ML20041E665

Forwards Responses to Structural Engineering Branch Series 220 820211 Requests for Addl Info Re Ability of Seismic Category I Structures to Withstand Various Pressure Loads. Responses to Listed Requests Will Be Submitted by 820312

ML20041E665
Person / Time
Site:	Seabrook
Issue date:	03/05/1982
From:	Devincentis J YANKEE ATOMIC ELECTRIC CO.
To:	Maraglia F Office of Nuclear Reactor Regulation
References
RTR-NUREG-CR-0098, RTR-NUREG-CR-98, RTR-REGGD-01.092, RTR-REGGD-01.136, RTR-REGGD-01.142, RTR-REGGD-1.092, RTR-REGGD-1.136, RTR-REGGD-1.142 SBN-220, NUDOCS 8203110224
Download: ML20041E665 (51)

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{{#Wiki_filter:~Y t puBLIC SERVICE SEABROOK STATION a Engineering Office: Companyof New Hampshir e 1671 Worcester Road Frominchom, Mossochusetts 01701 (617) - G72 - 8100 t March 5, 1982 SBN-220 T.F. B 7.1.2 C Af O %OL% ~ United States Nuclear Regulatory Commission Washi ng ton, D.C. 20555 g Attention: Mr. Frank J. Miraglia, Chief Licensing Branch #3 Division of Licensing

References:

(a) Construction Permits CPPR-135 and CPPR-136, Docket Nos. 50-443 and 50-444 (b) USNRC Letter, dated February 11, 1982, " Requests for Additional Information", F. J. Miraglia to W. C. Tallman

Subject:

Response to 220 Series RAls (Structural Engineering Branch)

Dear Sir:

We have attached responses to the subject RAIs which you transmitted in Reference (b), with the following exceptions: 220.14 220.15 220.36 Responses (or a schedule for response) tc the above RAIs will be provided by March 12, 1982. The response to RAI 220.34 will be the subject of a structural design audit conducted by your Structural Engineering Branch during the week of March 29, 1982; therefore, a response is not included with this letter. Very truly yours, YANKEE ATOMIC ELECTRIC COMPANY (g J. DeVincentis Project Manager c\\ o JDV:ALL:pmc \\ Attachments 8203110224 820305 PDR ADOCK 05000443 A PDR m

r SB 1 & 2 FSAR RAI 220.6 (3.3.1) Se ction 3.3.1.2.a of the FSAR states a formula p = 0.0256 (GV)2C The constant 0.0256 in the above formula should be 0.00256 per ASCE.p. Confirm that the correct constant is used in the design and correct the FSAR or justify the deviation.

RESPONSE

The formula as given in the FSAR is incorrect, however the correct constant, 0.00256, was used in design. This typographical error has been corrected. pm - - -m-- / I l I l l l ....e ~ .}

(.ML M S. lo\\ SB 1 & 2 FSAR s 3.3 WIND AND TORNADO LOADINGS l 3.3.1 . Wind Loadings The design of seismic Category I structures for normal wind loading is based on two criteria: (1) ASCE Paper No. 3269, " Wind Forces on Structures", j Reference 1 and (2) ANSI A58.1-1972, " Building Code Requirements for Design l Loads in Buildings and Other Structures", Reference 2. The ASCE paper is used to derive the wind loading for the containment enclosure building, whereas the ANSI guideline is used for wind loading on all other seismic Category I structures. 3.3.1.1 Design Wind Velocity l The design wind velocity at 30 feet above ground for the 100 year period of recurrence is 110 mph (See Subsection 2.3.1). i ASCE - The vertical wind velocity profile is interpolated from a. Table 1(b) of Reference 1. A gust factor of 1.1 is used in deriving wind londing based on guidelines' presented in Reference 1. b. ANSI - The vertical velocity profile and applicable gust factors are included in the velocity pressure profiles discussed in Subsection 3.3.1.2 (b). (' 3.3.1.2 Determination of Applied Forces Wind loads are applied as uniform static loads on the horizontal and vertical projected areas of the structure walls and roof. Shielding effects provided by other structures are neglected unless a portion of th'e exposed surface is immediate1 adjacent to another structureT^~0nly dead loads are considered-y in resisting uplift. ASCE - The' design wind velocities are converted to wind pressures a. by the following formula: t 4 002 % 1 p = A46% (GV)2 Cp where: p = design wind pressure (psf) C = gust factor i V = wind velocity (mph) Cp = pressure coefficient (Table 4, Reference 1) The vertical profile of wind pressure on the containment enclosure building is summarized in Table 3.3-1. The distribution of effective pressure coefficients, (Cp), for cylindrical and spherical structures is shown on Figure 3.3-1. 's 3.3-1 1 ,-_--,v-- r ~_, .m. ..m.-.

f SB 1 & 2 FSAR RAI 220.7 (3.3.1) Section 3.3.1.2.b of the FSAR states a formula, p = qCp + qMC i. According to ANSI-A58.1-1972, this formula should be p = qc qnC i, knplainthe p p discrepancy or implement the correct equation in your design and revise the FSAR.

RESPONSE

The formula has been incorrectly stated in the FSAR. The FSAR will be revised to correct the noted discrepancy. A 9 M^ m l i I l i l l i i l l 1 f .._.m..

~ i ( fh f, TA-0. = SB 1 & 2 FSAR b. ANSI - The ef fective velocity pressure vertical profile, including factors for structures (qr), parts of structures (q ), and p gust internal pressure (qs) are taken from Tables 5, 6 and 12 (Exposure C) respectively of Reference 2. The ef fective velocity pressures are summarized in Table 3.3-2. The average pressure acting on a structural element is as follows: p =qC qg C i p p where: = average wind pressure (psf) p whichever is appropriate q = gr or qp C = external pressure coefficient pqn = internal velocity pressure C t = internal pressure coefficient p Load combinations involving normal wind (discussed in Subsections 3.8.4.3 and 3.8.5.3) do not control the design of seismic Category I structures. i 3.3.2 Tornado Loadings 3.3.2.1 Applicable Design Parameters Tornado wind loads on seismic Category I structures are based on a ) a. single vortex tornado model which results in a maximum tangential velocity of 290 mph and a maximum translational velocity of 70 mph. The total maximum wind velocity is 360 mph assumed constant with respect to height. The pressure differential is 3 psi at a race of 2 psi /second. See Subsection 2.3.1.2. for a discussion of thesdesign basis tornado parameters. v-mw-b. Protection of equipment and systems located in the structures listed in paragraph c. below, is accomplished by the use of protective barriers consisting of dampers complete with the necessary accessories and instrumentation. These dampers are provided at all inlet openings located in the exterior walls of the structures which provide outdoor air for the plant HVAC systems. These dampers are also provided at the openings in the exterior walls of the structures, through which air is exhausted from the vari.ius plant IIVAC systems to the outside atmosphere. 'The dampers automatically close to avoid damage which could be caused by tornado induced depressurization within the structures to the systems and components located inside the structures. 3.3-2

