Order Permitting Interim Operation of Trojan Nu-M clear Plant, November 30, 1979.
- 12 s
Subsequently a report by the Staff's caso~nry consul-tant questioned Licensee's assumed value of allowable. stress in mortar bonding the double wall, " collar joint stress" (Staff Exh.
19).
This led to Staff's requirements for short ta:na in situ tests regarding collar joint stresses and ill-defined long term tests.
At the prehearing conference of March 11, 1980, a staff witness testified that double-block walls enter STARDYNE analyses and explained the Staff's desire for a ", confirmatory" test progran (Tr. 3544, 3603-14).
As a result, the Board continued to view the wall problem as a potential issue and asked Licensee and Staff to provide evidence regarding it at the evidentiary hearing.
2.
Objectives of the Proposed Building Complex Modifica-tions Although the as-built complex was found to be capable
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of withstanding' the 0.25g acceleration of the SSE specified for Trojan Nuclear Plant, the design deficiencies both reduced the conservatism and design margins with respect to seismic capability below that intended for the life of the plant, and reduced the operating basis earthquake (OBE)1SI capability below that required by the operating license (Staff Exh. 13A, p. 2; Licensee Exh. 28, pp. 7, 7a).
The Licensee proposed modifications intended to add strength to the Control Building, to t'ie the Control Building 1S/That is, the facility must be designed so that, should there be an earthquake providing that defined level of vibratory ground motion at the site, the plant nonetheless could continue in normal o d
. safety (peration without undue risk to the public health an 10 CFR Part 100, Appendix A, 5111(c)).
The 0.15g value assigned to the OBE by the seismic criteria pertaining to the Trojan facility, is not in present dispute.
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together in a better way, and to minimize the impact of the modifi-cations on operation of the Trojan Nuclear Plant (Tr.'3705-07, 3764 (Anderson) ; Licensee Exh. 27, p.15).
The objective of the proposed modifications is to substantially restore the seismic margins and conservatisms intended in the original design.
Such are relied upon to account for uncertainties in analysis, design and construction as well as assuring that older plants, such as Trojan, do not need to be back-fitted to meet newly-generated seismic design requirements that may be more stringent than those usually required (Staff Exh.17A, p. 3).
C.
DESCRIPTION OF PROPOSED MODIFICATIONS The proposed modifications to the Control Building include four new structural elements:
three parallel walls running in the North-South direction and a steel plate added to the west wall.
The railroad bay through the Control Building will be closed off by two of these walls, and the third wall is an interior wall crossing the current railroad bay (Licensee Exh. 24, 551.2.6, 3.2.1; Licensee Exh. 28, p. 10; Staff Exh. 13A, p. 6, 520; Tr. 3703-05 (Anderson)).
The four new structural elements proposed are:
(1)
Adding an interior shear wall on column line N in the Control Building railroad bay structurally connected to shear walls at column lines 41 and
o o
- 14 46 and to the undersi'de'of the floor slab at elevation 65 feet (Licensee Exh. 24, p. 3-3; Licensee Exh. 27, pp. 8, 9).
(2)
Adding a shear wall on column line R in the Contro'l Building railroad bay structurally connected by bolts and grouted reinforcement steel to the existing north and west walls of
~
the Control Building (Licensee Exh. 24, pp.
3-2, 4-5; Licensee Exh. 27, pp. 9-10).
(3)
Adding a shear wall along column line N in the
' Control Building railroad bay structurally connected by high-strength bolts and grouted reinforcement steel to the existing N line wall above eUevation 65 feet and the walls at column lines 41 and 46 (Licensee Exh. 24, pp. 3-2, 4-8 ; Licensee Exit. 27, p. 11).
(4)
Adding a three-inch thick steel plate onto the outside face of the R line wall to further strengthen the west wall of the Control Building extending from column line 41 to beyond column line 46 and between elevations 59 feet 3 inches and 97 feet 3 inches with structural connections to the existing R line wall by the use'of high-strength steel through-bolts (Licensee Exh. 24, Fig. 3.1-2; Licensee Exh.
27, p. 10).
- 15 The addition of these four structural elements wi?.1 add strength directly to the areas of the Control Building where the inherent structural weaknesses were brought about primarily by the railroad bay openings.
In addition' to the four new structural elements, structural icprovements will be~made at several locations involving welding of beam-column connections and connecting of discontinuous rein-forcing steel.
The six, structural improvements proposed are:
(1)
Welding of existing bolted beam-colurn t
connections on the south side of column 446-N beneath elevation 77 feet.
(2)
Welding of existing bolted beam-colutn connections on the south side of colu=n
~
46-N beneath' elevation 93 feet.
(3)
Making the enisting horizontal reinfore-ing steel continuous at the following locations:
(a)
In the 41 line wall at column line Q between elevations 45 feet and 65
- feet, (b)
In the 46 line wall at coluna line N between elevations-45 feet and 61 feet, (c)
In the 55 line wall at colu=m line Q between elevations 45 feet and 61 feet, and
16 -
(d)
In the 55 line wall at column line N between elevations 45 feet and 61 feet.
Making the existing horizontal reinforcing steel continuous requires removal of existing block and parts of the concrete core in walls to expose the reinforcing steel (Licensee Exh. 27, pp.12,13).
Certain ancillary work. not a part of the structural enhancement of the Building Complex, will be performed in addition a
to the major structural work described.
These include:
modifica-tions to safety-related equipment, components, and piping necessary for their seismic qualifications to the new building response spectra, instal'lation of a new louvered section in the Turbine
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Building wall along column line 41, relocation of the existing Turbine Building roll-up door between column lines S' and T west to column line U to provide an air supply for the emergency diesel generators after closing off the railroad bay, alteration of the railroad spur outside of the Control Building, and installation of a new floor slab at elevation 54 feet 6 inches in the closed-off portion of the railroad bay to accommodate use of that area as office spacc (sLicensee Exh. 27, pp.13-14),
i D.
STRUCTURAL ADEQUACY OF THE MODIFIED CO.GLEX Among other things, the May 26, 1978 Order for Modifica-tion of License requires that the Control Building be brought into
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substantial cocpliance with Technical Specification 5.7.1, of the Trojan Operating License and to restore the intended design margins of that Technical Specifications such that:
(a) the Control Build-ing 03E capacity of 0.15g is met using 27. demping (FSAR Table 3.7.1) ;
(b) the Control 3uilding OBE capacity of 0.15g and SSE capability
, of 0.25g are met using a yield strength for reinforcing steel of 40,000 psi (FSAR 53.8.1.3.3); and (c) the masonry portions of the Control Building walls comply with Uniform Building Code (UBC) recuirements for reinforced grouted masonry (FSAR 53.8.1.4).
1.
Criteria for Determining Structural Adeauacy the criteria for determining structural adequacy of both the unmodified and modified Control Building are complicated by the fact that.the major shear walls of the Building Complex are generally composite walls'Yonsisting.of a reinforced concrete core placed between two layers of reinforced grouted masonry.
The provisions of the UBC applicable to casonry are not applicable to the combination of masonry and concrete making up the composite i
4 walls.
The UBC does provide for use of testing as an alternative
- to the code formulas. b 11/ or example, existing building codes do.not deal with the type F
of construction present in the Complex in which a steel frame is embedded in cocposite walls (Tr. 4420 (Bresler)).
Composite walls, as'used at Trojan are not addressed by the UBC (Licensee Exh. 28, p. 28; Licensee Exh. 30; Staff Exh. 17A, pp. 41-42).
Consequentiv,-the requirement in FSAR 53.8.1.5 that " concrete block walls be designed to UBC requirements for masonry cannot be met for the composite walls of the Complex for which there is no applicable code provisions (Licensee Exh. 29, p. 48).
- Instead, in-the absence of specific code provisions for composite walls, a test program was utilized.to provide the information and capa-city criteria that building codes would have provided (Licensee
'Exh~-28, p. 25; Licensee Exh. 29A,.pp. 5-6).
a a.
Determining Structural Adequacy The appropriate criteria by which it can be determined whether the requirements of the May.26, 1978 r der for r
Modification of License are met include:
(1) the specifications listed therein are us'ed in che analytical model; (2) it is demon-strated that the modifications would bring substantial compliance with the seistic design requirements of the Trojan FSAR as refer-enced by Technical Specifications 5.7~.1; and (3) where substantial literal ' compliance with those requirements is not possible due to the type of building construction, then conservative engineering judgments using alternative equivalent methodology are used.
The capacities of the new reinforced concrete walls and the new steel plate to be added are determined by two codes not referenced in FSAR-53.8, AC1 318-77 Code and AISC Manual of Steel. Construction, 7th Edition, respectively.
Their use is
~
consistent with that section's requirements regarding these materials (Licensee Exh. 28, p. 47 ; Staff Exh.13A, p. 69, 55.2.1; Tr. 4405 (White)).
b.
Seismic Input for the Analytical Model The seismic input criteria for use with the analytical model were provided for in the FSAR 53.7, and all such specificarions were used accordingly except for the derivation of the floor response spectra.
A new artificial time history with different frequency intervals from that specified in the FSAR was developed, which better characterizes the motion described by the
(
ground response spectra.
The new frsquency intervals selected for
-the ground response spectra :are in accordance with current practices as' set forth11n Regulatory Guide 1.122.
-A reassuring result is that the new floor response spectra enclose the one used'for the original seiscie design of the Building Complex.
2.
Determing Structural Adequacy of the Modified
' Building Complex The modified Building Complex was modeled and analyzed, with the three dimensional finite ' element STARDYNE computer program used for evaluation of the current unmodified Building Complex for interim operation (Partial Initial Decision, 8 NRC 717, pp. 730-33).
This model' generates loads, displacements and floor response spectra using the specified seismic input discussed above (Licensee Exh.-28, p.'36).
The determination of the structural strengths (capaci-ties) of the composite walls unique to the Control Luilding was derived from test results, with proper application to -the individual wall panels 'in the modified Building Complex ptovided as an alternative in'the UBC.
The various potential effects on the 4.-
collection of ~ wall panels of having the steel frame embedded in the cocposite walls vere also assessed and. accounted for in the analytical codel.
