CLI-79-11, Safety Evaluation Re Pile Foundation Design & Installation for Facility.Licensee May Drive safety-related Piles for Main Power Block Per 780308 Proposal for Foundation Mat. CLI-79-11 Encl
| ML19347D336 | |
| Person / Time | |
|---|---|
| Site: | Bailly |
| Issue date: | 03/31/1981 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML19347D334 | List: |
| References | |
| NUDOCS 8103170196 | |
| Download: ML19347D336 (48) | |
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SAFETY EVAll'ATION REPCRT Related to the Pile Foundation Design and Installation for the BAILLY GENERATING STATION, FL' CLEAR-1 Cocket No. 5?-367 Northern Indiana Public Service Ccrpany March 1981 81031 70 Mf
i.
TABLE OF CCHTENTS PACE
1.0 INTRODUCTION
AND GENERAL DISCUSSICH...................
I 1.1 Introduction 1
1.2 Description of Present Foundation Conditions 4
1.3 Pesolution of the Foundation Conditions at the CP Stage......
6 1.4 Shorter Pile Proposal.......................
7 1.5 Outstanding Issues 8
-2.0
SUMMARY
OF THE STAFF' S REVIEW....................
9 2.1 Indicator Pile Program 9
2.2 Design Leadings and Structural Analysis..............
9 2.3 Pil e Capa ci ti e s..........................
11 2.3.1 Factors of Safety 11 2.3.2 Maximum Design Loads....................
11 2.3.3 Required Corpressive Load Capacity............. 12 2.3.4 Recuired Lateral Load Capability..............
14 2.3.5 Required Upli f t Capability...........
16 2.3.6 Capacities of Pile Groups 17 2.4 Driving Recuirements 17 2.5 Veri fica tion 7es t Program.....................
18 2.6 Acceptance of the Indicator Piles as Safety-Related........ 19 2.7 Settlement of the Foundation Pat 19 2.8 Pile Heave 21 2.9 Densification of Preconstruction Areas 22 1
TABLE OF CONTENTS (Cent'd)
PAGE 2.10 ACRS' Corrents on the Shorter Pile Preposal............ 24 2.11 Potential for Corrosion of the Piles 25 2.12 Groundwater and Site Dewatering Effects on Pile Installation 26 2.13 Field Installation Requirements..................
28 2.14 Inspection and Field Ponitoring.................. 30 2.15 0A/0C For Pile Install ation....................
31 3.0 CUTSTANDING ISSUES 32 3.1 Review of the Pile Loads......................
32 3.2 Foundations Outside the Main Power Block.............. 33 3.3 Long-Term Groundwater Considerations................ 33 3.4 Backfilling 33 3.5 Pile Group Capacity 34
4.0 CONCLUSION
S............................... 35 APPENDIX A
'ACRS' C0tEENTS ON THE BAILLY SHORT PILE PROPOSAL APPENDIX B STAFF INTERPRETATION OF AN ACRS RE0VIREMENT APPENDIX C C0FNISSION NEMORANDUM AND ORDER ON BAILLY, DECEMBER 12, 1979 11
1.0 INTRODUCTION
AND GENERAL DISCUSSION 1.1 Introduction On February 15, 1972, the then Atomic Energy Corrission (Commission) issued its Safety Evaluation Report in the matter of Northern Indiana Public Service Company's (NIPSCO) application to construct the Bailly Generating Station, Nuclear 1, (Bailly facility). The Safety Evaluation Report (SER) was later supplemented by Supplements Nos.1 and 2 which described the resolution of outstanding issues.
On May 1,1974, Construction Permit Number CPPR-104 was issued for the Bailly facility following extensive hearings before an Atomic Safety and Licensing Board (ASLB) and subseauent appeals to the Atomic Safety and Licensina Appeal Board (ASLAB), the Commission and to the fedcral courts. During the early summer of 1974, work was initiated at the Bailly site by the licensee, HIPSCO, and continued until a stay of contruction was issued by the Seventh Circuit of the U. S. Cou-t of Appeals. This initial site work was primarily oriented towards establishing the detailed design for the safety-related pile foundation, including the placement requirerents, for the Bailly facility.
Subsequent to the lifting in late 1976 of the last legal constraints against any further construction activity at the Bailly site, the licensee reinstituted construction activities at the site. This work primarily consisted of installing a construction dewatering system at the site to lower the existing groundwater level to pennit access of heavy pile-driving eauipment into the foundation excavation. This system was installed in accordance with Amendment No.1 to the Construction Permit (CP), issued on December 22, 1976. At this time, the principal components of this system are a slurry wall completely encir the excavation and shallow well points. Further excavation down to an elt,ation about eight feet above the mean level of Lake Michigan was then accomplished.
2 In September 1977, the licensee submitted to the staff of the t'uclear Pegulatory Commission (flRC), its details for a proposal initially rade in December 1976, for installing the safety-related piles using a jetting technioue. After the staff witnessed a pile being installed by this method and following extensive staff review of this proposal, the Director of Project Managerent issued a letter on February 11, 1978, stating that the licensee was not to install any safety-related piles at the Bailly site until the staff had reviewed and approved the detailed requirements for the installation of these piles. Subsequently, the licensee submitted on March P, 1978, a report on the design analysis and the installation of conventionally driven H-piles. The technical thrust of the licensee's proposal is to drive the piles in a conventional manner into the dense, over-consolidated, interbedded placial-lacustrine sand / clay stratum underlying the site.
Inasruch as the elevation of the pile tips will be higher than the elevation discussed in the licensee's Preliminary Safety Analysis Report (PSAR), this proposal is referred to as the shorter pile proposal.
It is the licensee's position that this stratum will provide an ecceptable bearing layer for the safety-related piles. On this basis, the licensee states that it satisfies one of the staff's two principal architectural and engineering criteria for the foundation piles; namely, that the piles have a high capacity. By using steel H-piles without a driving shoe, the licensee states that it thereby satisfies the other principal criteria; namely, that the piles be non-displacement. The original short pile proposal has been subseouently modified during the course of our review.
The staff's two criteria cited above were contained in Section 5.5.1 of the staff's SEF Snd were the basis at the CP stage for ur acceptance of a pile foundation for the Bailly facility.
. The staff reccgnized when it issued the SER, however, that more werk by HIPSCO was required after issuance of the CP to establish sufficient engineering details which would pennit the staff to accept the cceplete design of the pile foundation.
To this end, we stated in the SER that we would follow this ratter during construction.
part of the work which was anticipated by the staff in this statement was the pile driving activities conducted by the licensee on the site during the surmer of 1974. This on-site sctivity would then be factored into the design of the pile foundation.
Our review of the licensee's shorter pile proposal is based on evaluating the corpliance of the proposal with the criteria identified in the SER as well as deternining the compliance of the proposal with prudent, state-of-the-art engineering practice for pils foundations. To assist us in this latter evaluation, we have retained as censultants, the U. S. Arry Corps of Engineers and Dr. M. T.
Davisson of the University of Illinois. They were selected for their expertise in pile foundatMns; their advice has been used in establishing cur findings and conclusiens on this matter.
While we have not completed our review of all aspects of the proposed Bailly foundation, we have found that those limited matters outstandina do not affect our basic conclusions regarding the acceptability of the shorter pile proposal and do not affect our decision regarding the restart of construction activities.
. Appendix A contains the letter from the Advisory Cormittee on Reactor Safeguards (ACRS) to the NRC Chairman on this ratter.
In this letter, the ACRS states its finding that the shorter pile proposal does not represent undue risk to the health and safety of the public and the ACRS established five requirements for the shorter pile proposal. The staff finds that these requirements have been met by the shorter pile proposal. Appendix B contains a technical interpretation by the staff of one of these requirements.
On the basis of our review, including the advice of our consultants, we conclude that the licensee may drive the safety-related piles for the Bailly facility's foundation in accordance with the Parch P,1078, proposal including the subseouent submittals on this matter.
1.2 Description of Present Foundation Conditions The Bailly plant site is located on the southern shore of Lake Michigan in an area where the indigenous sand dunes have been leveled at an elevation of about
+40 feet measured above the rean lake level of Lake Nichigan. The site is underlain by about 180 feet of glacial and post-glacial soil deposits which in turn are underlain by bedrock which is limestone and dolomite; the urderlying bedrock is encountered at an elevation of about -140 feet. There is a glacial till deposit which is about 10 to 20 feet thick over this bedrock. The licensee ha's presented a generalized soil profile beneath the power block. The approximate base elevations of the various deposits are:
. Stratum Pase Elevation of Stratun (feet) eolian (dune) sand
+20 to +10 glacial-lacustrine (beach) sand
-10 glacial-lacustrine clay
-10 (south end) to -90 (north end) interbedded glacial-lacustrine sand / clay
-90 to -100 glacial-lacustrine clay
-100 to -120 The upper glacial-lacustrine clay stratum whose base elevation is -10 feet to -90 feet, is compressible. The interbedd:d glacial-lacustrine sand / clay stratum consists of very dense, fine sand with layers and lenses of hard, silty clay. The lower glacial lacustrine clay is hard and has low conpressibility.
The groundwater level in the eolian deposit is at an elevation of about +25 feet at the southern end of the Bailly site and +15 feet at the northern end of the site.
There is also an artesian condition in the interbedded glacial deposit where the piezoretric level ray range from an elevation of zero to +25 feet.
The foundation excavations will extend to an elevation of about zero feet for the radwaste building and about -7 feet for the reactor building. Since the normal groundwater level is above the bottom of the foundation excavations, site dewatering is necessary for placement of the piles, pouring of the concrete foundation mat and construction of the lower portion of the buildings in the main power block.
