U-602587, Application for Amend to License NPF-62,allowing Removal of Inclined Fuel Transfer Sys Primary Containment Blind Flange While Primary Containment Required to Be Operable

Application for Amend to License NPF-62,allowing Removal of Inclined Fuel Transfer Sys Primary Containment Blind Flange While Primary Containment Required to Be Operable

ML20113E720
Person / Time
Site:	Clinton
Issue date:	06/28/1996
From:	Connell W ILLINOIS POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20113E723	List: ML20113E726 U-602587, Application for Amend to License NPF-62,allowing Removal of Inclined Fuel Transfer Sys Primary Containment Blind Flange While Primary Containment Required to Be Operable
References
L47-96(06-28)LP, L47-96(6-28)LP, U-602587, U-60587, WC-198-86, NUDOCS 9607080303
Download: ML20113E720 (14)

Text

___.-

Illinois Power Cornpany l

, Clinton Power Station

!, P.O. Box 678 Chnton. IL 61727 l

Tel 217 935-5623 l -* Fax 217 935-4632 l l

Wilfred Connell Vice President ILLIN915  ;

P6MR u-6025:2 L47-%( 06-28 )LP 8E.100a l

WC-198-86 l June 28, 1996 Docket No. 50-461 10CFR50.90 Document Control Desk Nuclear Regulatory Commission Washington, D.C. 20555 ,

i

Subject:

Clinton Power Station Proposed Amendment of  !

Facility Operating License No. NPF-62 (LS-96-006_)

Dear Madam or Sir:

Pursuant to 10CFR50.90, Illinois Power (IP) hereby applies for amendment of Facility Operating License No. NPF-62, Appendix A - Technical Specifications (TS), for i Clinton Power Station (CPS). This requests consists of a proposed change to the TS to  :

allow removal of the Inclined Fuel Transfer System (IFTS) primary containment blind flange while primary containment is required to be operable. This will provide flexibility ,

to operate the IFTS for the purpose of testing and exercising the system during such  ;

conditions. Primary containment integrity will be provided by an alternate means while the '

l blind flange is removed. The change would be effected by incorporating a provisional <

note into TS Surveillance Requirement (SR) 3.6.1.3.3, associated with TS 3.6.1.3,

" Primary Containment Isolation Valves (PCIVs)."

i I

A description of the proposed change and associated justification (including a l Basis For No Significant Hazards Consideration) are provided in Attachment 2. A marked-up copy of the affected pages from the current TS is provided in Attachment 3. A l rnarked-up copy of the affected pages from the current TS Bases is provided in

i. Attachment 4. Further, an affidavit supporting the facts set forth in this letter and its attachments is provided in Attachment 1. Following NRC approval of this request, IP will revise the CPS TS Bases, in accordance with the TS Bases Control Program of TS 5.5.11, to incorporate the changes identified in Attachment 4.

IP intends to implement this TS amendment just prior to the start of the sixth refueling outage, which is currently scheduled to begin on October 13,1996. As such, IP

! respectfully requests review and approval of this amendment by October 1,1996 to  !

I support such implementation..

J 9607080303 960628 '

ADOCK 050004 1 PDR p PDR R0k 080001 _

)g

i ,

U-602587 I

Page 2 IP has reviewed the proposed changes against the criteria of 10CFR51.22 for categorical exclusion from environmentalimpact considerations. The proposed changes do not involve a significant hazards consideration, or significantly increase the amounts or change the types of effluents that may be released offsite, nor do they significantly increase j individual or cumulative occupational radiation exposures. Based on the foregoing, IP l concludes that the proposed changes meet the criteria given in 10CFR51.22(c)(9) for a -

l categorical exclusion from the requirement for an Environmental Impact Statement.

l l Sincerely yours, Y $%W Wilfred Connell Vice President JFK/csm Attachments cc: NRC Clinton Licensing Project Manager q NRC Resident Office, V-690  :

Regional Administrator, Region III, USNRC Illinois Department of Nuclear Safety L

l s l 1

1 Attachment 1

. to U-602587 l

l l Wilfred Connell, being first duly sworn, deposes and says: That he is Vice President of )

Illinois Power; that the application for amendment of Facility Operating License NPF-62  ;

has been prepared under his supervision and direction; that he knows the contents thereof; and that to the best of his knowledge and belief said letter and the facts contained therein are true and correct.

