ML20138A486

Application for Amend to License SNM-1227,providing Summaries of Criticality SAs for Rod Fabrication,Bundle Assembly,Line 1 Process Offgas Sys & Line 2 Pog

ML20138A486
Person / Time
Site:	Framatome ANP Richland
Issue date:	04/15/1997
From:	Edgar J SIEMENS POWER CORP. (FORMERLY SIEMENS NUCLEAR POWER
To:	Chotoo S NRC OFFICE OF NUCLEAR MATERIAL SAFETY & SAFEGUARDS (NMSS)
References
JBE:97:050, JBE:97:50, NUDOCS 9704280087
Download: ML20138A486 (43)

Text

79()$

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SIEMENS April 15,1997 J8E:97:050 U.S. Nuclear Regulatory Commission Attn: Ms. Susan Chotoo Licensing Branch Division of Fuel Cycle Safety and Safeguards, NMSS Washington, DC 20555

Dear Ms. Chotoo:

Enclosed for your information and to include in Chapter 15 of Siemens Power Corporation's (SPC) license application are six copies each of pages 15-34 through 15-34f,15-35 through 15-35e,15-36 through 15-36d, and 15-37 through 15-37d. These pages provide summaries of criticality safety analyses, respectively, for rod fabrication, bundle assembly, Line 1 process offgas (POG) system, and Line 2 POG system.

If you require additionalinformation, please call me at 509-375-8663.

Very truly yours, JameY B. Edgar Staff Engineer, Licensing

/pg Enclosures 9704290087 970415 PDR ADOCK 07001257 C

PDR g.

ll ll ll ll ll Ill lll 4

Siemens Power Corporation Nuclear Division 2101 Horn Rapids Road Tel:

(509) 375 8100 j

Engineering & Manufacturing P.o. Box 130 Fax:

(509) 375 8402 k

Richland, WA 99352-o130 L

. Siemens Power Corporation - Nuclear Division eur.2

)

SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 PART ll-SAFETY DEMONSTRATION REv.

15.1.10 Rod Fabrication 15.1.10.1 fLqd Loadina The rod loading process consists of three hoods in Room 182 in which the finished pellets are inserted into previously lower end welded zirconium cladding. Outgas trays, after i

leaving the pellet outgas system, enter one of the three hoods where the pellets are l l

removed from the trays, placed into a pellet trough, and pushed into a fuel rod. The major j i

system components are manual and automatic rod loading hoods and the rod handling l system.

i 15.1.10.1.1 Criticality Safety I

{ The rod loading process relies on both administrative and engineered controls on i geometry, on moderator control, and on the presence of neutron absorbers (steel in the l pellet outgas trays) for criticality safety. The manual and automatic rod loading equipment j have been evaluated and are acceptable.

Manual Rod Loadina Hoods Criticality safety in manual rnd loading hoods is maintained by controlling the pellet outgas i

tray stacks to 10 trays high and in an end-to-end configuration, by limiting the depth of pellets on the floors of the hoods to 3.6 inches maximum, by using self-draining equipment (trays, etc.) or keeping significant quantities of water out of the hoods, and by the design of the outgas trays to ensure a minimum steel mass of 2.5 kg for neutron absorption.

Summarv of Accident Conditions l The evaluation of the manual rod loading hoods considered a number of possible upset l conditions simultaneously. These included overstacking of all outgas tray stacks (17 trays high - the maximum stack height that will fit through the hood entry portal) within the hoods, having a 3.6 inch deep layer of pellets covering !.he floors of the hoods, optimizing the amount of moderator throughout the hood, and havirs fuli water reflection on all sides of the hood. With these simultaneous upsets, the manual rod loading hoods are still i

adequately subcritical, i.e. k,is less than 0.95.

l

• Automatic Rod Loadina Hoods l The automatic rod loading hoods have a different design from manual hoods. Instead of a row of end-to-end outgas trays, the automatic hoods have five sets of rollers set side-by-l side with a 4 %" spacing between tray stacks maintained by the p3!!ets. These five sets of j rollers are moved as a group from side-to-side which allows each of the roller sets to be loaded with a stack of outgas trays.

r AWENOWENT APPLCATION DATL PAGE NO.:

April 15,1997 15-34 SPc-NO.3330 947 (R-UO7 92)

~

9 Siemens Power Corporation - Nuclear Division eur.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 PART ll-SAFETY DEMONSTRATION REV.

Criticality safety in the automatic rod loading hoods is maintained by controlling the pellet outgas tray stacks to 10 trays high, a maximum of 5 stacks in side-to-side configuration, by limiting the depth of pellets on the floors of the hoods to one inch maximum, by using self-draining equipment (trays, etc.) or keeping significant quantities of water out of the hoods, and by the design of the outgas trays to ensure a minimum steel mass of 2 5 kg for neutron absorption.

l i

l Summary of Accident Conditions The evaluation of the automatic rod loading hoods considered a number of possible upset conditions simultaneously. These included overstacking of all outgas tray stacks (15 trays I high - the maximum tray stack height that will fit through the hood entry portal) within the l l rod loading hood, having a full (one inch deep) catchpan of pellets on the hood floor, optimizing the amount of moderator throughout the hood, and having full water reflection on all sides of the hood. With these simultaneous upsets, the automatic rod loading process is still adequately subcritical, i.e. k,is less than 0.95.

i Rod Handlina e

Rods are handled in the rod loading area in two different ways. The first is during the process of loading pellets into the rods and the second is after loading is complete. During i

l complete, the rods are placed on a single-tier plane where the upper end loading, the rods are cycled through a sloped multi-tiered set of planes. After loading is l l

j in place and are eventually transported to the rod testing process.

! Criticality safety in the multi-tiered rod handling equipment depends upon controlling the l total number of rods (to 150 maximum) and the depth of the rods per layer (one rod deep).

, After loading, the rods are limited to a single tier maximum slab thickness of 3.6 inches which is 85% of a minimum critical slab thickness. Also the rod handling equipment is free draining.

Summarv of Accident Conditions The evaluation of the multilevel rod handling process considered combinations of the upset conditions of double batching the allowed number of rods and doubling the number of rods per level. With these upsets and full flooding, the process has a maximum k, of 0.85, which is subcritical by a large margin. In the single level handling system, even though the slab thickness limit is 3.6 inches, the rods are handled as a single rod layer of rods and the handling equipment will not allow more than one rod deep.

AMEh0 MENT APPUCATON DATE:

PAGE PC:

April 15,1997 15-34 a SPC-ND 3330 947 (R 1<07$2)

. Siemens Power Corporation - Nuclear Division eur.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 PART 11 - SAFETY DEMONSTRATION REv.

15.1.10.1.2 Radiation Protection Rod loading is performed in a low surface contamination controlled area. This area is operated at a pressure slightly below atmospheric to preclude egress of airbome contamination.

Sintered, ground and washed pellets do not pose problems with generating airbome contamination.

l 15.1.10.1.3 Ei.re Protection The UO building is rated as noncombustible. Fire loading is kept to a minimum through 2

monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat !

2 detectors are strategically placed throughout rod loading area. Where moderation control l

is in place, high expansion foam, dry chemical or CO are required to be used to combat a 2

fire.

All flammable and combustible liquids of greater than one pint in volume used in the l process are stored in fire rated containers.

15.1.10.1.4 Environmental Safety j

The concrete floors are sealed to be liquid tight and contain no floor drains. Room 182 is serviced by a "once through" HVAC system that is continuously monitored for radioactive contamination. The exhaust systems for Room 182 are double HEPA filtered and have j

j deluge systems to protect the final filters from fire.

l' 15.1.10.2 Rod Testina The rod testing equipment is located in Room 189 of the UO Building. The following 2

I pieces of equipment are included:

1)

The horizontal leak check station which checks for any intemal leakage from the rod which would indicate a possible incomplete weld or cladding pin hole, 2)

The AFRAS station which checks enrichment uniformity and pellet and i

plenum length measurements; 3)

The X-ray station which checks for any abnormality within the weld and l

plenum areas; and 4)

Associated equipment such as transfer carts, transfer vehicles and conveyors used to move groups of rods.

i AMENOMENT APPLCATON DATE:

PAGE NO :

l April 15,1997 15-34 b i

SPC-NO 3330 947 (R+0742)

T Siemens Power Corporation - Nuclear Division eus.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 PART 11-SAFETY DEMONSTRATION nev.

1 15.1.10.2.1 Criticality Safety 1

The rod testing process relies on geometry control; specifically, that slab thickness not

{

exceed 3.6 inches. It is further required that all equipment be free-draining to prevent water from accumulating in the interstitial spaces between the fuel rods and that no extraneous plastic be stored or used around or between the fuel rods.

. All Eauioment i

The rods which are contained in process trays are transferred to and from the testing-l equipment via transfer carts. Each of the carts can transfer two process trays, which are - l

' approximately 15 inches on horizontal center. The infeed to the horizontal leak check l station consists of a three tiered conveyor with the middle section at the same elevation as ;

i the leak checker. Each of these levels (approximately 15 inches vertical center) can hold l

two trays end-to-end.

j l

l The leak check station holds a maximum of one tray for testing purposes. In line with the

. exit of the station is a two tray (side-by-side as described previously) transfer cart for l transfer of the rods from the process trays to the AFRAS station. The AFRAS station ;

i l

holds a single level of rods side-by-side. The exit of the AFRAS transfers two levels of rods (approximately 10 inches on vertical center) into a single level which then roll on an !

i l..

inclined conveyor to the X-ray station infeed assembly. Approximately 150 rods maximum ;

can be contained on this inclined conveyor.

l l

4 i

The X-ray handles 25 rods at a time in a single level. These rods, after being X-rayed, are.

loaded back onto the process trays and transferred to rod storage via a four-tiered l r

conveyor system.

l

{

Because criticality safety is dependent upon maintaining a maximum slab depth of 3.6 inches, the design of the rod trays and conveyors ensures that this depth will not be exceeded. The design also ensures that the trays and conveyors are self-draining.

l Summary of Accident Conditions l

l

}

[

Overstacking of rods was evaluated. Under optimum moderation and full water reflection r

conditions k, for 0.30 inch diameter rods on a square pitch of 1.30 cm (most reactive array) for a 4.2 inch deep slab (minimum critical slab thickness) was 0.98. In fact, gravity 4

will cause the rods to settle into a triangular pitch touching each other, which is less reactive. The minimum critical slab depth for close packed rods is in excess of six inches.

h a

i AMENOMENT APPLCATON DATE:

PAGE NO.:

April 15,1997 15-34c l

SPC-ND:3330.947 (R 1/07/92) 4

..c i

. Siemens Power _ Corporation - Nuclear Division.

eup.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 l

]-

PART 11 -SAFETY DEMONSTRATION REV.

j i

1 15.1.10.2.2 Radiation Protection Rod testing is performed in a low surface contamination controlled area. This area is operated at a pressure slightly below atmospheric to preclude egress of airborne contamination. At the rod testing station the pellets are sealed in zirconium cladding so do not generate airbome contamination.

