ML20052G986

Responds to Auxiliary Sys Branch Questions CS 410.1,4,6,7,8, 11,12,13,14,15,16 & 17.Responses Will Be Incorporated Into PSAR Amend 69,scheduled for 820528

ML20052G986
Person / Time
Site:	Clinch River
Issue date:	05/14/1982
From:	Longenecker J ENERGY, DEPT. OF
To:	Check P Office of Nuclear Reactor Regulation
References
HQ:S:82:032, HQ:S:82:32, NUDOCS 8205190216
Download: ML20052G986 (15)

Text

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Department of Energy Washington, D.C. 20545 Docket No. 50-537 HQ:S:82:032 MAY 141982 1

Mr. Paul S. Check, Director CRBR Program Office Office of Nuclear Reactor Reculation U.S. Nuclear Regulatory Commission Washington, D.C. 20555

Dear Mr. Check:

RESPONSES TO REQUEST FOR ADDITIONAL INFORMATION - AUXILIARY SYSTEMS

Reference:

Letter, P. S. Check to J. R. Longenecker, "CRBRP Request for Additional Information," dated March 15, 1982 This letter fonnally responds to your request for additional information contained in the referenced letter. .

Enclosed are responses to Questions CS 410.1, 4, 6, 7, 8, 11, 12, 13, 14, 15,16, and 17 in the area of auxiliary systems. These responses will also be incorporated into the PSAR Amendment 69, scheduled for May 28.

Sincerely, J n R. Longene er, Manager Licensing & Environmental Coordination Office of Nuclear Energy Enclosure .

cc: Service List Standard Distribution Licensing Distribution D00/

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B205190216 820514 PDR ADOCK 05000537 6' /

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heg~e - i 82-I)287 [8,22] #37 I

Question CS410.1 Discuss whether f ailure of nonselsmic Category I or non tornado protected water tanks and vessels due to the SSE or design tornado can recult in flooding of essential structures, systems and components. If this possibility exists, provide the results of a f ailure modes and of facts analysis that demonstrates that required saf ety f unctions, incl uding saf e shutdown, wil l not-be compromised by the postulated f ailures.

Response

(a) Tanks Located Indoorst With the exception of the tanks listed below, all water storage tanks located in Category I structures are designed as Seismic Category I components and are tornado protected.

Tank Seismic Category Location Hot Water Non-Seismic Category l Control ButIding Heater (80 gal)

Normal Chi l ied Water Exp. Tank 23NCT003 Non-Seismic Category I Steam Generater Bldg.

(1200 gal) (Intermediate Bay)

Normal Chil led Water Chemical Addition Tank 23NCT008 Non-Selsmic Category 1 Steen Generator Bldg.

(70 gal) (Intermediate Bay)

As can be determined from the above list, the tank capacities are very i small. Rupture of these tanks results in a negligible buildup of water in these areas. Since all safety related equipment in the Nuclear Island l Bulldings are mounted on minimum 4" concrete pads, rupture of the above tanks will not result in flooding of essential structures, systems and components.

(b) Tanks Located Outdoorst As described in PSAR Section 3.4, the Category I structures have been l designed to withstand the of facts of natural phenomena, including the I worst case flooding conditions (which exceeds the rupture of any non-category I tanks in severity) without adverse of facts: Therefore, flooding of essential structures, systems and components is prevented.

QCS410.1-1 Amend. 69 May 1982 -

Pfg~e - 3 5f~0257 [8,22] #37 Question CS410.4 (9.1.4) l Describe the ' emergency cooling" process instituted in case of power failure l to the f uel transfer port cooling insert blower during core component pot i (CCP) transfer (references Section 9.1.4.7.3) . '

Response

PSAR Section 9.1.4.7.3 has been revised to respond to this question.

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QCS410.4-1 l Amend. 69 i May 1982

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Pgge - 4 82-0287 [8,223 #37 9.1.4.7.3 safety Evaluation The transient dose rate from the highest powered spent f uel assembly is less i

than the criteria in Sections 12.1.1 and 12.1.2 at the surf ace of the adaptor body. This significant dose rate exists only during the short time (a few minutes) when a spent fuel assembly travels through the adaptor and floor valve into the EVTM. The closest location where personnel can be exposed to the radiation source is more than 10 ft. from the adaptor surf ace for normal operation, and more than 2 f t. from infrequent maintenance operations. Both locations are on the RW operating floor, above the adaptor. Therefore, Integrated exposures are low.