Date: This Mday ofJune 1996.

Signed:

/

$A##

Wilfred Connell

,:::::::::::::::::::: =;

'OmCULSEAL' STATE OF ILLINOIS l SS. S hWdse

) mesy Suas elBull8 lujze COUNTY j c  % _O c::::::::::::::::: --

Subscribed and sworn to before me this 78 day ofJune 1996.

ouiAk C / so

/ p (NotaryPublfc)

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Attachment 2 to U-602587 j LS-96-006 Page1 of11 Backaround

System Description

l The Inclined Fuel Transfer System (IFTS) at Clinton Power Station (CPS) (Figure 1) is used to transfer fuel assemblies, control rods, defective fuel storage containers, and other small items between the pool in upper containment and the lower-elevation pool in the adjacent fuel building by means of a carriage traveling in an inclined transfer tube. The j IFTS is a 6xed installation, consisting of the inclined fuel transfer tube, upper and lower l upenders, hydraulic power units, an electrically powered winch, carriage, and l instrumentation required for the control system which includes redundant inputs for status l l indicators, and both a manual and semi-automatic programmable computer control facility. ]4

)

[ The transfer tube (Figure 1, Item 20) is a 23-inch ID stainless steel pipe, and provides a i

sealable, enclosed path for the carriage which is lowered and raised by means of a winch  ;

assembly. In the containment building pool (upper pool), the transfer tube connects to the l pool penetration and to a sheave box. The position of the carriage in the tube is tracked l by a calibrated position system. The transfer tube is suspended between two flexible seals, l or bellows. The transfer tube includes a valve at both ends, and is provided with a primary containment isolation assembly. The valve at the upper end, known as the flap valve (11),

consists of a 24-inch disc with an actuating cylinder (12) and is mounted on the sheave ,

box (14). The lower end has a 24-inch hydraulically operated gate valve (25).

The sheave box (14) is a multipurpose device that not only provides a means to open and close the end of the transfer tube by use of the flap valve (11), but also connects the two i winch cable enclosure pipes (5), the vent pipe (4), and the fill valve (13). The vent pipe i has a fluid stop (3) connected to the containment building ventilation system that prevents air displaced by refilling the transfer tube from entering the containment building -;

atmosphere, and which confines the water surge to the pool water The sheave box also encloses the cable sheaves which keep the twin cables from the winch in proper parallel l

alignment with the carriage. Just below the sheave box, a hand-operated 24-inch gate  !

valve (17) is provided to isolate the upper pool water from the transfer tube so that the

! containment isolation assembly can be disassembled or reassembled.

l The containment isolation assembly consists of two pipe spools separated by a removable blind flange (18) which is connected to the containment building penetration via a flexible metal bellows (19). The blind flange normally forms part of the primary containment boundary. Before the IFTS can be placed in operation, the containment isolation assembly must be disassembled and the blind flange replaced with a gasketed ring, and reassembled.

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Attachment 2 to U-602587 LS-96-006 1 Winen Page 2 of11 ,

2 Hydroulic Power Supply I 3 Fluid Stop 4 Vent Pipe 5 Winch Coble Enclostre Pipes 6 Horizontal Guide Arms T Upper Pool Uponder 8 Hydraulle Cylinder 9 Hydraulle Cylinder 1

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10 Upper Pool framing 3 /" ~ '

Flop Volve T."T V_"

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12 Hydraulic Cylinder *.*

v/CONTAINMENTBLOC.

FUEL TRANSFER POOL STEEL CONTAINMENT h 4 e 13 Fill Valve (1F42-F001) (

14 Sheave Box 5 . , , * ...

15 Prinary Cantolnment Penetration Sleeve e.. 7 ***

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16 Hydraulic Cylinder . d. 6 .

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IT Manual Cote Volve (1F42-F002) .*.