To accomplish this construction dewatering, a dewatering system was installed in 1977 which consists of: (1) a slurry cut-off wall extending into the glacial-lacustrine clay and which intercepts the water in the glacial-lacustrine sand; and (2) shallow well points. Since there is an artesian condition in the interbedded glacial-lacustrine
4 e sand / clay stratum, a deep well point system is also needed to minimize the potential for uplift and/or sand boils in the excavation.
(Refer to Section 2.12 of this evaluation).
1.3 Resolution of the Foundation Concerns at the Construction permit Stace Our original concern with the foundation conditions was that the glacial-lacustrine clay stratum is compressible so that any significant loading on this stratum would result in slow, long-term settlements. This would not be a major concern for the safety-related structures were the settlement to occur uniformly though some engineering approach would be reouired to minimize the stresses in buried pipes attached to buildings. However, the varying structural loading on the soil under each of the buildings would tend to cause differential settlements between the safety-related structures. Additionally, since the thickness of the upper, compressible glacial-lacustrine clay layer varies from almost zero at the southern end of the site to about P0 feet in the northern end, compression of this wedge-shaped clay layer could cause unacceptable differential settlements if the facility were to be supported on a mat founded above this compressible clay stratum.
Accordingly, the licensee proposed at the CP stage to drive piles through this layer to a depth where there was assurance that the piles would be supported in an acceptable manner.
In its Preliminary Safety Analysis Report, the licensee stated that this depth probably would be at the elevation of the glacial till or the underlying bedrock. The staff concluded in its Safety Evaluatica Report (SER) that a pile foundation was acceptable based on two criteria for the piles; i.e., that the piles be non-displacement and have a high capacity. The staff further stated, however, that it would follow this matter during construction
. recognizing that the licensee had to provide additional information regarding the particular type of piles to be used and the requirements for their installa-tion prior to our acceptance of the licensee's proposal implerenting the principal architectural and engineering criteria for the safety-related piles cited above. (Refer to Section 5.5.1 of the SER).
We did not reouire as a condition of the CP issued on May 1,1974, any specific pile tip elevation or require that the pile tips be bedded in any specific stratum. We still maintain this posture except as modified by the proposed installation reauirements which we discuss in this evaluation and which we find acceptable. (Refer to Sections 2.2 and 2.4 of this evaluatien).
1.4 Shorter Pile Proposal The applicant proposed in flarch 1978 and in its subsequent submittals, to use 14 HP117 and 14 HP89 steel H-piles driven into the interbedded placial-lacustrine sand / clay stratum and provided proposed driving requirements and installation detail s. This proposed implementation of the licensee's CP corritment to install a pile foundation is identified as the shorter pile proposal. This proposal is based on the licensee's position that an acceptable bearing layer for the piles exists at elevations that are much higher than the elevations cf either the glacial till or the underlying bedrock. In this regard, the if censee's proposal is consistent with the staff's position on the matter of the elevation of the pile tips as discussed in the preceding section. Based on the indicator pile program (refer to Section 2.1 of this evaluation), the licensee estimates that the top of the bearing layer is at an elevation of about -11 feet at the southern end of the power block and about -100 feet at the northern end of the power block.
.e.
1.5 Outstanding Issues There are a limited nurber of outstanding safety issues associated with the
'Bailly pile foundation. These are:
a.
Review of the pile loads (refer to Section 3.1).
b.
Foundations outside the main power block (refer to Section 3.2).
c.
Long-term groundwater considerations (refer to Section 3.3).
d.
Backfilling (refer to Section 3.4).
e.
File group capacities (refer to Section 3.5).
These matters do not affect our finding and conclusion that placement of the safety-related piles is now acceptable.
Li -
. 2.0 SUMPARY OF THE STAFF'S REVIEW 2.1 Indicator Pile Program The licensee has supplerented the original subsurface investigation and laboratory soil testing program that was reviewed by the staff prior to issuance of the SER in February 1972 with a pile test program in 1978; this latter program is identified as the indicator pile program. The licensee conducted this program in response to a requirement we established as part of our review of the shorter pile proposal. In this prcgram, the licensee installed about 130 piles representing about four percent of the piles for the safety-related structures of the main power block. Some of these piles were load tested. Our review of the shorter pile proposal is based extensively but not exclusively on the results of the indicator pile program. On the basis that this program represents prudent engineering and construction practice for a pile foundation, we find that the indicator pile program provides a portion of our basis for an evaluation of the prcposed pile installation program. We also base our review of the shorter pile proposal on our analytical evaluations and on our judcment and that of our consultants, the U. S. Army Corps of Engineers and Dr. M. T. Davisson of the University of Illinois.
2.2 Design Loadings and Structural Analysis The licensee has calculated the loads on the safety-related piles for several design conditions; i.e., normal, construction and testing, abnormal, severe environmental and extreme environmental conditions. The severe environmental and extreme environmental design conditions include seismic loadings.
. We and our consultants have previously reviewed and found acceptable, the procedures the licensee proposes to use for the structural design and analysis of the safety-related structures.
(Refer to Appendix I in the SER issued in February 1972). The analytical modeling of the safety-related buildings at the CP stage of our review was based on representing the structural behavior (i.e., the deformation under load) of the piles as sprinos. While the length of the piles may affect the numerical value of the eouivalent spring constant, the actual length of the piles and the physical manner in which the loads in the piles are transferred from the piles to the soil and thence to the underlying rock, does not change the methods of structural analysis which we found acceptable at the CP stage of our review. Accordingly, the change in pile length associated with the present shorter pile proposal does not change our previous conclusion regarding the methods of structural analysis.
Additionally, the load capabilities of the production piles will be significantly greater than that required for the maximun pile design loads calculated by the licensee. (Refer to Section 2.3.3 of this evaluation).
Based on the dual considerations that the licensee's analytical design methods remain acceptable and that there is ample margin in the load capability of the production piles, we find there is reasonable assurance
~
that the pile factors of safety required by the staff, will be achieved.
Accordingly, we find that further detailed review of the licensee's calculated pile loads is not necessary at this tire. The staff will
. verify the acceptability of the licensee's calculated foundation loadings, including our evaluation of the actual factors of safety, after the structural design has been completed and the load capability of the production piles has been confirmed by field tests.
2.3 Pile Capacities 2.3.1 Factors of Safety The staff has required and the licensee has adopted, the following minimum factors of safety for the safety-related piles:
Load Condition Minimum Factor of Safety normal, construction and testing 2.5 abnormal 2.0 severe environmental 2.0 abnormal / severe environrental 1.75 extreme environmental 1.5 abnormal / extreme environmental 1.5 Based on the existing Bailly site conditions, customary geotechnical engineering practice and the advice of our consultants, we find these factors of safety to be acceptable.
2.3.2 Maximum Design Loads The applicant has calculated the following maximun design loads:
t.
. Maxirun Pesign Load, Tons Load Condition Ccroression Uplift Lateral normal, construction and testing 150 abnormal 150 severe environmental
- 190 abnormal / severe environmental
- 190 extreme environmental
- 220 65 14.2 abnormal / extreme environmental
- 220 65 14.2 The calculated maximum loads occur only on those piles on the periphery of the buildings; most of the piles will have lower loads. This phenonenon reflects the increase in pile loads caused by the overturning moment on the safety-related structures arising from the seismic loading. This pattern of structural loading on the piles represents an additional conservatism since some of the load on the more heavily-loaded peripheral piles can be distributed by the relatively stiff foundation mat to the more lightly-loaded interior piles. The lateral and uplif t loads are generated primarily by the seismic loading and are transient.
A 2.3.3 Recuired Corpressive Load Capacity The licensee has specified that each safety-related pile will be capab'e of supporting a minimum ultimate compressive load of 400 tons. We conclude that this minimum pile load capability is conservative based on the following considerations:
a.
The indicator pile program conducted in 1978 has demonstrated that the required compression capacity of 400 tons per pile can be attained on high capacity, non-displacerent piles driven into the very dense
- Includes earthauake
- flegligible
. glacial-lacustrine sand / clay deposits using driving requirements comparable to those presently proposed for the production piles. Indicator piles placed according to these requirements were driven to depths of about 30 to 80 feet below the level of the present excavation; i.e., to elevations ~of about -23 feet to -73 feet below the mean level of Lake Michigan. In particular, the field load tests in the indicator pile program have shown ultimate pile load capacities ranging from about 490 tons to 600 tons. The piles may have been capable of carrying a greater compressive load since the maximun load achieved was limited by the load testing arrangement. Additional load tests will be conducted to confirm that the pile capacity and behavior observed in the indicator pile program is comparable to that for the production piles.
(Refer to Section 2.5 of this evaluation.)
b.
The licensee has performed " wave ecuation" analyses for the three piles which were load tested and compared the results of these analyses with the results of the pile load tests. The method of analyzing pile load capacity known as the wave equation method is a state-of-the-art procedure using dynanic analysis to determine the static load capability and is acceptable to the staff. The results of these analyses indicate that the values of the calculated ultimate loads are compatible with the specified ultimate load capability of 400 tons. The staff independently verified the results of the licensee's wave equation analyses. Both the licensee's and our calculations demonstrate that the miniasm design capacity specified by the licensee is justifiable using commonly accepted analytical methods.
. c.
The pile driving records from the indicator pile program and a comparison of the load capability determined in the wave ecuation analyses with the pile load test results both indicate that additional pile capacity is expected to develop through the phenorenon identified as soil freeze.
Inasruch as this additional pile load capacity will raise the ultimate pile load capability above that calculated by the wave equation method, this phenomenon will provide added conservatism cver that established in the driving criteria.
To verify and quantify this additional load capacity contributed by soil freeze, part of the production pile test progran will evaluate those indicator piles which have been in the ground since 1078.
This will include both redriving these piles and load testing them.