Similarly, the added walls and steel plates were
. analyzed to. assure that the appropriate amounts of shear wall-capa-cities would be realized.
1
~
+
~
a.
'The STARDYNE Analvtical Model The analytical codel was based on actual knowledge of the -distribution of mass' within the BuildinF_ Complex, and the require:ents.of TSAR 53.7 with respect to lumping masses were com-plied with (Licensee Exh. 28, pp. 37, 40; Staff Exh.13A, p.12, 53.2.1.2.2).
The stiffness of the structural elements in the model
.was based on caterial properties of those elements (Licensee Exh. 24, App. B, pp. 3-5. to B-5-c).
~
4 The analytical model assumes linear elastic behaOior and does not directly model potential nonlinear behavior.
Honlinear beh#vior, in turn, could result in a reduction of stiff-ness of _ the structural elements, a change in its natural frequency,
{-
and a potential' for change in the seismic loads imposed on the
.i i
structure as a whole (Liceis'ee Exh. 28, p. 22; Licensee Exh. 29A, pp. 13-14). - JL reduction in stiffness will also res 'l t in an increase in displacement.
The change in building frequency affects floor-respcase spectra and may' therefor affect seis ic qualifica-
-tions of~ecuipment, components and piping (Licensee Exh. 28, pp.
c I
29-30).
The potential nonlinear behavior was evaluated using'the STARDYNE analytical model through' additional iterative g
analyses.and postprocessing of the results predicted by the linear elastic model (Licensee Exh. 28, p. 39; Tr. 4422-23(3resler)).
- Thus, the effeers of-nonlinearities and stiffness degradation were accounted ifer with' appropriate. broadening of the floor response spectra
- (Licensee.Exh. 25, pp. 38-39,172 ;.Tr. 4385-86 (White)).
Included a
21 _
v in :the analysis.wereithe effects of' cyclic loading from earthquakes and resulting cyclic degradation'previously verified-in the wall t es t' progra= 1(Staff ' Exh. 13A, pp. 15-16, 5 3. 2.1. 2.18).,
The result-
.ing seistic analysis was performed in accordance with the applicable
' FSAR criteria on seismic system analysis (Staff Exh. 13A, pp. 10-15).
' t b.
Sources of Nonlinearity Accounted For The sources of nonlinear behavior considered by the' Licensee included cracking that develops in the concrete of the wall panels- (Licensee' Exh. 28, pp. 33-34) and potential lack of 4
connectis-ity between wall panels which are partially separated by
~ enbedded steel' columns (Licensee Exh. 28, p. 34).
The nonlinear behavior of the cracking in the concrete. wall panel was accounted for through the use of _ stiffness reduction factois derived from the results.of the Licensee's test
- program-(Licensee'Exh. 28, pp. 35, 38, 40 and 44; Licensee Exh. 24, App. B, pp. B-5-c B-5-di Staff Exh. 13A, p. 62, 5 5.1).
Because d
. the stiffness reduction is a function of shear and nornal stresses, e
iterative STARDYNE enalyses were performed to evaluate the appro-c priate reduced stiffness properties (Staff Exh. 13A, p. 63, 55.1.1;
- Licensee Exh. 28, pp. 38, 44).
~
The potential lack.of connectivity_between wall panels'resulted.in further investigation of'three related variables
- the amount;ot vertical reinforcement from the bean-column connec-tions of Jthe steel: framing system.used in determining stif fness in k
4, n.,
[r
' - 22 the - model,: the normal ~ stress parameter in' determining stiffness, and the > overall bending parallel' to,the component - of' the earthquake being considered ' tending to change stiffnesses 'at each end of the wall.
The. Licensee initirlly used the embedded steel-frame as vertical reinforcement in the analytical model-(Licensee Exh. 28, pp.c40-41).
To remove the concern of the effect of this potential nonlinearity, the License ~e submitted an evaluation indicating the impact of neglecting the contribution of the beam-4.
colu=n connections to stiffness with appropriate consideration for j
the result (Staff Exh.
a
.p.
63-64, 55.1.1.1; Licensee Exh. 25U-Licensee Exh. 28, pp. 67-69; Licensee Exh. 33).
The-Licensee concluded-that the normal stress-parameter contributing te call stiffness consisted of the dead load
~
of the portions of the wall above the elevation under consideration (Licensee Exh. 28_, pp. 41-42).
The potential effects for reducing this dead load considered were the effects of creep 'and shrinkage, 4
stiffening of beams.'due to encasement in concrete and the effect of
~
ochanges' in nean wall temperatures for exterior walls.
The potential effect for~ increasing theidead load considered was the vertical growth in.the wall" panels :in an earthquake due to the development of; flexural-cracking.
The' vertical growth was found to more than cc pensate.for-the potential reduction factors even when panels were-i subjected to stress. cycles (Licensee Ex'r. 25Q, Attch. 4; Licensee Exh. 23U; Licensee Exh. 28, pp. 43, -70; Licensee Exh. 32; Licensee
- Exh.'33).
I'
Seismic loads create a nonlinear " gross bending effect" which tends to increase ccepressive load on one end of a t
wall which is parall'el to the component of the earthquake and to decrease che available nornal stress on the other end of that wall.
This, in turn, results in an increase and decrease in wall stiffness in the local. wall areas (Licensee Exh. 28, p. 43; Licensee Exh. 29A, pp. 13-15 ; S:aff Ezh.13A, pp. 66, 68, 55.1.1.3).
Although the STA33YNI analysis did not account for this gross bending behavior, evaluations by the Licensee assured that overall stiffness would not change substantially (Licensee Exh. 28, p. 43; Licensee Exh. 29A, pp.13-15 ; Licensee Exh. 25Q, Attch.1,2 and 9 ; Licensee Exh.
32; Staff Exh.17A, pp. 29-30).
c.
Load Determinations
'TheSTARDINElinear_elasticanalysispredictedthe magnitude of the seismic loads to be resisted by the modified Building Complex and predicted the distribution of such loads among the carious structural elements of the modified Building Complex (Licensee Ixh. 24, pp. 3-11, 5 3. 3.1).
Fostprocessing of results, iterati.e calculational cycles, and supplemental analyses performed,
as described above,.have accounted for the effects on predicted loads of the influence of stiffness reduction.
The relative load distributions among the major shear wa'_is will not be changed by the stiffness reduction from dead lead reduction and neglecting the beam-column connections
'(Licensee Ixh. 25, pp. 31, 45).
Reductions in stiffness due to
O 4
gross bending effect will be offset by an associated change in shear capacity to satisfactorily account for potential' shifting of load from panels on the tension side of a wall to panels on the co=pression side (Licensee Exh. 25Q, Attch. 1; Licensee Exh. 28,
- p. 70).
An overall reduction in the stiffness of the modified 3uilding Complex due to potential nonlinear behavior would not result in a significant increase ~in the total inertia forces to be resisted by' the structure, since the natural frequency of the modified complex approximates the frequency which corresponds to the peak of the ground response spectra (Licensee Exh. 28, pp. 30, 38-39, 45-46; Tr. 4424-25 (Holley)).
d.
Capacities Determination
~
-The composite wall capacities were determined by the Licensee by use of testing as provided in UBC 5106 and 5107 (Licensee Exh. 28, p. 48; Licensee Exh. 29A, pp. 5-6; Licensee Exh.
30; Staff Exh. 17A, pp. 41, 42; Tr. 4420 (Bresler)).
The Licensee derived capacity criteria from the results of a test program using 23 ' test specitens which sinulated the parameters of the existing walls of the Suilding Complex (Licensee Exh. 24, App. A., pp. ' A-1 to A-5).
The caterials of construction, th'e aspect ratio and the thickness cf test specimens were sicilar to those of the actual walls infthe'Euilding Complex (Licensee Exh. 30; Staff Exh. 17A, p. 45).
i
~
-b
g d
The test program was adequate"to provide valid information on the behavior of composite walls and allow the deriva-tion and verification of capacity criteria (Licensee Exh. 28, pp. 25-26 ; Tr. 4468 (Laursen) ; Licensee Exh. 29A, p. 8 ; Tr. 4431, 4444 (Bresler) ; Tr. 4431-32.(Holley)).
The behavioral. characteristics of the test speci-mens were used to develop a theoretical double curvature shear capa-city. of individual wall panels as a function of the percentage of vertical reinforcing steel and the vertical or dead load acting on the wall.
Capacities derived by application of this equation ignored the bond betwe,en the steel columns and the composite walls (Licensee Exh. 2 8, p. 49).
This reflects at least the same level of conserva-tism as code Equations (Tr. 4431 (Bresler)).
.To arrive et capacity values, the Licensee calcu-laced the double curvature capacities of the individual wall panels for a given wall using the theoretical flexural equation.
Each individual wall panel's diagonal tension capacity was also computed based on the lower bound diagonal tension capacities derived from the test results.
The lower of the panel's double curvature and diagonal tension capacities multiplied by an appropriate capacity reduction factor, was then considered to be.the ultimate seismic capacity of the panel.
.The ultimate seismic capacity of an entire wall was then'obtained by summation of the capacities of individual panels (Licensee Exh. 24, pp. 3-18-b to e, 53.9.2.2, Table 3.5-1
_and 2, Figs. 3.5-6 to 11; Oregon Exh. 2, p.
7: Tr. 4445 (Holley),
4445-56 (3resler), 4468 (Laursen)).
-After later evaluations'were requested by the
' Staff, further capacity calculations were made such that the' capacity projected for a giveh wall be selected as the lowest capacf.ty for any of four potential modes including single curvature flexural and sliding _ failure in addition to the double curvature flexural and diagonal tension failure capacities.
Potential dead load reductions were also considered in the determination of-the walls sliding and i
the single and_ double curvature capacities (Staff Exh. 13A, pp.
71-74, 5 5. 2. 2.'l).
Licensee satisfied the Staff's concerns in these (Licensee Exh. 25U, Attch. 1; Licensee Exh. 28, pp. 53, areas 55, 77, 79; L4censee Exh. 30; Licensee Exh. 32; Licensee Exh. 33; Staff Exh. 17A, p. 31)'.