18 Primary Containment Bilnd Flange

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1. r10 19 Containment Bellove

• 20 Transfer Tube * -

Hydraulle Power Supply .** . 14

• 21 22 Widsupport a;

h'4 131, , .

9 12 m 23 Wire Rope (Cables) *.,.

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24 Carrtoge #*

24A Tilt Tube 16 " .

248 Follower 2, 25 Cote Volve (IF42-F004)  ;*

Nw1T 26 Be: lows *,, N' 18

' 19 27 Drain Volve (1F42-F003) ,

15 28 Horizontal Guide Arms . . .. s ; g 29 Volve Support Structure g ,T

. ' . **.* , ,,, .' ' f, 30 Lower Pool Froming * '

Lower Pool Uponder f i, , , *

, J 31 32 Pivot Arm Froming *

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/ FUEL 22 # *

. *I, BUILDING a

• o NORMAL WATER LEVE,L ~

ELEY. T54'-O' v - ,0. *

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• FUEL BLOC. FUEL '*

• TRANSFER POOL

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DRAIN

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4 PIPE 24

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• DRAIN TO FC 8 i SURGE TANK

- 26 1F42-F301 VALVE OUTLET REF. ELEV. T28'-11'

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31 3 p 30 8 -

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Attachment 2 l j , to U-602587 i

LS-96-006 Page 3 of 11 The spring hanger and snubbers (22) at the mid-section of the transfer tube provide i support and seismic restraint for the sy: tem. At the connection of the two transfer tube

j. sections, the 4-inch drain line and the " tube-drained" liquid level sensors are installed.

L I The drain line contains an automatic isolation valve (27) and provides a means oflowering the water level in the transfer tube prior to transferring the carriage and its contents to the

lower pool. Water drained out of the transfer tube is directed to one of the Fuel Pool  ;

! Cooling and Cleanup System surge tanks where it is reintroduced to the pool systems. i While draining, the transfer tube is vented to the containment building atmosphere through the vent pipe (4) attached to the sheave box at the top of the transfer tube. The winch cable enclosure pipes (5) attached to the sheave box provide a path for the winch to raise ,

and lower the carriage within the transfer tube while preventing upper pool water from )

l entering the drained transfer tube.

In the lower pool, a bellows (16) connects the pool wall penetration to the 24-inch hydraulically operated gate valve (25) and to the transfer tube, thus preventing water entrapment between the transfer tube (20) and the lower pool penetration sleeve while still allowing axial movement of the transfer tube. Transfer tube axial movement is required to allow the installation and removal of the blind flange near the upper end of the transfer tube. The transfer tube lower valve (25) is cradled within a valve support stmeture (29) in the lower pool.

A hydraulically operated upender (7, 31) is located at each end of the transfer tube in the upper and lower pools, respectively. These devices contain a short section of track for guiding the carriage and are mounted on pivot arms which permit them to be rotated to a vertical position for loading and unloading the carriage. The upenders are similar in constmetion and perform identical functions. Each upender has guide arms that provide support and guidance for the carriage during the tilting motion of the upper section of the ,

carriage. Framing within each of the pools provides support for the upender and actuating hydraulic cylinder. Proximity sensors are mounted to the framing to detect both the vertical and the inclined positions of the upender.

The carriage (24) is a wheeled, articulated, tubular, device consisting of two sections

- hinged together. Carriage alignment is maintained by following a track welded to the inside of the transfer tube and on each of the upenders. The upper section of the carriage (tilt tube,24A) is coupled to the lower section (follower,24B), by means of a pivot assembly. The tilt tube is designed to accept two different inserts - a fuel bundle insert with a two-bundle capacity and a control rod insert for control rods, defective fuel storage container, and other small items. When the upenders are raised to a vertical position, the

' tilt tube (24A) rotates with the upender while, the follower (24B) remains inclined on the track. Both sections of the carriage, the tilt tube and the follower, are fitted with wheels.