15.1.10.2.3 Fire Protection l

1 t

The UO building is rated as noncombustible. Fire loading is kept to a minimum through,

f 4

2 monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat i 2

detectors are strategically placed throughout rod testing area.. Where moderation control {

is in place, high expansion foam, dry chemical or CO are required to be' used to combat a ;

f fire. '

2 l

l All flammable and combustible liquids of greater than one pint in volume used in the l

l process are stored in fire rated containers.

j-l j

15.1.10.2.4 Environmental Safety 1

The concrete floors are sealed to be liquid tight and contain no floor drains. Room 189 is j 4

serviced by a "once through" HVAC system that is continuously monitored for radioactive j i

contamination. The exhaust systems for Room 189 are double HEPA filtered and have ;

j I

deluge systems to protect the final filters from fire.

l l

I 15.1.10.3 Rod Storane t

f

. The rod storage process consists of three storage racks, each of which holds multiple i

trays of loaded fuel rods. The storage rack in the southwest comer of Room 100 can hold i

thirty trays in an array that is six storage locations wide by five high. The storage rack in the southwest comer of Room 182 can hold sixty trays in an array that is twenty storage locations wide by three high. The storage rack in the north end of Room 193 can hold 196 l l

trays in an array that is twenty-two storage locations wide by nine high, with the exception I

?

inat two storage locations near the lower eastem comer of the rack have been replaced l

}

with a single line of rollers used for moving trays through the rack.

j 15.1.10.3.1 9dicality Safety i

The rod storage process relies on both administrative and engineered geometry control

~

and moderation control. Specifically, each storage location limits the height of rods to no more than 3.6 inches and neither water nor extraneous plastics may be introduced into the

- rack.

AMENDMENT APPLCATON DATE:

PAGE No.:

f April 15,1997 15-34d l

g sec nomo w ses2>

a

J i

I I

Siemens Power Corporation - Nuclear Division EMF-2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 PART 11-SAFETY DEMONSTRATION REV.

j i

.{

e' All Racks 4

i The Room 193 storage rack, being the largest, defines the limiting array.

l l

Summary of Accident Conditions Slab height violation was considered. The slab limit is 3.6 inches, which is maintained by a

the use of rod trays, each of which is designed not exceed 3.6 inches in depth. If this slab i

limit is violated in every storage location in the large storage rack such that each location..

I contains a 4.2 inch slab, the storage rack is suberitical, with up to 2.5 volume percent i L

I

- water uniformly interspersed in the storage rack. A single slab of rods, fully flooded, must j

' exceed six inches in depth before k, becomes unacceptable. Full flooding is prevented i

by storing the rods in trays that are open on both ends so that, should water enter the i

storage rack, it will run out.

[

l Water intrusion via flooding was considered. A' massive amount of water introduced into I

. the room in which a rod storage cabinet is located could result in the storage rack being

[

j flooded, either fully or up to some uniform depth. The defenses against this are the fact -

that the trays limit the rod height to less than or equal to 3.6 inches and they are stored ;

)

l with sufficient vertical distance to neutronically isolate the slabs from one another under l

full flooding.

j i

i 4

Water intrusion via a pipe leak was considered. One mechanism for introducing water into - l the storage rack is to have a pipe leak above the storage rack. This is protected against in l two ways: by a spray shield that will block a leak from the piping from running into the rack and by the roof over the storage rack.

Water intrusion via a building roof leak was considered. This is protected against in the following ways: by ensuring that the top of the storage rack is covered and by using rod 4

trays that are open on both ends. Additiona!!y, calculations show that even if the top layer of rods is fully flooded or if each layer of rod storage trays is flooded to 0.95 inches deep, i

the storage rack is adequately suberitical.

]

l Water intrusion via firefighting spray was considered. It is credible that a fire of sufficient magnitude could occur in the vicinity of the storage rack such that the fire department I

would need to enter the area with large capacity fire hoses and that the water from these fire hoses could enter the storage rack. This circumstance is protected against in the

[

following ways: significant quantities of combustible materials are not stored in the vicinity.

of the storage rack and by the use of either noncombustible or self-extinguishing panels to cover each of the storage lccations in the rack. These defenses protect against conditions that could result in a cnticality, namely that uniform interspersed moderation exceeds 2.5 vol.% or that each storage location is flooded in excess of 0.95 inches.

I AMENOMENT APPLCAtlON DATE:

PAGE NO.:

April 15,1997 15-34e sPC-ND 3330 947 (R.1/07 92)

- ~

- - - - - l

Siemens Power Corporation - Nuclear Division sup.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 PART 11 -SAFETY DEMONSTRATION REV.

Intrusion of plastic or other extraneous moderators was considered. This condition is prevented by placing strict administrative controls on what may be placed into the storage racks and by performing routine inspections of the trays before they are placed into the storage racks.

15.1.10.3.2 Radiation Protection i

Rod storage is performed in a low surface contamination controlled area. This area is operated at a pressure slightly below atmospheric to preclude egress of airbome contamination. In the rod storage racks the pellets are sealed in zirconium cladding so do not generate airbome contamination.

l 15.1.10.3.3 Fire Protection I

i The UO building is rated as noncombustible. Fire loading is kept to a minimum through 2

monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat 2

detectors are strategically placed throughout rod storage area. Where moderation control is in place, high expansion foam, dry chemical or CO are required to be used to combat a 2

fire.

All flammable and combustible liquids of greater than one pint in volume used in the l process are stored in fire rated containers.

i l

15.1.10.3.4 Environmental Safety j

The concrete floors are sealed to be liquid tight and contain no floor drains. The rooms are serviced by "once through" HVAC systems that are continuously monitored for radioactive contamination. The exhaust systems are double HEPA filtered and have I deluge systems to protect the final filters from fire.

1 l

AMENDutNT APPLCATON DATE:

PAGE NO.:

April 15,1997 15-34 f SPC ND 3330.947 (R-14712)

't i

4 j

Sifm::ns Power Corporation - Nuclear Division EMF.2

' SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 4.

~

PART11-SAFETY DEMONSTRATION REV..l-I i

..16.1.10 Rod Fabrication j

15.1.10.1 Rod Loadinsi e

The rod loading process consists of three hoods in Room 182 in which the finished pellets are inserted into previously lower end welded zirconium cladding. Outgas trays, after leaving the pellet outgas system, enter one of the three hoods where _the pellets are

• 4

' removed from the trays, placed into a pellet trough, and pushed into a fuel rod. The major system components are' manual and automatic rod loading hoods and the rod handling i

system?

15.1.10.1.1. Criticality Safety The rod loading process relies. on both' administrative and engineered controls on geometry, on moderator control, and on the presence.of neutron absorbers (steel in the pellet outgas trays) for criticality safety. The manual and automatic rod loading equipment l

have been evaluated and are acceptable.

l. - Manual Rod Loadina Hoods I

i

~ Criticality safety in manual rod loading hoods is maintained by controlling the pellet outgas tray stacks to 10 trays high and in an end-to-end configuration, by limiting the depth of pellets on the floors of the hoods to 3.6 inches maximum, by using self-draining equipment (trays, etc.) or keeping significant quantities of water out of the hoods, and by the design of the outgas trays to ensure a minimum steel mass of 2.5 kg for neutron absorption.

Summarv of Accident Conditions The evaluation of the manual rod loading hoods considered a number of possible upset i

j conditions simultaneously. These included overstacking of all outgas tray stacks (17 trays F high - the maximum stack height that will fit through the hood entry portal) within the hoods, having a 3.6 inch deep layer of pellets covering the floors of the hoods, optimizing the amount of moderator throughout the hood, and having full water reflection on all sides of the hood. -.With these simultaneous upsets, the manual rod loading hoods are still 5 adequately subcritical, i.e. k, is less than 0.95.

• Automatic Rod Loadina Hoods i

The automatic rod loading hoods have a different design from manual hoods. Instead of a row of end-to end outgas trays, the automatic hoods have five sets of rollers set side-by-

=, side with a 4 %" spacing between tray stacks maintained by the pallets. These five sets of f rollers are moved as a group from side-to-side which allows each of the roller sets to be loaded with a stack of outgas trays.

• AMENOW6NT APPLCATCN DATE:

PAGE No;

[

April 15,1997 15-34 SPC.ND7330 947 (R407 921

l

)

Siemens Power Corporation - Nuclear Division eu g.2 '

SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM 1227, NRC DOCKET NO. 70-1257 t

PART ll-SAFETY DEMONSTRATION

!REv.

l Criticality safety in the automatic rod loading hoods is maintained by controlling the pellet outgas tray stacks to 10 trays high, a maximum of 5 stacks in side-to-side configuration, by limiting the depth of pellets on the floors of the hoods to one inch maximum, by using l l

self-draining equipment (trays, etc.) or keeping significant quantities of water out of the :

hoods, and by the design of the outgas trays to ensure a minimum steel mass of 2.5 kg for neutron absorption.

Summary of Accident Conditions The evaluation of the automatic rod loading hoods considered a number of possible upset conditions simultaneously. These included overstacking of all outgas tray stacks (15 trays i

high - the maximum tray stack height that will fit through the hood entry portal) within the rod loading hood, having a full (one inch deep) catchpan of pellets on the hood floor, optimizing the amount of moderator throughout the hood, and having full water reflection on all sides of the hood. With these simultaneous upsets, the automatic rod loading process is still adequately suberitical, i.e. k,is less than 0.95.

Rod Handlina Rods are handled in the rod loading area in two different ways. The first is during the process of loading pellets into the rods and the second is after loading is complete. During loading, the rods are cycled through a sloped multi-tiered set of planes. After loading is complete, the rods are placed on a single-tier plane where the upper end caps are welded in place and are eventually transported to the rod testing process.

Criticality safety in the multi-tiered rod hcndling equipment depends upon controlling the total number of rods (to 150 maximum) and the depth of the rods per layer (one rod deep).

After loading, the rods are limited to a single tier maximum slab thickness of 3.6 inches which is 85% of a minimum critical slab thickness. Also the rod handling equipment is free draining.

I l Summary of Accident Conditions l The evaluation of the multilevel rod handling process considered combinations of the

- upset conditions of double batching the allowed number of rods and doubling the number l of reds per level. With these upsets and full flooding, the process has a maximum k, of 0.85, which is suberitical by a large margin. In the single level handling system, even though the slab thickness limit is 3.6 inches, the rods are handled ac a single rod layer of rods and the handling equipment will not allow more than one rod deep, i

i I

I augsowEst apptcarON DATE:

PAGE NO.:

l April 15,1997 15-34 a SPC-NO 3330 947 (R407 92) t

t Siernens Power Corporation - Nuclear Division EM F-2

' SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 i

i PART ll-SAFETY DEMONSTRATIC N

, REV.

l l 15.1.10.1.2 Radiation Protection l

l i

Rod loading is performed in a low surface contamination controlled area. This area is f I

operated at a pressure slightly below atmospheric to preclude egress of airbome :

contamination.

Sintered, ground and washed pellets do not pose problems with

~

generating airborne contamination.

15.1.10.1.3 Fire Protection I

The UO building is rated as noncombustible. Fire loading is kept to a minimum through 2

monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat 2

detectors are strategically placed throughout rod loading area. Where moderation control is in place, high expansion foam, dry chemical or CO are required to be used to combat a 2

fire.

All flammable and combustible liquids of greater than one pint in volume used in the

, process are stored in fire rated containers.

15.1.10.1.4 Environmental Safety J

The concrete floors are sealed to be liquid tight and contain no floor drains. Room 182 is serviced by a "once through" HVAC system that is continuously monitored for radioactive contamination. The exhaust systems for Room 182 are double HEPA filtered and have deluge systems to protect the final filters from fire.