In all determinations of capacities, the design st.rength of the. reinforcing' steel and the design strength of con-crete were used even though tests have shown that actual strengths are larger than the design strengths (Licensee Exh. 24, pp. 3-18-e, 3-23, 3-27, 553.4.2.2, 3.6.1.2, 3.6.2; Licensee Exh. 28, p. 46).
The transfer of shear forces from existing struc-tural elements to-the new ones will utilize a post tensioned bolt system to clamp the new and the old together and roughening of the adj acent surfaces to assure adequate functi'onal resistance.
The resultingl combination should assure the full capacities of the new walls (Licensee.Exh. 28, p. 47; Licensee Exh. 33; Staff Exh. 13A, pp. 69-70, 55.2.1; Tr. 4365 (White), 4519-21 (Broehl)).
. s e.
Comoarison of Capacities to Loads The capacity of the modified Building Complex to resist both the SSE knd the OBE must be establf shed.
Since the OBE e
governs the design of the Building Complex and satisfaction of the 03E design criteria w~ould also constitute satisfaction of the SSE design criteria, the controlling load combination and acceptance criterion is that of the OBE (Licensee Exh. 24, pp. 2-1, 3-20, 552.1, 3.5; Staff Exh. 13A, pp. 17-18, 5 3. 2. 2.1.3).
This criterion requires that there exist a margin of 40% between the calculated loads and the corresponding ultimate capacities of the modified Building Compl'ex (Licensee Exh. 28, p.
58; Tr. 4423-24 (Holley)).
Capacity to force comparisons show that all but two of the minor shear walls in the modified Building Complex had a margin of at le a's t 40% between ultimate capacity and unfactored OBE loads (Licensee Exh. 24, pp.3-21).
Each of these two minor shear walls contributes a very small percentage of the total shear cepacity of the Building Complex.
Loads predicted but not carried by these two walls were readily shown to redistribute to the adjacent maj or shear walls -(Licensee - Exh. 28, p. 39; Licensee Exh. 30).
Moreover, no substantial deterioration of these walls would be expected from an SSE-(Oregon Exh.
2, pp. 7-8; Licensee Exh. 28, p.
25; Licensee -Exh. 30; Tr. 4362-63 (White)), and no equipment would be i pacted by any wall degradation that might potentially take place-(Staff'Exh. 13A, p. 83, 55.12).
l
The Staff requested further evaluations of seismic capability assuming further. conservatisms of wall capability, i.e.,
single curvature and sliding capacity failures, neglecting contri-butions of beam-column connections in determinstion of stiffness, the gross bending effect on stiffness and load distributions, and reduced coefficient of friction for the bolted connections for the R-line end N'-line walls.
Since most of these might-have their impacts on the seismic capabilities of the added shear walls on
~
K-line, K' line and R-line, the added conservative analysis does reassure that the intended capability does exist (Tr. 3532, 4369-70 (Chang-Lol ; Licensee Exh. 28, pp. 59-60; Licensee Exh. 25U, Attch.
1, 4; Licensee Exh. 25Q, Attch.1; Licensee Exh. 32; Licensee Exh.
33 ; Staff Exh.17A, pp. 27, 38-40).
The evidence shows that the potential effects of these uncertainties in behiv'ior and in the application of test results to predict behavior and capacities have been properly accounted for by these additional analyses and evaluations performed by the Licensee (Staff Exh.17A, pp. 35, 39-40).
The results show that capacity to force ratios for some individual wall panels for the unfactored OBE may fall below 1.4 for the worst possible com-binations of dead load reduction, gross bending and single and double curvature behavior.
However, redistribution of forces in the wall will occur so that the capacity to force ratio for the atire we.11 vill not be less than 1.4.
Thus the walls will caintain substantial margins in capacity even when uncertainties in structural behavior and application of test results are accounted
a
~
for by, analyzing the worst possible combinations of loading and 1
structural behavior (Staff Exh. 17A, app. 39-40).
f.
Buiiding' Displacements Consideration of building displacements is neces-sary to verify that (1) adequate clearance. exists.between adjacent structures so that any displacements induced by an earthquake (interstructure displacements) will not result in contact of, and physical' damage to the' adjacent structures and (2) neither relative displacements.between stories of a ' building (interstory displacement) nor1interstructure displacements will adversely affect equipment that is attached to more than one story or which runs between buildings.
The displacements for the modified Building Complex 2
.. ~.
we're determined'as1part of the' output of the STARDYNE analysis used to. determine. structural adequacy (Licensee Exh. 28, p. 60).
The STARDYNE analysis provided elastically calculated displacements which accounted for the nonlinearities due to the material charac-teristics of-the walls.
Supplemental calculations were performed to-account for the additional nonlinearities considered under
~
structural adequacy evaluations discussed previously.
These addi-tional nonlinearities would result in calcu' lated displacements increased by'a' factor of.2.1 over that calculated initially for the modified Building Complex'(Licensee Exh. 28, p. 80; Licensee Exh.
25U;. Staff Exh.17A, p. 32).
4 I
.\\
_j
o 30 -
The structures adjacent, but not conne'cted to, the Building Cocplex are the Containnent and the Tarbine Builtings.
The difference betwe,en the available clearance and the sum of calculated displacements multiplied by 2.1 for the Building complex-Containment Building interface is quite large and do not present any potential for impacts during an SSE (Licensee Exh. 25H).
The.available clearance at the interface between the Centrol and Turbine Buildings in -the modified Building Complex will be reduced at elevations 69 fect and 93 feet by the addition of the steel plate to the west wall of the Control Building (Licensee Exh. 25E).
By removal of a part of a concrete floor slab at elevation 69 feet and of part of the flange of a steel girder at elevation 93 feet in the Turbine Building, the resulting clearances beyween the Buildings-at tl.7eselevelsarerespectivelyat least 2.5 inches and 2.0 inches (Staff Exh.17A, p. 52; Licensee Exh. 28, pp. 61-63).
Even after including the added factor of 2.1, there is ample clearance since maxinus reduction in gap is 0.29 inches and 1.10 inches, respectively, at the 69 feet and 93 feet levels between the Centrol 'and Turbine Buildings (Licensee Exh. 28, pp. 61-63).
g.
Influence of the. Wall Problem on Structural Integrity Evidence concerning the wall problem included results t
s of the short tern test program.
Collar-j oint shear stresses for standard weight double-block walls were within the range assumed by Licensee, but for heavyweight block walls they were less than r
w-g
- m
g 31 -
l j
( f i
s expected though still greater than the postulated! allowable value.
Licensees' witnesses explained that there are no heavyweight double-block walls in the Control Building that are relied on in the STARDYNE model and that the heavyweight block walls in the Building Complex as a whole contribute less than 2.5% to the total shear resistance of the Building' Complex (Tr. 4893-94, 4729).
This effect on structural integrity is therefore considered negligible, but there remains the matter of adequately supported safety-related piping, -discussed cost.
h.
Conclusions of Structural Adeouacy The Board concludes that a thorough and extensive analysis has been made.of the modified Building Complex and the effects undergone in the event of an SSE or OBE.
Specifically, the Bcard finds:
(1)
That an appropriate seismic input criterion is used in the analytical codel; (2)
That the STARDYNE analytical nodel, augmentel to include the effects of nonlinearities and repetitive earth-quake events was an appropriate and acceptable model; s
'(3)
That appropriate seismic analyses were performed resulting in a conservative f
assessment of the behavior of the modified complex subjected to OBE and i
SSE events;
1 1
.-32-'
(4)
That the tei sm'ic loads for the modified Building Complex have been adequ'ately
- determined taking into consideration the appropriate pctential nonlinear behaviors; (5)
That the capacities of the walls of the modified Building Complex were properly deterdined through appro-priately derived characteristics based on test results and through proper consideration of potential behavior unique to the wall construction; (6)
That the assessment of the capacity to foce ratios for individual walls r
and wall panels was appropriate to ceet the criteria previously stated (SII-D, suora);-
(7) _That the relative displacements between the Building Complex and adj acent structures have been pro-perly assessed and that the avail-able clearances are sufficient to preclude building contact in the event of an OBE or SSE; and L
33 -
(8)
That the effect of the "W'all Problem" on structur'al integrity of the Build-
.ing Complex is negligible.
3.
Seismic Qualifications of Equipment, Components and Pioing To satisfy the criteria for determining the adequacy of the modifications, the safety-related1 / equipment, components and piping in the modified Building Cgmplex must be seismically qualified to withstand the OBE and SSE and. continue to operate satisfactorily.
The method of seismic qualification to the original ground level response spectra at elevation 45 feet which was specified in FSAR 553.7, 3.9 and 3.10 was also used to determine the seismic qualifications of equipment, components and piping for the codified Building Complex (Licensee Exh. 24, App. B, p. B-1, 51.2; Licensee Exh. 28, p. 64).
a.
Floor Response Spectra The SSE floor response spectra for these floors in the as-built Building Complex above ground level were redeveloped during Phase I of these proceedings to account for changes in the Building Complex response due to the design deficiencies.
They must again be redeveloped due to the proposed modifications.
Although SSI"Safetv-related" refers to equipment, components and piping to be seiscically cualified as identified in 10 CFR Part 50, Appen-dix B and furth5r identified in Regulatory Guide 1.26, Revision 3,rr.d 1. 29, Revision 3 (Licensee Exh. 28, p. 64; Licensee Exh.
24, p. B-1).
thel0EE' response. spectra were not addressed in Phase I of these proceedings, they must now be_ developed to account for changes in
~
Euilding1Co: plex response due to both the design deficiencies'and the proposed nodifications.
The 'new OBE and SSE floor response spectra have I
been_ generated using the artificial. time history and frequency inter-h vals previously described' (SII-D-1-b,. supra) and the STARDYNE model
^
(Licensee Exh. 24, App. B., ' pp. B-2,,B-3, f S 2. 2.1.1, 2. 2.1. 2).
