ML19276E486

Forwards 1978 Annual Rept Describing Facility Changes,Tests & Experiments Conducted W/O Prior NRC Approval.Rept Submitted Per 10CFR50.59(b)

ML19276E486
Person / Time
Site:	Vermont Yankee File:NorthStar Vermont Yankee icon.png
Issue date:	03/01/1979
From:	Groce R VERMONT YANKEE NUCLEAR POWER CORP.
To:	Grier R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
WVY-79-26, NUDOCS 7903140269
Download: ML19276E486 (15)

Text

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NI ..ID V ERMONT YAN KEE NUCLEAR POWER CORPORAT l'

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sCvCNTY ScVEN OROVC GTHCCT B.4.1.1 RuTi.Axo, WRF10NT 05701 REPLY TO; ENGINEERING OFFICE TURNPIKE ROAD WCSTDORO. M ass ACHUSETTS c15 81 T ELEP HCH E 617-366 90ll WVY 79-26 IIarch 1, 1979 United States Nuclear Regulatory Ccc=irsion Office of Inspection and Enforccnent Region I 631 Park Avenue King of Prussia, Pennsylvania 19406 Attention: Mr. Boyce H. Grier, Director Refcrence: License No. DPR-23 (Docket No. 50-271)

Subject:

Vertont Yankee 1978 Annual Report (2) copics of the Vercent Yankee Enclosed herewith please find tvo Annual Report, which describes the facility changes, tests, This and experitents report conducted without prior NRC approval during the year 1978.

is submitted in accordance with 10 CFR 50.59(b) .

Uc trust this information is acceptable to you; however, should you have any questions, please contact us.

Very truly yours, VE?JiONT YANKEE NUCLEAR POWER CORPCEATION W W -

Robert H..Groce Licensing Engineer RIIG/cm .

Enclosurc 790314O G f

I. Operations Summary A. Changes in Facility Design

1. The following changes requiring authorization from the Commission were made:

a) EDCR 74-26, Revision 1, Poison Spent Fuel Racks EDCR 74-26, Revision 1 received commission approval on September 15, 1977. It was submitted for PORC review on 1/26/78 and was completed on 4/20/78. t This EDCR covers the change in spent fuel storage capacity at Vermont Yankee from the existing 600 spent fuel assemblies to 2000 assemblies. Presently, Phasc I of the design change has been completed, and will accommodate 1230 spent fuel assemblics. This change was accomplished by using "Boral," neutron-absorbing storage equipment designed specifically for Vermont Yankee by Programmed and Remote System (par).

The spent fuel storage modules (racks) are fabricated from the following:

1) Castings Upper and lower grid structures cast from 356-T51 aluminum and final machined to meet dimensional re-quirements form the basic cavity locations, and support the cavity cans which hold the Boral poison curtain parts. The lower casting supports all the static and dynamic loads from the rest of the rack structure and stored fuel.

2) Side Plates Four (4) one-half inch thick, 6061-T651 aluminum-side plates bolt to the upper and lower castings forming the sides of the rack. These side plates maintain the proper dimensional relationship between the two castings and transfer all structural loads between the two.

3) Cavity cans A strip of neutron-abscrbing poison curtain material (Boral is positioned midway between each adjacent pair of spent fuel assemblies. This strip of Boral extends vertically one inch above and below the

active fuel in the spent fuel asscablies and is held in position by cavity can assemblies whose upper and lower ends are captured in pockets in the grid castings. These cavity cans are fabricated from two concentric square 5052-H32 aluminum tubes. The Boral is assembled in the void between the walls of the two aluminum tuber.

The ends of the outer tube are formed over, above and below the Boral, and welded to the inner tube, scaling the Boral in place between the walls of the cavity cans. These cans are placed in alternate cavity locations so that a given cavity storage location will be surrounded by either the four walls of a single cavity can or the individual walls of the four adjacent cavity cans.

4) Rack Feet Each rack rests on the spent fuel pool floor on five adjustable feet. The vertical adjustment is provided to enabic plumb and level installation and thus close proximity of adjacent racks in the presence of uneven-ness of the pool liner. These feet are 304 stainless steel at the liner interface insulated from the alumi-num machined parts uhich mate with the lower rack casting. This construction precluded concern over galvanic corrosion induced by a dissimilar metal couple at an aluminum / stainless steel interface.