(Refer to Section 2.5 of this evaluation.)
2.3.4 Required Lateral Load Capacity 2.3.4.1 Pile Ceflection Under Lateral Load The ultimate lateral load capacity of the piles is not in itself a significant factor in the evaluation of the shorter pile proposal.
Even though the piles can carry relatively large lateral loads, they would do so with concomitant large lateral deformations. The relevant factor in establishing the allowable lateral load on the piles is the allowable lateral deflection under the design loads.
The allowable lateral deflection in turn is deternined by the structural problems that would result if excessive lateral deflections of the safety-related structures were to occur (e.g., excessive pipe stresses).
We find that there is reasonable assurance that the piles will not
1
. have excessive deflections under the design basis loads based on the following considerations:
a.
The lateral deformation under the maximum design lateral load calculated by the licensee (i.e.,14.2 tons), was about 0.7 inches when the load was applied cyclically in the October 1977 lateral load test on a pile in the turbine building area.
b.
The piles will be deeply embedded (i.e., about three feet) and well anchored with reinforcing steel bars into a rigid pile cap (i.e., the foundation mat) which will restrain rotation of the pile butts, thereby reducing the lateral deformation of the piles under lateral loading. This restraint was not present in the lateral load test.
c.
The load testing procedure under which the lateral load is applied relatively slowly is conservative since the earthquake loading which is applied rapidly will give smaller deflections than those measured in the test program. This phenomenon can be attributed primarily to the visco-elastic behavior of the soil.
d.
Lateral load tests will be performed on the production piles. While the results from these additional lateral load tests are expected to be similar to the previous test results obtained from the turbine building pile, they will be performed as confirmatory tests demonstrating that the previous test was representative.
. 2.3.4.2 Pile Stresses Under Lateral Lead The licensee has analyzed the pile stresses for both corpression and lateral loading since this load combination is core critical than for lateral loading alone. The licensee's calculations indicate that the piles will not be overstressed due to this combined loading. We agree that the licensee's calculations support this conclusion. Moreover, the pile driving specifications are designed to minimize pile splices in the upper 20 feet of the pile which is the portion of the piles where bending stresses under lateral loading are significant.
(Refer to Section 2.13(c) of this evaluation.)
2.3.5 Reauired Uplift Load Capacity The uplift capacity of the indicator piles was measured in two separate uplift load tests. The first test involving two test piles was performed in flay 1974 and the second test also involving two test piles was performed in January 1978. Both tests were conducted outside the main power block.
The lowest uplift capacity reasured was 240 tons. The licensee cermits to provide an adequate pile erbedrent in soil for those piles subjected to uplift loads; i.e., piles located on the periphery of the buildings. Specifically, these piles will be embedded in soil to a depth at least eaual to the driven length of those piles tested for uplift capacity. We find these procedures to be acceptable based on the following considerations:
a.
The piles tested in 1974 and 1978 bad uplif t capacities much greater than the reouf red capacity (i.e., 65 tons as shown in Section 2.3.2 of this evaluation).
b.
Uplift load tests will be performed on the production piles to confirm tha uplif t load capacity and deronstrate that the previcus tests outside the main power block were representative.
. c.
Additional uplif t capacity due to the load redistribution by shear in the rigid foundation mat has been conservatively neglected.
2.3.6 Capacities of Pile Groups The staff has not completed its review of the effects of pile group action but does not anticipate any significant differences with the conclusion of the licensee in this matter. Based on our judgment and the advise of our consultants, any differences that may develop are expected to be minor. These minor differences can be readily accommodated, if required, by minor changes in the pile layout details before pile driving is completed.
(Refer to Section 3.1.1 of this evaluation).
2.4 Driving Reautrements The driving requirements proposed by the licensee state that the piles he driven with a Vulcan 016 steam hammer, or equivalent, with an energy rating of d8,000 foot-pounds per blow. Additional proposed driving recuirements are: (1) 500 blows for the last five feet or less of penetration; (2) 100 blows for the last one foot or less of penetration; and (3) 10 blows per inch for the last 3 inches of penetration. The purpose of this latter driving requirement is to verify that the piles are seated in a competent stratum in the bearing layer. This will be accomplished by determining that the rate of penetration of the piles at the conclusion of driving shall be not less than 10 blows per inch. Since this requirement is necessary to support the assumptions in the wave equation analysis, a lower rate of penetration in the last three inches of penetration is not acceptable.
The pile tips are also required by the driving recuirements to penetrate at least three feet into the bearing layer. Some minor variations to these
. driving criteria have also been proposed to account for special field conditions; e.g., restarting pile driving after a delay. Pile driving records will be obtained for all piles.
We find these proposed driving recuirements ars reasonable and conservative since the wave equation calculations and the load tests on the indicator piles have shown that these criteria can provide more than the required load capacities, as discussed in Section 2.3.3 of this evaluation. Based on these considerations, we conclude that the proposed driving requirements are acceptable.
2.5 Verification Test Program The load testing program for the production piles proposed by the licensee to supplement the pile load tests conducted during the indicator pile program, will verify the pile load capacity for the following soil-pile conditions:
a.
Piles driven to the bearing layer through a thick clay layer on the northern end of the site and through a thin clay layer on the southern end of the site.
b.
Individual piles whose driving resistance characteristics differ significantly from the behavior of the majority of the piles. Specifically, those piles whose driving records are classified by the licensee as type "A" represent the majority of the piles; type "B" represents the remainder of the piles.
c.
Piles penetrating compressible materic:s for which the long-term settlement behavior has not yet been detemihed, d.
Piles which have been allowed to set for a long time, thereby permitting the soil freeze phenomenon to develop.
I
. e.
Piles which satisfy the driving specifications at relatively short lengths in comparison to the other production piles.
Since the proposed field test program for the production piles incorporates all the significant soil-pile conditions that are expected to be encountered at the site and Since the enhanced field inspection and testing program (refer to Section 2.13 of this evaluation), provides assurance that appropriate load tests will be properly performed, we find that the pile load verifica-tion tests proposed by the licensee can be expected to confirm the design pile load capability.
2.6 Acceptance of the Indicator Piles As Safety-Related The piles installed as part of the indicator pile program will be accepted for use es safety-related piles only if their installation met or exceeded the presently proposed driving requirements. Some of the indicator piles I
will need to be redriven and some may be abandoned. Accordingly, we find the licensee's proposal to support the safety-related plant structures on the indicator piles to be acceptable since only those indicator piles which i
satisfy the presently proposed driving requirements, will be used.
2.7 Settlement of the Foundation Mat The licensee has calculated two sets of settlements which it describes as
" upper bound" and " realistic." The realistic estimate was based on soil modulf corrected for sample disturbance and for the expected proportion of clay in the bearing layer. The upper bound estimate was based on a very conservative estimate of the properties of the clay below the pile tips. The settlement calculations were based on data obtained from 14 consolidation tests performed on undisturbed samples. The test results provide sufficient evidence that the
. i bearing layer is heavily over-consolidated. Accordingly, the recorpression range of the consolidation curve was used in the calculations o' settlements. We agree with this approach.
In performing the calculations, the licensee used a generalized soil profile and divided the foundation into 50 finite element rectangles for the mathematical modeling of the settlerent. Pfle loads were applied as uniform loads of varying intensity in each rectangle at the expected pile tip elevations. The calculated settlements include elastic pile compression and account for the stiffness of the foundation mat. Local stress concentrations at the pile tips were accounted for by varying the mesh size at the pile tips.
The most heavily loaded part of the foundation nat is that portion under the reactor building and, therefore, the largest estimated settlements occur under this structure. The licensee's estirated settlerent at this location is one and three-cuarters inches for a " realistic" calculation and two and three-ouarters inches for the " upper bound" calculation.
We find that the licensee has used both reasoncble methods and assumptions in its settlement calculations and that the maximum settlerent should be less than two and three-quarters inches. We also find that a major portion of the settlement should occur during construction and prior to operation of the plant since the predominant loading on the foundation is the dead load imposed by the plant. Accordingly, we conclude that only minor settlements will occur after the plant is completed and that these minor settlements will not have a significant irpact on the safe operation of the plant. Furtherrore, any settlements that do occur can be properly accornodated by a number of existing engineering measures
s,
so that f7undation settlements will not have an adverse effect on the safety of the plant.
To confirm these conclusions regarding the settlement estimates, the licensee has proposed to perform long-term measurerents of individual pile settlements under load as part of the pile load test program on the production piles.
(Refer to Section 2.5 of this evaluation.) In addition, the settlement of the foundation mat will be monitored frequently during construction. We find that the foundation settlements will t'e properly assessed prior to completion of construction of the facility and will be properly monitored during construction and operation of the plant. Accordingly, the settlement monitoring progran is acceptable.
On the basis of all the foregoing considerations, we find that the settlement of the foundation mat will not adversely affect the safe operation of the plant and, therefore, is acceptable.
2.8 Pile Heave The large number of piles and their close spacing under some parts of the foundation (e.g., the reactor building) represents a potential for previously driven piles to heave as adjacent piles are driven. Our concern in this matter is that the tip of a heaved pile might not maintain firm contact with the soil (i.e., it might unseat), thereby reducing the effective load capacity of the pile as defined by its deflection-load characteristics. The licensee investigated this phenomenon in the indicator pile program by driving a cluster of 40 piles and measuring the resulting heave. The maximum heave was less than one and one-half inches. Subsequent deflection-load tests indicated that the piles which heaved had not been unseated from the bearing layer and that the heaving
. had not compromised pile capacity. On this basis, the licensee asserts that a pile heave of one inch would be an acceptable limit before remedial redriving would be needed.