The I
resulting response spectra. curves were then broadened to account for variations in cass and for variations in stiffness due to variations in the codulus of elasticity and in the stiffness reduc-tion factors due to de.ad load, shear. stress and experimental uncertainties. -The response spectra curves were also broadened on the icw frequency side of the response spectra to ' account for potential reduction in stiffness due to the postulated occurrence of multiple earthquakes, the potential dead load reductions, exclusions of the bear-colurn connections from vertical reinforcement ratios,
the pctential influence of gross bending and potential vertical slip along the e bedded columns (Licensee Exh. 24, App. B,_pp. B-5-e, B-5-f,
!2.2.1.4; Staff.Exh. 17A, p. 34).
These effects accumula-tively. result'in a total broadening of 41% on the low side and'10%
on the high-side of the peaks of the response spectra associated with the s ructural frequencies (Licensee Exh. 25U; Licensee Exh.
-28, p. 31).
i n~
.,_u-,,
-,-~l
E b.
Qualifications of Safety-Related Equipment, Components and Pining Licensee has made a commitment to evaluate the seistic-qualification of all safety-related equipment, components x
and piping 'in the Building Complex using the revised response spectra developed-above.. Modifications will be implemented to assure quali-fications based on these evaluations (Licensee ~ Exh. 24, pp. 4-4, 4-8, 5-1, !f4.2.1, 4.2.5, 5.2; Licensee Exh. 24, App. B, 551, 3-6;
~
Licensee Exh. 25G; Licensee Exh. 27, p. 13,; Licensee Exh. 28, pp.64-65a).
c.
Influence of the Wall Problem on Equipment Qualification Much of the safety-related equipment that had been supported by double-block walls, generally piping required for shutdcwn in the' event of di earthquake, has either been through-bolted or Eanchored elsewhere (Tr. 4698).
But the disputed value of acceptable collar-joint shear strength of the heavyweight block walls casts uncertainty on seismic qualification of equipment that is still supported there.
Consequently, Licensee agreed to resolve remaining-ni~sgivings of the Staff before operation is resumed af ter the current shutdown for-refueling, and proposed modifications to accceplish this (Tr. 4695-97, 4699, 4742-44).
Staff's witnesses
-testified that the parties were converging on an acceptable analytic procedure, that the Licensee's proposed method of strengthening double-block _ walls seemed appropriate, and that long term tests related to collar-joint shear stress may be unnecessary (Tr. 4546-47, I
W
'O:
b-
~
4792-93).
Licensee ~has agreed to confirmatory testing of support anchors in double-block walls, although loads have been reduced
-(Tr. 4701-02, 4743-45).
In view of the Licensee's agreenent to resolve remaining double-block wall issues before resuming operation, and the negligible influence of these walls on structural adequacy, the Board is persuaded-that the wall problem has been explored adequately.
d.
Conclusions on Seismic Qualifications of Safety-Related Eauiument The Board finds that the implementation of'modifi-cations deternined by application of the revised response spectra to a'_1 safety-related equipment, components and piping in the Building Complex will bring compliance with FSAR requirements and Technical Specif,ications 5.7.1.
4.
Conclusions on Meeting the Criteria for Structural Adecuacy of the Modified Building Complex The evidence 'shows that the evaluations of the proposed modifications of the Building Complex and the safety-related equip-ment contained therein have been made appropriately to assure, upon completion of implementation of the resulting modification, that the criteria established previously (SII-D-1, suora) will be satisfied.
This conclusion was supported by three technical experts testifying'at the hearing who did not participate in the detailed design ofLthe proposed modifications.
Professors Myle J. Holley and '3cris 3resler found the analysis and criteria for the structural y
1
design and evaluation to be both rea,sonable and appropriate, and that the criteria had been applied properly to the walls of the 3uilding Complex.
They concluded that the modification design, in their judgment, would bring the Control Building into substantial compliance with _the originally intended design (Licensee Exh. 29A,
- p. 17; Tr. 4422-23, 4445-46 (Bresler and Holley)).
Professor Earold Laursen concluded that the proposed modifications would restore the major shear walls to necessary margins of capacity (Oregon Exh. 2, pp. 7-9; Tr. 4469-70 (Lauzsen)).
In addition, the Staff testified that the Licensee has properly accounted for the limitations in STARDYNE and for uncertainties in structural behavior and in applying the test pro-gra= results with the results that the proposed modifications will substantially restore the seismic margins and bring the Control Building into substantial ompliance with the requirements of the Troj an License (Staff Exh. 17A, pp. 39, 54-55).
Based on the uncontroverted evidence in this hearing, the Board finds that the proposed modifications satisfy the required criteria stated earlier and that they are adequate from a safety standpoint.
Upon satisfying that implementation of the modifications can be accomplished in a safe manner, the proposed nodifications to the Control Building should be implemented.
E.
MODIFICATION WORK AND EFFECTS ON SAFETY OF PLANT O?ERATION With the exception of installation of massive plate 8, the plant is. expected to be in operation during the Control Building codification work.
The possible influence on safe operation was exa=ined in detail and protective measures were devised where appro-priate.
Obj ectives were to protect safety-related equipment from techanical dacage and deleterious eff_ects of dust and vibration, to prevent interf.erence with operation by noi.se or Control Room traffic, and to caintain seismic qualification of equipment and effective energency procedures including access for fire protection and for safe shutdown 'in the event of an earthquake.
Maj or activities, placement of new concrete walls,
installation of steel. plates on the west wall of the Control Build-ing, and exposure and joining of steel columns and beams, are described below and protective measures are specified.
1.
Placement of Concrete Walls The concrete walls to close the former railroad bay of the Centrol-Building and to provide internal structure are poured as an early stage of modification.
Footings for these walls must be placed around piping and a cable duct bank that are below grade.
For protection, the duct will be covered with compressible backfill and the pipe will be enclosed in sleeves (Licensee Exh. 27, pp.
15-19;.Tr. 3772-76).
Forms for the concrete imply the temporary presence of combustible caterial that will be taken into considera-tion for~ fire protection.
The forms for the east wall will frame T
e.
~
battery racc. ducts such that ventilation will be caintained J(Licensee E>th. 27, p. 40).
Otherwise, no safety-relat'ed equipment will be disturbed.
Steel plates 1 to 3, positioned as discussed below, will corstitute part of the form for. the west wall (Licensee Exh.
27, pp. 47-43).
The new walls will bei joined to the existing structure by teans of bolts and grouted rebar (Licensee Exh. 27,
~
pp. S-13).
2.
Installation of Steel Plates Frelicinaries to plate installation include the follow-ing :
Concrere floor s. labs and steel girder flanges of the Turbine Building will be trinmed to provide space for the plates and to raintain clearance to the Control Building with the plates in place
- (fr. 3 758, 45C6-07).
Holes for bolts to secure the plates, drilled through the west wall of the Control Building, will be positioned to aecid reinforcing steel.
Finally, the hole pattern will be' transferred rc the plates and matching bolt holes drilled in the shop.
Zight three-inch thick steel plates are sequentially brough" into place through the Turbine Building, raised to the turbina floor (II. 94 feet), jockeyed into position, and lowered into_ place against.the west wall of the Control Euilding.
They are secured by bolts through the wall (into the wall for plate 7) and
.'cined by welding to fora a single reinforcing plate (Licensee I
4-,
40 -
s Exh. 27; Tr. 3962-68).
Equipment to be protected during this process consists of-four groups of cable trays that pass underneath from the Control Building to the Turbine Building, and the duct bank'and piping below ground level.
For the first seven plates, ranging in weight from 2,700 to 24,000 pounds, cargins of safety on handling equipment will be at least a factor of five, and the effect of' accidental dropping along the west wall will be limited by energy-absorbing material.
With an additional license requirement for installation of plate 7 (Staff Exh.13A, p. 90), the Staff agrees that these plates cay be installed while the plant is operating (Tr. 4666-67).
Seismic effects added to a drop of plate 8, however,
. introduce uncertainty in safe plant shutdown if required during handling of that 47,000-pound plate.
For this reason, the plant
- will be shut down while plate 8 is being moved into position and secured to the. west wall (Staff Exh.15A, pp. 19-24).
Special protection includes an A-frame support to prevent the plate from falling if the crane support should fail while the plate is being coved into position (Tr. 3976), cribbing on the floor, cribbing to prevent an accidental drop of more than two inches while the plate is lowered into position, and energy-absorbing material to mitigate the effect of a two-inch drop (I.icensee Exh. 27, p. 54, Tr. 3922-23).
3.
Welding Beam-Column Connpctions and Rebar The six " structural improvements", welding beam-column conn'ections in two locations and Cadwelding rebar in four locations, L
require ' exposure of the steel by removal of concrete and block' To the.extenripracticable, this will be done outside the Control Build-ing or in -the forcer railroad bay.
Nevertheless, there are locations where. cables in tray 5 may be subject to damage from dislodged frag-ments or dropped tools unless protected (Licensee Exh. 27, pp. 24-27).
Eecause simultaneous exposure in all six locations could reduce seismic resistance unacceptably, the Licensee proposes two alternative work sequences in which structural capacity is restored in each of five phases before proceeding to the next phase (Tr. 3708-12).
Evidence demonstrates that either sequence will maintain adequate resistance to the 0.25g SSE (Tr. 3906, 4463-65, 4620, 4658).
4.
Protection of Eauipment Durine Modification Safety-related., equipment within modification work areas consists primarily of cables in trays.
During trimming of Turbine Building floors and steel flanges, drilling holes for bolts that suppcrt sreel plates, installation of bolts and washers, and exposing steel for welding, nearby cables will be protteted from dropped fragments, components or tools.
This will be accomplished by steel covers for cable trays and by scaffolds under massive pieces such as steel wahhere while being positior.ed (Licensee Exh.
27, pp. 24-30).
Temporary openings through which tornado-driven missiles tight enter will be closed by shields satisfying FSAR criteria (Licensee Exh. 27, pp. 27-28; Staff Exh. 15A, pp. 31-32).
Equipment to be protected from dust generation during
~
the above operations extends to electrical relays in the Control Room and equipment in the Switchgear Room.