15.1.10.2 Rod Testina The rod testing equipment is located in Room 189 of the UO Building. The following 2

pieces of equipment are included:

1)

The horizontal leak check station which checks for any intemal leakage l

from the rod which would indicate a possible incomplete weld or cladding l

pin hole; 2)

The AFRAS station which checks enrichment uniformity and pellet and l

plenum length measurements-i 3)

The X-ray station which checks for any abnormality within the we.'d and plenum areas; and i

4)

Associated equipment such as transfer carts, transfer vehicles and conveyors used to move groups of rods.

I

AWENOWENT APP CATION DATE

PAGE NO

L April 15,1997 l

15-34 b sPC-ND 3330 947 (R407 92)

Siemens Power Corporation - Nuclear Division sup.2' SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 i

PART ll-SAFETY DEMONSTRATION asv.

l 15.1.10.2.1 Criticality Safety The rod testing process relies on geometry control; specifically, that slab thickness not j

exceed 3.6 inches. It is further required that all equipment be free-draining to prevent water from accumulating in the interstitial spaces between the fuel rods and that no extraneous plastic be stored or used around or between the fuel rods.

All Eauipment

. The rods which are contained in process trays are transferred to and from the testing equipment via transfer carts. Each of the carts can transfer two process trays, which are i

approximately 15 inches on horizontal center. The infeed to the horizontal leak check station consists of a three tiered conveyor with the middle section at the same elevation as the leak checker. Each of these levels (approximately 15 inches vertical center) can hold two trays end-to-end.

The leak check station holds a maximum of one tray for testing purposes. In line with the exit of the station is a two tray (side-by-side as described previously) transfer cart for

transfer of the rods from the process trays to the AFRAS station. The AFRAS station

! holds a single level of rods side-by-side. The exit of the AFRAS transfers two levels of rods (approximately 10 inches on vertical center) into a single level which then roll on an inclined conveyor to the X-ray station infeed assembly. Approximately 150 rods maximum i can be contained on this inclined conveyor.

The X-ray handles 25 rods at a time in a single level. These rods, after being X-rayed, are loaded back onto the process trays and transferred to rod storage via a four-tiered conveyor system.

Because criticality safety is dependent upon maintaining a maximum slab depth of 3.6 4

inches, the design of the rod trays and conveyors ensures that this depth will not be exceeded. The design also ensures that the trays and conveyors are self-draining.

! Summary of Accident Conditions l Overstacking of rods was evaluated. Under optimum moderation and full water conditions k, for 0.30 inch diameter rods on a square pitch of 1.30 cm (most reactive array) for a 4.2 inch deep slab (minimum critical slab thickness) was 0.98. In bet, gravity will cause the rods to settle into a triangular pitch touching each other, which is less

! - reactive. The minimum critical slab depth for close packed rods is in excess of six inches.

I i

I i autuouoa amcarou oars:

- paceso:

April 15,1997 15-34c SPC-ND 3330 947 (R4 07 92) i

Sirm:nS Power Corporation - Nuclear Division eur2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 701257 l

PART 11 - SAFETY DEMONSTRATION REv. I i

i 15.1.10.2.2 Fadiaiian Protection l

Rod testirg is performed in a low surface centamination controlled area. This area is ;

j op?ratect at a pressure slightly below atmospheric to preclude egress of airbome contamination. At the rod testing station the pellets are sealed in zirconium cladding so do not generate airbome contamination.

15.1.10.2.3 Eire Protection The UO, building is rated as noncombustible. Fire loading is kept to a minimum through monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat 2

detectors are strategically p! aced throughout rod testing area. Where moderation control is in place, high expansion foam, dry chemical or CO are required to be used to combat a 2

fire.

All flammable and combustible liquids of greater than one pint in volume used in the process are stored in fire rated containers,

- 15.1.10.2.4 Environmental Safety I

The concrete floors are sealed to be liquid tight and contain no floor drains. Room 189 is serviced by a "once through" HVAC system that is continuously monitored for radioactive contamination. The exhaust systems for Room 189 are double HEPA filtered and have deluge systems to protect the final filters from fire.

15.1.10.3 Rod Storaae The rod storage process consists of three storage racks, each of which holds multiple trays of loaded fuel rods. The storage rack in the southwest corner of Room 100 can hold thirty trays in an array that is six storage locations wide by five high. The storage rack in the southwest comer of Room 182 can hold sixty trays in an array that is twenty storage locations wide by three high. The storage rack in the north end of Room 193 can hold 196 trays in an array that is twenty-two storage locations wide by nine high, with the exception

! that two storage locations near the lower eastem comer of the rack have been replaced with a single line of rollers used for moving trays through the rack.

i 15.1.10.3.1 Criticality Safety The rod storage process relies on both administrative and engineered geometry control and moderation control. Specifically, each storage location limits the height of rods to no more than 3.6 inches and neither water nor extraneous plastics may be introduced into the rack.

, AMENOWENT APPLCATON DATE:

PAGE No :

4 April 15,1997 l

15-34d SPC ND 3330 947 (A407 92)

Siemens Power Corporation - Nuclear Division EMF 2' SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 l

i t

l 1

PART ll-SAFETY DEMONSTRATION l REv. l l

l

• All Racks j

l The Room 193 storage rack, being the largest, defines the limiting array.

l Summary of Accident Conditions Slab height violation was considered. The slab limit is 3.6 inches, which is maintained by the use of rod trays, each of which is designed not exceed 3.6 inches in depth. If this slab limit is violated in every storage location in the large storage rack such that each location contains a 4.2 inch stab, the storage rack is subcritical, with up to 2.5 volume percent water uniformly interspersed in the storage rack. A single slab of rods, fully flooded, must exceed six inches in depth before k,, becomes unacceptable. Full flooding is prevented by storing the rods in trays that are open on both ends so that, should water enter the storage rack, it will run out.

Water intrusion via flooding was considered. A massive amount of water introduced into the room in which a rod storage cabinet is located could result in the storage rack being flooded, either fully or up to some uniform depth. The defenses against this are the fact l that the trays limit the rod height to less than or equal to 3.6 inches and they are stored with sufficient vertical distance to neutronically isolate the slabs from one another under full flooding.

Water intrusion via a pipe leak was considered. One mechanism for introducing water into the storage rack is to have a pipe leak above the storage rack. This is protected against in two ways: by a spray shield that will block a leak from the piping from running into the rack and by the roof over the storage rack.

Water intrusion via a building roof leak was considered. This is protected against in the following ways: by ensuring that the top of the storage rack is covered and by using rod trays that are open on both ends. Additionally, calculations show that even if the top layer of rods is fully flooded or if each layer of rod storage trays is flooded to 0.S5 inches deep, the storage rack is adequately suberitical.

Water intrusion via firefighting spray was considered. It is credible that a fire of sufficient

magnitude could occur in the vicinity of the storage rack such that the fire department l would need to enter the area with large capacity fire hoses and that the water from these

fire hoses could enter the storage rack. This circumstance is protected against in the following ways

significant quantities of combustible materials are not stored in the vicinity of the storage rack and by the use of either noncombustible or self-extinguishing panels to cover each of the r% rage locations in the rack. These defenses protect against conditiorm that could result in a critics l3f, aamely that uniform interspersed moderation exceeds 2.5 vol.% or that each storage location is flooded in excess of 0.95 inches.

l AVENDMENT APPLCATION DATE:

l PAGE NO.:

l April 15,1997 l

15-34e sPC-ND 3330 947 (R407 9h

i

, Siem':nS Powcr Corporation - Nuclear Division EMF-2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM 1227, NRC DOCKET NO. 70-1257 i

t PART ll-SAFETY DEMONSTRATION l REV. l l

1 Intrusion of plastic or other extraneous moderators was considered This condition is !

l prevented by placing strict administrative controls on what may be placed into the storage i

racks and by performing routine inspections of the trays before they are placed into the storage racks.

7 15.1.10.3.2 Radiation Protection Rod storage is performed in a low surface contamination controlled area. This area is operated at a pressure slightly below atmospheric to preclude egress of airborne

contamination. In the rod storage racks the pellets are sealed in zirconium cladding so do not generate airbome contamination.

15.1.10.3.3 Fire Protection The UO building is rated as noncombustible. Fire loading is kept to a minimum through 2

monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat 2

detectors are strategically placed throughout rod storage area. Where moderation control is in place, high expansion foam, dry chemical or CO are required to be used to combat a 2

l l fire.

All flammable and combustible liquids of greater than one pint in volume used in the

, process are stored in fire rated containers.

)

15.1.10.3.4 Environmental Safety The concrete floors are sealed to be liquid tight and contain no floor drains. The rooms are serviced by "once through" HVAC systems that are continuously monitored for radioactive contamination. The exhaust systems are double HEPA filtered and have deluge systems to protect the final filters from fire.

i l

l 1

J h AMENOMENT APPLICATION DATE:

April 15,1997 l PAGE NO:

15-34 f SPC ND 3330 947 (R a 07 92)

_ _. _ _.. _ _ _ _. ~..

f

\\

,k

.".1 Si:Im::ns Powar Corporation - Nuclear Division ew.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 j

i i

i PART ll-SAFETY DEMONSTRATION '

REV.' l 7>

_15.1.10 Redfabrication 15.1.10.1 Rod 1.oading

{

The rod loading process consists of three hoods in Room'182 in which the finished pellets l

are inserted into previously lower end welded zirconium cladding. Outgas trays, after leaving the pellet outgas system, enter one of the three hoods where the pellets are removed from the trays, placed into a pellet trough, and pushed into a fuel rod.' The major system components are manual and automatic rod loading hoods and the rod handling

}

system.

J..

15.1.10.1.1 Criticality Safety l

The. rod loading process relies on both administrative and engineered controls on geometry, on moderator control, and on the presence of neutron absorbers (steel in the j

pellet outgas trays) for criticality safety. The manual and automatic rod loading equipment have been evaluated and are acceptable.

be Manual Rod Loadina Hoods l Criticality safety in manual rod loading hoods is maintained by controlling tray stacks to 10 trays high and in an end-to-end configuration, by limiting the depth of l pellets on the floors of the hoods to 3.6 inches maximum, by using self-draining equipment

]

(trays, etc.) or keeping significant quantities of water out of the hoods, and by the design of the outgas trays to ensure a minimum steel mass of 2.5 kg for neutron absorption.

Summarv of Accident Conditions The evaluation of the manual rod loading hoods considered a number of possible upset

_ j. conditions simultaneously. These included everstacking of all outgas tray stacks (17 trays

- high - the maximum stack height that will fit through the hood entry portal) within the hoods, having a 3.6 inch deep layer of pellets covering the floors of the hoods, optimizing i

the amount of moderator throughout the hood, and having full water reflection on all sides l

of the hood. With these simultaneous upsets, the manual rod loading hoods are still adequately suberitical, i.e. k, is less than 0.95.

1

-4 Automatic Rod Loadina Hoods 1

l The automatic rod loading hoods have a different design from manual hoods. Instead of a

+-

i row of end-to end outgas trays, the automatic hoods have five sets of rollers set side-by-side with a 4 %" spacing between tray stacks maintained by the pallets. These five sets of

! rollers are moved as a group from side-to-side which allows each of the roller sets to be F

l loaded with a stack of outgas trays.