Cooling of spent oore assemblies in the reactor or EVST fuel transfer port is adequate to maintain the assembly cladding temperature below the 1250oF limit for normal operations and anticipated events. During normal operations, h e transit time of the core assembly through the port is short (a few minutes) so that there is no significant heatup. In the event that an assembly becomes Immobilized in the port, design provisions to maintain the cladding temperature below 12500F wil d ce used. If Immobilization of an assembly is the result of a mechanical failure of the EYTM grapple drive' system, the backup cooling system for the port may be turned on to provide the necessary cooling. If Immobilization is the result of a loss of power (which would also disable the backup cooling system), the EVTM grapple drive system may be operated manually to raise or lower the core assembly to a location (EVTM or sodium pool) where adequate passive cooling is provided to maintain the cladding temperature within the 12500F limit. However, those operator actions are required only to maintain f uel temperatures within normal limits, in the unlikely event that a core assembly becomes Immobilized in the port for a longer time by coincident drive system mechanical failure and loss of power or -

f ailure of the operator to respond to this condition the cladding temperature would exceed 12500F but would remain below the 15000F limit for unlikely and extremely unlikely events. '

9.1.4.8 Scent Fuel Shinning cack The Integrity of the SFSC design will ensure suf ficient margins to meet all requirements stipulated in the applicable regulations, especlully 10 CFR 71.

The shipping cask is discussed in this section only to the extent that conditions to which It is subjected inside the RSB are potentially more severe than those design conditions specified in 10 CFR 71.

Regulation 10 CFR 71, paragraph 71.36, states that the cask design shall withstand a hypothetical accident characterized by a 30-ft drop onto a flat, essentially unyleiding, horizontal surf ace without exceeding a specified reduction in shielding and containment of radioactive material. The LWBR spent fuel shipping cask wilI be designed to withstand, with no release of radioactivity, a maximum deceleration of 123 g if dropped 30 ft onto an unylolding surf ace. The largest height for a potential SFSC drop in the CRBRP is the 72-ft vertical distance of the SFSC handling shaf t.

9.2-62 Amend. 69 May 1982

P's,ip ' 5 82-0287 [8 0'22] 537 9.1.4.8.1 Design Ramis The free f all impact energy of the 72 ft SFSC drop to the bottom of the cask  !

handling shaf t shall be limited to an amount less than that experienced in a '

hypothetical cask accident specified in 10 CFR 71.

. 9.1.4.8.2 Design Descriotton The SFSC is handled within the RSB and lowered and raised in the cask shaf t by the double reeved RSB bridge crane using rigging specially designed and tested f or the SFSC. Preliminary analysis indicates that a 9.2-62a Amend. 69 Why 1982

Pcge - 4 82-0287 L8,22J #37  :

ouestion esd10.6 (9.6.1)

The kitchen and toilet exhaust f ans are nore-saf ety related. Verify that ducts leading to these f ans are at least seismic Category lli, it appears f rom Flpre 9.6-1 that these f ans exhaust air from other spaces in addition to the kitchen and toilets. Discuss the consequences of loss of these f ans.

Response

The kitchen and toilet exhaust f ans, along with their associated ductwork and accesscries are Seismic Category ill. in addition to exhausting the toilets (Cel is 425, 426, 435) the toilet exhaust f an also exhausts air from janitor closets (Cells 437A, 439) ar,d the chart storage roon (Cell 437). The kitchen exhaust f an exhausts air from the kitchen (Cell 427) and the halon tank storage (Cel l 421 A). The loss of the kitchen and/or toilet exhaust f ans would have no of f act upon the operation of the saf ety related control roan HVAC system.

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QCS410.6-1

Amend. 69 l

May 1982

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Page - 7 82-0287 [8 0223 137 Question CS410.7 (9.6.1)

On a signal of high levels of toxic chemicals or smoke in the control room IWAC Intake ducts, the path for outside air supply to the control room wilI be routed through filter units. Provide the capability of these filters to remove toxic chemicals and products of combustion.