SB 1 & 2 FSAR RAI 220.8 (3.3.2) In Section 3.3.2.2 of the FSAR, it is mentioned that maximum velocity pressure 2 is given by the formula qmax = 0.00256V. Confirm that the velocity pressure is assumed to be constant with height, and that maximum velocity pressure applies at the radius of the tornado funnel at which the maximum velocity occurs. If not, then clearly mention your assumptions. Also, clarify how you have considered the variation of tangential velocity with the radial distance from the center of the tornado core.

RESPONSE

Velocity pressure is assumed to be constant with height. Maximum velocity pressure is based on the maximum tornado ' wind velocit/and is assumed to occur at the radius of the tornado funnel at which the maximum velocity occurs. Variation of tangential velocity with radio distance from the tornado core is determined as follows: r Ve=7xVt max for 0 < r< rm. m m Ve= xV for r < r < r e max m 75 where t tangential velocity at radius r V = e maximum tangential velocity (290 mph) V = radius from centerline of tornado r = y~ r, radius of maximum-tangential.. velocity (150 ft) = ~~ < radius at which tangential velocity equals 75 mph (580 ft) r = 75 l l l l I l

SB 1 & 2 FSAR RAI 220.9 (3.4.2) The methods by which the dynamic effects of design basis flood are applied to safety related structures are not clearly mentioned in FSAR. Since the flood level is above the proposed plant grade, such dynamic loads and their determination is an important concern to NRC staff. SRP Section 3.4.2 Subsection II.3 delineates an acceptable method. Clearly mention the methods and procedures used, stating whether or not you meet the SRP criteria.

RESPONSE

Dynamic effects of the design basis flood were considered, but found to be negligible. As stated in the FSAR (Subsections 2.4.5.3 and 3.4.1), the maximum depth of stillwater is 0.6 feet above plant grade, and the maximum wave runup in local regions is 1.8 feet above plant grade. Any dynamic effects produced by these occurrences will be small and, due to the relatively large masses of the reinforced concrete structures, can be neglected. Note, however, that hydrostatic effects of the flood are considered in the design of stru6tures with regard to buoyancy and associated behavior. .w a,. v,, _ %r sz e- ~ t i l 's l l i l l

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SB 1 & 2 FSAR RAI 220.10 (3.5.3) Section 3.5.1.4 of the FSAR states that tornado missile spectrum used is shown in Table 3.5-11 of FSAR and is the same as MISSILE SPECTRUM of the SRP Section 3.5.1.4 Rev. O. The current staff position for tornado missile spectrum is outlined in Table 2 of the SRP Section 3.5.3 (Attachment 1). Please implement the current staf f position, or submit your justification for the deviation.

RESPONSE

Rev. 1 of SRP 3.5.3, July 1981, states: "The tornado missile spectrum for which Ta' ale 1 concrete requirements are adequate, is shown in Table 2. Tornado missiles and other types of missiles are specified in accordance with SRP Section 3.5.1". The spectrum shown in Table 2 is identified as Spectrum II in SRP 3.5.1.4 Rev. 2, July 1981. It is described in NRC question 220.05 as the " current staff position". Review of SRP 3.5.1.4 Rev. 2, July 1981, indicates that: " Applicants who were required at the construction permit stage to design to one of the missile spectra (A or B) of the November 24, 1975 version of this SRP section (or a review modification such as 24" vertical and 21" horizontal wall thickness commitment in Region I), shall have the option at the OL stage of showing conformance with either their original commitment or Rev. 2 (same as Rev.1) to this SRP section. Partial compliance with each is not acceptable". The identified Spectrum A is the spectrum shown in Table 3.5-11 of the FSAR. Compliance with the current NRC staff position is satisfied. .x;maa,-, ..m

SB 1 & 2 = FSAR RAI 220.11 (3.5.3) Section 3.5.1.3.C.1 of the FSAR states that perforation of the containment is not considered to be unacceptable damage, and containment liner is expected to prevent secondary missiles from entering the containment. FSAR Section 3.5.3.1.b also says that no steel barriers were designed. Clarify how you have ensured that the integrity of liner plate will not be impaired.

RESPONSE

With respect to insuring the integrity of the liner plate, Regulatory Guide 1.117, Tornado Design Classification, states that, "The primary containment need not necessarily maintain its leak-tight integrity (after a tornado-missile strike)." This loss in the liner integrity is permissible only on the basis that no missiles, primary or secondary, can actually enter the containment itself and cause damage to any of the safety-related systems. This criterion is also applicable in principle to turbine missiles (Regulatory Guide 1.115). Those turbine missiles, identified as possessing sufficient energy to penetrate the containment shell have been evaluated as part of a probabilisticstudy which has determined that these missiles fall into an established category of acceptable risk (See FSAR Section 3.5.1.3) and, as such, are beyond the scope of this discussion. The remaining turbine missiles do not possess sufficient energy to penetrate the containment shell but some may possess sufficient energy to cause dislodgement of concrete on the inside face, local to the impact area. In this event the liner plate will serve to contain these concrete fragments, l thus preventing any secondary missiles from entering the containment. Under L_ e no, circumstances.has the.. liner-plate.been. designed to function _as a. barrier;, % _ .e, l however, under the above situation the presence of the liner will serve to confine the spalled concrete. l l l l l

4 i I SB 1 & 2 FSAR RAI 220.12 (3.7(B).1.2)- Discuss, whether or not, the artificial time histories used in your analyses are base-line corrected. If not, discuss the implications and justify the use of such time histories.