1-

)

- l ausNowENT appucatcN DAtt:

PAGs NO.'

l4 April 15,1997 15-34 SPC ND.3330 947 (R 107 92; i

c,

(

l Siemens Power Corporation - Nuclear Division EuF-2 SPECIAL NUCLEAR MATERIAL LICENSE NO, SNM 1227, NRC DOCKET NO. 701257 PART 11 - SAFETY DEMONSTRATION lREv.

l I

Criticality safety in the automatic rod loading hoods is maintained by controlling the pellet outgas tray stacks to 10 trays high, a maximum of 5 stacks in side-to-side configuration, by limiting the depth of pellets on the floors of the hoods to one inch maximum, by using t self-draining equipment (trays, etc.) or keeping significant quantities of water out of the hoods, and by the design of the outgas trays to ensure a minimum steel mass of 2.5 kg for neutron absorption.

i Summary of Accident Conditions l The evaluation of the adtomatic rod loading hoods considered a number of possible upset conditions simultaneously. These included overstacking of all outgas tray stacks (15 trays high - the maximum tray stack height that will fit through the hood entry portal) within the rod loading hood, having a full (one inch deep) catchpan of pellets on the hood floor, optimizing the amount of moderator throughout the hood, and having full water reflection on all sides of the hood. With these simultaneous upsets, the automatic rod loading process is still adeauately subcritical, i.e. k, is less than 0.95.

Rod Handlina I

i 1

Rods are handled in the rod loading area in two different ways. The first is during the process ofloading pellets into the rods and the second is after loading is complete. During loading, the rods are cycled through a sloped multi-tiered set of planes. After loading is complete, the rods are placed on a single-tier plane where the upper end caps are welded in place and are eventually transported to the rod testing process.

Criticality safety in the multi-tiered rod handling equipment depends upon controlling the total number of rods (to 150 maximum) and the depth of the rods per layer (one rod deep).

After loading, the rod are limited to a single tier maximum slab thickness of 3.6 inches which is 85% of a minimum critical slab thickness. Also the rod handling equipment is free

, draining.

Summary of Accident Conditions The evaluation of the multilevel rod handling process considered combinations of the upset conditions of double batching the allowed number of rods and doubling the number of rods per level. With these upsets and full flooding, the process has a maximum k, of 0.85, which is suberitical by a large margin. In the single level handling system, even though the slab thickness limit is 3.6 inchu, we rods are handled as a single rod layer of rods and the handling equipment will not allow more than one rod deep.

I j AWENOMENT AP%CATONDATE:

PAGE NOJ I

April 15,1997 15-34 a SPC-ND 3330 947 (R-107 92)

l,.-

S. i mens Pow::r Corporation - Nuclear Division Ew.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 -

I i

PART ll-SAFETY DEMONSTRATION f REV. j I

l l

15.1.10.1.2 Radiation Protection Rod loading is performed in a low surface contamination controlled area. This area is l j

operated at a pressure slightly below atmospheric to preclude egress of airbome contamination.

Sintered, ground and washed pellets do not pose problems with generating airbome contamination.

15.1.10.1.3 Fire Protection The UO, building is rated as noncombustible. Fire loading is kept to a minimum through monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat 2

detectors are strategically placed throughout rod loading area. i!here moderation cor; trol is in place, high expansion foam, dry chemical or CO are require i to be used to combat a 2

fire.

All flammable and combustible liquids of greater than one pint in volume used in the process are stored in fire rated containers.

15.1.10.1.4 Environmental Safety The concrete floors are sealed to be liquid tight and contain no floor drains. Room 182 is serviced by a "once through" HVAC system that is continuously monitored for radioactive contamination. The exhaust systems for Room 182 are double HEPA filtered and have deluge systems to protect the final filters from fire.

15.1.10.2 Rod Testina The rod testing equipment is located in Room 189 of the UO Building. The following 2

pieces of equipment are included:

1)

The horizontal leak check station which checks for any intemal leakage from the rod which would indicate a possible incomplete weld or cladding pin hole; 2)

The AFRAS station which checks enrichment uniformity and pellet and plenum length measurements; 3)

The X-ray station which checks for any abnormality within the weld and plenum areas; and 4)

Associated equipment such as transfer carts, transfer vehicles and conveyors used to move groups of rods.

i

{ AuCNDMENT APPLCATION DATE; PAGE No.:

April 15,1997 15-34 b sPC-ND 3330 947 (R-1.0792)

L i

c.

Siemens Power Corporation - Nuclear Division EMF-5 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 i

PART11 SAFETY DEMONSTRATION

nev, I

L 15.1.10.2.1 Criticality Safety i

The rod testing process relies on geometry control; specifically, that slab thickness not exceed 3.6 inches. It is.further required that all equipment be free draining to prevent water from accumulating in the interstitial spaces between the fuel rods and that no -!

l extraneous plastic be stored or used around or between the fuel rods.

All Eauioment i

The rods which are contained in process trays are transferred to and from the testing

, equipment via transfer carts. Each of the carts can transfer two process trays, which are approximately 15 inct.c on horizontal center. The infeed to the horizontal leak check station consists of a three tie.*d conveyor with the middle section at the same elevation as

the leak checker. Each of then levels (approximately 15 inches vertical center) can hold i

two trays end-to-end.

I j The leak check station holds a maximum of one tray for testing purposes. In line with the exit of the station is a two tray (side-by-side as described previously) transfer cart for

' transfer of the rods from the process trays to the AFRAS station. The AFRAS station holds a single level of rods side-by-side. The exit of the AFRAS transfers two levels of rods (approximately 10 inches on vertical center) into a single level which then roll on an l - inclined ccnveyor to the X-ray station infeed assembly. Approximately 150 rods maximum

can be contained on this inclined conveyor.

The X-ray handles 25 rods at a time in a single level. These rods, after being X-rayed, are loaded back onto the process trays and transferred to rod storage via a four-tiered conveyor system.

Because criticality safety is dependent upon maintaining a maximum slab depth of 3.6 j inches, the design of the rod trays and conveyors ensures that this depth will not be exceeded The design also ensures that the trays and conveyors are self-draining.

Summarv of Accident Conditions Overstacking of rods was evaluated. Under optimum moderation and full water reflection conditions k, for 0.30 inch diameter rods on a square pitch of 1.30 cm (most reactive array) for a 4.2 inch deep slab (minimum critical slab thickness) was 0.98. In fact, gravity I

will cause the rods to settle into a triangular pitch touching each other, which is less

! reactive. The minimum critical slab depth for close packed rods is in excess of six inches.

i k

AtaENuedENT APPLCATON DATE:

PAGE NQ.:

April 15,1997 15-34c SPC ND 3330 947 (A447 92)

.l

,Si:m:nS Power Corporation - Nuclear Division EM F-2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 i

i PART 11 - SAFETY DEMONSTRATION

' REv. j i

i 15.1.10.2.2 Radiation Protection Rod testing is performed in a low surface contamination controlled area. This area is !

operated at a pressure slightly below atmospheric to preclude egress of airbome contamination. At the rod testing station the pellets are sealed in zirconium cladding so do not generate airbome contamination.

15.1.10.2.3 Fire Protection The UO, building is rated as noncombustible. Fire loading is kept to a minimum through monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat 2

detectors are strategically placed throughout rod testing area. Where moderation control is in place, high expansion foam, dry chemicd or CO are required to be used to combat a 2

fire.

All flammable and combustible liquids of greater than one pint in volume used in the process are stored in fire rated containers.

15.1.10.2.4 Environmental Safety l

The concrete floors are sealed to be liquid tight and contain no floor drains. Room 189 is serviced by a "once thmuch" HVAC system that is continuously monitoed for radioactive contamination. The exhaust systems for Room 189 are double HEPA filtered and have deluge systems to protect the final filters from fire.

15.1.10.3 Rod Storaae The rod storage process consists of three storage racks, each of which holds multiple trays of loaded fuel rods. The storage rack in the southwest corner of Room 100 can hold thirty trays in an array that is six storage locations wide by five high. The storage rack in the southwest comer of Room 182 can hold sixty trays in an array that is twenty storage locations wide by three high. The storage rack in the north end of Room 193 can hold 196 trays in an array that is twenty-two storage locations wide by nine high, with the exception that two storage locations near the lower eastern comer of the rack have been replaced with a single line of rollers used for moving trays through the rack.

15.1.10.3.1 Criticality Safety The rod storage process relies on both administrative and engineered geometry control and moderation control. Specifically, each storage location limits the height of rods to no more than 3.6 inches and neither water nor extraneous plastics may be introduced into the j

rack.

7 P AGE NO.:

AVENDMENT APPLCATION DATE:

April 15,1997 l

15-34d SPC-ND 3330 947 (A407 92:

• c.

Siemens Power Corporation - Nuclear Division EMF-2' SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 I

PART 11 - SAFETY DEMONSTRATION l REv. l t

i All Racks i

The Room 193 storage rack, being the largest, defines the limiting array.

Summary of Accident Conditions Slab height violation was considered. The slab limit is 3.6 inches, which is maintained by the use of rod trays, each of which is designed not exceed 3.6 inches in depth. If this slab limit is violated in every storage location in the large storage rack such that each location contains a 4.2 inch stab, the storage rack is subcritical, with up *n 2.5 volume percent

water uniformly interspersed in the storage rack. A single slab of rods, fully flooded, must exceed six inches in depth before k, becomes unacceptable. Full flooding is prevented by storir,g the rods in trays that are open on both ends so that, should water enter the storage rack, it will run out.

Water intrusion via flooding was considered. A massive amount of water introduced into the room in which a rod storage cabinet is located could result in the storage rack being flooded, either fully or up to some uniform depth. The defenses against this are the fact that the trays limit the rod height to less than or equal to 3.6 inches and they are stored with sufficient vertical distance to neutronically isolate the slabs from one another under full flooding.

j Water intrusion via a pipe leak was considered. One mechanism for introducing water into the storage rack is to have a pipe leak above the storage rack. This is protected against in two ways: by a spray shield that will block a leak from the piping from running into the rack and by the roof over the storage rack.

Water intrusion via a building roof leak was considered. This is protected against in the following ways: by ensuring that the top of the storage race is covered and by using rod l trays that are open on both ends. Additionally, calculations shew that even if the top layer

' of rods is fully flooded or if each layer of rod storage trays is flooded to 0.95 inches deep, the storage rack is adequately subcritical.

t j Water intrusion via firefighting spray was considered. It is credible that a fire of sufficient magnitude could occur in the vicinity of the storage rack such that the fire department i would need to enter the area with large capacity fire hoses and that the water from these fire hoses could enter the storage rack. This circumstance is protected against in the

' following ways: significant quantities of combustible materials are not stored in the vicinity of the storage rack and by the use of either noncombustible or self-extinguishing panels to cover each of the storage locations in the rack. These defenses protect against conditions that could result in a criticality, namely that uniform interspersed moderation exceeds 2.5 vol.% or that each stcrage location is flooded in excess of 0.95 inches.

I i

ENOMENT APPLICATON DATE:

i PAGE NO.:

AM l

April 15,1997 l

15-34e sPC-ND 3330 947 tRa 07 9h

]

4 4

SiemenS Power Corporation - Nuclear Division-sus.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 j

4 PART 11 - SAFETY DEMONSTRATION

! REV. {

I Intrusion of plastic or other extraneous moderators was considered. This condition is l

prevented by placing strict administrative controls on what may be placed into the storage }

l J

racks and by performing routine inspections of the trays before they are placed into the l storage racks.

i 15.1.10.3.2 Radiation Protection Rod storage is performed in a low surface contamination controlled area. This area is operated at a pressure slightly below atmospheric to preclude egress of airbome

{

contamination. In the rod storage racks the pellets are sealed in zirconium cladding so do not generate airborne contamination.

i i

l 15.1.10.3.3 Fire Protection I

[ The UO building is rated as noncombustible. Fire loading is kept to a minimum through 2

monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat 2

i detectors are strategically placed throughout rod storage area. Where moderation control is in place, high expansion foam, dry chemical or CO, are required to be used to combat a fire.