The staff did not agree with the licensee's position on this matter and accordingly required the licensee to revise its specifications to state that the piles will be driven in a manner which will ensure that the heave on any pile at completion of the production pile installation, be less than 0.5 inches.
If redriving causes any piles to heave in excess of 0.5 inches, we require the licensee to evaluate these piles and develop a disposition using a Non-Conforrance Report (NCR) procedure. We have informed the licensee that either load testing or additional redriving is the preferred disposition of the NCR for those piles heaving more than 1.0 inches.
In response to this staff position, the licensee proposes to redrive all piles after adjacent piles have been driven and take appropriate corrective measures if any final heave (i.e., after redriving) is greater than 0.5 inches. We agree that this approach is conservative and, therefore, find this approach to be acceptable.
2.9 Densification of Preconstruction Areas The licensee employed a jetting process and/or pulled piles in five areas of the foundation excavation; these are identified as preconstruction areas. The first process loosened and removed significant quantities of soil around the pile tip by means of a high pressure water jet as the piles were vibrated down. Pulling of previously driven piles left voids and/or soil regions of decreased density.
These five areas are considered to be unsuitable in their present condition for pile installation due to the localized reduction in the soil density. Driving
. non-displacerent piles in these five areas without improving the subsurface conditions would be unacceptable since piles driven in these areas could: (1) have excessive lateral deflection under lateral load; and (2) be significantly longer than piles driven in the undisturbed portions of the site.
If these piles are significantly longer, they could experience differential settlerent with respect to the adjacent piles, thereby producing increased localized stresses in the foundation mat which could lead to cracking in the mat and in the safety-related buildings supported on the mat. Any cracking in the reactor building walls could compromise the integrity of the containment building. Accordingly, the licensee proposes to densify these preconstruction areas by driving clcsed-end,10-inch diameter, pipe piles in the preconstruction areas to increase the soil densities of the disturbed areas.
To determine whether the densification progran achieves its goal, driving resistances will be recorded for the densification pipe piles driven in the preconstruction areas and compared with driving records for similar pipes piles driven outside the preconstruction areas. The acceptance criterion for terminating the densification program in any of the disturbed areas is that these pipe piles achieve driving resistances comparable to those obtained on pipe piles driven outside the preconstruction areas. Furthermore, the driving records for the production H-piles driven in the preconstruction areas will be compared with those for production piles driven in undisturbed areas so as to provide verification that the driving characteristics in the preconstruction areas, after ccmpletion of the densification program, are comparable to those in the undisturbed portions of the site. Finally, additional verification of the adequacy of the production piles driven in the preconstruction areas will be obtained by performing load tests on sore of these piles. (Refer to Section 2.5 of this evaluation).
. We find that the densification progrem proposed by the licensee for the five preconstruction areas will achieve its stated goal since the displacerent piles can restore the characteristics of the disturbed soil so that they are comparable to those in the undisturbed areas. Moreover, we find that the multiple verification procedures proposed by the licensee will provide assurance that the densification program is successful. Based on this, we find the proposed densification program to be acceptable.
2010 ACRS' Comments on the Shorter Pile Proposal In its letter to the Conmission, dated July 16, 1979, the ACRS found the proposed densification program for the preconstruction areas to be acceptable, subject to some conditions.
(Refer to Appendix A of this evaluation.) While the licensee agreed to these conditions in 1979, the staff and its consultants believe that one of these reouirements (i.e., exploration by penetration devices which will remove soil from the recorpacted areas) is not desirable since this will re-disturb these areas. We also believe that non-displacement types of tests (e.g., a penetrometer test) which do not remove soil, nay net be successful in the areas that have been densified. As stated in the preceding section, we find that the proposed densification program is acceptable but agree that, if additional verification data could be obtained, it would be useful. On this basis, the licensee has agreed to perform penetrometer tests in the preconstruction areas.
We have informed the ACRS of our position in this matter (Refer to Appendix B of this evaluation) and they have raised no objection to our interpretation that the intent of the ACRS requirements is: (1) all disturbed areas are identified; (2) the disturbed areas are adeouately densified; and (3) the adecuacy of the densification program is verified.
. In addition to the procedures adopted by the licensee, the staff and its consultants plan to closely monitor the installation of piles in the precon-struction areas to further satisfy the requirerents of the ACRS.
In the letter cited above, the ACRS also stated its recuirement that the adequacy of the settlement calculations be verified. The discussion in Section 2.7 of this evaluation addresses this requirement.
2.11 Potential for Corrosion of the Piles The licensee has investigated the potential for corrosion of the steel piles and asserts on the basis of its consultant's report that the piles will not be adversely affected by corrosion during the life of the plant. To confirm this position, the licensee conmits to install " witness" piles adjacent to the plant. These witness piles will be identical in all respects to the production piles and will be periodically pulled during the life of the plant to inspect them for corrosion damage.
If the witness piles show significant corrosion, a corrosion protection system will be installed and activated. To permit this corrosion protection system for the safety-related piles to be implemented in the event that it is required, the licensee proposes to install an electrical connection between the reinforcing steel bars in the foundation mat and the steel piles, prior to pouring the concrete for the foundation mat. This electrical connection would bu used to maintain an appropriate electrical charge on the piles. Systems which function on this principle have proven satisfactory in numerous applications with respect to both reliability and effectiveness.
We find the licensee's proposed corrosion protection plan to be acceptable since: (1) the piles will be monitored for corrosion throughout the life of
, the plant; (2) effective corrosion protection treasures can he installed and activated at any time during the life of the plant, if they are reouf red.
2.12 Groundwater and Site Dewatering Effects en Pile Installation Since the foundation excavation extends below the normal groundwater level, dewatering is necessary during construction of the plant. The groundwater level in the eolian deposits will be lowered to an elevation of about -7 feet during the early phases of construction and eventually will be permitted to rise to its natural state as construction is completed. The pile tips will be founded in the underlying glacial-lacustrine sand / clay stratum which is a confined aquifer.
We have three concerns regarding the construction dewatering program. The first is that fine soil particles might be pumped from around the well points, thereby creating voids which would degrade the site foundation. This phenomenon could occur during dewatering of eithee' the shallow or the confined acuf fers.
To address this concern, the licensee coreits to a program which will monitor the discharge from the dewatering systems to detect the presence of any significant amount of fine soil material. The program requires imediate action if a concentration of more than five parts per million (ppm) of sediment is detected in the discharge water. This action will require shutting down some or all of the pumps and instituting a number of standard engineering procedures for mitigating this problem if it should cccur. On a conservative basis, we estimate that this concentration represents a potential rereval of less than two cubic yards of material per year. We consider the loss of this quantity of material to be insignificant. On this basis, we find that the licensee's proposed procedures are acceptable.
. Our second concern is that excess hydrostatic pressures in the confined aquifer could cause either uplift or sand boils in the base of the excavation. Such a disturbance of the soil surrounding the piles would thereby degrade the site foundation. The licensee resolved our second concern by proposino to provide pressure relief in the confined acuifer. To do so, it proposes to install a deep, well point dewatering system.
Specifically, the licensee proposes to maintain the piezoeetric level in the confirmed acuf fer ;n the rance of -7 feet to +5 feet.
In all instances, the licensee comits to maintain the piezometric level low enough so that the overburden pressure is at least 1.3 times the excess hydrostatic pressure. We find that these proposed criteria and procedures are conservative and, therefore, are acceptable.
Finally, our third concern regarding dewatering during construction is that the measured pile capacity can be affected by the groundwater level when the prcduction piles are load tested. Basically, the pile load capacity is dependent on the effective stress conditions in the surrounding soil which in turn is dependent on the groundwater level. The licensee proposes to account for this phenomenon by recuiring that the groundwater level be close to the elevation of the bottom of the foundation mat during load testing of the production piles. Accordingly, we conclude that the production piles will be tested under the most adverse groundwater conditions that can be practically attained during this phase of construction.
It should be noted that groundwater levels higher than the level maintained during the pile load test program will reduce the compressive loads on the piles. On the basis of the foregoing considerations, we find that the licensee's proposal to account for the effect of the groundwater level on the measured pile load capacity is acceptable.
. 2.13 Field Installation Requirements In addition to the foregoing proposals, commitments and procedures, the if censee also commits to adhere to the following additional pile installation requirements:
Tolerances on the horizontal placement, rotational orientation and a.
vertical plumbness of the piles are proposed to provide assurance that the piles will be located in accordance with the assumptions used in the design of the foundation mat. Furthermore, these pile placement recuirements provide assurance that most piles will be placed within normal construction tolerances and that deviations will be adequately addressed by qualified engineers. We judge this approach to be adequately conservative and represents prudent construction practice.
b.
Any significant damage to pile butts during driving will be corrected by trirming pile butts, when necessary. This will be accomplished prior to the final driving phase to ensure that the maximum amount of harmer energy is applied to the piles during seating into the bearing layer or during redriving. This recuirement provides assurance that the assumptions made in the wave equation analysis are realized in the field.
Splices will not be permitted in the upper 20 feet of a pile except c.
I for a limited number of piles which may be driven deeper i
than anticipated.
In such instances, splices will be prohibited in the upper 20 feet of adjacent piles.
(Refer to our position on this matter transmitted to the licensee on May 16, 1980, in Item 362.07.) This will ensure that there is a minimun number of stress concentrations
. and regions susceptible to corrosion in the zone where the bending stresses in the piles due to lateral loading are significant.
d.
The licensee proposes performance requirement for the hamer and methods cf monitoring these to provide assurance that the hamer delivers its rated energy on each blow during driving of the piles.
The properties of the pile driving cushion will be monitored e.
to provide assurance that the reouirements for the cushion are satisfied, thereby ensuring that the maximum amount of hamer energy is transmitted to the piles.
f.