RESPONSE

All artificial time histories used in the analyses are base-line corrected. 2 I e t f i i e MKT ~, o Ree w+ ,,,y p 1 t l l l t I i i I s -_s n y y, p- -- -~ -- --,-.r- ,,m,, q--m-+-- -,3e. e -m p -w-- 9-wr

= RAI 220.13 (3.7(B).l.3) = As noted in this section, R. C. 1.61, Section C.3 requires that damping value s, lower than those specified in Table 3.7.1, should be used if the maximum combined stresst s due to static, seismic, and other dynamic loading are significantly lower than the yield stress and 1/2 yeild stress for SSE and 1/2 SSE (or OBE), respectively. Indicate whether j damping values used in the analysis are in compliance with this { requirement. Also, indicate your procedure to assure such compliance. t in addition, if you had to use lower damping values, provide the values -used for the staff's review. Re sponse Observations and measurements have shown that the damping levels may vary over a significant ra nge. Convergence problem can be encountered when attempting to match damping values with calculated stresses. Table 220.13-1 compares the damping values used for the analysis as set forth in the USNRC R. G. 1.61 with those recommended in NUREG/CR-0098. The upper values of the pair of values in the NUREG/CR-0098 column are considered to be average or slightly above average values, and the lower values are considered to be nearly lower bounds and are therefore highly conservative. The damping values given in R. G. 1.61 and used in analysis and design of structures compare close to the lower values of the NUREG/CR-0098 and therefore are considered to be conservative and suitable for design. i

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SB 1 & 2 FSAR TABLE 220.13-1 DAMPING VALUES (Percent of Critical Damping) ~ Operating Basis Safe Shutdown Earthquake Earthquake NUREC/CR-0098 NUREG/CR-0098 Structure or Component R.G. 1.61 Reconsnended R.C. 1.61 Recommended Vital Piping 1 1 to 2 2 2 to 3 Welded Steel Structures 2 2 to 3 4 5 to 7 Bolted Steel Structures 4 5 to 7 7 10 to 15 Prestressed Concrete 2 2 to 3 5 5 to 7 Structures Reinforced Concrete 4 3 to 5 7 7 to 10 Structures h~ t_ i i i i

SB 1 & 2 FSAR RAI 220.16 (3.7(B).2.1) (3.7(B).2.4) Describe your procedure to compute dynamic lateral earth pressure and hydrodynamic groundwater pressure during seismic event.

RESPONSE

The dynamic earth pressure increment for non-rigid walls is based on the acceptable industry practice (i.e., as per the recommendation by H.B. Seed and R.V. Whitman in their paper, " Design of Earth Retaining Structures for Dynamic Loads", Spacialty Conference on Lateral Stress in the Crcund and Design of Earth Retaining Structures, Soil Mechanics and Foundation Division, ASCE, 1970). The dynamic earth pressure increment for rigid walls is proportional to the co'ef fic.ents of dynamic and passive earth pressure, the density of the i backfili and the height of the vall. Also, if there is a fixed or permanent surcharge in the area adjacent to the wall, it was also considered in computing the dynamic earth pressure due to earthquake. There are no hydrodynamic effects due to groundwater because there are no structures exposed to free groundwater. The only dynamic effect produced by the presence of groundwater is an increase in dynamic lateral soil pressure resulting from an increase in density of backfill material from that of the moist condition to that of the saturated condition. Maximum dynamic earth pressure is, therefore, the sum of normal static earth pressure, dynamic surcharge ef fect (if any) and dynamic soil effect, as illustrated in Figures 220.16-1 and 220.16-2 for non-rigid and rigid walls, respectively. Note that these figures also show the development cf the F" static components of lateral earth pressure. si - p- - - - -- l 1 1 l l

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i SB 1&2 FSAR RAI 220.17 (3.7(B).2.4) In this section, you have stated that embedment effects are neglected in the soil-structure interaction analysis for Category I manholes. Discuss the implications and conservatism of this assumption. Also, discuss the values of the soil p parameters used in your analysis. Specifically, address the variation of parameters and how the radiation damping effects were accounted for. Indicate and discuss, whether or nor, the seismic input motion at the base of the soil-spring was different from the one described in Section 3.7.1.

RESPONSE

The analysis objective was to arrive at maximum seismic loading for the design of manholes. i The effect of embedment is to increase the soil spring stiffness thus increasing the natural frequency of the system resulting in reduced seismic design value. Hence, it was conservatively assumed to neglect embedment effect. To reduce amplification properties of the soil between the ground surface and the rock, the backfill was well compacted through the use of vibratory compaction equipment. The engineering properties of the backfill mat & rial is controlled by controlling the placement requirement and material characteristics. The soil property given in the FSAR Section 3.7(B).1.4 is used for determining soil stiffness. The above conservative assumption combined with lower system damping values ~.of.7 percent for SSE and_4_ percent _for OBE causes seismic load,,in excessg the actual value. The design ground resp >n'se spectra discussed in Section 3.7(B).1.1 were used as input for the analysis. T t

SB 1 & 2 FSAR RAI 220.18 (3.7(B).2.5) The frequency increments (Table 3.7(B)-21 of FSAR) used for' calculating floor response spectra are larger than those suggested in SRP Section 3.7.1. Discuss the implications of these differences and justify your frequency intervals.

RESPONSE

The frequency increments used for calculating floor response spectra are based on Table N-1226-1 of ASME Boiler and Pressure Vessel Code, Section III, Division 1, Nuclear Power Plant Components, 1980 Edition, App'endix N, ' Dynamic Analysis Methods'. The natural frequencies of the structures were included in computing The table shown in SRP Section 3.7.1 is for meeting the response spectra. spectra-enveloping requirements of the design time history, where the frequency intervals are required to be smaller. O b

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= 220.19 When seismic Category I piping is directly connected to the ( 3. 7( B ). 3.13 ) ' non-seismic Category I piping, confirm that the attached non-seismic Category I piping, up to the first anchor beyond the interface, are designed in a manner that earthquake of SSE intensity will not cause f ailure of seismic Category I piping. -

RESPONSE

To assure that an earthquake of SSE intensity will not result in f ailure of seismic Category I piping, the model would i include the non-seismic Category I piping up to a boundary I res traint (defined as a set of one or more restraints or i anchor). Typical functions and locations of these restraints are shown in Figure 220.19-1. In Case 1, moments and forces f introduced by the non-seismic piping are reacted through the six degree-of-f reedom restraint as shown. In Case 2, moments are reacted by couples between pairs of restraints which limit motion in the indicated directions. These boundary i restraints are designed to withstand the plastic capability of the contiguous piping. The structural integrity of the non-seismic Category I piping is assured by compliance to the indicated stress limits. Class 2 or 3 piping must satisfy the limits of ASNE III, NC-3600 or ND-3600. Pipes and l supports in the shaded regions are included in the mathematical model of the seismic Category I piping and are subjected the SSE load s. Non-seismic piping beyond the boundary restraints satisfy the limits of B31.1. Loading conditions and stress limits for all pipe classifications are summarized in Subsection 3.9.3. i 1 Y [ y " *. g 4e - g ) l t i 1 l i