All flammable and combustible liquids of greater 'han one pint in volume used in the l

process are stored in fire rated containers.

4

~

j 15.1.10.3.4 Environmental Safetv l

The concrete floors are sealed to be liquid tight and contain no floor drains. The rooms i

' are serviced by "once through" HVAC systems that are continuously monitored for radioactive contamination. The exhaust systems are double HEPA filtered and have deluge systems to protect the final filters from fire.

i i

,i 4

i i

I i

1 i

j AuswoM(NT A%CATON DATE:

PAGE NO :

April 15,1997 15-34 f SPC-ND 3330 947 (Ra;07 92) l

S.-

i j,1 Siimens Power Corporation - Nuclear Divisiori eup.2 -

N

' SPECIAL' NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257

~

1 I

i PART 11 -SAFETY DEMONSTRATION REv.!

I i

15.1.10 Rod Fabrication i

f 15.1.10.1 Rod Loadina The rod loading process consists of three hoods in Room 182 in which the finished pellets I j

are inserted into previously lower end welded zirconium cladding. Outgas trays, after leaving the pellet outgas system, enter one of the three hoods where the pellets are i

removed from the trays, placed into a pellet trough, and pushed into a fuel rod. The major.

l system components are manual and automatic rod loading hoods and the rod handling ~

. system.

15.1.10.1.1 Criticality Safety e

The rod loading-process relies on both administrative and engineered controls on geometry, on moderator control, and on the presence of neutron absorbers (steel in the pellet outgas trays) for criticality safety.' The manual and automatic rod loading equipment

)

! have been evaluated and are acceptable.

!e Manual Rod Loadina Hoods

~ Criticality safety in manual rod loading hoods is maintained by controlling the pellet outgas tray stacks to 10 trays high and in an end-to-end configuration, by limiting the depth of pellets on the floors of the hoods to 3.6 inches maximum, by using self-draining equipment (trays, etc.) or keeping significant quantities of water out of the hoods, and by the design of

)

' the outgas trays to ensure a minimum steel mass of 2.5 kg for neutron absorption.

)

Summarv of Accident Conditions e

The evaluation of the manual rod loading hoods considered a number' of possible upset t'

conditions simultaneously. These included overstacking of all outgas tray stacks (17 trays high - the maximum stack height that will fit through the hood entry portal) within the t

j i hoods, having a 3.6 inch deep layer of pellets covering the floors of the hoods, optimizing I

the amount of moderator throughout the hood, and having full water reflection on all sides I of the hood. With these simultaneous upsets, the manual rod loading hoods are still adequately suberitical, i.e. k,is less than 0.95.

• Automatic Rod Loadina Hoods j

. The automatic rod loading hoods have a different design from manual hoods. Instead of a row of end-to-end outgas trays, the automatic hoods have five sets of rollers set side-by.

side with a 4 %" spacing between tray stacks maintained by the pallets. These five sets of rollers are moved as a group from side-to-side which allows each of the roller sets to be i ' loaded with a stack of outgas trays.

AutNOWENT APPLCATONDATE

i PAGE NO; ji

' April 15,1997 l-15-34 SPC.ND 3330 947 (R407 921 t

n v-

SiemenS Power Corporation - Nuclear Division sus.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 701257 l

PART 11-SAFETY DEMONSTRATION

{ REv. f i

Criticality safety in the automatic rod loading hoods is maintained by controlling the pellet l

outgas tray stacks to 10 trays high, a maximum of 5 stacks in side-to-side configuration, by limiting the depth of pellets on the floors of the hoods to one inch maximum, by using i

I self-draining equipment (trays, etc.) or keeping significant quantities of water out of the hoods, and by the design of the outgas trays to ensure a minimum steel mass of 2.5 kg for neutron absorption.

Summarv of Accident Conditions l The evaluation of the automatic rod loading hoods considered a number of possible upset conditions simultaneously. These included overstacking of all outgas tray stacks (15 trays high - the maximum tray stack height that will fit through the hood entry portal) within the rod loading hood, having a full (one inch deep) catchpan of pellets on the hood floor, optimizing the amount of moderator throughout the hood, and having full water reflection on all sides of the hood. With these simultaneous upsets, the automatic rod loading process is still adequately suberitical, i.e. k, is less than 0.95.

Rod Handlina Rods are handled in the rod loading area in two different ways. The first is during the process of loading pellets into the rods and the second is after loading is complete. During loading, the rods are cycled through a sloped multi-tiered set of planes. After loading is complete, the rods are placed on a single-tier plane where the upper end caps are welded in place and are eventually transported to the rod testing process.

Criticality safety in the multi-tiered rod handling equipment depends upon controlling the total number of rods (to 150 maximum) and the depth of the rods per layer (one rod deep).

After loading, the rods are limited to a single tier maximum slab thickness of 3.6 inches which is 85% of a minimum critical slab thickness. Also the rod handling equipment is free draining.

l Summary of Accident Conditions l The evaluation of the multilevel rod handling process considered combinations of the upset conditions of double batching the allowed number of rods and doubling the number of rods per level. With these upsets and full flooding, the process has a maximum k, of 0.85, which is subcritical by a large margin. In the single level handling system, even though the slab thickness limit is 3.6 inches, the rods are handled as a single rod layer of rods and the handling equipment will not allow more than one rod deep.

! AutNDMENT APPLCATON DATE:

PAGE No.

April 15,1997 l

15-34 a i

SPC-ND 3330 947 (R-107 92)

,w' Siemens Power Corporation - Nuclear Division EMF 2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 s

PART 11 - SAFETY DEMONSTRATION

!REv.

j 15.1.10.1.2 Radiation Protection j

Rod loading is performed in a low surface contamination controlled area. This area is !

j operated at a pressure slightly below atmospheric to preclude egress of airbome contamination.

Sintered, ground and washed pellets - do not pose problems with generating airborne contamination.

15.1.10.1.3 Fire Protection The UO building is rated as noncombustible. Fire loading is kept to a minimum through 2

monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat 2

detectors are strategically placed throughout rod loading area. Where moderation control is in place, high expansion foam,' dry chemical or CO are required to be used to combat a 2

fire.

All flammable and combustible liquids of greater than one pint in volume used in the process are stored in fire rated containers.

15.1.10.1.4 gnvironmental Safety The concrete floors are sealed to be liquid tight and contain no floor drains. Room 182 is serviced by a "once through" HVAC system that is continuously monitored for radioactive contamination. The exhaust systems for Room 182 are double HEPA filtered and have deluge systems to protect the final filters from fire.

15.1.10.2 Rod Testina The rod testing equipment is located in Room 189 of the UO Building. The following 2

pieces of equipment are included:

1)

The horizontal leak check station which checks for any intemal leakage from the rod which would indicate a possible incomplete weld or cladding pin hole; I

2)

The AFRAS station which checks enrichment uniformity and pellet and plenum length measurements;

. 3)

The X-ray station which checks for any abnormality within the weld and plenum areas; and 4)

Associated equipment such as transfer carts, transfer vehicles and conveyors used to move groups of rods.

+

5 AMENOMENT APPLCATON DAtt:

l PAGE NOJ April 15,1997 l

15-34 b sPC ND 3330 947 (R40792)

Siemens Power Corporation - Nuclear Division eur.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 i

i PART ll-SAFETY DEMONSTRATION I

asv.

15.1.10.2.1 Criticality Safety The rod testing process relies on geometry control; specifically, that slab thickness not l

l exceed 3.6 inches. It is further required that all equipment be free <fraining to prevent.

water from accumulating in the interstitial spaces between the fuel rods and that no extraneous plastic be stored or used around or between the fuel rods.

All Eauipment The rods which are contained in process trays are transferred to and from the testing equipment via transfer carts. Each of the carts can transfer two process trays, which are approximately 15 inches on horizontal center. The infeed to the horizontal leak check station consists of a three tiered conveyor with the middle section at the same elevation as the leak checker. Each of these levels (approximately 15 inches vertical center) can hold two trays end-to-end.

The leak check station holds a maximum of one tray for testing purposes. In line with the exit of the station is a two tray (side-by-side as described previously) transfer cart for transfer of the rods from the process trays to the AFRAS station. The AFRAS station l holds a single level of rods side-by-side. The exit of the AFRAS transfers two levels of

' rods (approximately 10 inches on vertical center) into a single level which then roll on an inclined conveyor to the X-ray station infeed assembly. Approximately 150 rods maximum can be contained on this inclined conveyor.

The X-ray handles 25 rods at a time in a single level. These rods, after being X-rayed, are loaded back onto the process trays and transferred to rod storage via a four-tiered conveyor system.

Because criticality safety is dependent upon maintaining a maximum slab depth of 3.6 inches, the design of the rod trays and conveyors ensures that this depth will not be exceeded. The design also ensures that the trays and conveyors are self-draining.

l. Summarv of Accident Conditions l Overstacking of rods was evaluated. Under optimum moderation and full water re l conditions k,, for 0.30 inch diameter rods on a square pitch of 1.30 cm (most reactive

array) for a 4.2 inch deep slab (minimum critical slab thickness) was 0.98. In fact, gravity j

will cause the rods to settle into a triangular pitch touching each other, which is less reactive. The minimum critical slab depth for close packed rods is in excess of six inches.

l

)

I

! AMENDWENT APPUCATON DATE:

PAGE NO_:

l April 15,1997 15-34c

^

SPC-ND 3330 947 (R 107 92)

SiimenS Power Corporation - Nuclear Division EM F.2

' SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM 1227, NRC DOCKET NO. 70-1257 I

i i

PART 11 - SAFETY DEMONSTRATION

! REv. j i

i l

l 15.1.10.2.2 Radiation Protection Rod testing is performed in a low surface contamination controlled area. This area is l j

operated at a pressure slightly below atmospheric to preclude egress of airbome contamination. At the rod testmg station the pellets are sealed in zirconium cladding so do not generate airbome contamination.

15.1.10.2.3 Fire Protection The UO, building is rated as noncombustible. Fire loading is kept to a minimum through monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat 2

detectors are strategically placed throughout rod testing area. Where moderation control is in place, high expansion foam, dry chemical or CO are required to be used to combat a 2

fire.

All flammable and combustible liquids of greater than one pint in volume used in the process are stored in fire rated containers.

15.1.10.2.4 Environmental Safety l

The concrete floors are sealed to be liquid tight and contain no floor drains. Room 189 is serviced by a "once through" HVAC system that is continuously monitored for radioactive contamination. The exhaust systems for Room 189 are double HEPA filtered and have deluge systems to protect the final filters from fire.

15.1.10.3 Rod Storaae The rod storage process consists of three storage racks, each of which holds multiple trays of loadeJ fuel rods. The storage rack in the southwest corner of Room 100 can hold thirty trays in an array that is six storage locations wide by five high. The storage rack in the southwest comer of Room 182 can hold sixty trays in an array that is twenty storage locations wide by three high. The storage rack in the north end of Room 193 can hold 196 trays in an array that is twenty-two storage locations wide by nine high, with the exception that two storage locations near the lower eastem comer of the rack have been replaced with a single line of rollers used for moving trays through the rack.