Piles driven on construction slopes will be monitored for lateral If displacement during driving (i.e., " walking" down the slope).
required, the licensee will use a restraining template. These field procedures will ensure that the piles are properly positioned in accordance with Item (a) above.
The contours of the top of the bearing layer which were determined during g.
the indicator pile program, will be revised continuously during placement of the production piles. We do not anticipate that this continuous revision will significantly change the contours. However, this procedure provides assurance that pile lengths which are anomalously long or short will be promptly detected, thereby permitting unusual pile penetration depths to be imediately assessed.
It will also ensure that the correct lengths of piles will be selected prior to driving, thereby satisfying the requirement discussed in Item (c) above.
. We find that the field installation requirements for the pile placerent contained in the various documents comprising the licensee's proposal, meet or exceed usual industry practices and provide assurance that the piles will be installed in a manner which will be consistert with the assumptions made in: (1) assessino the pile load capability; and (2) designing the foundation mat. On this basis, we find the aaditional proposed pile installation requirements discussed above, to be acceptable.
2.14 Inspection and Field Monitoring The licensee will provide a qualified pile inspector for each pile driving rig during construction. The qualifications, experience and duties of the licensee's pile inspector are contained in a separate 0A/0C manual prepared for the pile driving operation. We find the inspection precedures proposed by the licensee to be acceptable. Additionally, the on-site NRC inspection effort will be greater than that normally expended at this stage of construction to provide assurance that the pile placerent phase which is safe? i-related, is executed in an acceptable manner.
Since the capacity and performance of pile foundations are significantly dependent upon the installation procedures, the load capability of the piles cannot be definitively established until after it has been established that the piles have been satisfactorily installed. The installation program includes load tests on the production piles to confirm their load capability. For this reason, Region III of the Office of Inspection and Enforcerent (18E) will provide the enhanced inspection program mentioned above. Additionally, the Office of Fuclear Reactor Regulation (NRR) will institute an on-site ronitoring procram as part of its continuino review effort to ensure that the licensee's pile installation program is executed in an acceptable nanner.
8 9 The enhanced inspection program by 18E and the on-site ifRC monitoring prograr satisfies our commitment in the Bailly SER to " follow this iter during construction."
We also believe that on-site NRC inspection and monitoring programs are a proper irplementation of the inspection procedures anticipated by the Cormission in its Memorandum and Order of December 12, 1979 (Appendix C).
2.15 OA/0C For Pile Installation We hava reviewed the contractor's OA/CC marual for pile installation and find that it rust be revised to reflect the final driving criteria established by the NRC staff and agreed to by the licensee. The licensee has agreed to make the necessary modifications prior te driving any piles. We find this approach acceptable and will verify the acceptability of the ranual through our review and monitoring activities during the course of the pile driving program.
. 3.0 OUTSTAMDING ISSUES While there are several outstanding issues on which we have not completed our review, these ratters do not affect the load capability of the piles. Accordingly, they do not constitute a basis for any further restriction on pile driving. These items, including our bases for permitting pile driving prior to corpleting our review, are listed in the following sections.
3.1 Review of thi Pile Loads We have not completed our review of the licensee's calculated structural loads.
Normally, such a review would be properly deferred until the operating license stage of our review. However, we will review these calculated loads prior to the operating license stage since our approval of the foundation rat design is dependent on a comparison of the calculated pile loads with the load capability of the piles.
It should be noted that the pile load capability cannot be definitively established until ccmpletion of the load tests on the production piles discussed in Section 2.5 of this evaluation. Our position on this matter is that it would be premature at this time to review the licensee's calculated pile loads since corpletion of this review can be properly deferred until the pile load capability is determined.
Pile installation need not wait, however, since there are suitable methods which would provide additional foundation support capability if our subsequent review should indicate that the licensee's calculated loads are not sufficiently conservative. Furthermore, the pile load capability determined in the indicator pile program indicates that there is arple structural rarpin over the recuired factors cf safety.
(Refer to Section 2.3.3 of this evaluation). Accordingly,
. we find the proposed pile installation progran need not be deferred until we complete our review of the pile loads calculated by the licensee.
3.2 Foundatinns Outside the ffain Power Block We have not ccepleted our review of the foundations outside the rain power block.
However, the pile driving operation for the main power block area is a distinct construction activity physically separate from the fourdations for the exterior appurtenances. Specifically, the electrical conduits, the diesel generator tanks, the pumphouse structure and the water lines connecting the pumphouse to the main power block will be constructed as separate entities. The foundations for these exterior structures will have no impact on the driving of piles under the main power block structures. Moreover, any differential settlements which ray occur between these adjacent structures and the main power block can be readily accommodated by present state-of-the-art techniques. Accordingly, the foundation design of these exterior appurtenances does not affect our cerclusions regarding the pile fcundation under the main power block.
3.3 Long-Term Groundwater Considerations The groundwater considerations which influence the pile installation have been discussed above in Section 2.12 of this evalaution. While the long-tern groundwater effects are still under review, this does not impact the acceptability of the licensee's proposed pile driving program since none of the long-term groundwater effects will adversely ' affect the pile load capability.
3.4 Eackfilling Backfilling of the soil around the safety-related structures will be done after pile driving is ccmpleted. Since this operation will not affect our conclusions and findings on the acceptability of the pile placement prograr,
. the review of this item can be appropriately lef t until a later time.
3.5 Pile Group Capacity While we have not completed our review of pile group action, this matter can be readily resolved as discussed in Section 2.3.6 of this evaluation.
Accordingly, the resolution of this matter can be properly delayed until the individual pile' load capability is determined in the nanner outlined in Section 2.5 of this evaluation.
. 4.0 COPCLUSIONS We and our consultants have reviewed the licensee's proposed shorter piie installation program. We find that there is reasonable assurance that the principal engineering and architectural criteria established for the Bailly pile foundation in the SER issued in February 1972, will be ret by the proposed
' installation procram. On this basis, we find the pile installation prcgram proposed by HIPSCO to be acceptable.
Our conclusion that the proposed pile placement progran is acceptable does not extend to placement of concrete for the foundation mat since we ray require additional piles to be installed or adjustments ';de to the pile layout after our review of the entire pile placement program. Closure of this matter will be accomplished as discussed in Section 3.1 of this evaluation.
APPENDIX A I
'%'e UNITED STATES
- Eh NUCLEAR REGULATORY COMMISSION
! kN,, 4,%
I ADVISORY COMMITTEE ON REACTOR SAFEGUARDS Og' '
w Asmsetos. o. c. 2esss July 16, 1979 Hencrable Joseph M. Hendrie Chairman U. S. Nuclear Regulatory Comission Washington, DC 20555 SAILLY GENERATING STATION, NUCLEAR 1 S2 JECT:
Dear Dr. Hendrie:
12-14, 1979, the Advisory Committee en During its 231st meeting, July Reactor Safeguards reviewed the design of the pile foundations for the Sailly Generating Station, Nuclear 1, being constructed by the Northern B is matter was considered by an Indiana Public Service Company (NIPSCO).
ACES Subco.mittee at a meeting held in Portage, Indiana, near the site, on During its review, the Committee had the benefit of discus-July 9,1979.
siens with representatives and consultants of NIPSCO and of the NRC Staff.
Tne Comittee also had the benefit of the documents listed below and of statements received from members of the public.
In your letter dated June 8, 1979, you made the following request:
"The Comission recuests the Committee to identify and address the significance (if any) of the engineering and safety issues arising frem.use of the shorter pilings as opposed to the longer pilings.
In particular:
(1) is the use of shorter pilings a significant design change from the standpoint of engineering, and would it require significant alteration of other aspects of the design of the facility; (2) what differences, if any, would there be in the safety of the facility depending on whether longer er shorter pilings are used?"
l Tne Comittee heard reports en the experience to date relating to the driving cf piles at the site, including the exploratory driving of the longer piles to the till er rock, the extensive exploratory driving of the shorter piles into the interbedded sand and clay layer, and the varicus borings and pile de Committee also lead tests : hat have been made ever the past few years.
heard reports en analyses relating to the factors of safety to be provided against various loading combinations and to the expected settlements of the structures supported en piles.
\\
l O CfD 9'3 4-i L
Honorable Joseph M. Hendrie July 16,1979 The Committee has identified -only two potential safety issues arising fra the use of the shorter piles as opposed to the longer piles, and has con-cluded that neither of these will have any effect on the safety of the facility if the procedures proposed by NIPSCO or required by the NRC Staff are followed.
The first of these results from the fact that some of the exploratory longer piles were installed with the aid of high pressure water jets which resulted in disturbance of the soil (chiefly the sand) in the interbedded layer. "his disturbance is limited to only a small portion of the foundation area at four locations.
Unless remedial measures are taken, the shorter piles driven in these areas might be deficient in load-bearing capacity.
N!PSCO has proposed the use of " compaction piles" in the areas of disturbed soil to densify the disturbed soil so that it will be able to provide support equivalent to that in the other areas. The NRC Staff believes that this procedure is acceptable, and the Committee agrees, subject to compliance with the following procedures:
1.
Exploration by borings or by penetration devices to det. ermine the vertical and horizontal extent of the disturbed areas.
2..
Compaction of the disturbed material by driving compaction piles.
3.
Verification by borings or by penetration devices that all of the disturbed soil has been compacted.
4.
Derforming a compression load test on at least one production pile in each disturbed area to verify its load-carrying capacity and load-deformation charac-teristics.
NIPSCO has agreed to these procedures.
The second issue resulting from the use of the shorter piles is the potential settlement of the supported structures.
The settlement after construction would have been expected to be essentially :ere for the lenger pile foundation.
For the shorter piles, the settlement has been estimated by NIPSCO to be on the order of two inches.
Settlement of this magnitude is not unusual for a nuclear plant and would have no significance to safety.