These parts are all anodized prior to assembly to minimize corrosion. Assembly is accomplished, in special jigs to maintain tolerances, by bolting the side plates to the upper and lower castings and threading the feet into the lower castings.

Seismic design for this storage equipment is predicated on each individual rack being free-standing in the pool.

Analyses show they would slide and/or rock slightly under the most extreme seismic conditions postulated for this plant. No damage would be incurred by this action, and the clearances shown on the installation drawing will accommodate the sliding motion with acceptable margins.

PORC concludec that EDCR 74-26, Revision 1, does not pose any unreviewed safety question; it'does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

2. The following changes not requiring Commission approval were made:

a) EDCR 73-20, Supplement 6 - Reactor Building Crane EDCR 73-20, Supplement 6, was completed on 9/1/78.

This supplement provided the remaining documents requiring to complete EDCR 73-20; the FSAR page changes and the final drawing list. These docu-ments were not available in their completed forn until final NRC acceptance was received and all re-quired additional modifications completed. That acceptance was obtained and no further modifications are required.

PORC concluded that EDCR 73-20, Supplement 6, does not pose any unreviewed safety question; it does not increase the probability of occurrence or consequence of an accident previously analyzed, and it does not create the possibility of a different type of accident.

b) EDCR 77 V10-25 A&B Valve Motor Operator Modification EDCR 77-9 was completed on 7/14/78. This change provided for modification of the existing type SMB-3-100 Limitorque The operator to type SB-3-100 operators on V10-25 A&B.

modification added a belleville spring inertia pack to the Limitorque operator. This spring pack becomes part of the operator drive sleeve assembly and allows the stem This nut freedom of movement in one or both directions.

feature provided for the absorption of valve seating forces by compression of the springs rather than by tightening of the wedge in the seat; in effect, reducing thus reducing the the rigidity of the valve structure, buildup of the valve seat forces during the period follow-ing torque or limit switch opening.

PORC concluded that EDCR 77-9 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

c) EDCR 77 UPS Design blodification EDCR 77-19 was completed 9/22/78. This design change removed certain extraneous components and circuits from the UPS to alleviate established operating re-straints and impreve system reliability.

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1) The following trip fuactions were changed to alarm functions:

a. AC Overvoltage

b. AC Undervoltage (Fast)

c. Logic Failure

d. Leg Fuse Failure

e. DC Overvoltage

f. Leg Overtemperatures

2) Change the eutput circuit breaker to manual operation.

3) Remove output fuses.

4) Disable all power level and sync. circuits.

5) Disable photon coupler circuit.

6) Provide test points for DC volts, DC amps, and AC volts on front control panel.

7) Provide redundant logic power supply arrangement.

PORC concluded that EDCR 77-19 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequence of an accident previously analyzed, and it does not create the possibility of a different type of accident.

d) EDCR 77-22, Revision 1 - Vermont Yankee Torus Modification Work on EDCR 77-22, Revision 1, was completed in 7/78.

This design change adds two reinforcement pinto assemblies and two plain plates to each of the 32 columns. This modification is part of the Torus Support long-tern program, which assures the torus will withstand new loads discovered since the plant was constructed.

The plant is now operating under the short-term pro-gram criteria which is a . factor of safety of 2 on the torus-to-column welds. By the end of the long-tern program, these welds must meet ASME Section III, Sub-section NE requirements, which is a factor of safety greater than 4. This, plus new load combinations, make it necessary to increase the weld capacity by approximately 2h.

Although the final loads are not known, they have been bounded to where a torus-to-column weld design can be established with reasonable assurance that additional work will not need to be done when the Long-Term Program Final Load Definition Report is issued.

This work will be completed prior to the end of the LTP because all analytical efforts to keep the factor of .

safety greater than 2 have been exhausted. The NRC knows the strength of the welds and expects the fix to be made rather than waiting for the end of the Long- i Term Program lks to 2 years from now. t i

Work on EDCR 77-22 was terminated when cracks developed in the torus during gusset installation and a new con-tractor was chosen to repair the torus. This repair was performed under EDCR 78-17. A new EDCR will be ,

written in 1979 to cover a revised gusset installation procedure.

PORC concluded that EDCR 77-22, Revision 1, does not pose any unreviewed safety question; it does not increase the  ;

probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility f of a different type of accident.

e) EDCR 78 Permanent Fast Transfer Circuitry EDCR 78-03 was completed 10/2/78. This design change provided:

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1. The addition of an "early b" contact on the normal source breaker to initiate bus transfer. The "carly b" contact closes when the breaker starts to open; use of the "early b" contact to initiate the trans-fer assures that the normal source breakers will successfully trip before the transfer is completed.