15.1.10.3.1 Criticality Safety The rod storage process relies on both administrative and engineered geometry control and moderation control. Specifically, each storage location limits the height of rods to no more than 3.6 inches and neither water nor extraneous plastics may be introduced into the rack.

AVENDMENT APPtCATON DATE:

PAGE NO.:

April 15,1997 l

15-34d

$PC ND 3330 947 (R407 92;

i

'c Siemens Power Corporation - Nuclear Division e u r.2 -

- SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 l

l PART11-SAFETY DEMONSTRATION REV. l

'. All Racks i

l

' The Room 193 storage rack, being the largest, defines the limiting array.

j i

Summary of Accident Conditions Slab height violation was considered. The slab limit is 3.6 inches, which is maintained by the use of rod trays, each of which is designed not exceed 3.6 inches in depth. If this slab i

limit is violated in every storage location in the large storage rack such that each location l

contains a 4.2 inch slab, the storage rack is subcritical, with up to 2.5 volume percent water uniformly interspersed in the storage rack. A single slab of rods, fully flooded, must

)

, exceed six inches in depth before k, becomes unacceptable. Full flooding is prevented by storing the rods in trays that are open on both ends so that, should water enter the storage rack, it will run out.

i Water intrusion via flooding was considered. A massive amount of water introduced into i

the room in which a rod storage cabinet is located could result in the storage rack being l

l flooded, either ful!y or up to some uniform depth. The defenses against this are the fact

{ that the trays limit the rod height to less than or equal to 3.6 inches and they are stored with sufficient vertical distance to neutronically isolate the slabs from one another under full flooding.

4 i Water intrusion via a pipe leak was considered. One mechanism for introducing water into 1

the storage rack is to have a pipe leak above the storage rack. This is protected against in l

' two ways: by a spray shield that will block a leak from the piping from running into the rack and by the roof over the storage rack.

Water intrusion via a building roof leak was considered. This is protected against in the following ways: by ensuring that the top of the storage rack is covered and by using rod trays that are open on both ends. Additionally, calculations show that even if the top layer of rods is fully flooded or if each layer of rod storage trays is flooded to 0.95 inches deep, the storage rack is adequately suberitical.

Water intrusion via firefighting spray was considered. It is credible that a fire of sufficient a

magnitude could occur in the vicinity of the storage rack such that the fire department would need to enter the area with large capacity fire hoses and that the water from these f ' fire hoses could enter the storage rack.

This circumstance is protected against in the following ways: significant quantities of combustible materials are not stored in the vicinity of the storage rack and by the use of either noncombustible or self. extinguishing panels to cover each of the storage locations in the rack. These defenses protect against conditions that could result in a criticality, namely that unifomi interspersed moderation exceeds 2.5 vol.% or that each storage location is flooded in excess of 0.95 inches.

{

q AMENOWENT AM't. CATION DATE:

} PAGE NQ.:

4 2

l April 15,1997 15-34e i

SPc-ND 3330 947 (R-1-07'92)

-w w...-.. - -.

,-,... <. ~ -

i

,e -

, Siemens Power Corporation - Nuclear Division sup.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 i

PART ll-SAFETY DEMONSTRATION i REV. l i

l Intrusion of plastic or other extraneous moderators was considered. This condition is 2

prevented by placing strict administrative controls on what may be placed into the storage racks and by performing routine inspections of the trays before they are placed into the i

i storage racks.

15.1.10.3.2 Radiation Protectlp_n -

Rod storage is performed in a low surface contamination controlled area. This area is i

operated at a pressure slightly below atmospheric to preclude egress of airbome contamination in the rod storage racks the pellets are sealed in zirconium cladding so do

not generate airbome contamination.

~

15.1.10.3.3 Fire Protection The UO building is rated as noncombustible. Fire loading is kept to a minimum through 2

monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat 2

detectors are strategically placed throughout rod storage area. Where moderation control is in place, high expansion foam, dry chemical or CO are required to be used to combat a 2

l fire.

All flammable and combustible liquids of greater than one pint in volume used in the j process are stored in fire rated containers.

' 15.1.10.3.4 Environmental Safety The concrete floors are sealed to be liquid tight and contain no floor drains. The rooms are serviced by "once through" HVAC systems that are continuously monitored for radioactive contamination. The exhaust systems are double HEPA filtered and have deluge systems to protect the final filters from fire.

4 1.

1 l

l l

i i

t

' j AWENOWENT APPLCATON DATE:

' PAGE NO.:

April 15,1997 15-34 f i

SPC-ND 3330 947 (R-107/92)

I l

4 4

s' Sbm::ns Power Corporation - Nuclear Division eur.2 l

l, SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 i

PART 11-SAFETY DEMONSTRATION

. REv. l 1

l 15.1.10 Rod Fabrication 15.1.10.1 Rod Loadina The rod loading process consists of three hoods in Room 182 in which the finished pellets are inserted into previously lower end welded zirconium cladding. Outgas trays, after leaving the pellet outgas system, enter one of the three hoods where the pellets are removed from the trays, placed into a pellet trough, and pushed into a fuel rod. The major system components are manual and automatic rod loading hoods and the rod handling system.

15.1.10.1.1 Criticality Safety r

The rod loading process relies on both administrative and engineered controls on geometry, on moderator control, and on the presence of neutron absorbers (steel in the pellet outgas trays) for criticality safety. The manual and automatic rod loading equipment have been evaluated and are acceptable.

Manual Rod Loadina Hoods I

Criticality safety in manual rod loading hoods is maintained by controlling the pellet outgas tray stacks to 10 trays high and in an end-to-end configuration, by limiting the depth of pellets on the floors of the hoods to 3.6 inches maximum, by using self-draining equipment (trays, etc.) or keeping significant quantities of water out of the hoods, and by the design of the outgas trays to ensure a minimum steel mass of 2.5 kg for neutron absorption.

Summary of Accident Conditions 1

The evaluation of the manual rod loading hoods considered a number of possible upset

]

conditions simultaneously. These included overstacking of all outgas tray stacks (17 trays i

l high - the maximum stack height that will fit through the hood entry portal) within the hoods, having a 3.6 inch deep layer of pellets covering the floors of the hoods, optimizing the amount of moderator throughout the hood, and having full water reflection on all sides l of the hood. With these simultaneous upsets, the manual rod loading hoods are still j

~ adequately suberitical, i.e. k,is less than 0.95.

]

i Automatic Rod Loadina Hoods The automatic rod loading hoods have a different design from manual hoods. Instead of a

)

row of end-to-end outgas trays, the automatic hoods have five sets of rollers set side-by-side with a 4 %" spacing between tray stacks maintained by the pallets. These five sets of rollers are moved as a group from side-to-side which allows each of the roller sets to be l loaded with a stack of outgas trays.

i l

e AMENDMENT APPLCATION DATE:

i PAGE Noa l

April 15,1997 l

15-34 SPC ND 3330 947 (R407 92)

Siemens Power Corporation - Nuclear Division ew.r SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 I

l PART 11 - SAFETY DEMONSTRATION REv.

Criticality safety in the automatic rod loading hoods is maintained by controlling the pellet outgas tray stacks to 10 trays high, a maximum of 5 stacks in side-to-side configuration, by limiting the depth of pellets on the floors of the hoods to one inch maximum, by using self-draining equipment (trays, etc.) or keeping significant quantities of water out of the l hoods, and by the design of the outgas trays to ensure a minimum steel mass of 2.5 kg for l neutron absorption.

Summary of Accident Conditions The evaluation of the automatic rod loading hoods considered a number of possible upset

conditions simultaneously. These included overstacking of all outgas tray stacks (15 trays high - the maximum tray stack height that will fit through the hood entry portal) within the rod loading hood, having a full (one inch deep) catchpan of pellets on the hood floor, optimizing the amount of moderator throughout the hood, and having full water reflection on all sides of the hood. With these simultaneous upsets, the automatic rod loading process is still adequately suberitical, i.e. k,, is less than 0.95.

Rod Handlina Rods are handled in the rod loading area in two different ways. The first is during the process of loading pellets into the rods and the second is after loading is complete. During loading, the rods are cycled through a sloped multi-tiered set of planes. After loading is complete, the rods are placed on a single-tier plane where the upper end caps are welded in p! ace and are eventually transported to the rod testing process.

Criticality safety in the multi-tiered rod handling equipment depends upon controlling the total number of rods (to 150 maximum) and the depth of the rods per layer (one rod deep).

After loading, the rods are limited to a single tier maximum slab thickness of 3.6 inches which is 85% of a minii..um critical slab thickness. Also the rod handling equipment is free draining.

! Summarv of Accident Conditions The evaluation of the multilevel rod handling process considered combinations of the upset conditions of double batching the allowed number of rods and doubling the number l of rods per level. With these upsets and full flooding, the process has a maximum k, of

' O.85, which is subcritical by a large margin. In the tingle level handling system, even though the slab thickness limit is 3.6 inches, the rods ara handled as a single rod layer of rods and the handling equipment will not allow more than one rod deep.

t l

- vo o u m a m car m oars:

j pact e I

April 15,1997 l

15-34 a

$PC-ND.3330 947 (R-107 92)

o.

Siemens Power Corporation'- Nuclear Division eur.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM 1227, NRC DOCKET NO. 70-1257

\\

i PART ll-SAFETY DEMONSTRATION REV. j 15.1.10.1.2 Radiation Protection I

Rod loading is performed in a low surface contamination controlled area. This area is j

operated at a pressure slightly below atmospheric to preclude egress of airbome contamination.

Sintered,. ground and washed pellets do not pose problems with generating airborne contamination.

15.1.10.1.3 Fire Protection The UO building is rated as noncombustible. Fire loading is kept to a minimum through 2

monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat 2

detectors are strategically placed throughout rod loading area. Where moderation control is in place, high expansion foam, dry chemical or CO are required to be used to combat a

(

2 fire.

' All flammable and combustible liquids of greater than one pint in volume used in the

, process are stored in fire rated containers.

15.1.10.1.4 Environmental Safety i

' The concrete floors are sealed to be liquid tight and contain no floor drains. Room 182 is serviced by a "once through" HVAC system that is continuously monitored for radioactive contamination. The exhaust systems for Room 182 are double HEPA filtered and have deluge systems to protect the final filters from fire.

15.1.10.2 ftod Testina The rod testing equipment is located in Room 189 of the UO Building. The following 2

pieces of equipment are included:

1)

The horizontal leak check station which checks for any internal leakage from the rod which would indicate a possible incomplete weld or cladding pin hole; 2)

The AFRAS station which checks enrichment uniformity and pellet and l

plenum length measurements; 3)

The X-ray station which checks for any abnormality within the weld and plenum areas; and 4)

Associated equipment such as transfer carts, transfer vehicles and conveyors used to move groups of rods.

AMENDWENT APPLCAtl0N DATE:

i PAGE NO.:

t" April 15,1997 l

15-34b SPC.ND 3333 947 (R407 92)

.+

SiernenS Power Corporation - Nuclear Division eur.2 '

SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 PART ll-SAFETY DEMONSTRATION nsv.

l 15.1.10.2.1 Criticality Safety

)

The rod testing process relies on geometry control; specifically, that slab thickness not l

exceed 3.6 inches, it is further required that all equipment be free-draining to prevent j

water from accumulating in the interstitial spaces between the fuel rods and that no extraneous plastic be stored or used around or between the fuel rods.