, Center guide wheels provide lateral alignment with the vertical spur of the transfer tube i

I

r Attachment 2

, to U-602587 LS-96-006 Page 4 of11 track. The carriage assembly wheels also provide rolling support for the carriage by l transferring the weight of the carriage and its cargo, through the track flange, to the

! transfer tube. For raising and lowering the carriage, the follower has a pivot bar assembly

! where the winch tables are attached, one on each side, A winch (1), located on the containment refueling floor, uses two cables attached to the lower end of the follower (24B) for pulling the carriage from the fuel building to the containment building and for controlling the carriage descent velocity. A slow winch speed is provided for starting and stopping the carriage to limit the acceleration on the fuel assemblies. Cable underload and overload protection is provided by a load cell. Carriage

! position readout is also provided. . Cable enclosure pipes (5), attached to the sheave box (14) and projecting above the containment upper pool water level, provide the means for cable exit from the transfer tube while isolating pool water from the transfer tube when it is in the drained condition.

Control panels are provided in close proximity to each transfer pool area and are connected for voice and interlock communication. The containment and fuel building panels have control buttons for actuating their respective upender, a button for initiating the transfer sequence to the other building, and a stop button. The transfer operation functions on an automatic basis with a provision made for manual override. Automatic sequencing is accomplished by use of an electronic controller located in the fuel building which utilizes sensors for confirming the successful completion of each step before initiating the next step. The completion of a transfer sequence is signaled at the control

panels.

l Interlocks assure the correct sequencing of the transfer system components and fuel handling equipment during automatic or manual override operation. Interlocks prevent the refueling platform from moving into the containment building transfer area unless the upender (7) is in the vertical position, and prevent upender movement if the platform is already in the transfer area. Likewise, interlocks also prevent the fuel handling platform from moving into the fuel building transfer area unless the upender (31) is in the vertical position, and prevent movement of the upender if the platform is in the transfer area.

System Operation The operational sequence for the fuel transfer system (Figure 1) is described as follows.

As a starting point, assume the carriage (24) is in the containment transfer pool with the l tilt tube (24A) supported by the upender (7) in the inclined position. In this position, the flap valve (11), the fill valve (13) and manual gate valve (17) are open with the bottom gate valve (25) and drain valve (27) closed. The operational sequence is as follows:

a. The hydraulic cylinder (9) is actuated to push the upender and tilt tube (7 and 24A)

( to the vertical position.

Attachment 2 to U-602587 LS-96-006 Page 5 of11

b. Control rods or other items are loaded into and removed from the tilt tube.

c. The hydraulic cylinder (9) is actuated to pull the tilt tube into the inclined position for transfer,

d. The automatic operation is started by depressing the transfer button on the containment control panel. This starts the winch (1) unwinding the cables to lower the carriage (24).

e. The carriage is stopped approximately 2 feet above the bottom gate valve (25).

f. The flap valve (11) and fill valve (13) are closed.

g. The drain valve (27) is opened and water is drained to the level of drain pipe attachment to the transfer tube (20). During the draining process, air is admitted to the transfer tube through the vent pipe (4) and the cable enclosures (5). The final level of water inside the transfer tube will be equal to the water level of the fuel building transfer pool if containment building atmospheric pressure is equal to the atmospheric pressure of the fuel building.

h. The bottom gate valve (25)is opened.

i. - The winch lowers the carriage until it is stopped and supported by the pivot arm f framing (32).

j. The hydraulic cylinder (8) is actuated to push the upender (31) and tilt tube (24A)  :

to the vertical position. '

k. The cargo is loaded or unloaded as needed.

1. The hydraulic cylinder (8) is actuated to lower the tilt tube (24A) and upender (31)  !'

to the inclined position.

m. The winch (1) is actuated by depressing the fuel building control panel's transfer .

button and pulls the carriage (24) to a position approximately 2 feet above the bottom gate valve (25) where it is automatically stopped.  ;

i

n. The bottom gate valve (25) and drain valve (27) are closed.  !

j o. The fill valve (13) is opened and transfer tube filled.

i

p. The flap valve (11) is opened when sensors indicate that the transfer tube (20) and

vent pipe (4) are filled with water.

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l Attachment 2

, to U-602587 LS-96-006 Page 6 of11

q. The carriage is pulled to the containment transfer pool (staning point).