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/ 5 condhtionsincludingscienic f \\s\\ .)'. \\ N' \\ \\ l ull Anchor - Restraina (6) CASE 1_ ,3 gj Degrees of Freedom I NN - _JN'\\ N N\\ ,'\\ \\\\ \\ '\\ \\ Nl " " ASME III C1 2 or 3 ~ CNS - Non Seismic B31.1 - Stress Limits (Seismic Not Seismic Cat. I Cat. I Piping (TYP.) nelud'ed) (TYP.) Limits (n?.) PIPING AND RESTRAINTS _ Included in the mathematical model of the Sciamic Cat. I Piping m-m 1 \\ .\\. E fy\\ >^><% l CASE 2_ e'atraint "Y" and "Z" ,3 //5 Restraint "X" and "Z" a' \\ -N'\\\\s-d '\\ This oet of. restraints together \\\\ foms a (6) directional restraint. s\\\\. \\ \\ N \\ N Stress limits for all conditions 1.8Sh including seis ic

• Symbol indicates boundary betveen ASME III Class 2 or 3 and non-seismic piping.

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i SB 1 & 2 FSAR 1 RAI 220.20 (3.7(B).2.9) I With regards to peak broading of floor response spectra, we have noted your justification (FSAR Section 1.8) for deviating from Regulatory Guide 1.122 recommendation. Ilowever, provide the assessment of impact, if you were to implement the + 15% peak broadening as required by SRP Section 3.7.2 Subsection II.9.

RESPONSE

The majority of plant components, equipment and piping systems have been qualified by either tests or modal analyses. The impact of implementing a 15% spread of response spectra peaks would required reviews and revisions of qualifying documentation. Many items would require re-testing or re-analyses which, when included with the above review process, would impose a substantial burden on the applicant. Current construction schedule, estimated manpower requirements and cost projections would be negated. Because of inherent design and analysis conservatisms, modifications or redesigns would not be expected from such an implementation. 9 MI-'*** ew.

SB 1 & 2 FSAR RAI 220.21 (3.7(B).2.11} The present technical position of the staff requires that the accidental torsion, based on 5% eccentricity of the larger of the projected base dimensions times the story shear be included in the design of structures. This is in addition to that which results from the actual geocetry and mass distribution of the building. Either indicate your willingness to comply with this position for all Category I structures or provide justification for not doing so.

RESPONSE

The indicated technical position represents a new requirement, introduced in Revision I to the SRP 3.7.2 (July 1981), which has not been incorporated in the design of structures for Seabrook-The Seabrook structures were designed to Revision 0 of SRP 3.7.2, and are essentially complete. The procedure which was utilized for the design of safety-related structures, however, is a detailed and rational approach to represent actual structural behavior and provide a conservative design. All Category I structures have been analyzed dynamically with accurate representations of mass and eccentricity. To develop accurate distribution of forces within the structural elements, most Category I ctructures have additionally been analyzed with finite element techniques for static loads. This method of analysis achieves a realistic distribution of loads, accounting for the effects of eccentricities of both the loads as well as the geometry. The design forces produced from this analysis are furthermore combined with all appropriate load factors to, provide proper safety margins. Allowable =_.,_.

..= ; _ -

concrete stresses used are based on'a design mtx of either f ' = 3000 psi or -~ e f ' = 4000 psi which always achieves more strength at 28 days than design e values providing additional design margin. Consequently, it is our opinion that the 5 percent additional accentricity is not required due to the comprehensive approach which was utilized for the design. l

SB 1 & 2 FSAR RAI 220.22 (3.7(B).2.14) Although you have stated that overturning moments are determined on the basis of three components of earthquake, the subsequent mathematical formulation indicates that you have only considered the moment due to motion in one horizontal direction at a time. However, the staff position requires that the total overturning moment should account for three components of earthquake. Discuss and justify this apparent deviation from the present staff position (SRP Section 3.7.2.II.14).

RESPONSE

Total overturning moments did account for three components of earthquake motion. Definitions of terms in reference formula are in error in this Section of FSAR. Revised Section 3.7(B).2.14 is attached. m-p.- l l I

.I _I. 2.7 8. N ) y. SB 1 & 2 FSAR 4 building and fuel storage building. Tables 3.7(B)-10 and 3.7(B)-11 list the displacements and accelerations computed by both methods for horizontal and vertical directions and SSE and OBE conditions (as noted on the tables) for the containment building. Referenced elevations correspond to mass points as shown on Figure 3.7(B)-22. Table 3.7(B)-19 shows similar information for the fuel storage building, whose modal is shown on Figure 3.7(B)-26. Approximate equivalency can be seen in the results of the two methods. 3.7(B).2.13 Methods for Seismic Analysis of Category I Dams This section is not applicable to Seabrook. 3.7(B).2.14 Determination of Seismic Category I Structure Overturning Moments All seismic Category I structures are designed to resist overturning due to the combined effects of the vertical and two horizontal components of seismic ground motion. A structure's ability to resist overturning is calculated by either of two conservative approaches: moment equilibrium or a work-kinetic energy method. a. Equilibrium Method im(F Dwoud In the moment equilibrium method, the response of a structure bu6 72) %D ree directions)is obtained from the dynamic analyres. (- "Ihe maximum overturning r. c, ment, about the toe of the mat, is computed as: M "h1

1. "h2 0

ww- - where M vertur ng moment' ~ O maximum overturning moment E-

_ _ : i-- in M

= g one horizontal direction J')6 To Srg_:q 0 ~2::f:::i D I CE.W)//C or 2 WT@)/vi Maximum overturning moment - - - ' - in M = g second horizontal direction,, D*JG To (MdcF 7,@~ce DiRGCTQWS 0 F ii;A 43PQ D/% M or M include all dynamic effects on the structure including g h2 tHe dynamic effect of soil caused by seismic motions, The resisting coment is computed as follows: "R " rza (W-v )x --(Vx )<f M., s i Resisting moment where M = R Weight of the structure and any fill W = V Maximum vertical seismic force of structure = acting upward ht)G y0 7;:p g y. . y,- dE C.A L pyj,a Q 3.7(B)-8