All Eautoment The rods which are contained in process trays are transferred to and from the testing equipment via transfer carts. Each of the carts can transfer two process trays, which are

'. approximately 15 inches on horizontal center. The infeed to the horizontal leak check station consists of a three tiered conveyor with the middle section at the same elevation as the leak checker. Each of these levels (approximately 15 inches vertical center) can hold two trays end-to-end.

The leak check station holds a maximum of one tray for testing purposes. In line with the exit of the station is a two tray (side-by-side as described previously) transfer cart for transfer of the rods from the process trays to the AFRAS station. The AFRAS station j

holds a single level of rods side-by-side. The exit of the AFRAS transfers two levels of rods (approximately 10 inches on vertical center) into a single level which then roll on an inclined conveyor to the X-ray station infeed assembly. Approximately 150 rods maximum j

i can be contained on this inclined conveyor.

The X-ray handles 25 rods at a time in a single level. These rods, after being X-rayed, are loaded back onto the process trays and transferred to rod storage via a four-tiered conveyor system.

Because criticality safety is dependent upon maintaining a maximum slab depth of 3.6 j inches, the design of the rod trays and conveyors ensures that this depth will not be exceeded. The design also ensures that the trays and conveyors are self-draining.

Summarv of Accident Conditions Overstacking of rods was evaluated. Under optimum moderation and full water reflection conditions k, for 0.30 inch diameter rods on a square pitch of 1.30 cm (most reactive array) for a 4.2 inch deep slab (minimum critical slab thickness) was 0.98. In fact, gravity will cause the rods to settle into a triangular pitch touching each other, which is less reactive. The minimum critical slab depth for close packed rods is in excess of six inches.

l AMENOWENT APPLCATON DATE:

PAGE NO.:

]-

April 15,1997 15-34c SPC ND 3330 947 ( A+0792)

Sigrn@nS Pow @r Corporation - Nuclear Division EMF 2

' SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 PART ll-SAFETY DEMONSTRATION

, r:Ev, !

I i

i 15.1.10.2.2 Radiation Protection Rod testing is performed in a low surface contamination controlled area. This area is i J

i operated at a pressure slightly below atmospheric to preclude egress of airbome contamination. At the rod testing station the pellets are sealed in zirconium cladding so do not generate airbome contamination.

15.1.10.2.3 Fire Protection The UO building is rated as noncombustible. Fire loading is kept to a minimum through 2

monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat 2

detectors are strategically placed throughout rod testing area. Where moderation control is in place, high expansion foam, dry chemical or CO are required to be used to combat a 2

fire.

All flammable and combustible liquids of greater than one pint in volume used in the process are stored in fire rated containers.

15.1.10.2.4 Environmental Safety The concrete floors are sealed to be liquid tight and contain no floor drains. Room 189 is serviced by a "once through" HVAC system that is continuously monitored for radioactive contamination. The exhaust systems for Room 189 are double HEPA filtered and have deluge systems to protect the final filters from fire.

15.1.10.3 Rod Storace The rod storage process consists of three storage racks, each of which holds multiple trays of loaded fuel rods. The storage rack in the southwest comer of Room 100 can hold thirty trays in an array that is six storage locations wide by five high. The storage rack in the southwest comer of Room 182 can hold sixty trays in an array that is twenty storage locations wide by three high. The storage rack in the north end of Room 193 can hold 196 l trays in an array that is twenty-two storage locations wide by nine high, with the exception j that two storage locations near the lower eastem comer of the rack have been replaced with a single line of rollers used for moving trays through the rack.

I 15.1.10.3.1 Criticality Safety The rod storage process relies on both administrative and engineered geometry control and moderation control. Specifically, each storage location limits the height of rods to no more than 3.6 inches and neither water nor extraneous plastics may be introduced into the rack.

t

AMENOMENT APPLCATON DATE

i PAGE NO.:

l April 15,1997 l

15-34d SPC ND 3330 947 (R-007 92J

)

Siernens Power Corporation - Nuclear Division sus.2 -

SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 j

i l

l

\\

PART 11 - SAFETY DEMONSTRATION l REv. l l

i

• All Racks The Room 193 storage rack, being the largest, defines the limiting array.

l l

i i

i Summary of Accident Conditions Slab height violation was considered. The slab limit is 3.6 inches, which is maintained by the use of rod trays, each of which is designed not exceed 3.6 inches in depth. If this slab limit is violated in every storage location in the large storage rack such that each location contains a 4.2 inch stab, the storage rack is suberitiev, with up to 2.5 volume percent

water uniformiy interspersed in the storage rack. A single slab of rods, fully flooded, must exceed six incnes in depth before k, becomes unacceptable. Full flooding is prevented by storing the rods in trays that are open on both ends so that, should water enter the storage rack, it will run out.

Water intrusion via flooding was considered. A massive amount of water introduced into the room in which a rod storage cabinet is located could result in the storage rack being flooded, either fully or up to some uniform depth. The defenses against this are the fact j that the trays limit the rod height to less than or equal to 3.6 inches and they are stored

with sufficient vertical distance to neutronically isolate the slabs from one another under full flooding.

i Water intrusion via a pipe leak was considered. One mechanism for introducing water into the storage rack is to have a pipe leak above the storage rack. This is protected against in 1

two ways: by a spray shield that will block a leak from the piping from running into the rack and by the roof over the storage rack.

Water intrusion via a building roof leak was considered. This is protected against in the following ways: by ensuring that the top of the storage rack is covered and by using rod i

trays that are open on both ends. Additionally, calculations show that even if the top layer

! of rods is fully flooded or if each layer of rod storage trays is flooded to 0.95 inches deep, the storage rack is adequately suberitical, j

Water intrusion via firefighting spray was considered. It is credible that a fire of sufficient magnitude could occur in the vicinity of the storage rack such that the fire department would need to enter the area with large capacity fire hoses and that the water from these fire hoses could enter the storage rack. This circumstance is protected against in the l following ways: significant quantities of combustible materials are not stored in the vicinity of the storage rack and by the use of either noncombustible or self-extinguishing panels to cover each of the storage locations in the rack. These defenses protect against conditions that could result in a criticality, namely that uniform interspersed moderation exceeds 2.5 vol.% or that each storage location is flooded in excess of 0.95 inches.

I e

i AMENOWENT APPLCATION DATE:

j PAGE NO.:

l April 15,1997 l

15-34e SPC ND 3330 947 (R 107 921

)

Siemens Pow @r Corporation - Nuclear Division ew.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 i

PART 11 -SAFETY DEMONSTRATION

' REV.

I I

intrusion of plastic or other extraneous moderators was considered. This conditio'n is !

l prevented by placing strict administrative controls on what may be placed into the storage racks and by performing routine inspections of the trays before they are placed into the i

storage racks.

15.1.10.3.2 Radiation Protection -

Rod storage is performed in a low surface contamination controlled area. This area is operated at a pressure slightly below atmospheric to preclude egress of airborne contamination. In the rod storage racks the pellets are sealed in zirconium cladding so do not generate airbome contamination.

15.1.10.3.3 Fire Protection The UO, building is rated as noncombustible. Fire loading is kept to a minimum through monthly inspections. Fire extinguishers (dry chemical or CO:) al arm pull boxes, and heat detectors are strategically placed throughout rod storage area. Where moderation control is in place, high expansion foam, dry chemical or CO are required to be used to combat a 2

fire.

I All flammable and combustible liquids of greater than one pint in volume used in the

, process are stored in fire rated containers.

l 15.1.10.3.4 Environmental Safety The concrete floors are sealed to be liquid tight and contain no floor drains. The rooms are serviced by "once through" HVAC systems that are continuously monitored for radioactive contamination. The exhaust systems are double HEPA filtered and have deluge systems to protect the final filters from fire.

i I

l l

6 i autetut amcum oats:

jpaceuo:

l April 15,1997 1

15-34 f i

SPC-ND 3330 947 (R-UO7 92) j v

b

'~

o" Siem:nS Powcr Corporation - Nuclear Division eur.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 i

I i

PART 11 -SAFETY DEMONSTRATION

REv. t i

I I

f 15.1.10 Rod Fabrication 15.1.1o.1 Rod Loadino l

The rod loading process consists of three hoods in Room 182 in which the finished pellets are inserted into previously lower end welded zirconium cladding. Outgas trays, after leaving the pellet outgas system, enter one of the three hoods where the pellets are removed from the trays, placed into a pellet trough, and pushed into a fuel rod. The major system components are manual and automatic rod loading hoods and the rod handling system.

15.1.10.1.1 Criticality Safety The rod loading process relies on both administrative and engineered controls on geometry, on moderator control, and on the presence of neutron absorbers (steel in the pellet outgas trays) for criticality safety. The manual and automatic rod loading equipment have been evaluated and are acceptable.

Manual Rod Loadina Hoods f

Criticality safety in manual rod loading hoods is maintained by controlling the pellet outgas tray stacks to 10 trays high and in an end-to-end configuration, by limiting the depth of pellets on the floors of the hoods to 3.6 inches maximum, by using self-draining equipment (trays, etc.) or keeping significant quantities of water out of the hoods, and by the design of the outgas trays to ensure a minimum steel mass of 2.5 kg for neutron absorption.

Summary of Accident Conditions The evaluation of the manual rod loading hoods considered a number of possible upset conditions simultaneously. These included overstacking of all outgas tray stacks (17 trays high - the maximum stack height that will fit through the hood entry portal) within the hoods, having a 3.6 inch deep layer of pellets covering the floors of the hoods, optimizing the amount of moderator throughout the hood, and having full water reflection on all sides i of the hood. With these simultaneous upsets, the manual rod loading hoods are still adequately suberitical, i.e. k, is less than 0.95.

I Automatic Rod Loadino Hoods e

The automatic rod loading hoods have a different design from manual hoods. Instead of a row of end-to-end outgas trays, the automatic hoods have five sets of rollers set side-by-side with a 4 %" spacing between tray stacks maintained by the pallets. These five sets of rollers are moved as a group from side-to-side which allows each of the roller sets to be loaded with a stack of outgas trays.

i AMENDMENT APPLCATION DATE-i PAGE N0.

April 15,1997 l

15-34 SPC ND 3330.947 (R-107 92J l

l i

,o Siemens Power Corporation - Nuclear Division sw.2 ~

SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 701257 l

l PART 11 -SAFETY DEMONSTRATION l REv. l t

I Criticality safety in the automatic rod loading hoods is maintained by controlling the pellet l

outgas tray stacks to 10 trays high, a maximum of 5 stacks in side-to-side configuration, by limiting the depth of pellets on the floors of the hoods to one inch maximum, by using i j

self-draining equipment (trays, etc.) or keeping significant quantities of water out of the ;

hoods, and by the design of the outgas trays to ensure a minimum steel mass of 2.5 kg for neutron absorption.

Summary of Accident Conditions The evaluation of the automatic rod loading hoods considered a number of possible upset conditions simultaneously. These included overstacking of all outgas tray stacks (15 trays high - the maximum tray stack height that will fit through the hood entry portal) within the rod loading hood, having a full (one inch deep) catchpan of pellets on the hood floor, optimizing the amount of moderator throughout the hood, and having full water reflection on all sides of the hood. With these simultaneous upsets, the automatic rod loading process is still adequately suberitical, i.e. k,is less than 0.95.