Response

As stated in Sections 9.6.1.2.1 and 6.3.1.6.2, upon detection of toxic -

chemicals or smoke at either control room Intake, the isolation valves for the intake will automatically close and vill not be routed through the filter units. Therefore, the capability to remove toxic chemclais and products of combustion is not required for the filter units.

1 QCS410.7-1 Amend. 69 May 1982

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Question 410.8 (9.6.1)

On Figure 9.6.3 indicate the interface between the safety-related switchgear room HVAC air intake ducting and the non-safety-related MG set HVAC subsystem air intake ducting.

Response

The outside air intake shown on Figure 9.6-3 is a schematic representation of a 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> fire-rated chase. This intake and chase is shown on Figures 1.2-70 and 1.2-71. Individual intake ducting is provided for each HVAC unit and is connected to the intake chase. Each opening into the intake chase is protected by a 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> rated fire damper. The interface between safety-related switchgear room HVAC intake ducting and non-safety related MG set HVAC intake ducting is the chase as shown below.

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.ToSWGR_g i U W I T " A"_ i I

.ElRE DAMPER (JY P. )

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UMIT"B"  !

_To MG j SET UNIT 4,  ;

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~20287 [8,22] #37

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Page '- 9 '82 Question CS410.11 (9.6.2)

Manual valvos are provided in the RAPS celis HVAC exhaust ducts. These valves are the only means of isolating a contaminated RAPS celi from the realnder of the HVAC exhaust system. Justify the lack of remotely-operating valves for this isolation f unction. Discuss the adverse consequences of high radiation levels preventing operation of a manual RAPS cell isolation valve when required by a release of radioactivity to the RAPS cell.

h vonse  !

As described in Section 9.6.2.2.5 and shown on Figure 9.6-9, the manual valves are not the only means to isolate the RAPS celis from the remainder of the HVAC exhaust system. A radiation monitor and an automatic valve are located in the RAPS colis exhaust header. Upon detection of high radioactivity, the valve wIII automatically elose, thereby Isolating alI the RAPS celIs from the remainder of the HVAC exhaust system. The leaking celi wilI then be Isolated from the remaining RAPS celis by closing the manual valye serving the leaking celi. The manual valves are located outstde the RAPS celis for va!ve accessibility, and as such, the plant operator will not be exposed to the ,

released radioactivity to the RAPS celis. t t

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QCS410.11-1 Amend. 69 May 1982

P ge - 10 82-0287 [8,22] #37 Question CS410.12 (9.6.2. 9.6.3)

Describe the protection af forded redundant, saf ety-related components of the reactor containment building HVAC system, annulus filtration system, and reactor service building HVAC system to prevent common mode f ailures of the components.

Ansponse All redundant saf ety-related components of the HVAC System are Seismic Category 1, located in separate fire zones, provided with independent IE control systems, connected to separate divisions of Class 1E power supplies, and connected to separato loops of the emergency chilled water system as appropriate to prevent common mode f ailures of the components. For detai l ed description and saf ety evaluation of these systems ref er to Sections 9.6.2.2, 9.6.2.3, 9.6.3.2, 9.6.3.3 and 6.2.6.

QCS410.12-1 l Amend. 69 l May 1982

P;ge - 8 82-0287 L8,22J #37 Duestion CS410.13 (0.6.3)

As shown on Figures 9.6-7 and 9.6-7a, several lengths of reactor service building HVAC system ducting in the " fuel handling accident mode" flow path are not Seismic Category 1. Justify the lack of a Seismic Category I rating f or this ducting.

Response

All ductuork associated with the RSB clean-up filter unit, including the " Fuel Handling Accident Mode" flow path is Seismic Category I as described in Sections 9.6.3.3 and 6.2.6. Figures 9.6 7 and 9.6-7a will be revised to clearly indicate this.