' / *p f. 3 h a. i '- ) L SB 1 & 2 FSAR [4 P l? pttrf:.'bs MICC T,7 (C NTd2 ^ C FI V CR O Sr,1 ng. 'l = 9 7 A T%U r.>9p 7%$ Di. ar* ,5 p.;- Maximum vertica' hydrostatic force on the V = h structure actir.g upward. I Horizontal distance of the centroid of the X = g structure from the toe of the mat. Resisting moment due to key action of mat M = b or passive resistance of the structure. The factor of safety against overturning is M FS = R 0 As long as the factor of safety is equal to or greater than 1.10 for SSE and 1.50 for OBE load conditions, the structure is considered stable against overturning. b. Work-Kinetic Energy Method In the work-kinetic energy method, the kinetic energy in a structure due to an OBE or SSE is estimated by b KE = {M. 2 (V )t2 (y )i H. v i 2 where M. = Mass concentration at some point (i) in the structure, , n. s =- = % c. (v ); Maximum total laterial velocity, = g Maximum total vertical velocity, l (V ). = vt (V ). and (V ).= are computed as follows: Ht vt (V )t (y )12 (y ) 2 2 H. x, Hg 2 2 l (V )i (y )t2 (y )g v. z v where (V

• "* E# "" ""

7' Hg" Peak vertical ground velocity, (V ) = j y (V )'. M ximum relative lateral velocity of mass, M, gcc ~N = -f <Q a LCee% of'.L* %.4-ra h(, d (V,); = Maximum relative vertical velocity of mass, M;) M $ -d %{ M th E ; g C<er'.,,4.,.;u, ~ r g,* a fM

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( I2 6 '2 M. N) SB 1 & 2 FSAR \\ 3 % T The work, W, required to overturn the structure is computed asl epCj W M g h+W - W = ] *g where p b t y Total mass of the structure and foundation mat, 4 M = t t w a = g Gravitational acceleration, 5 j h a S ne vertical distance for which the center = y of mass of a structure mus.t be lifted to y .M. reach the overturning position, M , Y ;* 3 h y W ne additional work required to displace = p the soil on the toe side of an embedded structure, ,q U t 't) g{ k b e w rk done by the buoyancy force on the W = submerged portion of a structure. gf0 W The structure is considered stable against ovarturning when the ratio W/KE exceeds the pseeeens safety factorsj bCGCre# ~3 't> /p U. A130L/6 3.7(B).2.15 Analysis Procedure for Damping When the components of a seismic Category I structure or system are constructed of different materials, and these components cannot be uncoupled due to dynamic interation effects, a'n average modal damping value is used for the dynamic analysis of the system. This average modal value is computed from the damping values of the various components, as listed in Table 3.7(B)-1, each weighted by the energy stored in these components in the various modes ._ s f, vibration._ h is,valus i.s_compu_ted.as m {D;E in D = ETn where j th D Average damping value of the n mode = D( Damping value of the i" component r ch O E g Energy stored in the i component in the n mode = Eg Total enggy stored in the structure or system = in the n mode. l The energy values are computed from the stiffness matrices of the various components and the mode shapes associated with undamped vibration. 1 By this procedure, a diagonal damping matrix is computed allowing for the uncoupling of the equations of motion and the use of modal super position. l 3.7(B)-10

SB 1 & 2 FSAR RAI 220.23 (3.7(B).3) Discuss the seismic analysis, including cable jerking effect, of the gantry crane in the containment structure. Provide the model and details of the analysis for the staf f's review.

RESPONSE

1.0 Introduction The Seabrook polar crane is c gantry type, with legs 74 ft. high, and a span of 103 ft. and a dead weight of approximately 432 tons. The crane is rated to lift a 420 ton load with the main hoist, and 50 tons load with the auxiliary hoist. During a seismic event, the crane is postulated to be unloaded and in a parked position. Therefore, hoist cable rope jerking effects which result from a slack cabic condition with the lif ted load, is not a consideration for this crane. The crane is not required to be operational after the reismic event, but is designed to remain in place during and after the seismic event. Both the trolley and bridge wheel trucks are equipped with devices which prevent the trolley and bridge from disengaging from their respective runway rails when the crane is subjected to seismic excitations. Figure 220.33-1 shows the bridge trucks gantry leg arrangements at each end of the crane; Figure 220.23-2 shows the trolley arrangement. 2.0 Seismic Analysis A dynamic analysis using the response spectra method was performed to determine response loads of the crane when exposed to seismic excitations. The response spectra method requires the crane to be idealized as a linear 71'astic ~isystiem"and, therefore, non-linearitiesassch'is plastic deformation, sliding friction, and clearances between moving parts of the crane system were not considered. ANSYS, a large scale general purpose computer program was used to perform the crane analysis. The dynamic analysis was of the mode frequency (modal) type, solving for the resonant frequencies and the mode shapes that characterize the crane. The modes with meaningful participation in a given direction (mode coef ficients greater than 5% of the principal "X"-mode coe f ficient, 2h: of the principal "Y"-mode coef ficient and 15% of the principal "Z" mode coefficient) were directly expanded by the computer program to' yield the expanded mode shape, the element stresses and the reaction forces and moments. The crane mathematical model was represented by a generalized three-dimensional system of node points interconnected by various finite elements i representing straight and tapered beams. All masses and inertias were distributed among the nodes whose degrees of freedom characterize the response of the structure. The interconnecting finite elements were i