2. The addition of a high-speed synchrocheck relay to supervise both high-speed transfers and manual trans-fers. Use of this relay will ensure that the transfer is blocked whenever there is an out-of-phase situation.

3. The addition of residual voltage relays to permit out-of-phase residual voltage bus transfer, but only after the voltage has decayed to a safe value.

PORC concluded that EDCR 78-03 does not pose any unreviewed safety question; it does not increase the probabilit3 ef occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

. 1 f) EDCR 78 Torus Repair EDCR 78-17 was completed 8/9/78. This design change repaired areas of the torus shell damaged during the implementation of EDCR 77-22. The torus shell was ground to remove all cracks as well as the heat-affected zones of the butter / temper pads. Cround areas were well repaired as necessary to provide a minimum torus wall thickness of no less than 0.48 inches. This leaves all torus areas with a factor of safety equal to or better than that accepted by the NRC as part of the Torus Short-Term Program.

PORC concluded that EDCR 78-17 does not pose any unreviewed safety question; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

g) EDCR 78-17, Revision 1 EDCR 78-17, Revision 1, was completed 8/9/78. This change to EDCR 78-17 resolves comments generated during the review of the design change. The comments were administrative in nature and were required to be satisfied prior to closecut of the Job Order File.

PORC concluded that EDCR 78-17, Revision 1, does not posc any unreviewed safety question; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

h) EDCR 78 RPS MG Set Modification EDCR 78-19 was completed 10/7/78. This design change replaced the existing over/under voltage protection for each MG set with a new solid state over/under voltage sensor and a new time-delay relay. The new over/under voltage device and the existing under-frequence relay was used with the time-delay relay to trip the MG set output circuit breaker after a time delay of approxi mately five seconds. The five-second time delay pre-vents unnecessary tripping due to transient conditions.

PORC concluded that EDCR 78-19 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

1) PDCR 77 LPCI Injection Valves V1025 A&B Redundant Automatic Openine Logic PDCR 77-4 was completed 7/14/78. This design change provided the installation of redundant contacts in the auto open logic for the inboard LPCI Injection Valve V10-25 A&B. This change ensures that both V10-25 A&B receives an automatic "open" signal in the event of a LOCA assuming a single failure of either logic train.

The existing relays that provide the redundant auto-matic open signal for the outboard LPCI Injection Valves V10-27 A&B have the necessary spare contacts to f acilitate this change. The relays selected for use, and the asso-ciated wiring comply with the technical description pro-vided in Proposed Change No. 21.

PORC concluded that PDCR 77-4 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

j) PDCR 77 RCIC Turbine Hydraulic Priming PDCR 77-6 was completed 7/19/78. This change provided the installation of an auxiliary oil sump in the oil supply line to the Woodward EG-R Hydraulic Actuator to climinate the possibility of starving the oil supply to the actuator during quick-start transients which can result in a turbine overspeed trip.

PORC concluded that PDCR 77-6 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident, k) PDCR 77 Supplement 1 - RCIC Turbine Hydraulic Priming PDCR 77-6, Supplement 1, was completed 7/19/78. This supplement to PDCR 77-6 is submitted to incorporate additional modifications to the HPCI and RCIC Hydraulic Piping that will allow addition of the auxiliary oil sump as described in the original PDCR.

PORC concluded that PDCR 77-6, Supplement 1, does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

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1) PDCR 77 Create a New Construction Joint on the Reactor Building East Wall PDCR 77-7 was completed 9/18/78. This change provided a new construction joint on the Reactor Building east wall. This was accomplished by saw cutting a one-inch by one-inch joint on the exterior f ace of the wall from 252'-6" elevation to the top of the concrete wall. The joint was then filled with a flexible backing and an clastomeric sealant on the outside.

PORC concluded that PDCR 77-7 oues not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

m) PDCR 77 Elinination of RWCU Flow Switch PDCR 77-9 was completed 7/28/78. This change provided for removal of flow switches and their replacement with a spool piece. PMR 77-20 addressed the electrical por-tion of the switches.

PORC concluded that PDCR 77-9 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

n) PDCR 78 Reactor Building Header & Standnine System t

PDCR 78-04 was completed 10/4/78. This change added a fire header and standpipe in the Reactor Building.