The Committee has recommended to the NRC Staff, however, that the method of calculating the settlement 'be reviewed to assure that it has been dene conservatively.
l l
1 Honorable Joseph M. Hendrie July 16,1979 In addition, NIPSCO has proposed a program to measure.5ettlement at ntrnerous locations on the structures during operation of the nlant, and the NRC Staff has stated that such measurements will be required by the Technical Specifi-cations and that suitably conservative limits on per:tissible settlements will be established.
In view of these ec=mitments, the Cecmittee believes that potential settlements, even if greater than those now predicted, would not represent a hazard to the public.
The NRC Staff is continuing its review of the foundation design, and the Comittee believes that the remaining foundation-related issues, not related to the use of shorter piles, can be resolved by the Staff.
In direct response to the questions raised by your rec.uest, the ACRS believes that:
1.
7he use of shorter piling is not a significant design change from the standpoint of engineering.
2.
?ne use of shorter piling would not require significant alteration of other aspects of the desien of the facility.
3.
There will be no difference in the safety of the facility depending on whether longer or shorter pilings are used if the matters referred to above are treated as now proposed.
Sincerely, k
Max W. Carbon Chairman
References:
\\
1.
Preliminary Safety Analysis Report on Bailly Generating Station, Nuclear 1.
l 2.
Desien Analysis and Installation of Driven H-Piles Foundation, Report SL-3629, submitted on March 8, 1978.
3.
NIPSCO's Responses to NRC Staff Questions, submitted on July 14, 1976.
4.
Indicator Pile Program, submitted by NIPSCO to NRC on September 26, 1978.
l 5.
Supplementary Information on Driven 3-Pile Foundation, NIPSCO, December 4, 1978.
l 5.
Letter, D. B. Vassallo, NRC, to H. P. Lyle, NIPSCO, June 28, 1979.
7.
Sailly Generating Station, Nuclear 1 Construction Permit, May 1,1974.
l 9.
Request by the Porter County Chapter of the Izaak Walton League of America, Inc., February 27, 1979.
l 9.
Letter, S. M. Shorb, NIPSCO, to D. B. Vassallo, NRC, June 29, 1979.
I l
I l
APPENDIX B OCT 1 I 1930 i
Docket ?!o. 50-3G7 E!:CR/J:9U:t F02:
"u il. Carbon, Ch2irmn
- !visory Comitt:0 on Recctor Safeguards FRO:::
Janes P. Knight, l.ssistant Director for Co.mponents and Structures Engineering Division of Engineering, liRR SU3 JECT:
PILE I!!STid.LATIG:1 PLNIS FOR BAILLY GEf:ERATI:!G STATIO:1, ::UCLEAR 1 Part of the pile installation program proposed for the Dailly plant requires treat cnt of creas disturbed by previous construction activities (called preconstruction areas). The ACRS revie;2d the treat :nt for precoastruction creas proposed by the cpplic'nt, cnd your lett.'r dated July 16,1979 to J. ". I!andrie, Chair-2n, NRC, reported tFat ".CRS.~cund the applicant's proposed treatmnt of the preconstruction arc 2s to be acceptable, suSject to cr.plicace with four procciures.
The staff and its consultants find that intent of the required ACRS procedurcs can and will be followed; however, the specific details of how this will be
!:ne are subtly different from the netheds the ACRS ray have anticipated. A i
kscription of t!.is ".atter prepared by Dr. O. Thorpson, Hydroloqic and n ctechnical Engineering Branch, is presented in the attach. ent for the e
m infomation of the ACRS.
Janes P. Knight, Assistant Director for Cocoenents and Structures Engineering Division of Er;ineering Office of !:uclear Recctor Regulation
- ttachnent: As stated cc: 11. Dircks P. Crane H. Ocnton S. Goldberg E. Case J. Knight R. Vollner G. Lear H. Levin L. iie r
H. Thornburg F. Ri D. Eisenhut R. Sc R. Tedesco G. Z.e DUPLICATE DOCUMENT B. Youngblood D. Lynch Entire document previously entered into system under:
f0//Oh O //_3 ANO No. of s:
APPENDIX C Cite as 10 NRC 733 (1979)
CLI-79-11 UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION COMMISSIONERS:
John F. Ahearne, Chairman Victor Gilinsky Richard T. Kennedy Joseph M. Hendrie Peter A. Bradford in the Mattar of NORTHERN INDIANA PUBLIC Docket No. 50-367 SERVICE COMPANY (Bailly Generating Station, December 12,1979 Nuclear-1)
The Commission denies petitions requesting that the applicant's proposal to use shorter pilings than originally contempisted for the foundations of the Bailly Generating Station, Nuclear-1, be treated as a request for a construction permit amendment, with an attendant right to a heari.ig.
ATO311C ENERGY ACT: CONSTRUCTION PER311T A31END31ENTS Where the record indicates that the entire issue of pile design and placement has been left for resolution after the issuance of the construction permit, a decision by the licensee to use shorter pilings than projected at the construction permit hearing does not ofitself require a construction permit amendment. This is consistent with the reguh. tory scheme embodied in 10 CFR 50.35 and upheld by the Supreme Court in Power Reactor Development Corp. v. International Union of Electrical Workers. 367 U.S. 396 (196I).
ATO311C ENERGY ACT: OPERATING LICENSE REVIEW STATE Under ordinary circumstances, the operating license review stage is the appropriate forum for resol ing issues which at the construction permit stage were left for later resolution, or which arose after the issuance of the construction permit.
ATO.\\ llc ENERGY ACT: OPERATING LICENSES It is a fundamental precept of the Atomic Energy Act that possession of a construction permit is not a guarantee that the licensee will receive an 733
~
t which has received a l
operating license.The licensee bears the risk that a p ting license review 4
stag.
5.
MEMORANDUM AND ORDER f
the In November,1978, the Commission received two petitions, rom Steelworkers of State of Illinois et al' and from Local 1010 of the United t to the Th America, requesting the institution of a proceeding with respec y (NIPSCO)to use n here proposal of the Northern Indiana Public Service Companhe foundatio in the f
shorter pilings than originally contemplated or t ii 1974.
.m3 ft GeneratingStation, Nuclear-1,which receisedit i f ra Th ded itsissuance, inforn construction permit and in the evidentiary hearing that precebedrock or to lack i committed itself to installing pilings extending either to municated to the Comn glacial till just above bedrock; that NIPSCO's plan, com h l ial pes mi-NRC staff in March 1978, to install piles extending only to t e truction contr:.
lacustrine deposits, constituted in law and in fact a request for a c i
lving significant permi-permit amendment; and that the proposed change, nvo d ent could the of hazards considerations, required a hearing before such an amen m begin until the Atom be approved, and that pile installation could not legally ted. The petitions comm completion of judicial review of any approval gran longi-d eview by the NRC permi staff, and that pile installation had been halted sin i i
's staff itlear owing to its prior notifk k
should not participate in any way as a decisionma d the subject somet lieper t of det.tili matter" of the petitions.2 the Commission requested the commen sk d that the opera-On December 11, 1978, NIPSCO and the NRC staff on the petitions,in aIctter which as e "a rra submissions address certain specific questions:
l t to the permi
- l. What representations were made by the licensee with respec
/
for the I" thi of pilings for -the facility in its application l
mbmi construction permit and in the hearing record?
placement dein the pl l
- 2. To what extent is the licensec legally bound by representat I
attha i
the application for the construction perm t anunless uthorizing u hich W
different construction techniques?
ilings be p' ope l
- 3. Should the licensee's request for staff approval of shorter p i mendment? What accep-l L
treated as a request for a construction perm t a I
h 1
eof America.
P nF j
_' The other retaioners are the Porter County Chapter of the Izsak Walto d Profeoional People for the unres Inc.; Concerned Citizens Apmst Bailly Nuetear Site; Bainess anFederation. and th I y pe, Puhtu; Interest; the City ot G.n). InJbnx the take 5t:chipn Con %5s l
j indniduals.
i Petttions, p. l.fn.
standards are applied in determining when a construction permit amendment is required?
- 4. Does the shorter pilings proposal invohe significant hazards con-siderations? What are the applicable standards in making such a determination?
- 5. Should a hearing be ordered, either as a matter of right or Commission discretion? If the licensee's request is treated as an application for a construction permit amendment, is the availability of a hearing as of right dependent on a finding of signincant harards?'
The Commission also asked the NRC staff to describe its usual practices where an applicant proposes to deviate from the construction plan described in the application or the hearing record. The petitioners w ere insited to submit any further discussion of these points they might wish to proside.
The staff's response stressed the preliminary nature of the design information submitted at the construction permit stage, and the brevity and lack of specificity of the construction permit itself. It noted that the Commission's regulations specifically authorize the issuance of a construction permit even though not all technicalinformation has been supplied. The staff contrasted the preliminary design information supplied at the construction permit stage with the far more detailed review of final design informaticn at the operating license review stage. The staff obsened that as neither the Atomic Energy Act nor the Commission's regulations spell out the commitment made by, or the authority granted to, holders of construction permits, design changes proposed after issuance of a construction permit have long been treated on an adhoc basis by licensees and staff. The staff stated that it learns of design changes during construction through formal or informal notification by licensees; through the inspection and enforcement effort; and sometimes only when the facility is ready for operating license review.
Depending on the degree of signiGeance, a proposed change may receive detailed staff review, but more commonly, detailed review is deferred to the operating license review stage. Although a sufficiently major change could warrant a construction permit amendment,a resiew of 88 extant construction permits indicated that none had been amended for a design change, according to the staff's submission. Taken as a whole, the burden of the staff's submission was that the definitis e safety review which must take place before the plant can be licensed to operate, and the opportunity for a public hearing I
at that time, are the principal mechanism for resolving issues,such as this one,
.I which arise in the course of construction.