1 SB 1 & 2 FSAR assigned stiffness equivalent to that of the actual structure. The mathematical model of the crane, shown in Figure 220.23-3, represents, as accurately as possible, the flexibility of the gantry legs, bridge girders, leg connections, girder connections, and the gantry trucks including wheels. The gantry legs were modelled as tapered beams; the girders, leg connections, and girder connection components were modelled as uniform beams. These elements have the properties of the corresponding parts of the actual The trolley, equalizing trucks, wheels and certain short connections crane. were modelled as rigid members capable of transmitting the loads only. Lumped masses were assigned to represent the mass of the trucks, trolley and load. The trolley was modelled as a rigid structure, based on past experience with similar equipment. A model of a typical trolley is shown in Figure 220.23-4. The crane system was considered decoupled from the runway at the bridge wheels rail interface. The boundary condition at these locations assumes the crane to be pinned to the runway rail. The seismic analysis considered the crane to be in a parked position, with adequate clearances between the crane structure and containment wall to allow for dynamic deflections of the crane. During a seismic occurrence, it is not required to postulate the crane to be in an operational mode, there fore, the crane mathematical model did not include a lifted load attached to the hook and suspended by the hoist cables. The dynamic degrees of freedom were selected to obtain the desired modal shapes. Placement is such to include coupled modal shapes due to eccentricities. I Because the crane is polar and is not fixed with respect to the North-South (NS) or East-West (EW) directions, an amplified response envelope encompassing both the NS-and EW direction was conservatively derived.to j provide horizontal excitation in both the X and Y directions. The vertical excitations are approximated by curves with fewer inflection points. Both the horizontal envelope and the vertical approximation provide acceleration values approximately equal to or slightly greater than that specified at all frequencies. The normal mode approach was employed for the analysis of the components. All significant eigen values and eigen vectors were extracted. Those modes with frequencies less than 10% apart that normalize on the same subsystem were combined directly in an absolute manner. All modes with a meaningful participation were summed by the square-root-of-the-sum-of-the-squares method after direct summary of response to frequencies within 10%. The ef fects of the orthogonal excitations were also combined by the square-root-of-the-sum-o f-the-squares method. The resulting dynamic component of stress, deflection, force, etc., was then algebraically added to, or subtracted from, the corresponding static component to yield the maximum positive and negative resultant.

SB 1 & 2 FSAR The crane system seismic analysis was conducted to determine the worst case loading resulting for different positions of the trolley on the bridge. Three trolley positions were selected: trolley at mid-span, trolley over the A-A legs, and trolley over the B-B legs. The resulting forces were used. in checking the structural trucks, axles, equalizing beams and pins. Because of the difficulty of selecting the worst possible combination of loadings applied at one time, the maximum force in each direction was chosen and applied to the crane simultaneously. Since the crane satisfactorily resists this loading, it will safely resist all other possible loading situations. Table 220.23-1 gives the natural frequencies (eigen values) of the crane system in its three orthogonal directions. Listed in Table 220.23-2 and 220.23-3 are the upkick forces on the crane wheels that tend to lift the crane. These forces have been divided equally and the force per earthquake lug is given for each truck. The maximum stresses in the bridge structure occur when the trolley is located at mid-span; the combined stresses are listed in Table 220.23-4. Maximum stresses in the gantry leg occur when the trolley is located over the B-B leg (see Fig. 220.23-1), and are listed in Table 220.23-5. g""{ M 9 % e V. 9 e l l i l i I i l i l I c

SB 1 & 2 FSAR TABLE 220.23-1 POLAR CANTRY CRANE NATURAL FREQUENCIES / Trolley at Midspa'n X-Mode Y-Mode Z-Mode Mode Coeff. Freq. Mode Coeff. Freq. ' Mode Coeff. Freq., 302.1 .8824 146.4 1.258 12.97 5.446 .5501 12.20 13.03 4.008 1.070 .8824 .3281 12.14' 4.029 2.777 .5516 12.40 .07399 12.40 2.062 5.264 .2596 12.14 .06522 3.008 .8358 11.56 .2054 6.617 Trol' ley Over A-A Legs X-Mode Y-Mode Z-Mode Mode Coeff. Freq. Mode Coeff. Freq. Mode Coeff.' Freq. 303.9 .8796 110.8 1.604 3.902 7.416 .6747 11.65, 16.17 2.807 .7320 13.86 .1114 13.86 15.67 2.231 .6196 8.796 .08156 3.336 4.463 4.610 .3903 1.591 .08134 7.416 1.320 10.10 .1663 19.52 ^ ~m -Na e Trolley Over B-B Legs X-Mode Y-Mode Z-Mode Mode Coeff. Freq. Mode Coeff. Freq. Mode Coeff. Freq. 305.5 .8771' 113.0 1.496 3.079 .8771 .6920 11.27 26.81 2.278 2.162 7.492 .1885 7.492 8.386 2.808 .8899 13.95 .1195 1.500 5.6f6 4.530 .6946 11.27 .09432 3.191 2.271 3.072 .2967 16.05 l I 'l

SB 1 & 2 FSAR TABLE 220.23-2 UPKICK FORCES (LBS) DURING SSE TROLLEY AT CENTER FORCES IN E DIRECT. FORCES IN E DIRECT, UPKICK FORCES NODE DUETOS+/X2+y2+z2' DUE TO STATIC S + /X2 + y2 + z2'-2S - 101 300,999 667,781 165,437 102 211,564 667,781 76,002 103 214,918 72,098 70,722 151 298,812 66,020 166,722 152 209,412 66,020 77,372 153 212,765 70,337 72,091 l 201 318,900 75,719 167,462 202 220,549 75,719 69,111 203 223,810 80,036 63,738 251 315,666 73,217. 169,232 , _ 71,191 252 - 21,7_,625h r %-737217 % p c,w_ 253 220,886 77,534 65,818 FORCE PER LUG TRUCK FORCE (LBS) 101 102 156,080 103 151 152 158,092 153 201 202 150,155 203 251 252 153,120' 253

SB 1 & 2 FSAR TABLE 220.23-3* UPKICK FORCES (LBS) DURING SSE TROLLEY OVER B-B LECS FORCES IN E DIRECT. FORCES IN E DIRECT. UPKICK FORCES NODE DUE TO S + /X2 + y2 + z2' DUE TO STATIC S + [X2+Y2 + g 2 '-2 S 101 190,030 43,982 102,066 102 137,847 43,982 49,883 103 141,633 - 48,303 45,027 151 190,385 42,363 105,659 152 137,342 42,363 52,616 15,3 141,119 46,684 47,751 201 502,565 99,667 303,321 202 326,147 99,667 126,813 203 328,495 103,988 120,519 251 499,558 97,019 305,520 _,252_ - - _ 323,857 ..g97,0h_ ~ ~ 129,819 _ __ l 253 326,199 101,340 123,519 FORCE PER LUG TRUCK FORCE (LBS) 101 102 98,488 103 151 152 103,013 l 153 l 201 202 275,327 203 251 252 279,427 l 253 l l t

l SB 1 & 2 FSAR. l TABLE 220.23-4 BRIDGE STRESSES (PSI) DURING SSE TROLLEY AT MID-SPAN l Node DYN X DYN Y DYN B STATIC S + (X2 + y2 + pj2'