After transfer operations are completed, the carriage is stored in the containment building pool on the upender (7). Containment isolation is effected as follows:

l'

a. The manual gate valve (17)is closed.

l b. Bolts are removed from the containment isolation assembly as required to allow ,

l insertion of the blind flange (18).

c. The transfer tube (20) is lowered with the hydraulic cylinders (16).

d. The blind flange is inserted and bolts are installed.

e. The transfer tube is pulled up with the cylinders (16).

f. The bo!ts are tightened and the pressure on the cylinders (16) is relieved.

With respect to the IFTS and its associated containment penetration, containment operability is made by the blind flange (18), containment bellows (19), and the steel core tainment penetration. Special gaskets are provided for leak checking to assure containment isolation. )

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To date, isolation of the IFTS containmeni pcnctration hn only been 9tisfied (durmg i applicable operating modes) with the above-described configuration. However, in lieu of j this configuration and as fudher described below, Illinois Power (IP) has identified an 1 alternate means to provide adequate isolation of the IFTS containment penetration that would permit the IFTS blind flange to be removed during applicable plant operating modes, provided that certain conditions are met.

Description of Proposed Change In accordance with 10CFR50.90, IP proposes a change to Technical Specification (TS) 3.6.1.3, " Primary Containment Isolation Valves (PCIVs)," to add a Note to SR 3.6.1.3.3, stating: "Not required to be met when the Inclined Fuel Transfer System (IFTS) primary containment blind flange is removed, provided that the fuel building fuel transfer pool water level is maintained 2 el. 753 ft and the IFTS transfer tube drain valve (s) remain (s)

~ closed, except that the IFTS tube drain valve (s) may be opened under administrative

controls."

The proposed TS change is reflected on a marked-up copy of the affected page from the

, CPS TS contained in Attachment 3. In addition, changes to the CPS TS Bases, consistent with the TS change proposed above, have been provided in Attachment 4.

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! Attachment 2 to U-602587 LS-96-006 Page 7 of 11 l

Basis and Need for Proposed Change The portion of the IFTS which forms a part of the primay containment boundary contains a flexible metal bellows and a removable blind flange near the upper end of the transfer tube. This flange must be removed to permit the carriage to travel between the upper and lower pools. Since this blind flange forms part of the primary containment bounday, breaking its connection to the flexible metal bellows is a breach of primay containment integrity and is currently only permitted when the reactor is in a mode when primary containment operability is not required (i.e., not in Modes 1, 2, or 3).

As with any complex and intricately interlocked system that is left idle for an extended period of time, good engineering practice dictates an inspection and exercise of the IFTS prior to operating it in continuous duty during a refueling outage. Due to the high degree of system and domponent complexity, a satisfactory check of the entire system, including any subsequent adjustment of sensors or system repairs, can take several days. The duration of this evolution often creates a hardship since such system testing can commence only after primary containment integrity is no longer required, i.e., when the blind flange can be removed. This has caused IFTS start-up operations to be a " critical path" activity during past refueling outages as CPS.

As indicated previously, IP has identified an alternate means to ensure isolation of the IFTS containment penetration in lieu of having the IFTS blind flan 8e in place. This ^

alternate means takes credit for the fact that the IFTS transfer tube terminates deep in the fuel building fuel transfer pool, effectively sealing the tube and precluding it from becoming a potentialleak path of the containment atmosphere (into the fuel building) in the event of a design basis accident. This provides a basis for permitting the flange to be removed to support IFTS testing during plant operation (typicallyjust prior to plant shutdown for a refueling outage) provided that certain conditions are met, as further i described below.

Justification for Proposed Change The design basis for the primary containment is to maintain its integrity following the instantaneous rupture of the largest single reactor coolant system pipe within the structure, while also accommodating the dynamic effects of the pipe break coincident with a safe-shutdown earthquake. This is accomplished by designing, purchasing, and installing systems and components in accordance with applicable codes, standards, and regulatory requirements.

l The result of allowing the IFTS blind flange to be removed when primary containment i operability is required is to potentially subject additional ponions of the IFTS to the conditions existing in a post-accident environment. The IFTS design specification does j not require the entire system to meet the requirements necessay for certification as a