Methods of protection will include water sprays on drills and collectors, temporary enclosures about work areas, and, if necessary, fans and ducts (Licensee Exh. 27, pp. 31 and 38: Tr. 3786-88).
Because of seismic qualification, vibration is not expected to influence safety-relate'd ' equipment.
5.
Maintenance of Fire Protection During Modification The modification work can complicate fire protection follow [ng ways :
There will be additional conbustible in the caterial such as forms for new concrete walls, temporary enclosures for dust control, and scaffolds and wooden cribbing to linit acciden-tal dropping of steel plates and washers.
Splatter from welding or slag frot flate cutting could ignite combustibles.
Sone fire barriers will be penetrated by bolt holes or openings to expose steel.
Finally, access paths for fire-fighting could be blocted by the extra workers and equipment that will be required.
Whenever nood is in the neighborhood of safety-related equiptent, fire extinguishers will be nearby and the area will be inspected at least hourly by a fire patrol (Licensee Exh. 27, pp.
35-36; Staff Exh. 13A, pp. 26-27; Staff Exh. 14, pp. 22-23).
Where possible, wood will be removed beforehand from any area where there is to be welding or cutting (Tr. 3932).
s A special permit is required for welding or flame cutting.
This permit provides for a fire watch near the work that must remain at least-30 minutes af ter completion.
It also requires protection of equipment and cables, which will be accomplished by either fireproof blankets or protective barriers between the work and equipment (Licensee Exh. 27, pp. 31-32; Tr. 3753, 3783-84 and 3889-90; Staff Exh.13A, pp. 24-25 ; Staff Exh. 14, pp. 18-21).
Ehere fire barriers are breached by bolt holes, as in east and west walls of the Control Buildidg, the holes will be plugged temporarily until bolts are installed.
(This will also maintain Contnol Room ventilation.)
Where there are lacger open-ings, as for exposure of columns for welding, there will be either a continuous fire watch, or a temporary fire barrier, fire detector, and a fire watch patrol (Licensee Exh. 27, pp. 32-33; Staff Exh. 13A, pp. 59-60).
There will not be a large number of workers who might interfere with access for fire or other energency, sixteen for
.installaticn of plate 8 and no more than eight for other tasks (Licensee Exh. 27, p. 78).
Training of workers and supervisors will provide -for evacuarion to the Visitors Infor ation Center in the event of an energency'(Licen.cee Exh. 27, pp. 76-77).
Two access routes are available to any area with equipment for emergency cperation and one always will be-unobstructed by modification work (Licensee Exh. 27, p. 75; Staff Exh. 13A, pp. 28-29; Staff Exh. 14, pp. 23-7).
The' Staff has' determined, and.the. Board agrees, that Licensee has appropriate administrative means to satisfy Technical Specifications, primarily fire protection and Control Room ventila-
'tien rectirements, during modification (Staff Exh.13A, p. 60).
6.
Prevention of Interference With Operator Actions By Modification Work In addition to potential interference with emergency action, su; discussed above, operators could be disturbed by workers
~
in the Centrol Room, or noise or dust from modification work.
There will be some drilling and bolting through Control Rocu walls, but at a distance from' controls and instrumentation.
Although drill'ing will be from outside the walls, workers who w*ll collect water for dust control and debris will be on the inside 4
(Licensee Exh. 27, pp. 31 and 38).
The shift supervisor will prevent j
interference with operation by workers or excessive noise, and the NRC's Resident Inspector also may halt work, if necessary, until tools or cethods are changed to reduce noise (Licensee Exh. 27, p.
81; Staff Exh. 13A, pp. 49-50; Staff Exh. 14, pp. 36-38).
7.
Seismic Qualification During Modification The only modification work (including bolt hole effect) that.could reduce seismic resistance of the Building Complex signi-ficantly would be the removal of concrete for exposing steel to be welded (Licensee Exh. 27, pp. 60-72).
With the exception of a colurn at the new interior wall, these codifications will be per-forced after the Control Building is strengthened by new walls and 2
e
steel plate (Licensee Exh. 24, p. 4-6-a).
Either alternative sequence proposed by the Licensee for steel exposure and replacement of concrete will maintain seismic capability of the Building Complex (Licensee Exh. 27, pp. 69-71; Staff Exh. 15A, pp. 27-29; Oregon Exh.
2, pp. '9-10; Cregon Exh. 2A; Tr. 3708-10, 3903-06, 4341, 4461-66, 4619-21).
Temporary effects of modification work'on the seismic qualification of equipeent are forestalled by the described measures
~
to protect equiprent and by plant shutdown during installation of plate 8 because of uncertain seismic effects (Staff Exh. 15A, pp.
19-24; Tr. 4019, 4113).
At Intervenors' suggestion, both trains of equipment for maintaining cold shutdown will be operable during installation of plate 8 (Tr. 4102, 4305-07).
F.
ADDITIONAL CHANGES M SULTING FROM THE MODIFICATIONS In addition to the modifications discussed above, there will be other changes in existing features of the Building Complex:
the changes brought about by closing off the railroad track through the Control Building and the reduction in size of the equipment-hatch into the Electrical Auxiliaries Room of the Control Building at elevation 65 feet.
^
1.
Relocation of Railroad Track From Control Building Currently, the air intake path to the Emergency Diesel
. Generators relies en an opening to the outside through the railroad hay in the Control Building.
Before the Control Building railroad 4
hay is scaled off at column line R, an alternate air intake system i
4
~
will be provided in the north wall of the Turbine Building railroad bay.
The design of the alternate air intake was found'to be adequate-(S aff Exh.-13A, pp. 40-41; Staff Exh. 14, p. 58, Licensee Exh. 2', ' p. 5-5 ; Licens ee Exh. 251, Fig. 15-1).
A new ra'lroad spur to the Fuel Building is required i
as an alternate _to the path being closed through the Control Build-ing. 'The railroad spur was initially designed through the_ Control Building as a matter of con /enience and efficiency to serve both the Turbine Building and the Fuel Building' (Staff Exh.16, p. 5).
Since there is no need for loading or unloadind' railroad cars in
~
the Control-Euilding bay, there is no safety-related impact of removing it and providing a spur to the Fuel Building (Staff Exh.
16, p. 5).
Since the railibad track in the Turbine Building will be terminated at the face of the new shear wall at the west face of the Control Building, a bunping post will be installed that is only d= signed to prevent a typical train loa'd'ing frcm impacting the west wall uhen the train is traveling at very low speeds (Staff Exh.
16, p.
6; Staff Exh. 13A, pp. 77-78; Staff Exh. 17A, p. 50).
How-ever, the Licensee has in place administrative procedures to control the novenent of-trains on site (Staff Exh. 16, p. 6).
Also, the accidental ap roach of a train to the railroad bay from the main track is prevenred by-twc derailers located both outside and inside the security' fence andLan uphill grade of the track outside the securi:y_ fence (Staff Exh. 16, pp. 6-7).
1
~,
The Board finds that the proposed. modifications to the railroad spur and the proposed administrative controls on operation of trains by Licensee personnel when inside the security area are acceptable.
2.
Reduction in Size of Existing Eauipment Hatch The existing equipment hatch into the Electrical Auxil-iaries Roon of the Control Building at elevation 65 feet on the etst wall approximately midway between column lines 41 and 46 will be reduced in. size from 8 feet high by 7 feet wide to 4 feet high by 4 feet wide.
The large hatch currently allows larger ?quipment to be brought into and removed from this elevation without need for dis a s s enbly.
After the reduction in size, disassembly of some e cipment will be required in order to fit the smaller equipment hatch, or use of an alternative path such as the Control Building elevatororAuxiliaryBuilhingaccessways (Staff Exh. 16, pp. 2-3).
No safety 1 significance for this addit'ional disassembly has been iden:ified.
The Board finds that neither the performance of the nadification work on the equipment hatch nor the reduction in size cf the' hatch has safety significance and this modification is acceptable.
C.
RESOLUTION'0F INTERVENDRS' CONTENTIONS The Contentions in issue in this proceeding are CFSP Con-ten:icnsL 12, 13, 15, 16, 17, 20 and 22.13/
Our findings of fact z.
se*See i
-3_,
suora.
~
above have encompassed all substantive matters raised by these con-tentions and, based on our review of the entire record, we find that-the original' concerns of the Intervenors that brought the contentions into-issue have now been cddressed in a satisfactory canner, leaving all of the contentions upon completion of the evidentiary. hearing without merit.
All of the contentions are covered in our findings under SII-E, supra,-entitled Modification Work'and Effects on Safety pf Plant Operation.
H.-
LENGTH OF INTERIM OPERATION AND TIME FOR COMPLETION OF MODIFICATION Based on-the evidentiary record in the Phase I hearings on interim operation, the Board found that the existing Building Complex had adequate seiscic capacity to safely withstand a 0.25g SSE '(8 NRC 735).
In the event of one or core seismic events of 4
0.08g or larger,' the Troj an Nuclear Plant must be brought -to a cold shutdown - condition and be inspected to determine the effects,
if any, of the' earthquake.
Operation cannot resume under these 4
circumstances without prior NRC. approval (8 NRC 748).
Nevertheless, si.nce there may be some effect in the event of seismic events above i
0.08g, because there may be some time dependence of the seismic capability, and since the May 26, 1978 Order instructed an expeditious. implementation of modifications, it seems appropriate to impose.a time restrictica on completion (Staff Exh. 17A, pp.
9-11).
1 1
l
The evidence shows that it,will take approxima'tely 10 months to complete the codifications as currently proposed.
The Staff has reviewed,the modification work schedule, has concluded that it is reasonable, and has reccomended that a license condition be Lcpos'ed requiring completion of the proposed modification work within a period of 12 months from the date of authorization (subj ect to extension for circumstances beyond Licensee's control)
(Licensee Exh. 27, pp. 86-87; Staff Exh. 13A, p. 88; Tr. 4018-19 (Trm=rell)).
The Board finds that such a condition provides appro-priate assurance that the modification program will be completed expeditiously (Licensee Exh. 24, Fig. 4-1; Staff Exh.13A, p. 88) and that the' design intended margins will be restored in a timely fashion.