• 301 8,693 14,970 514 785 18,104 302 4,245 3,559 3,192 2,372 8,765 303 1,102 13,513 5,217 3,860 18,387 304 4,599 3,740 3,202 2,255 8,992 305 54 3,982 90 305 4,288 351-8,599 14,992 406 751 18,039 352 4,199 3,569 3,020 2,299 8,583 353 165 13,550 4,911 3,753 18,166 354 4,540 3,653 3,033 2,187 8,756 355 42 4,017 103 270 4,289

~ meg u ne-m, 4 l l S -,-w . - -. - - -,- - m e _,,_.,,,__,,.,,._.g,,.__,,,

SB 1 & 2 FSAR TABLE 220.23-5 APPARENT LEG STRESSES (PSI) DURING SSE TROLLEY OVER B-B LECS CA l i Node DYN X DYN Y DYN Z STATIC S + SRSS 210 A 4,501 14,822 868 1,753 17,268 B 6,509 22,752 1,086 1,942 25,632 211 A 14,969 25,937 1,231 1,070 31,042 B 16,995 17,971 1,576 2,401 27,185. 211 A 14,866 12,091 1,493 768 19,988 B 16,910 15,980 1,223 2,595 25,893 212 A 19,542 23,101 899 576 30,847 B 21,600 19,214 579 2,616 31,531 212 A 19,350 8,975 247 235 21,567 ~ D ' ' 21,578 10,083 "$ 2' 2,835 26,680 ~ 260 A 4,557 22,201 883 1,941 24,622 l B 6,585 14,265 544 1,649 17,370 261 A 14,884 14,987 1,240 759 21,172 B 16,929 22,965 1,553 2,607 31,180 261 A 14,831 17,168 894 955 23,660 B 16,876 13,294 222 2,301 23,819 262 A 19,493 15,375 846 242 25,083 B 21,553 19,282 545 2,844 31,768 262 A 19,395 13,049 257 480 23,858 B 21,609 11,969 1,106 2,481 27,208 g

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SB 1 & 2 FSAR RAI 220.24 (3.7(B).3.7) l The modal response for closely spaced modes is obtained by equations (1) and (2) given in Section 3.7(B).3.7 of the FSAR. Confirm that equation (1) gives conservative results and meets the intent of the criteria of Regulatory Guide 1.92,,Rev. 1, 1976. If not, justify the deviation.

RESPONSE

See response to RAI 220.1 (3.7.2, 3.7.3), Amendment 44, February 1982. i F

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0 . a t RAI 220.25 (3. 7(B).3.12) i In general, the staff finds the procedure indicated in this section acceptable for the buried systems suf ficiently flexible relative to the j nurrounding and underlying soil. Ilowever, provide a discussion on the types of waves and angles of incidences considered in your analysis for staf f's review. Also, discuss the amplification of input motion due to the backfill over the bedrock. Re sponse s The responses of soll medium to an earthquake motion are due to three clastic waves: shear waves, compression waves, and surface waves. Ilowe ve r, the relative contribution of each type to the velocities and accelerations associated with the design earthquake are not well defined. For the analyses of the buried pipes, a conservative assumption is that the velocities and accelerations result f rom a singic shear wave of oblique incidence, because the maximum stressed due to compressional waves, shear waves, and surface waves do not occur simultaneously. In 4 the analysis of the buried piping, the maximum soil strain E was m conservatively calculated by ur,ing the following expression: I c= V. 2 C, m Whe re : V = maxim: ground velocity m C = shear wave velocity s Where the underground piping system is located in excavated rock i t re nche s, the pipes are supported on bedding (approximately 24" thick) of structural fill (of f-site borrow as described in FSAR Subsection 2.5.4.5) over the bottoms of the excavated, rock trenches... Amplification _of,, seismic motion does not occur within~a thin, confined stratum such,as this. In certain regions, the piping has been placed on of f-site borrow which has a thickness of up to 37 feet. All of this piping is located near reinforced concrete structures and is, consequently, somewhat confined. Analysis is presently being performed to investigate the possibilities of amplification of input motion in these regions. i i e t F i i I l . -. ~ -- -

SB 1 & 2 FSAR RAI 220.26 (3.8.1) Have you considered the effect on containment structural design of non-linear transient temperature gradient across the containment wall thickness caused by the LOSS-OF-COOLANT-ACCIDENT (LOCA)? If not, please include this effect in your design or justify the omission.

RESPONSE

Transient temperature gradient across the containment wall thickness caused by LOCA was considered in the containment structural design. The effect of temperature gradient across this wall, linear or non-linear, combines with the 9!.fect of accident pressure so as to reduce the rebar tensile stress of the inner layers of rebar and to increase the rebar tensile stress of the outer layers. Per ASME B & PV Code, Section III, Div. 2 CC-3422.1, including Winter 1977 Addenda, under thermal loads a general membrane yield state is permitted with a limit on the amount of calculated net rebar tensile strain. In this design, the thermally induced strains were superimposed on those due to mechanical loads, and the maximum rebar strain was shown to less than the 2 x f5y limit. For analysis purpose,(( y is defined as the nominal yield stress divided by Young's modules. -a c =- I a;i,5 ' 6

d . i SB 1 & 2 FSAR t RAI 220.27 (3.8.1.6) Confirm that the materials of construction are in accordance with Article CC-2000 of ASME Section III Division 2 Code, augmented by Regulatory Guide 1.136. If not, identify the deviations and justify the same. RESPONE: Seabrook containments are built to ASME Code Section III, Division 2, 1975. .We are currently asking for a Code Interpretation for the use of prepackaged grout and epoxies. All other materials requirements of Article CC-2000, as augmented by Regulatory Guide 1.136, are being met. i i i l i l I I l i l l -4,...~ .~. n-

4 = SB 1 & 2 FSAR RAI 220.28 (3.8.1.3) Containment load combinations and load factors as shown in Table 3.8-1 of the FSAR do not cover all the loading combinations of ASME Section III Division 2 Code, Table CC-3230-1. The factored loads for extreme environmental case in your table do not include Ro (normal pipe reactions). Provide justification for this exclusion or include it in your analysis as required by SRP Section 3.8.1.

RESPONSE

Omission of R was due to a typographical error. Ro (norm.; pipe reactions) o have been added to load combinations numbers 5a and 5b under extreme environmental load case in Table 3.8-1. Overall ef fects of R on the design o of the containment structure ere very small. ....c.