QCS410.13-1 Amend. 69 May 1982 i e - _ _ _ _

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Page - 12 82-0287 [8,22] #37 Question CS410.14 (9.6.2 (9.6.3)

The RAPS and CAPS cells HVAC exhaust system could potentially vent airborne radioactivity from these celIs. Justify the Iack of a Seismic Category I ciassifIcation for these exhaust ducts and a saf ety ciassifIcation of Quality Group C for the exhaust ducts.

Response

The RAPS and CAPS cells which could potentially contain the highest amounts of radioactivity are the CAPS Cold Box Cell 378, the RAPS Cold Box Celi 105 BH, and the noble gas storage vessel Cell 105 Bl. These cells have ASE 111/3, Seismic Category I HVAC exhaust ducts up to and including the autanatic isolation val ve. The next highest potential amounts of radioactivity are contained by the recycle vessels cell 105 BC, the RAPS surge vessel cell 105 BF, and the CAPS surge vessel celi 371. The HVAC exhaust ducts from these cells are designed to remain intact following a SSE, up to and including the automatic isolation valve. Since a f ailure of the HVAC exhaust ducts for cells 105 BC,105 BF or 371 will result in conservatively calculated radiation doses at the site boundary of less than 0.5 ram to the whole body; using Regulatory Guide 1.26 Section C.2.d as guidance; less than Group C quality standards (ASE III/3, Seismic Category I) are acceptable.

The RAPS and CAPS exhaust systems are undergoing redesign and this response is consistant with the new design. PSAR Sections 9.6.2.2.5 and 9.6.3.2-3 and Figure 9.6-9 will be revised in the f uture to reflect the redesign.

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QCS410.14-1 Amend. 69

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Pqge -~ 10 82-U281 L8,22J PSI Question CSA10.15 (0.6.3) l Radiation monitors are provided in the exhaust ducts of the reacter service building-radweste area HVAC system. If abnormal radioectivity is detected, the exhaust air is directed to the system's exhaust fIIter unit and exhausted by an exhaust filter f an to the exhaust vent. Justify the lack of a Ssi m ic Category 1, Quality Group C classification for the exhaust isolation dampers and the downstroem exhaust filtration piping and filter units.

Response

As described in Section 15.7.2.5, there are no adverse consequences of a f ailure of the liquid radweste system. The reactor service building -

radweste area is a non-saf ety related, Seismic Category ill building as described in Section 3.8.4.4.3.2. Accordingly, the reactor service building -

radweste HVAC system, including the exhaust isolation dampers and the downstream exhaust filtration piping and filter unit, is also designed to Seismic Category ill.

QCS410.15-1 Amend. 69 May 1982

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1 OuestIon CSd10.16 (9.6.4)

The turbine generator building HVAC system is provided with a radiation monitoring system to sample and analyze tritium in the exhaust air released f rom the building to meet the requirements of 10 CFR 20. Justify the lack of seismic Category I, Quality Group C isolation dampers to contain an e>cessive release of radioactivity.

M me The trittun levels are described in Section 11.3.6.2 and are inconsequential.

These levels, at best, can only be measured by sampling and laboratory analysi s. The need for " Isolation dampers to contain an e>cescive release of radioactivity" is not justifled.

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QCS410.16-1 Anend. 69 May 1982

Page - 12 82-0287 [8 022.]137 l

Ouestion cs410.17 (9.6.6)

The primary sodium tank cell unit cooler is not saf ety grade. Describe the consequen::es of the loss of this unit cooler.

Response

As described in Section 9.3.2.2.2, the Ex-Containment Primary Soditan Storage Tanks are used only during plant shutdown for Initial fill or planned maintenance involving drainage of primary sodium. These tanks are normally ,

empty and do not perf orm a saf ety function. If the unit cooler is lost while j these tanks contain sodium, it is not expected that the colI temperature rise will af f act the structural Integrity of the cells and equipment within. To verify that the expected cell temperature rise is not detrimental to the cell and the equipment within and suf ficient time is available for corrective action, a thennel transient analysis will be performed and the result of this analysis will be presented in the PSAR. In addition, alarms are provided to alert operator of the loss of cell cooling and administrative procedures will be used to re-estabiIsh cooling to the cel1.

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l QCS410.17-1 Amend. 69 May 1982 l

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