I.
ENVIROWENTAL CONSIDERATIONS i
i.'hile no issue was raised in this proceeding as to the environcental impacts of the proposed modifications and the attend-ant' licensing action authorizing them, an environmental analysis was performed by the Staff.
That analysis demonstrates that the proposed modifications will not result in significant environmental inpacts and that the impacts, if any, will be negligible (Staff Exh. 13A, pp. 92-94, 58. 0).
Based on the analysis, the Staff concluded that the proposed modifications do not require the preparation of an Environmental Impact Statement or Environmental Impact Appraisal.and Negative Declaration pursuant to 10 CFR
.Pcrt 51.
i
The evidence presented in this regard'was uncontroverted.
We find that the Staff's conclusions as to the environmental icpacts of the proposed modifications are adequately supported by the environmental analysis presented, and that those conclusions are justified.
J.
?CSTEIARING AFFIDAVITS 1.
An Additional As-Built Wall Discrepancy Cn May 19, 1980, after the record was closed in this EcarinE, the Licensee informed Mr. R. H."tngelken, Director, U. S.
Nuclear Zegulatery Commission, Region V, about conditions found in the south yall of.the Auxiliary Building adjacent to column line 55 between column lines F and N from Elevation 61 feet to Eleva: ion 93 feet which was not connected to the floor slab at Elevarion 93 feet as assuqed.
The wall was assumed to be connected and participate as a minor structural shear-resisting element in the STARDYNE finite element analyses of the Building Complex.
The wall also provides partial lateral restraint for cable trays vertically supported from structural steel beneath the Elevation 93 feet floor slab.
The discovery of this condition was reported in greater detail in a " Reportable Occurrence" in Licensee Event Report 80-07 in a letter to Mr. Engelken from Donald J. Eroehl of Portland General Electric dated May 30, 1980.
Also, in a letter from Licensee to Mr. Robert A. Clark, Chief, Operating Reactors Branch No. 3, Division of Licensing, dated June 4,1980, justifying
51 -
change of Trojan Nuclear Plant operation fron. modes 6 to 5 in ' pre-paration for a return to power after refueling, further inspection had identified no additional walls that were not connected at the top, although 1 other walls were identified as not yet meeting the criteria docu=ented in Supplement 3 to LER-79-15.
The Board was concerned about some of the implications of these reports and the conditions described therein, particularly reg."rding the Auxiliary Building wal1 which is not adequately connected at its top to idarfacing structural elements.
In the study of the structural adequacy of the Building Complex and in the nodifications proposed to correct these conditions, the Board relied on the analyses using the STARDYNE computer program.
In the codel, all walls were assumed to be in a state of construction which we now find for this, wall did not exist.
This concern was reflected in an " Order Requesting Licensee to Supply Information by Affidavit" issued by the Board on June 2, 1980, in which the Board requested the Licensee to supply the following infor=ation:
(a) The cause of the occurrence, (b) When all other walls with similar potential defects will have been exacined to determine if there are other such problets, (c) Report of cethod and timeliness of corrections to the current identified defects and any cthers discovered, and
1
- 52 -
[
)
~
(d) Contribution to structural ade'quacj of'the 1
3uilding Complex for any other walls found with this deficiency.
The Licensee responded to the order in a letter transmitted to L5e Board dared June 16,.1980, with affidavits containing the requested infermation.
In addition to the original discrepancy described above, the field exaninations by Licensee identified five walls having nonconforcances of potential safety significance, three in the Fuel 3uilding and two in the Auxiliary Building.
Three of the five non-confortances.,related to incomplete construction, two involving incomplete grouting from the top of the masonry unit to the floor slab and r.he third an approved Field Change Request that was not implemenred.
A fourth nonconformance related to an interference between reinforcing dowels from the slab above and a steel beam supporting the floor.
The fifth nonconformance was at a nontypical interface on a minor shear wall where the assumed design interface conditions were not implemented.
The Licensee stated that all of the abcve-described correc:ive actions (the fifth nonconformance was determined not necessary to.ina corrected) were. to be completed by June 18, 1980, and in any event prior to the resumption of power cperations at Trojan Nuclear Plant.
Following completion of corrective actions,
theJonly reduction in capacity is claimed to be 1.'% in the North-Sou:h direction.
j i
The Board finds this an acceptable resolution of the nonconformances discovered in connection with LER-80-07.
2.
Anchoraze and Suonort of Electrical Eauipment In another co=nunication dated June 12, 1980, and sub-sequent to the closing of _he evidentiary record in this proceeding, the Staff brought to the Board's attention IE Information Notice 80-21 concerning potential deficiencies in anchorage and support of safety-related electrical equipment at some older plants.
Although the Staff indicated that problems addressed by this Information Notice were not directly related to the Control Building design deficiencies or proposed structural codifications, it requestad that Licensee provide a written response to the Notice.
The response by the Licensee, in the form of a letter aind affidavit dated June 27. 1980, described inspections showing that no significant deficiencies brought out by the Notice exist at _ the Troj an Plant.
Nevertheless, the a~fidavit promised a further inspection program to confirm the conclusion that all safety-related electrical ecuipment is properly supported and anchored, end made a commitment to satisfy the Staff in this regard.
The Board concludes that IE Information Notice 80-21 and Licensee's response introduce no new safety consideration appro-priate to this' proceeding, and that the Staff and the Licensee have concluded arrangements adequate to handle such matters administra-tively.
54 III.
CONCLUSIONS OF LAW This proceeding concerns the issue of whether the scope and ti=elir.ess~of proposed modifientions, required to bring the plant into substantial compliance with Operation License No. NPF-1, are adecua:e from a safe'ty standpoint.
We have reviewed all of the evidence subcitted by the parties relating to this issue.
We have also considered all of the proposed findings of fact and conclusions of law submitted by the parties.
Those proposed findings not adopted in' this Initial Decision are herdby rejected:
Based upon our consideration and evaluation of the entire record, we conclude that:
1.
The proposed modifications of the Building Complex should be permitted in accordance with the amend-ments to the Operating License set forth in the Order below and subject to the terms and conditions therein; 2.
There is reasonable assurance that operation of the plant, including the activities authorized by the operating license, as thus amended, and including the terns and conditions set forth in the t
Order below, can be conducted without endangering the health and safety of the public; 3.
There is-reasonable assurcnce that operation of the plan:, including _the activities authorized by the-operating license, as thus amended, and including v
y rr-n,
the terns and conditions set forth in the Order below, will be conducted' in compliance with the Commiasion's regulations; 4.
The issuance of this operating license snendment as set forth in the Order below will not be inimical to the cocmon defense and security or to che health and safety of the public; 5.
The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regula-tions and all applicable requirements have been satisfied; and 6.
The proposed modifications will satisfy the Order of May 26, 1978 by bringing the Control Building into substantial compliance with Technical Specifi-cation 5.7.1 of the operating license, and restering the intended design nargins of Technical Specifict.-
tion 5.7.1 such that (a) the Control Building has a capacity to withstand a 0.15g OBE using 2% damping as required by FSAR Table 3.7.1; (b) the Control Building OBE capability of 0.15g and SSE capability of 0.25g are met using a yield strength for reinforcing steel of 40,000 psi; and (c) the masonry portions of the Control Building walls comply with the UBC requirements for reinforced.
. grouted r.asonry for inplane ^_cading.
Ii
)
IV.
ORDER Wherefore, it is ORDERED, in accordance with the Atomic Energy Act of 1934, as srended, and the regulations of the Nuclear Regula-tory Cornission, and based on the findings and conclusions set forth above that the Director of Nuclear Reactor Regulation is authorized to cake appropriate findings consistent.with this Initial Decision in accordance with the Commission's regulations,
and to issue the appropriate license amendment to Facility Opera-ting License No. N?F-1 authorizing impleSentation of modifications to the Control Euilding of the Trojan Nuclear Plant.
This license amendment shgil contain the following provisions and conditions:
A.
Upon the effective date of this Atondment to Facility Operating License No. NPF-1, said License is modified as follows:
1.
The'following"[rovisionshallbeaddedto Facility Operating License NPF-1:
2.C.11 Control Building Modifications.
The Licensee is aurhorized to and shall proceed with modi-fications to the Control Building in order to restore substantially the originally ~ intended design cargins.
The modification program sha'_1 he accomplished in accordance with PGE-1020, " Report on Design Modifications for the Troj an Control Building", as revised through Revision No. 4, and as supple ented by PGE Exh._27 (Licensees Testimony ("Broehl, et al.")
J
<xt Matters Other Than Structural Adequacy of the Modified Complex, March 17, 1980). 'Any deviations or changes from the foregoing documents shall be accomplished in accordance with the provisions of 10 CFR part 50.59.
The Control Building modification program shall further be subject to the following:
(a) The modification program shall be completed not later than 12 months,from the date of this amendment, provided however that such completion date may be extended by the Direct.r of Nuclear Reactor Regulation upon a showing that the completion of the modi-fication program is necessarily delayed by circumstances wholly beyond the control of Licensee.
When all modifications have been conpleted, license condition 2.C. (10),
relating to interim operation pending completion of modifications, is cancelled.
(b)' For the installation of steel plate No. 8, the plant shall be in the cold shutdown condition (Modes 5 or 6) from the time that s
L the plate'is lifted from the transporter at Elevation 45-feet until the plate has been il secured with 48. inches of weld to the 4
e i
- - 58:-
a e
previously.installe'd plates and attached to the.vall with 'five bolts made snug'.
During the' installation of plate No.
8, both
' trains of safety-related equipment necessary
.for caintenance of a cold shutdown condition shall-be operable.
Prior to the installa-tion, Diesel Generator A shall be started and proper operability verified.
('c)- Solid steel cable tray covers shall be
, installed over cable trays in work areas where cable damage is possible from accid' ental dropping of steel plate washers during their installation.