With regard to the specific issue presented by the licensee's short pilings proposal, the staff noted that while it had yet to find the proposal to be e
acceptable, the change was not such as to require a construction permit it amendment. The licensee,it said, had indicated a " preliminary intent" to drive pilings to bedrock or to glacial till, but the pile design explicitly remained 2
unresolved. The license application stated that "the final choice of the pile he type, capacity, and spacing will be determined based upon economic
^d considerations and further design studies,"and noted that test piles would be 735 P00R BRIGINAL
be obtained. The installed to verify that intended design capacities could il d made staff's safety review recognized the preliminary design of the p es an i
be no reference to pile length, referring instead to the fact that they were ff "high capacity, non-displacement piles" and were a designitem h is added).'The would follow afterissuanceoftheconstructionpermit(emp as i
i ss only discussion of piles in the hearing record occurred dur ng cro -
i that pile design examination of a NIPSCO consultant, who while in b di ither j
l dtests.
to bedrock or to glacial till, depending on the resu ii of process, too literal an interpretation should not be placed on the This construction permit authorizes the ap the construction permit that states:
principal architectural and engineering criteria and environ tion commitments set forth therein.*
Rather than signifying that the licensee is bound to conform to ev statement in the app'ication and the hearing record,5 the understood, according to th? staff, to bind the licensee to adhere to
" principal architectural and engineering criteria and environm i mendment is tion commitments." Contending that no construction perm t a
- rse, necessary,the staff observed that although case law on the subject wa h
pertinent decisions of the Licensing and Appeal Boards indi e of appropriate forum for considering design chan i
hearing before a licensing board.The staff submission conced Commis-engineering criteria" had never been defined with precision by the d
sion. A proposed rule, issued for public comm t
In general, NIPSCO's submission agreed with that of the necessary.*
j l d in the that the record indicated clearly that pilings were anissue to be reso ve f
il s) j course of construction. Indeed, the tests (invohing the driving o test p b
formed until that would permit resolution of the issue could notlegally e per l N!PSCO the construction permit was granted. The short pilings proposa.
l and contended, involved no departure from the principal architectura 8 Safety Esaluation Repoet (SE R). I 5 5.1.
- Construction Permit No. CPPR.104. raragraph 3C. fh tent to which a license 5 As we c Aplain below.we need not reach today the question o t e es di e we find that applicant is bound to representations in the application and the hearing re:or the issue of painp was left unrc>ohed at the construction perm hi t nce presiously emphawired -and underscored such the a 9761, a?2 sub nom. l'Erco v.
(North Anna Powcr Station. t%rs I and
). 4 NRC 480.456 (1 NRC. 571 Fad 139 (4th Cir.1978).* Proposed rule published April 16 POORORIGIN 31,19 7 0 ( 3 s F.R. s 317 ).
ed March
the engineering criteria. and thus required no construction permit amendment
- m.i<
and no hearing as of right. NIPSCO had not made a formal request. pursuant t. I,.
to 10 CFR 50.35(b), for approsal of the shorter pilings proposal,and beliesed
. u iti it questionable whether, in the absence of such a request, the Commission i t d.
could on its own determine to issue a construction permit amendment.
NIPSCO stressed that in pursuing the short pilings plan.it recogniecd that it I se would have to succeed in demonstrating at the operating license resiew stage citbri that the final design of the plant,and the facility as constructed, sati>itied the principal architectural and engineering criteria. N!PSCO contended that for s
, stap the Commission to order a hearing as a matter of discretion would repre>cnt a,n of abandonment of the Congressionally mandated two-stagelicensing process m favor of a continuous hearing process, thereby placing in doubt the certainly i.stity and value of every construction permit.
.ihibe Our consideration of the petitions, and the submission. of the staff and p otze.
licensee, led us to two preliminary conclusions. First, the Atomic Energy Act, its legislative history, and the Commission's regulations provided no clear
, egety guidance as to the type of design change which would require issuance of a
,iuld be construction permit amendment. Second, the filings before us did not to the illuminate a crucial question-the significance, from a technicalsiew point. of pntee.
the proposed use of shorter pilings.
. Iment is Accordingly, the Commission wrote to Chairman Carbon of the Adsisory
, sp.ir,e, Committee on Reactor Safeguards, on June 8,1979. We requested the that the Committee:
,,m se of
[T]o identify and address the significance (if any) of the engineering and iinteiim safety issues arising from use of the shorter pilings as opposed to the longer pilings. In particular: (1) is the use of shorter pilings a significant design
. tm.sl and change from the standpoint of engineering and would it require significant
. L'ommis.
alteration of other aspects of the design of the facility;(2) what difference if
.priosed.
any, would there be in the safety of the facility depending on whether udv were longer or shorter pilings are usedT Chairman Carbon designated a subcommittee of the ACRS to consider
'It stressed these questions. The subcommittee retained consultants with special expertise acdin the the ar as under consideration, and on July 9, conducted a public meeting in tea piles)
- tage, Indiana, close to the Bailly site, at which representatives of the med until part.es and members of the public presented views. On July 12,1979, the NIPSCO subcommittee met in an open session at which Committee members asked tm.d and numerous questions as to the bases for those findings. The following day, the full Committee met, again in open session, to compose a letter replying to the Commission's June 8 request.
,,,,,,i w The Committee's letter, dated July 16,1979, is attached to this Order as
,m una: hat Appendix A. It described the data base for the ACRS' judgments regarding
.no.a..ian has the short pilings plan, including:
he a"iv'taad
" Reports on the experience to date relating to the driving of the longer
'"",'.).')).'[
piles to the till or rock, the extensive exploratory driving of the shorter piles into the interbedded sand and clay layer,and the various borings and n..
ro uin-pile load tests that have been made over the past few years. The Committee 737 P00RORBM
I be also heard reports on analyses relating to the factors of safety to d
provided against various loading combinations and to the expe settlements of the structures supported on piles."
The Committee stated that it had "identiGed only two potential d to the longer piles, inues arising from the use of the shorter piles as oppose f
fthe and hed concluded that neither of these uillha il in the are followed." The first of these related to disturbance o high interbedded layer in four locations where longer piles were drive d found pressure water jets. There NIPSCO had proposed. and the s i
il s " The acceptable, a plan to densify the softened soil w i
il s; measuring the extent of the disturbed soil before installing compact determining that compaction of the disturb He second of the two issues identified by the ACRS was the loads.
h as settlement of the supported structures. The A ll h e
ult in of starter pilings could be expected, according to the licensee, to res h
ff view settlement of about two inches. The ACRS recommend l d d that the calculations of the licensee to conGrm their accuracy,but conc u e if they potential settlements would not represent a hazard to the pu exceeded current predictions.The ACRS concluded its letter w pc sed by the Commission, stating its belief that:1. "H
- 2. The use of shorter piling would not require signiGeant standpoint of engineering.
other aspects of the design of the facility.
i
- 3. Here will be no difference in the safety of the facility depe f
d above whetherlonger or shorter pilings are used if the mattersre erre are treated as now proposed."
j On July 25,1979, the Commission issued an order inviting an f
h provide comments on the ACRS letter. Comments were re staff, the licensee, and the petitioners.The staff and the li i
ACRS solicited the expert advice of consultants and the views h ACRS and the public before reaching its conclusions. Both pointed to t e letter as supporting their view that the s j
i J
l required no construction permit amendment.The peti 5
proside a thing meaningful response" to the Commission's rcquest, as there was t
the which "even purports to provide the reasoning. the basis, the supp ii specine justification" for its "conclusory answers" to the Cemm ss on s
) - blUbff@g.,
QJ n
l 738 m
questions. The ACRS letter, according to the petitioner >, is simply of no value'in resp 3nding to the Commission's request, and siolates the duties of the ACRS as enumerated in l'ermont Yankee Nuclear Poner Corp. v.
NRDC. 435 US 519,556 (1978).
It is not necessary to rehearse here each of the petitioner >' objections to the ACRS letter, but some examp'e> may be illustratise. With reference to the ACRS' approval of the use of compaction piles to densif> disturbed > oil, t
petitioners state:
The AC RS conclusion concerning the issue is completely circular and. in 3
i effect. no conclusion at all. The ACRS states that it agrees that NIPSCO's proposal to use " compaction piles"is an acceptab!c procedure, subject to compliance with four procedures, one of which is compaction of the disturbed material by drising compaction piles. The other three te procedures similarly are described in terms of their sucec>s.'
As is unmistakable from the text of the letter, howeser. the ACRS was 3,
recommending an orderly four-step procedure: first. testing the soil; then installing the compaction piles; then testing the compacted soil; and finally,
,A testing the installed piles'c1pacity to bear loads. There is nothing whatsoeser 3,
about these procedures or the Committee's description of them that can in reasonably be called " circular.'
gw Again, petitioners contend 8 that the ACRS should have waited for the submission of the consultants' written report before writing its letter to the h.a Commiuion. The ACRS, which meets only once a month, was originally hes asked by the Commission to submit its views by June 30,1979. By writing its
,gn,.
reply to the Commission on the basis of what it learned from the subcommittee and its consultants in oral presentations, rather than awaiting the the reduction of those views to writing.' the Committee avoided an unnecessary delay of a month, n et With regard to petitioners
- assertion that the ACRS vic'ated its duties as spe!!cd out in Vermont Yankec reference to the Court's opinion in that case 4 en indicates otherwise:
. tsm e
[T]he legislatise history shows that.. its [the ACRS report's] main function [was] that of providing techni:al advice from a body of experts uniquely qualified to provide assistance. [ Citations omitted]. The basic
. gy i,,
Ethe information to be conseyed to the publicis..the ACRS's position,and reasons therefore, with respect to the safety of a proposed nuclear reactor.
h the Of equal significance is the fact that the ACRS was not obfuscating its
.nti,,
findings. 435 U.S. 519,556.
g
'Here, the ACRS provided its views on the technicalissues it was asked to ed no address, and did so with clarity and conciseness. The 120-page transcript of g.gc,.
the ACRS meeting on July 12, which petitioners cite numerous times in their
,ide a
Pctitioner's Comments on the ACR5' July 16.1979 Letter," p. 4 othin;-
- Petitioner's Comments on the ACRS' Joly I6,1979 Letter," p. 6.