A supply header is provided in the torus area, fed by two independent sources of supply from the inner turbine fire loop. A new standpipe (with hose racks at each elevation above grade) is provided in the southeast area of the building. The existing stand-pipe in the northwest area of the building will be enlarged and fed by the new header. This will pro-vide adequate coverage of the Reactor Building with 75 feet of hose at each rack.

The header and standpipe system also provides a source .

of supply to the MG set foam syster at elevation 280',

and the cable penetration area sprinkler system at eleva-tion 232'.

PORC concluded that PDCR 78-10 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident, t) PDCR 78 Turbine Buildinn Loading Bay Sprinkler Systen PDCR 78-11 was completed 10/6/78. This design change provided an automatic sprinkler systen to protect the laydown area (loading bay) in the Turbine Building from a notor vehicle fire. This systen is intended to mini-nize the potential for large uncontrolled fires which could threaten the integrity of the Turbine Euilding.

PORC concluded that PDCR 78-11 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident, u) PAR 77 Addition of Fourth Service and Instrument Air Compressor PAR 77-9 was completed 4/20/78. This PAR provided for the addition of a fourth Service and Instrucent Air Compressor, changing of the cooling water piping to copper, and codificatica of the electrical controls.

PORC concluded that PAR 77-9 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

v) PMR 77 AEOG Test Switches _

PMR 77-19 was completed 7/14/78. This PMR provided for the addition of keylock test switches to isolate the selected channel AEOG trip logic during naintenance.

This change simplifies naintenance by avoiding lifting leads and placing jumpers to isolate the entire AEOG trip logic.

PORC concluded that PMR 77-19 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

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PORC concluded that PDCR 78-05 does not pose any unreviewed I safety questions; it does not increase the probability of l occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

p) PDCR 78 Recire. MC Set Foam Suppression System PDCR 78-7 was completed 10/11/78. This design change provided an automatic foam suppression system for the Recirc. - MG sets. This system provides exposure pro-tection for adjace.it reactor vessel instrumentation racks and safety-class cable trays.

PORC concluded that PDCR 78-7 does not pose any unreviewed safety questions; it does not increase the probability of  ;

occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

q) PDCR 78 Diesel Fire Pump Sprinkler System PDCR 78-8 was completed 9/25/78. This design change provided an automatic sprinkler system over the diesel fire pump area to provide exposure protection for the adjacent electric fire pump and service water pumps.

PORC concluded that PDCR 78-8 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

i r) PDCR 78 Diesel Generator Rooms A & B Manual Sprinkler Systen PDCR 78-9 was completed 9/19/78. This design change ,

provided manually operated sprinkler systems for each diesel generator room in order to prevent a fire in l one diesel generator room from affecting the operability of the other diesel generator.

8 PORC concluded that PDCR 78-9 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident, s) PDCR 78 Reactor Building Cable Penetration Area Sprinkler Svst_em PDCR 78-10 was completed 10/6/78. This design change provided an area preaction sprinkler system at the northwest corner of the Reactor Building to provided protection for redundant safety-related cables pene-trating the Reactor Building / Cable Vault walls.

w) PAR 77 Low Flow Trip for Reactor Water Cleanup Pumas PAR 77-20 was cenpleted 7/22/78. This PAR changed the instrunentation used in determining the low-flow con-dition. Sensor and indicating portions already exist, an alarn unit was installed to provide relay contacts in a logic sequence to an aux 1]iary relay. Annunciator nomenclature was changed to indicate a pump trip rather than a low flow. Annunciator indication was also changed because present circuitry actually indicates a pump trip for reasons in addition to low flow.

PORC concluded that PAR 77-20 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

x) PAR 77 Fire Protection Loop Isolation Valves PAR 77-23 was completed 9/24/78. This PAR provided additional isolation valves for the inside fire loop to allow for operational flexibility in the event of the loss of vital and non-vital hose stations.

PORC concluded that PAR 77-23 does not pose any unreviewed safety questions, it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident, y) PAR 77 Renoval of Acid Inlet Solenoid Valve on Makeun Denin, Systen PAR 77-26 was completed 4/5/78. The solenoid valve on the Makeup Demin. acid inlet line continually fails due to the acid environment to which it is exposed. This situation makes it necessary to override the valve, keeping it open, while isolating flow through the use of a nanual valve. Since the solenoid valve, when working properly, must be manually opened from the local control panel, removal of this valve does not create an operational probler.