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Attachment 2

, to U-602587 l l . LS-96-006

] Page 8 of 11 l

! i f i j primary containment boundary. While much of the system may not be built to the

standards tied to bona fide primary containment boundary components (ASME, 3 Section III, Class 2), it is nonetheless built to withstand the rigors of a commercial nuclear  !

i application (ANSI B31.1). This includes, but is not limited to, consideration of adequate

! - seismic support, inertial forces imparted to the fuel, appropriate cooling and shielding for

, the spent nuclear fuel, integrity of the fluid system pressure boundaiy, and a safety  :

analysis, including a failure modes and effects evaluation which assumes that credible i events and credible combinations of events have been considered and mitigated against by i either a fail safe design or redundancy. I j Although continually water sealed by the fuel building fuel transfer pool, an open IFTS l

transfer tube constitutes a potential leakage pathway from the containment building to the  !

j fuel building. Since the outlet of the transfer tube has a submergence depth greater than i j the containment building peak calculated accident pressure, the post-accident containment i building atmosphere will not have direct communication with the fuel building atmosphere.

l The peak calculated containment internal pressure for the design basis loss of coolant i accident (Pa) is 9.0 psig. An equivalent head of water (conservatively taken to be at atmospheric pressure and saturated conditions)is:

95 in' s 144 -

0.016719 = 21.668 ft ft's < lb >

Normal water level elevation in the fuel building fuel transfer pool is 754' - 0". This is maintained by the Fuel Pool Cooling and Cleanup System (FC). During FC operation the water level in this pool will not be reduced below this elevation since the fuel building l pools do not have any drain connections that are lower.

l An examination of constmetion and installation drawings was performed to determine the elevation of the transfer tube outlet valve (IF42-F004). These drawings document the centerline of the outlet flange to be at an elevation of 728'- 4 9/16" (or 728.38 ft). Since the transfer tube is installed at a 31 angle from the vertical, the top of the valve outlet flange will be slightly higher than the centerline of the valve outlet flange. A trigonometric calculation shows the high point of the 24-inch diameter valve outlet flange to be at elevation 728'- 10 3/4" (or 728.895 ft). The ncrmal submergence of the highest point on the transfer tube outlet is therefore:

754 ft -728.895 ft = 25.105 ft This creates a submergence margin of; 25.105 ft-21.668 ft = 3.437 ft

Attachment 2 l l

to U-602587 I LS-96-006 Page 9 of11 Thus, it is clear that the static head provided by the fuel building transfer pool water is l sufficient to prevent the open communication of containment building atmosphere to the fuel building atmosphere, even at the peak calculated accident pressure.

There is, however, one point in the operation of the IFTS where the water seal created by the lower pool could be potentially bypassed. When the transfer tube is in the drained i condition, the vent pipe at the sheave box connects the containment building atmosphere to the FC surge tank piping in the fuel building, via the transfer tube drain line. A vent path from the containment building to the transfer tube is also created when the bolting is temporarily loosened during removal of the blind flange. These evolutions are relatively short in duration and administrative controls will be in effect to ensure that transfer tube drain line can be rapidly isolated via closure of manual valve IF42-F301. The use of administrative controls to intermittently open valves that are closed for the purpose of  ;

isolating containment penetrations is already acknowledged in the Technical l Specifications, i.e., in the Notes associated with the Surveillance Requirements and  !

Actions under TS 3.6.1.3. Per the TS Bases description for the Actions associated with LCO 3.6.1.3, these administrative cor.trols consist of stationing a dedicated individual at the controls of the valve, who is in continuous communication with the control room. In this way, the penetration can be rapidly isolated when a need for primary containment i isolation is indicated. I Effective primary containment isolation will thus be provided for all modes of system operation. Additionally, in the unlikely event that a portion of the containment building atmosphere were to be introduced to the fuel building, it would be contained within the boundaries of secondary containment and filtered by the Standby Gas Treatment System prior to release to the environment.