Rod Handlina j

Rods are handled in the rod loading area in two different ways. The first is during the process of loading pellets into the rods and the second is after loading is complete. During loading, the rods are cycled through a sloped multi-tiered set of planes. After loading is complete, the rods are placed on a single-tier plane where the upper end caps are welded in place and are eventually transported to the rod testing process.

Criticality safety in the multi-tiered rod handling equipment depends upon controlling the total number of rods (to 150 maximum) and the depth of the rods per layer (one rod deep).

After loading, the rods are limited to a single tier maximum slab thickness of 3.6 inches which is 85% of a minimum critical slab thickness. Also the rod handling equipment is free draining.

I Summary of Accident Conditions l

l The evaluation of the multilevel rod handling process considered combinations of the upset conditions of double batching the allowed number of rods and doubling the number l of rods per level. With these upsets and full flooding, the process has a maximum k, of 0.85, which is subcritical by a large margin. In the single level handling system, even though the slab thickness limit is 3.6 inches, the rods are handled as a single rod layer of rods and the handling equipment will not allow more than one rod deep.

t i

, AMENOMENT APPLCATION DATE:

PAGE NO.:

April 15,1997 l

15-34 a SPC4JO 3330 947 (R.107 9h

,o i

SiemenS Powcr Corporation - Nuclear Division eur.2

- SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 i

i PART ll-SAFETY DEMONSTRATION

! REV. f l

l 15.1.10.1.2 Radiation Protection f

Rod loading is performed in a low surface contamination controlled area. This ares is j

operated at a pressure slightly below atmospheric to preclude egress of airSome '

contamination.

Sintered, ground and washed pellets do not pose problems with generating airbome contamination.

15.1.10.1.3 Fire Protection The UO, building is rated as noncombustible. Fire loading is kept to a minimum through monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat 2

detectors are strategically placed throughout rod loading area. Where moderation control is in place, high expansion foam, dry chemical or CO, are required to be used to combat a fire.

All flammable and combustible liquids of greater than one pint in volume used in the process are stored in fire rated containers.

15.1.10.1.4 Environmental Safety i

The concrete floors are sealed to be liquid tight and contain no floor drains. Room 182 is serviced by a "once through" HVAC system that is continuously monitored for radioactive contamination. The exhaust systems for Room 182 are double HEPA filtered and have deluge systems to protect the final filters from fire.

15.1.10.2 Rod Testina The rod testing equipment is located in Room 189 of the UO Building. The following 2

pieces of equipment are included:

1)

The horizontal leak check station which checks for any intemal leakage l

from the rod which would indicate a possible incomplete weld or cladding pin hole; l

2)

The AFRAS station which checks enrichment uniformity and pellet and plenum length measurements; 1

3)

The X-ray station which checks for any abnormality within the weld and plenum areas; and 4)

Associated equipment such as transfer carts, transfer vehicles and conveyors used to move groups of rods.

i

AWENOMENT APPLCATON DATE

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April 15,1997 15-34 b SPC-ND 3330 947 (R-107 92)

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Siemens Power Corporation - Nuclear Division eup.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 i

PART 11-SAFETY DEMONSTRATION l asy.

I 15.1.10.2.1 Criticality Safety The rod testing process relies on geometry control; specifically, that slab thickness not l

exceed 3.6 inches. It is further required that all equipment be free-draining to prevent I

water from accumulathg in the interstitial spaces between the fuel rods and that no extraneous plastic be stored or used around or between the fuel rods.

All Eauioment e

The rods which are contained in process trays are transferred to and from the testing equipment via transfer ca ts. Each of the carts can transfer two process trays, which are i

approximately 15 inches on horizontal center. The infeed to the horizontal leak check station consists of a three tiered conveyor with the middle section at the same elevation as the leak checker. Each of these levels (approximately 15 inches vertical center) can hold two trays end-to-end.

The leak check station holds a maximum of one tray for testing purposes. In line with the exit of the station is a two tray (side-by-side as described previously) transfer cart for

~ transfer of the rods from the process trays to the AFRAS station. The AFRAS station holds a single level of rods side-by-side. The exit of the AFRAS transfers two levels of rods (approximately 10 inches on vertical center) into a single level which then roll on an inclined conveyor to the X-ray station infeed assembly. Approximately 150 rods maximum can be contained on this inclined ccoveyor.

i The X-ray handles 25 rods at a time in a singie level. These rods, after being X-rayed, are loaded back onto the process trays and transferred to rod storage via a four-tiered conveyor system.

Because criticality safety is dependent upon maintaining a maximum slab depth of 3.6 j inches, the design of the rod trays and conveyors ensures that this depth will not be exceeded. The design also ensures that the trays and conveyors are self-draining.

Summarv of Accident Conditions Overstacking of rods was evaluated. Under optimum moderation and full water reflection conditions k, for 0.30 inch diameter rods on a square pitch of 1.30 cm (most reactive

. array) for a 4.2 inch deep slab (minimum critical slab thickness) was 0.98. In fr.ct, gravity will cause the rods to settle into a triangular pitch touching each other., which is less

'. reactive. The minimum critical slab depth for close packed rods is in excess of six inches.

i l

{ AMENDMENT APPLCATION DATE:

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l April 15,1997 15-34 c sPC.ND 3330 947 (R407 92)

'o Sizm:ns Pow r Corporation - Nucitar Division EM F-2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM 1227, NRC DOCKET NO. 70-1257 PART ll-SAFETY DEMONSTRATION REV. i

?

1 I

15.1.10.2.2 Radiation Protection l

l-Rod testing is performed in a low surface contamination controlled area. This area is i j

operated -at a pressure slightly below atmospheric to preclude egress of airbome contamination. At the rod testing station the pellets are sealed in zirconium cladding so do not generate airbome contamination.

15.1.10.2.3 Fire Protection The UO buil ding is rated as noncombustible. Fire loading is kept to a minimum through 2

monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat 2

detectors are strategically placed throughout rod testing area. Where moderation control is in place, high expansion foam, dry chemical or CO are required to be used to combat a 2

fire.

All flammable and combustible liquids of greater than one pint in volume used in the process are stored in fire rated containers.

15.1.10.2.4 Environmental Safety 1

The concrete floors are sealed to be liquid tight and contain no floor drains. Room 189 is serviced by a once through" HVAC system that is continuously monitored for radioactive contamination. The exhaust systems for Room 189 are double HEPA filtered and have deluge systems to protect the final filters from fire.

15.1.10.3 Rod Storaae The rod storage process consists of three storage racks, each of which holds multiple trays of loaded fuel rods. The storage rack in the southwest comer of Room 100 can hold thirty trays in an array that is six storage locations wide by five high. The storage rack in the southwest comer of Room 182 can hold sixty trays in an array that is twenty storage

! locations wide by three high. The storage rack in the north end of Room 193 can hold 196 l trays in an array that is twenty-two storage locations wide by nine high, with the exception j that two storage locations near the lower eastem comer of the rack have been replaced

with a single line of rollers used for moving trays through the rack.

15.1.10.3.1 Criticality Safety

' The rod storage process relies on both administrative and engineered geometry control and moderation control. Specifically, each storage location limits the height of rods to no more than 3.6 inches and neither water nor extraneous plastics may be introduced into the rack.

AWENOWENT APPLCATON DATE

P AGE NO :

i April 15.1997 l

15-34d sPC ND 3330 947 (R40792) 4

o*

.p P

Siemens Power Corporation - Nuclear Division eur.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 i

l REv. l PART ll-SAFETY DEMONSTRATION t

• All Racks l

l The Room 193 storage rack, being the largest, defines the limiting array.

f j

l Summary of Accident Conditions Slab height vlotation was considered. The slab limit is 3.6 inches, which is maintained by the use of rod trays, each of which is designed not exceed 3.6 inches in depth. If this slab limit is violated in every storage location in the large storage rack such that each location contains a 4.2 inch slab, the storage rack is suberitical, with up to 2.5 volume percent

water uniformly interspersed in the storage rack. A single slab of rods, fully flooded, must exceed six inches in depth before k, becomes unacceptable. Full flooding is prevented by storing the rods in trays that are open on both ends so that, should water enter the storage rack, it will run out.

Water intrusion via flooding was considered. A massive amount of water introduced into the room in which a rod storage cabinet is located could result in the storage rack being flooded, either fully or up to some uniform depth. The defenses against this are the fact

! that the trays limit the rod height to less than or equal to 3.6 inches and they are stored I

with sufficient vertical distance to neutronically isolate the slabs from one another under full flooding.

l Water intrusion via a pipe leak was cone dered. One mechanism for introducing water into the storage rack is to have a pipe leak above the storage rack. This is protected against in two ways: by a spray shield that will block a leak from the piping from running into the rack and by the roof over the storage rack.

Water intrusion via a building roof leak was considered. This is protected against in the following ways: by ensuring that the top of the storage rack is covered and by using rod l trays that are open on both ends. Additionally, calculations show that even if the top layer of rods is fully flooded or if each layer of rod storage trays is flooded to 0.95 inches deep, the storage rack is adequately subentical.

Water intnJsion via firefighting spray was considered. It is credible that a fire of sufficient magnitude could occur in the vicinity of the storage rack such that the fire department would need to enter the area with large capacity fire hoses and that the water from these fire hoses could enter the storage rack. This circumstance is protected against in the

> following ways: significant quantities of combustible materials are not stored in the vicinity of the storage rack and by the use of either noncombustible or self-extinguishing panels to cover each of the storage locations in the rack. These defenses protect against conditions that could result in a criticality, namely that uniform interspersed moderation exceeds 2.5 vol.% or that each storage location is flooded in excess of 0.95 inches.

i AMENOMENT APPLCATON DATE:

1 PAGE No.:

l April 15,1997 l

15-34e SPC-ND 3330 947 (Aa 07 92)

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Siemens Power Corporation - Nuclear Division sup.2 SPECIAL NUCLEAR MATERIAL LICENSE NO. SNM-1227, NRC DOCKET NO. 70-1257 PART 11 - SAFETY DEMONSTRATION

' REV.

i I

Intrusion of plastic or other extraneous moderators was considered. This condition is i

prevented by placing strict administrative controls on what may be placed into the storage i racks and by performing routine inspections of the trays before they are placed into the l storage racks.

l 15.1.10.3.2 Radiation Protection Rod storage is performed in a low surface contamination controlled area. This area is operated at a pressure slightly below atmospheric to preclude egress of airborne contamination. In the rod storage racks the pellets are sealed in zirconium cladding so do not generate airborne contamination.

15.1.10.3.3 Fire Protection The UO building is rated as noncombustible. Fire loading is kept to a minimum through 2

monthly inspections. Fire extinguishers (dry chemical or CO ) alarm pull boxes, and heat 2

detectors are strategically placed throughout rod storage area. Where moderation control is in place, high expansion foam, dry chemical or CO are required to be used to combat a 2

. fire.

i All flammable and combustible liquids of greater than one pint in volume used in the process are stored in fire rated containers.

15.1.10.3.4 Environmental Safety The concrete floors are sealed to be liquid tight and contain no floor drains. The rooms

' are serviced by *once through" HVAC systems that are continuously monitored for radioactive contamination. The exhaust systems are double HEPA filtered and have deluge systems to protect the final filters from fire.

I i

i l

i 1 AWENouf NT APPLCATON DATE:

PAGE NO

April 15,1997 l

15-34 f SPC ND 3330 947 ( Aa 07 92) i