(d)-A fire waf'h patrol shall be established
~
c whose sole responsibility shall be to watch for fires at the plant and which shall make at -least hourly inspections at all safety-related areas where combustible materials (e.g., wood framing, planking, I
plastic,. etc.) related to the modification work must remain in the work' area-(not s-required for areas.in which a continuous fire watch is present).
Such hourly
. inspections shall include-direct visual 5 "
w
a observations of all.combustibie materials added to'such safety-related areas.
(e) Scaffolding and timber planking shall be installed against the R line wall in the Cable Spreading Room during the installa-tion of the steel plate washers at each location where a potential plate washer drop onto a cable tray could exceed three feet.
The planking shalf-be placed and constructed to limit the maximum height of a dropped washer to three feet or less.
(f) Any construction work in the diesel generator conbustion/ ventilation air
, pathway which could potentially generate dust, dirt or debris shall be temporarily
- ,alted when any diesel generator is in operation.
(g) In the event that either the Shift Super-
. visor or NRC Resident Inspector determines that construction noise is resulting in noise leve'ls in the Control Room of such i
magnitude as to interfere with norcal cocaunications, the construction activity shall be halted until alternate means are devised (e.g., lighter weight tools, other
-1
O 60 neans of concrete / block removal, etc.) to proceed with the work with acceptably reduced Control Room noise level.
(h) In he event that the NRC Resident Inspector determines that the construction activity in the Electrical Auxiliaries Room o'r Control Room is generating excessive dust, dirt or debris or the use of water is beingimproperlycontrol{ed, construction work shall be halted until appropriate corrective measures have been taken.
(i) During periods when safety-related equip-cent is vulnerable to either external missiles or missiles from construction work (e.g., j ackhammers), Licensee shall provide suitable barriers to protect against such exposure or place the plant in cold shutdown during such work.
(j) During hole drilling in the east and west valls of the Control building, personnel shall be stationed on the opposite sid:
of the wall from the driller ~to monitor s
the drill penetration.
Continuous voice communications shall be maintained between the drill operator and the monitor.
-e
. (k) Fire blankets (Claremont Weld Shield 800-24 or Fabricote 1584-white) shall be used over all-cables in' areas where Cadwelding, welding or cutting will be performed.
(1) The -Battery Room exhaust duct shall not be disabled unless an alternate, equivalent means of Battery Room ventilation is'first provided.
~
(m) Prior to the installation of plates 1 through 6, a temporary energy absorber shall be installed to preclude exceeding the a$11owable compressive strength of the underlying concrete in the event of an
. accidental' plate drop.
(n) An energy absorber shall be placed on plate 4 prior to the installation of plate 7.
(o) A ene-ir.ch-thich, precrnshed, stabilized' Hexcel pad and timber cribbing shall be used on top of the previously installed 1
plates for' energy absorpri;n during the i
installation of plate 8.
(p) The wor'.e. area' at 41 R (Elevation 65 feet) shall be protected by a dust-tight flame-retardant enclosure.
Similar protective
measures shall be applied at any other
, locations in the Electrical Auxiliaries Room or Control Rnom where wall removal is necessary.
(q) Piping systems, equipment and components within the Control / Auxiliary / Fuel Building Cocplex required for safe shutdown or to maintain off-site dohes from accidents to within 10 CFR Part 100 guideline values shall recain seismically qualified for darthquakes up to end including the SSE throughout all structural modification work.
Any changes to piping systems,
, equipment _,and components necessary to ensure that this condition is met shall be performed before the structural modifi-cations are made.
(r) The Licensee shall perform three grout tests for each size and orientation of reinforcing steel (rebar) to be grouted into the existing walls.and hole size (considering both depth and radius) in s
which they are to be. grouted prior to proceeding with construction (grouting of rebar), orothe Licensee shall perform three grout tests using the maximum 1bar E
size in the'ninimum diameter hole size.and ethedment length for each orientation (i.e., horizontal, vertically up and down).
These tests shall be designed to demonstrate that the yield strength of the rebar can be developed by the grout.
If any test result is unsuccessful, the NRC shall ba notified.
(s) Should a drop of plates 7 or 8 occur onto the plates below, the Ligensee shall report the circumstances to NRC immediately.
Plates 1 through 6 shall be removed and dmnage inspection cade unless it can be substantiated to the satisfaction of the NRC Staff that plate removal is unnecessary.
~
(t)' Exposure Af embedded steel columns in the Control Building walls during the codifi-cation work shall be subject to the following restrictions:
(1)
Between Elevation 45 feet and Eleva-tion 65 feet, colurn.41 Q may not be exposed unless colu=ns 41 R and 41 N are ecbedded in the original wall or s
encased in concrete that has attained a cocpressive strength of 2,000 psi; likewise columns'41 R and 41 N cay
e:
not be exposed unless column 41 Q is embedded or encased by 2,000 psi'
- concrete.
(2)
Columns 55 N' and 55 Q may not be exposed concurrently, and the second of theso may not be exposed before the concrete encasing the first'has attained a etepressive strength of 2,000 psi.
-(3)
No colunns may be exposed above Elevation 65 feet before concrete in the new N' wall has attained a corpressive strength of 3,500 psi and the new concrete in the N and R walls below Elevation 65 feet has
-attained a compressive strength of 2,000 psi.
(4)
Between Elevation 65 feet and Eleva-tien 77 feet, columns 41 N and 46 N cay not be exposed unless ' columns 41 R and 46 R are ecbedded in the original wa'_1 or encased in concrete that has s
attained a compressive strength of 2,000 psi; likewise coluans 41 R and 46 R may not be exposed unless columns e
o.
41 N and 46 N are embedddd in the original wall or encased in 2,000
. psi concrete.
(5)
Above Elevation 77 feet, column 41 R R
may not be exposed unless the new concrete in R line wall below that elevation has attained 2,000 psi compressive strength, and columns a
41 N and 46 N are edbedded in the original wall and/or encased in 2,000 psi concrete.
(u) Prior to the installation of plate 7, the concrete behind plates 1-4 shall have
, attained a compressive strength of 3,500 psi.
Prior to the installation of plate 8,
'the concrete behind plates 1-7 shall have attained a compressive strength of 3,500 psi.
(v)' In any plane of a wall at any given ~ floor elevation, the wall crea removed from drilling pursuant to the proposed codifi-cations, including holes abandoned because rebar was encountered and net filled with grout that has reached design strength, shall be licited to 67..
i.-.
2.
The following amendments shall be.cade to the Technical Specifications in Appendix A to Facility Operating License NPF-1:
(a) Section 5.7 of Appendix A shall be amended in accordance with Attachment 21-1 of Licensee Exh. 33.
(b) A Technical Specification and Bases for the Control Building codification connec-tion bolts shall be added conforcing to At ta c*.: ment 6-1 of Licensee,Exh. 33.
It is fuyther ORDERED, in accordance with 10 CFR 5f2.760, 2.762, 2.764, 2.785 and 2.786, that this Initial Decision shall be effective iacediately 4 / and shall constitute the final action 1
of the Commission forty #ive (45) days after the issuance thereof, subject to any review pursuant to the above-cited Rules of Practice.
Exceptions to this Initial Decision may be filed within ten (10) days af ter service lof this Initial Decision.
A brief in support of the exceptions shall be - fil'd within thirty (30) days thercafter (forty (40) days in the case of the NRC Staff).
Within thirty (30) days of the filing and service of the brief and service of the brief of the Appellant - (forty (40) days in the s
b/This proceeding is not covered by the Conr.ission's recent suspen-sion of the irrediate effective. ness rule (10 CFR 52.764) for certain purposes.
44 Fed. Reg. 65049 (Nove ber 9, 1979).
e
67 -
case cf the NRC Staff), any other party cay file a brief in sup-g/
port of, or in opposition
.o, the exceptions.
.I.f.
It is so ORDERED.
THE ATOMIC SAFETY AND LICENSI::G 50ARD L$
../W Dr. Kenneth A. McC511on, Me:Soer gM
!=-
Dr'.
Hu@ C. 'Paxton, Member A.4 c-$) h 0-a fiarsh'all E. Miller', ' Chairman Dated.at Bethesda, Maryland this lith day of July 1980..,
s
- m. -.. _.-
6 O
PPENDIX' List of Exhibits,Adritted in Evidence Admitted Into No.
Licensee Exhibirs Identified Evidence 24 "Report on Design Modifications 3668 3676 for the Trojan Control Building" (PGE-1020), as revised through Revision 4.
25A Licensee's Letter to the NRC enclosing 3668 3676 additional information provided by
'Bechtel relating to the propose.d modificaticas or the Trojan Control Building (shear wall specimen testing progran and lateral stiffness and resocnse spectra determination)
(February 28, 1979).
253 Licensee's letter to the NRC 3668 3676 providing clarification to letter of February 23,.1979 - (March 2, 1979).
25C Licensea's letter to the NRC with 3668 3676 responses prepared by Bechtel to the
-NRC Staff. technical questions of March 8, 1979 (March 28, 1979).
25D Licensee's letter to the NRC with 3668 3676 responses prepared by Bechtel to 20 of the 50 cuestions of May 18, 1979 (June 22, 197 9).
25E Licensee's letter to the NRC with 3668 3676 responses' prepared by Bechtel to 14 of the 50 cuestions of May 18, 1979 (June 29, 1979).
25F
.Licensce's letter to the NRC with 3668 3676
-resconses orerared by Bechtel to NRC que'stions 'at' sed dur'ing the June 13-14, r
1979 visit to the Troj an Nuclear Plant (July 5,.197 9).
25G Licensee's letter to the NRC with 3668 3676 resconses'orecared.bv Ber...tel concern-ing'nos: c'd t!.e outs'tanding-questions of May
'3, 1979 (July 6, 1979).
h m
2-e Adcitted Into No.
Licensee Ef.* bits Identified Evidence 25H Licensee's letter to the RRC with 3668 3676 responses prepared by Bechtel concern-ing nost of the outstanding questions of May 18, 1979 (July 6, 1979).
25I Licensee's letter to the NRC with 3668 3676 respenses prepared by Bechtel to NRC questions of July 20, 1979 (August 13, 1979).