' or the e The consultants
- sritten statement. shich appears as AppcMit B to this Or&r. is fully pecilie consistent with their orat report to the ACRS.
739 P00R 0 M
i
.e l
t i
i comments, contains the fuller explication of the bases for the Com In short, petitioners' assertions with respect to the ACRS letter do n judgments.
inchide,in our view, substantive grounds for faulting its technicaljudgm We therefore accept the ACRS's judgment that the proposal to use
{
pilings is not significant as a matter of engineering and wil i
f i significant alteration of other facility design a i
nd-then becomes whether, given this judgment, a construction perm t ame ment is rcquired. We believe that, for the reasons described below,th The license application indicated that piles would be driven into is no.
d that till or to bedrock (PSAR Section 2.5.4.3.1), but also repeatedly stresse fmal decisions with respect to " pile type, capacity, and spacing" determined only after a test pile program and further design stu 2.5.4.3.3). The PS AR makes clear that the objective of pile inst f
assure that the " intended design capacities can be attained by a h
of two. (Section 2.5.4.3.3). In other words, the oserriding necessity di the pilings do the job of supporting the plant,but untiltest piles were i
and the applicant could not legally drive tes capacity, and the optimum design of the fo d
stated simply (at Section 5.5.1) that the design of the foundation on the use of high capacity non-displacement piles," adding,"we this item during construction."The only discussion of pile d particularly instructive. In the following ex the Commission), cross-examined a consultant to the applicants:
Q. Now, as I understand your testimony, b pilings,is that right?
A. Yes, sir.
Q. And how deep do those pilings go?
A. Well, that wuuld be predicated on a pile either be founded in the till directly above the rock or in the bed depending upon the pile test thatis run and whether you physically drive piles into the rock. (TR 2141).
piling had not been determined, and would not be decide results of the pile test had been obtained.
Q. So that the design for the piling has not been determin A. Yes, sir, that's correct.
740 WWWh e-em-M D P s-W.W a
.b
v er Taken as a whole this passage in our view emphasires the scry pieliminary nature of all aspects of the foundation pilings. The witness' immediate respon>e to the only specine question on pile depth was that it would be
,[,
determined after a pile test. He added that he " anticipated" that the piles
.']
would be driven to bedrock or glacial till. But" anticipation"of what the pile test would indicate with regard to soil density is hatdiv the same as a
~
~
commitment to a particular result. This mu3t also be read in eonjunction with the fact that the criticalissues of pile design and spacing had explicitly been
"[
left for later resolution. In our siew, a fair reading of the entire record is that
"'],
the whole issue of pile design-including type of pile, spacing, and depth-was left unresolved at the time of construction permit issuance.
gg it is worth reiterating that the Commission regulations do not require that every safety-related issue be resolved prior to the issuance of a construction gg y g,,
permit. Under 10 CFR 50.35(a), the Commission may issue a construction
'g;,,n permit esen if full technical information is lacking, provided that; the
' is to applicant has described the proposed design of the facility," including but not jq limited to, the principal architectural and engineering criteria"; the issue can sth.o be left for later resolution, and necessary research and development can and will be conducted; and there is therefore reasonable assurance that the issue
.en d in will be resolved satisfactorily by the time construction is complete.'
yn,,
This regulation and the approach it embodies were upheld by the Supreme
'j-Court in Power Reactor Development Corp. v. International Union of Electrical Workcrs, 367 U.S. 396 (196 !). The corollary of this provision is that
' I
- the grant of a construction permit does not, absent a speciGe finding by the
'baseil Commission at the licensee's request," constitute Commission approval of the I# "
safety of any design features or specification." 10 CFR 50.35(b).
- , g, The issue of pilings was not contested in the hearing, and there w o ounsel therefore no occasion for the Licensing Board to specify that this was anissue
, Nfore which was being left for later resolution pursuant to 10 CFR 50.35(a).
' 10 CFR 50.35(a) reads in full:
Igs. tIW -
When an applicant has not supp!!ed initially all of the technicalinformation required to rted on complete the application and support the issuance of a construction permit which approses all proposed design features, the Commission may issue a construction permit if the Commission finds that (1) the applicant has described the proposed design of the facility, inctuding, but not limited to the principal architectural and engineering criteri* for the design, and has identified therein the major features or components incorporated therein for
-Dame 4 the protection of the health and safety of the public;(2) such further technical or design that will information as may be required to complete the safety analy sis, and whieh can reasonably be bedroe\\,
left for later consideration, will be supplied in the final safety anal} sis report;(3) safety features or components,if any, w hich require research and des elopment hase been describeJ ggy by the applicant and the applicant hasidentified,and there will be conducted,a research and desetopment program reasonably designed to resolve any safety questions associated with gn for the such features or components; and that (4) on the basis of the foregoing, there is reasonable until the assurance that (i) such safety questions will be satisfactorily resolsed at or before the latest date stated in the application for completion of construction of the proposed facihty,and (ii) taking into considi: ration the site criteria contained in Part 100 of thn chapter,the proposed
.i3 point?
facility can be constructed and operated at the proposed location without undue tisk to the health and safety of the public.
741 100RORNM
v
-o Reference to the regulation is instructise howescr; in our view,it shows that be the present case falls squarely within the category criteria" have been described: the piles are to be "high capacity" and "non-displacement." Second, the further technical and design information j
i to complete the safety analysis can reasonably be left for later considerat o indeed,it can only be resolved after tests for which the lic2nsee must have a construction permit. Third, a research program,invohir.g tt e sinking of tes i
piles, will be conducted to supply the needed information. Based on considerations, we believe that there is reasonable assurance that the outstanding safety questions can be resobed, and resched early in the i
construction process. We therefore see no reason to alter our view, ref be the original issuance of the cons'.ruction permit, that the facility can constructed and operated without undue risk to the health and safety of public. Our conclusion in this regard is in large part grounded on If the Joint Intervenors 1.ad in fact contested the issue of pilings during the the ACRS.
hearing, and if the issue had been designated for later resolution under CFR 50.35(a), their first opportunity for a hearing on the merits of the particular pilings design selected by the applicant would indisputab hearing available at the operating license resiew stage. Though the issue not specifically so designated, we beliese that the operating license i
nesertheless the appropriate forum for a hearing on the licensee's pil ng proposal.To recapitulate, we believe that the short pilings plan is less a ch an earlier plan than it is a proposed resolution of an area consciously-a appropriately-left for later determination. As such it requires no constr f right on tion permit amendment, nor the hearing that is ava the strictly legal question to the important underlying issue of substance-h whether the short pilings plan, because of safety or other issues raised,ou to be the subject of a discretionary hearing at this time favors a two-stage process: a mandatory hearing before construction can begin, and a second hearing, available upon request, before the c plant can be operated. At that second hearing,un resolution, or w hich arose after the issuance of the construction permit.
hingto view the record before us,especially the views of the ACRS,we find not suggest that there would be any benefit in injecting an interim pub It will undoubtedly be objected that a serious error in the design of the at this time.
pilings could, as a practical matter, be uncorrectable if detected o plantis completed. This may well be so. lioweve Reactor. 367 U.S. 396 mpra, that possession of a construction permit 742 P00R ORIGW.
.o.
l guarantee that the licensee will recei',e an operating license. If the utility's pilings proposal-or any other aspect of the facility-fails to pass muster at the operating resiew stage, the plant will simply not be allowed to operate.
This risk is borne by the licensee. As the D.C. Circuit recently said (in a case involving this same facility and most of the same principals), Porter County Chapter of the 1:aak Walton League v. NRC. -F.2d-(Sept. 6,1979):
It is not the public, but the utility, that must bear the risk that safety questions it projects will be resolved in good time, may eventually prove intractable and lead to the denial of the operating license. See p. 740.
In holding that the proper occasion for a hearing on this pilings proposatisat the operating license review stage, we are emphatically not saying that the issue of pilings can or will be ignored until that time. As we have seen. the staff is reviewing the issue now and will continue to do so during construction.
Should the staff at any point determine, either on its own initiative or in response to a request under 10 CFR 2.206, that substantial health and safety issues hase been raised with respe:t to the activities authorized by the construction permit,it can in its discretion institute proceedings pursuant to 10 CFR 2.202, or order the suspension of construction.
Finally, it should be reiterated that our decision today does not in any sense whatsoever create a risk to pub ic health and safety. As the Court of Appeals observed in Porter County, -F.2d, supra:
In the case of a construction permit for a nuclear power plant, however, permitting continued construction of the plant despite unresolved safety questions does not ofitself pose any danger to the public health and safety.
Before the license is granted to operate the plant there will be adjudication proceedings. Any interested party may request a hearing. In such an operating license proceeding unresolved safety questions will be con-sidered. A positive finding of reasonable assurance of safety is a prerequisite to issuance of the operating license. See p. 740 supra.
It is so ORDERED.
t For the Commission t
S AMUEL J. CHILK n
d.
- Secretary of the Commission
- )
Dated at Washington, D.C.
'e this 12th day of December,1979.
to -
11' he he
- pt ur st a 7'3
?DDRDGNAL
.