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SB 1 & 2 FSAR i RAI 220.29 (3.8.2) The Table 3.8-6 of the FSAR shows load combinations for equipment hatch and personnel locks. It appears that you have not considered all the load combinations covered by the SRP Section 3.8.2. Confirm that the load combinations meet the requirements of the SRP Section 3.8.2. If not, justify the deviations.

RESPONSE

The load combinations appearing in Table 3.8-6 and the stress limits of . Table 3.8-10 for the equipment hatch and personnel locks are in agreement with the load combinations and stress limits defined in SRP 3.8.2, Rev. O, 11/14/75. The applicable design loads are described in FSAR Section 3.8.2.3. From the applicable loads, it has been determined that load combination No. 5 (D+L+Pa+Ta+E') and the associated allowable stress limits (Pg;f Sm, PL 6 1.5 Sm and PB+PL 6 1.5 Sm) for regions classified as not integral and not continuous will dictate the design. This combination is compatible with the loads and limits delineated in SRP Section 3.8.2, i Rev. 1. As implied, all the loads applicable to the design of the Seabrook plant are listed above. Others which may appear in Rev. 1 of SRP 3.8.2 do not apply. Hence, an FSAR presentation geared to a review by the contents of Revision 1 would show adequate design. _L - C E e l l l l l

o o SB 1 & 2 FSAR RAI 220.30 (3.8.2) The Table 3.8-19 of the FSAR shows stress limits for equipment hatch and personnel locks. Some cases in this take are not as conservative as those in SRP Section 3.8.2. The current acceptance criteria is delineated in Table 3.8.2-1 of SRP Section 3.8.2, Rev. 1 (Attachment 2). Conform that you meet the current SRP criteria or justify the deviations from them.

RESPONSE

See the respons* to RAI 220.29. 7-C ,-?. --r~. 4 l 1

SB 1 & 2 FSAR RAI 220.31 (3.8.3) The FSAR is not clear about the design of the primary shield wall of the containment internal structure for the loss-of-coolant-accident (LOCA) loads. Confirm if time history analysis is performed treating LOCA loads as dynamic time-dependent loads or static analysis is performed using the peak of the LOCA loads amplified by appropriate dynamic factors. If not, explain and justify the manner in which you have determined the LOCA loads and designed the primary shield wall.

RESPONSE

The primary shield wall was designed under the accident condition considering the effects of LOCA loads, such as pressure in the reactor cavity, temperature, jet forces and forces transmitted by the reactor vessel, seismic loads, etc. The design pressure loads were conservatively considered as the peak transient-pressure differential on the shield wall. Other LOCA forces on the structure were determined using dynamic time dependent analysis. The peak values of these loads were conservatively used as equivalent static loads. 65 N 'Q* N man M g ~- g e e ee = ,e.,n,

o SB 1 & 2 FSAR RAI 220.32 (3.8.3)(3.8.4)(3.8.5) The staff presently accepts the use of ACI-349 as aagmented by Regulatory Guide 1.142 in the design of Category I concrete structures other than containment. FSAR Sections 3.8.3, 3.8.4, and 3.8.5 have mentioned the use of ACI-318 Code for Concrete Structure. Evaluate and assess the impact of using ACI-349 as augmented by Regulatory Guide 1.142. Identify specific deviations from the staff position and the areas where use of ACI-318 Code results in less conservative design. Also discuss specific means for disposition of these less conservative design areas,or justify their design adequacy.

RESPONSE

The design of the Seabrook Category I concrete structures was based on recognized and accepted applicable design codes in effect throughout the major segment of the design efforts. The predominate code used being ACI-318. The results of a detailed review of ACI-318 versus ACI-349 will be provided by July 1982. -na. 's l l l l l l l I I

a SB 1 & 2 FSAR RAI 220.33 (3.8.4) Among the load combinations for Category I structures as shown in the Table 3.8-16 of the FSAR, tne " unusual load" for concrete has seven load combinations. The 4th combination among these does not correspond to the requirements of the SRP Section 3.8.4, Subsection II.3.b(ii).(d). The pipe break loads tre not included in this combination. Confirm that you will or you do meet the SRP requirements, otherwise justify the deviation.

RESPONSE

Pipe break loads (Rrr, Rrj, R m) associated with postulated break on the r high energy pipe were inadvertently left out from the 4th load combination under " unusual load" for concrete in Table 3.8-16. High energy pipe lines occur only in a limited number of Category I structures, and the loads produced by their postulated rupture affect only the local area at the restraint. These ef fects have been considered in the design of the pertaining structures under the abnormal / extreme environmental loading condition, i.e., the 5th load combination undir " unusual load" for concrete in Table 3.8-16, and it was found to have adequate design margin. The structural acceptance criteria for all other loading conditions, as delineated in the Table 3.8-16, was also satisfied. Table 3.8-16 of the FSAR has been revised to include the pipe break loads in the 4th load combination under " unusual load" for concrete. From a comparative study of the effects of design loads included in the 4th and 5th load combinations, it is concluded that the 5th load combination governs the structure design, and hence, the inclusion of pipe break loads to the 4th load combination does not affect the present design. Refer also to FSAR Subsection 3.8.4.3 for a discussion of the pipe break loads. m-~ rr L 9 ...... ~

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9 e... RAI 220.33 (3.8.4) The f uel storage building contains a spent fuel pool. A copy of " Minimum Requirements for Design of Spent Fu e l Ra c k s " is enclosed (Attachment 5). provide the information as required and discuss your compliance with this position.

Response

The detailed design of spent fuel racks will not begin until approximately April 1, 1982. A design report summary addressing all items in Appendix D to SRP, Section 3.8.4 (Rev. 1, July 1981) and also, " Review and Acceptance of Spent Fuel Storage and Ibndling Applications", Ja nua ry 18, 1979 revision, will be provided to the NRC by November 1, 1982. The spent fuel rack design will comply with Appendix D to SRP, Section 3.8.4 (Rev. 1, July 1981). w - - - - m -:= I

E o..- RAI 220.37 (3.8.1) Pro virb .t o ottim.ite capacity analysis, of the containment re ;p.on' i n;>.to the int erna l p re s s u rn-build up due to.iccidents. The 3pil d. l i ac a a<! the staff posittoo on t h i r, sahjeet i s enc losed ( At tacliment 6).

Response

The results of an ultimate capacity analysis of the cootiinment, employi ng the guidelines and staf f poultion ( Attachment 6), which was pro virled wi t h t hi s RAI, will be provf <*ed to the NPC by Oc t o be r, 1982. . gu. _}}