Basis For No Significant Hazards Considentip_o According to 10CFR50.92, a proposed change to the operating license (Technical Specifications) involves no significant hazards consideration if operation of the facility in accordance with the proposed change would not: (1) involve a significant increase in the probability or consequences of an accident previously evaluated, or (2) create the possibility of a new or different kind of accident from any accident previously evaluated, or (3) involve a significant reduction in a margin of safety. The proposed change is evaluated against each of these criteria below.

(1) The proposed change allows operation of the IFTS while primary containment l operability is required. The proposed change does not involve any modifications j to plant systems or design parameters or conditions that contribute to the initiation l of any accidents previously evaluated. Therefore, the proposed change cannot increase the probability of any accident previously evaluated.

l

Attachment 2 to U-602587 LS-96-006 l Page 10 of11 i i

! 1 i The proposed change potentially affects the leak-tight integrity of the containment L structure which is designed to mitigate the consequences of a loss-of-coolant l accident (LOCA). The function of the primary containment is to maintain functional integrity during and following the peak transient pressures and temperatures that result from any LOCA. The primary containment is designed to i limit fission product leakage following the design basis LOCA. Because the proposed change does not alter the plant design, only the extent of the boundaries that provide primary containment isolation for the IFTS penetration, the proposed change does not result in an increase in primary containment leakage. However, temporarily using the IFTS transfer tube and its attached appurtenances as part of the primary containment boundary (which have not been fabricated or installed to exactly the same requirements as a fully certified primary containment penetration) can increase the probability that a LOCA would challenge the pressure retaining integrity of these components. Since the subject components have been built to withstand pressure, temperature, and seismic conditions similar to those of the existing penetration, they arejudged to be an acceptable barrier to prevent the uncontrolled release of post-accident fission products for the purposes of this amendment request.

Further, it has been shown that the largest potential leakage pathway, the IFTS

! transfer tube itself, would remain sealed by the depth of water required to be maintained in the fuel building fuel transfer pool. The transfer tube drain line constitutes the other possible leakage pathway, and will be required to be capable of being isolated via administrative control of the manual isolation valve in the drain line. Additionally, due to the physical relationships of the buildings and components involved, any leakage from either of these pathways is fully contained  ;

within the boundaries of the secondary containment and would be filtered by the l Standby Gas Treatment System prior to release to the environment.

Based on the above, IP has concluded that the proposed change will not result in a significant increase in the probability or consequences of any accident previously  !

evaluated.

(2) The proposed change does not involve a change to the plant design or operation ,

(except when the IFTS is operated). As a result, the proposed change does not affect any of the parameters or conditions that could contribute to the initiation of any accidents.~ No new accident modes are created by this change. Extending the primary containment boundary to include portions of the IFTS has no influence on,

( nor does it contribute to the possibility of a new or different kind of accident or

, malfunction from those previously analyzed.

Based on the above, IP has concluded that the proposed change will not create the

, possibility of a new or different kind of accident not previously evaluated.

~

Attachment 2 to U-602587 LS-96-006 Page11 of11 (3) The request does not involve a significant reduction in a margin of safety. The proposed change only affects the extent of a portion of the primary containment boundary. Precautions will be taken to administratively control the IFTS transfer tube drain path so that the proposed change will not increase the probability that l

an increase in leakage from the primary containment to the secondary containment could occur.

The margin of safety that has the potential of being impacted by the proposed change involves the offsite dose consequences of postulated accidents which are directly related to containment leakage rate. The containment isolation system is designed to limit leakage to L., which is defined by the CPS Technical Specifications to be 0.65% ofprimary containment air weight per day at the calculated peak constant pressure (P,). The limitation on containment leakage rate is designed to ensure that total leakage volume will not exceed the value assumed in the accident analyses at the peak accident pressure (P,). The margin of safety l for the offsite dose consequences of postulated accidents directly related to the containment leakage rate is maintained by meeting the 1.0 L, acceptance criteria.

The L, value is not being modified by this proposed Technical Specification change. The IFTS will continue to provide an acceptable barrier to prevent containment leakage during a LOCA, and therefore this change will not create a situation causing the containment leakage rate acceptance criteria to be violated.

As a result, IP has concluded that the proposed change will not result in a reduction in a margin of safety.

Based on the foregoing, IP concludes that this proposed change does not involve a significant hazards consideration.

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