25J Licensee's letter to the NRC with 3668 3676 esponses prepared by Bechtel to NRC questions of August 17, 1979 (September 5, 1979).
25K Licensee's letter to the NRC confirming 3668 3676 discussions concerning timing and content.,of PGE-1020 revisions (September 26, 1979).
25L Licensee's letter to the NRC with 3668 3676 responses prepared by Bechtel to several of the NRC Staff questions of Sectember 14, September 28 and Oc'ober 2, 1979 (No' vim'ber 21, 1979).
t 25M Licensee's letter to the NRC with 3668 3676 responses prepared by Bechtel to several of the NRC Staff questions of Sep ember 14, S'eptember 20, September 28 and October 2, 1979 (December 17, 1979).
25N Licensee's letter to the NRC with 3668 3676 responses prepared by Bechtel to several of the NRC Staff questions of September 14, Septe ber 20, October 2, and October 18, 1979 (December 21, 1979).
250 Licensee's letter to the NRC weih 3668 3676 resp:nses prepsred by Bechtel to the retaining ::RC 5taff cuestions' of Septe ber 14, Septecher 20, and October 2, 1979 (Dece=bcr 22, 1979).
i Admitted Into No.
Licensee Exhibits Identified Evidence-25?
Licensee's letter.co-the.NRC with 3668 3676' supplemental material' prepared by Sechtel relating to the proposed.
modifications to.the Trojan Control Building in response to NRC Staff questions of-May 18, October 2, September 20 and September 14, 1979, respectively (January 28, 1980).
25Q Licensee's letter to the NRC with 3668 3676
=2terial prepared by Bechtel respond-ing to requests from NRC Staff in telephone conversations during the week of-January 28, 1980 including corrected Page 3 of Attachment 5
. (February '13,.1980).
25R Licensee"s letter to the NRC with 3668 3676 material referenced in Licensee's response ~to NRC Question 6 of Septecher 20, 1979, University of Missouri Test Report (February 21, 1980).
25S Licensee's letter to the NRC with 3668 3676 Bechtel Drawings RSK-1,
-2,
-3, -4 (March 5, 1980).
25T.
' Licensee's letter to the NRC with 3668 3676 information on compressive strength of masonry assemblies (f 'm) March 6, 1980).-
25U Licensee's. letter to the NRC with 3668 3676 responses prepared.by Bechtel to the NRC. Staff's request for-supplemental information at the meeting of. March 7, 1980 (March 17, 1980).
25V' Licensee'.s letter to the-NRC with 3163 3676 summary. tables prepared'by Bechtel-vhich describe the reinforcing steel in ' shear wall panels of ths Control-Auxiliary-Fuel Building Complex (March 20, 1980).
4
Admitted Into No.
Licensee ~~.hibits Identified Evidence 23W Licensee's letter to the NRC with 3668 3676 design criteria prepared by Bechtel for the A-frate supports (March 21, 1980).
25X Licensee's letter to the NRC with 3668 3676 additional information prepared by Bechtel regarding the A-frame sup-ports (March 27,1980).
26A Licensee's resconses to Interroga-3669 3676 tories dated Ahgust 27, 1979 from the State cf Cregon (September 17, 1979).
263 Licensee's supplemental responses to 3669 3676 Interrogatories dated August 27, 1979 frca the State of Oregon (February 29, 1980).
27 Licensee's Testimony ("Brochl, et al.")
3669 3694 on Matters Other Than Structuraf- --
Adecuacy of the Modified Complex (Maich 17, 1980).
~'
23 Licensee's Testimony (" Anderson, 3669 4338 et al.") on the Structural Adequacy of tee Modified Complex (March 17, 1980).
29A Rev!ew of Proposed Design of Modifica-3669 4427 tions for Trojan Control Building, by Professors Myle J. Holley, Jr., and Soris 3:esler (March 13, 1980).
293 S:atement of Qualifications of 3669 4427 Myle J. Holley, Jr.
29C 5:stement of Qualifications of 3669 4427 Boris 3:esler.
30 Licersee's Resoonses to McCollon's 3670 4338 Preh>_aring Conference Qucstions, March l'-,
19S0 (March 31,1980).
J
Admitted Into No.
Licensee Exhibits Identified Evidence 31 S*_ ides Used in. oral Testimony of 4347 4453 Mr. R. C. Anderson and Dr. William H. White on March 31, 1980.
32 Licensee's Answers to NRC Staff 4448 4C85 Questions of March 30, 1980 (April 2, 1983).
33 Licensee's responses prepared by 4509 4685 Sechtel to NRC Staff auestions of April 3,1930 (April I4,1980)..
34 Licensee's " Report on Tests of Shear.
4525 4687 S:rength of Cellar Joint Mortar In Doub's Wythe Masonry Walls" (April 15, 1980).
35 Licensee's letter with attachments 4778 4778 to NRC providing PGE comments on
" Report on Design Criteria for Masonry Walls in the Trojan Nuclear Power Plant" by Dr. James Colville (March 15, 1980).
36A Licensee's responses -to NRC Staff 4822 4821-22 cuestions of December 29, 1979 (Ja cech er. 31, 1979).
363 Lf. 4nsee's response to NRC Staff 4822 4821-22 Ques: ion 6 of December 29, 1979 (January 9,1980).
I 36C Licensee's response to NRC Staff 4822 4821-22 Question la of Decer.ber 29, 1979
-(January 18, 1980).
363 Licensee 's response to NRC Staff 4822 4821-22 Ques: ion 5 of December 29, 1979 (January 31, 1980)-
35E Licensee'ss response to NRC Staff 4823 4821-22 Ques:icn 6 cf December 29, 1979 (February 9,1980).
35?
Licensee's resconse to NRC Staff 4823 4821-22 Question"1 of December 29, 1979 (February ' 5, 1980).
- 8
\\;
'Adritted Into No.
Licensee Exhibits Identified Evidence 36G Licensee's response to NRC-Staff 4823 4821-22 Question 12 of December 29, 1979 (March -5, 1980).
2 41 Licensee's " Addendum 1, March 1980, 4823 4821-22 to Report on Testing of Composite Masonry Walls" (April 1, 1980).
Admitted Into No.
NRC' Staff Exhibits Identified Evidence 12 NRC Staff Testimony of Charles M.
4004 4073 Tra=nell, 'III,. Identifying Staff Personnel Who Prepared the Safet Evaluati'on Report and Responding to Licensing Board-Question on Procosed License Condition (March 17, 1980).
13A Safety Evaluation by the Office of 4005 4005 Nuclear Reactor ReguIation Relating to Design Modi ~ications to the Con-trol Building (February 14, 1980).
133 Letter of A. Schwencer transmitting 4005
'4018 errata co URC Staff Safety Evaluation Report (February 15, 1980).
14 NRC Staff Testimony of Fred Clecenson.
4005 4074
'and Janes E. Knight Regarding Modifi-cacien Work and Effects on Plant Coeration and on Safety-Related:
L' uipment (March 17,- 1980).
q
-15 SRC~ Staff Testimony of Kenneth S.
4006-(rithdrawn
' Herring and Drew Persinko on CFSF at 4505)
ContentiensL20, 12/13 and 16
' March 17,1950).
15A SRC. Staff Revised Te.:tinony1of 4504 4579 Kennerh S. Herring and Drew Persinko en CFSPicontentions 20, 12/13 and 16 and.cn Structural Aspects of the Modification York Itself.
(Supercedes tExh.115).
-a Admitted Into No.
NRC Staff Exhibits Identified Evidence 15 NRC Staff Testimony of Charles M..
4006 4308 Tra=: ell, III, on Ques'. ions R:garding Relecation of the Railroad S >ar and Reductica in= Size of an Equipment Match Under the Proposed Modifications (March 17,1980).
17 NRC Staff Testimony of Kenneth S.
4006 (withdrawn Herring and Drew'Persinko on the at 4504)
Structural Adequacy cf the Proposed Modifications to the Trejan Control 3tilding (March 24, 1960).
17A NRC Staff Revised-Testir.ony of 4504 4679
.Kenneth S. Herring and Drew Persinko on the Structural Adequacy of the Proposed Modifications to the Troj an Control building (Supercedes EAh. 17).
15 Report on Concrete Masonry Wall 4007 4007 Jesign Criteria for Transverse Leadings (February 22, 1980).
19 ~
" Report on Dasign Cri'teria for 4531 4541 Masonry Walls in the T: jan Nuclear
?cwer Plant" (attachcent to February 22, 1980 Board notification letter).
23 "Co==ents on Documentation Sub-4532 4581 stantiating 18 psi Allowable Collar Shear Stress" (April 8, 1980).
21
" Response to Comments on Appendix B 4532 4581 of Dr. Co'_ville's Report of 2/13/80 on Trojan Masonry Walls" (April 8, 1980).
22
" Concents en Review hv Professor 4532 4551
- 3. 3resler of Evaluation of Tensile Sand and Shear Sond of Masonry by Means of Cen rifugal Force, by M. Hatzinikolas, J. Longworth and J. *.Jarwaruk, Alberta Masonry Institute
- Jndated '(197 3-197 9)" - by-Dr. James Calville.(April a, 1950).
rs
o 8-s Admitted Into-
'o.
NRC Staff Enhibitc~
Identified Evidence 23-Letter of. Joseph Gray transmitting 4682-4683 Affidavit of Charles E. Gaskin re NRC Staff 3 valuation of additional security review (Aaril 11, 1980)
(=arked-for identif'ication only).
24
-Letter of R. M.,Engelken to' Licensee 4694 4786 re short-term testing results of double ~-wythe casonry walls with '
r.ortared collar-joints- (April 17, 1930).
Admitted Into
- o.
State of Oregon's Exhibit Identified Evidence 2
Testimony of. Harold I. Laursen on 4457 4461 Behalf'of the State of Oregon-l Regarding Structural Adecuacy of the-Modified Complex-(March 21, 1980).
2A'
. Supplement' to the Testinony._of 4651 4664
'Earold I. Laursen Regarding the Adecuacy.of the Proposed Modification of the Troj an ~ Nuclear Plant Control Building s
1 2
_