PORC concluded that PAR 77-26 does not pose any unreviewed safety questions; it does not increase the prcbability of occurrence er consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident,

z) PAR 78 Reroute Domineralized 'Jater to Radwaste_

Monitor for Flushing PAR 78-4 was ccmpleted 5/31/78. This alteration changed the flushing supply for the Radwaste Discharge Monitor fron condensate water to demineralized water.

By using demineralized water as the flushing agent, the potential for an unmonitored release is decreased.

PORC concluded that PAR 78-4 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

sa) PAR 78 Stack Gas Lightning Protection PAR 78-7 was completed 10/13/78. This alteration re-duced lightning effects in the stack gas monitor cable by the installation of a new coaxial cable inside a continuous length of grounded steel conduit. Lightning protection is thereby achieved while maintaining noise immunity.

PORC concluded that PAR 78-7 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

bb) PAR 78 Stack Gas Isolation System Mechanical, Modification PAR 78-9 was completed 7/22/78. This alteration re-placed the solenoid valves on the stack filter drain line (SEI-107-2 A&B) with normally closed manual valves to provide necessary isolation conditions regardless of the electrical status of the stack valve dolenoid coils.

PORC concluded that PAR 78-9 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

cc) PA_R 78 Stack Gas Isolation Svstem Electrical Modification PAR 78-11 was completed 7/13/78. This alteration pro-vides for the removal of the SEI-107-2 ASB valves control cables frem the Stack Isolation Valve FCV-ll control circuitry (see PAR 78-09 above). This PAR prevents electrical failure of the solenoids from affecting the operability of FCV-11.

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PORC concluded that PAR 78-11 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accidcut.

dd) PAR 78 Removal of Press / Temp Instrumentation on Old A0G Line PAR 78-13 was completed 9/21/78. This alteration re-moves instrumentation and solenoids from an unused section of Off-Gas piping. By removing this instru-mentation, a source of spurious trips for the 516 A/B valves are eliminated as well as a possibic source of ignition for any hydrogen which may collect in this pipeline.

PORC concluded that PAR 78-13 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previosuly analyzed, and it does not create the possibility of a different type of accident.

ee) PAR 78 Addition of Keylock Switch to RMCS for Service Platform Interlock PAR 78-15 uas completed 8/4/78. This alteration pro-vided Control Room supervision of the refuel interlock associated with the service platform. In the past, a

" bypass plug" was installed in conjunction with the service platform power cabic prior to operating the platform. This new keylock switch eliminates the ne-cessity of the bypass plug without removing any pro-tection provided by that plug.

PORC concluded that PAR 78-15 does not pose any unrevieved safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

ff) PAR 78 Mod. of Turbine Steam Flow / Shutdown Level Recorder PAR 78-17 was completed 8/8/78. This alteration can provide continuous wide-range level indication in the Control Room whenever the reactor recirc pumps are at minimum speed by using existing instrumentation, speci-fically Recorder G-98 in CRP 9-5.

PORC concluded that PAR 78-17 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

gg) PAR 78 Diesel Fire Pump 011 Sample Connection PAR 78-19 was completed 4/18/78. This change adds a sample line and valve to the Diesel Fire Pump fuel line which will allow oil samples to be taken as re-quired Tech. Spec. Section 4.13.B.2.b.

PORC concluded that PAR 78-19 does not oose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident. I hh) PAR 78 Condensate Demin. Flow Balancinn Svstem >

Additions PAR 78-20 was completed 10/3/78. This alteration pro-vided an override system by inserting a flow balancing network on the master control output of the condensate demineralizer vessel during a high AP condition. This addition provides further protection against a loss of }

I flow downstrean of the Condensate Demineralizer System.

PORC concluded that PAR 78-20 does not pose any unreviewed  :

I safety questions; it does not increase the probability of eccurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.

ii) PAR 78 Air Compressor Flushing Connections PAR 78-35 was completed 11/27/78. This alteration pro-vided the ability to flush service water f r.a the air compressor cooling lines to prevent untreated service water from entering the TBCCW system in the event alter-nate cooling is required.

PORC concluded that PAR 78-35 does not pose any unreviewed safety questions; it does not increase the probability of occurrence or consequences of an accident previously analyzed, and it does not create the possibility of a different type of accident.