ML19225A216

or State Triga Reactor Operating Procedures, Rept 11,fuel Handling Procedures

ML19225A216
Person / Time
Site:	Oregon State University
Issue date:	07/11/1979
From:	Oregon State University, CORVALLIS, OR
To:
Shared Package
ML19225A209	List: ML19225A208 ML19225A216
References
PROC-790711, NUDOCS 7907180570
Download: ML19225A216 (17)

Text

.

OSTROP 11.0 Fust EteastiT HAf1DLING Paccsouass TABLE OF CO!.T .TS Score: 1 A. General Information 1

1. Fuel Moderator Elerants  ;

2. Instrurented Fuel Elements 1

3. Graph:.te Du==y Elements

4. Fual Handling Tool 2

5. Fuel Element Inspection Tool 3

6. Fuel Ele =ent Transfer Cask 4 B. General Considerations and Hazards 6 C. Procedures 7 11.1 Fuel Element Handling Procedures 11.2 Fuel Element Inspection Tool Cperaticn 9

a. Precperational Procedures 9

b. Zeroing the Dial Indicator 9

c. Adjust =ent of Bellcws Travel 9

d. Inspecting a Fuel Element 10 11.3 Operation of a '"ypical Fuel Element Transfer Cask 12

a. Famoving Fuel fram the Reactor Tank 12

b. Discharging Fuel into the Storage Pits 12

c. Removing Fuel from the Storage Pits 13

d. Paplacing Fuel into the Reactor Tank 1-D. Authorizatica 13 346 07d 790nso 57 0 /o

t IV.ll.1 0 STROP 11.0 FUEL ELEMENT HANDLING PROCEDURES Scs >J . The OSTRO? 11.0 series proceduras are given to direct the operator in the approved methods for handling fuel elements.

A. GENEPAL I'.*F0F?.ATIC'I The foll; wing information describes the equipment that will probably be used to handle and inspect fuel elements.

1. Fuel-Moderator Elements The fuel-moderator elements contain a circonium-hydride moderator, hemogeneously combined with partially enriched uranium fuel. As indicated in Fig. 1. 17 (Vol . 1) the active section of this fuel moderator element is 15 in. in length and 1.43 in. in diameter and 235 contains approximately 8.5 wt-% uraniu=, enriched to 20% in U (70% in TLIP fuel) . The hydrogen-to-circonium atom ratio of the fuel-moderator material is about 1.7 to 1. To facilitate hy-driding, a 0.25-in.-diameter hole is drilled through the center of the active fuel section; a circenium rod is inserted in this hole after hydriding is complete. Graphite slugs, approximately 3.5 in.

in length and 1.4 in. in diameter, act as top and bottom reflectors.

The active fuel section and top and botton graphite slugs, are contained in a 0.02-in.-thick stainless steel can. The stainless steel can is welded to the top and bottom end fittings. The top end fitting is grooved and specially shaped to fit and 1cck into the fuel handling tool. The tcp end fitting also incorporates a triangular spacer block that positions the top of the element in the top grid and yet provides passages for cooling water flow through the grid. The bottom end fitting fits into the countersunk holes of the boqtom grid plate and supports the entire weight of the element. The approximate everall reight of the element is 7.5 lbs; the U -- content ranges from about 35 to 40 grams (% 125 233 grams in FLIP fuel). Se rial numbers on the top end fixture er spacer block are used to identify fuel elements. When properly installed in the core, the top cf the triangular spacer block is about level with the top of the top grid plate.

Instrurented Fuel Elenents Some fuel-moderator elements are ecuipped with three chrcmet=1" a:

thermocoaples embedded in die fuel. As shown in Fig. 1.15 (Vol, 1) ,

the sensing tips of the fuel element Sne rmoccuple are located halfway to the 'certical centerline at the center of the fuel section and 1 in. above and below the horirontal center.

346 08l

P/.ll.2 Each thermocouple consists of two 0.005-in.-diameter wires e= bedded in MgG insulation and contained in a 0.040-in.-diameter stainless steel sheath. The sheathed thermocouples pass through z. soft solaer seal which is contained in a 3/4-in.-disneter leadeut tub e welded to the upper end fixture. This tube proj ecto about 3 in.

above the upper end of the element and is extended by two lengths of tubing connected by unions to provide a water-tight conduit extending above the water surf ace in the reactor pool. Just above the soft solder seal, a transition is made to heavier thermocouple leadaut wires and to a ground wire attached to the sheath. The transition joint is sealed in a potting sleeve. The color-coded leadout wires (chromel-yellow is positive, alumel-red is negative) at are 20 gauge with a parallel resistance of 59 ohms per 100 ft.

75 F. Care must be exercised when handling or connecting the wires.

In other respects, the instrumented fuel-moderator element is iden-tical to the standard element.

3. Grachite Du==y Elements Graphite du=my elements occupy the grid positions not filled by fuel-coderator elements and other core components. The graphite dummy elements are canned in alm.inum and have aluminua end fixtures and spacer blocks. These elecer ts are of the same dimensions as the fuel-toderator elements, bu t are filled entirely with graphite.

Each graphite du==y element we tghts 2.8 lbs. and is anodized af ter assembly. The spacer blocks have a blue anodized finish to take the graphite dur=y elements easily distinguishable from fuel-moderator elements. When properly installed in the core, the top of the triangular spacer block is doout level with the top of the top grid plate.

4. Fuel-Handling Tool The fuel-handling tool, shown in Figure 1.66 (Vol.1) is used for handling the fuel-moderator and graphite du==y elements. It consists of a stainless steel grapple techanism, a stainless steel weight, a flexible stainless steel control cable with a handle that can be locked in any position, and a reinforced rubber hose that extends between the handle and the weight for transmitting the weight of a fuel elecent to the handle .

Four stai.nless steel balls protruding through the inside wall of a cylinder in the grapple techanism slip into a groove on the alum-inwn top end-fixture of an element that has been pushed into the cylinder. The cylinder slides with reference to the rest of the grapple mechanism and holds the balls so that they cannot slip out of the groove in the end fixture.

To take apart the grapple assembly for inspection or repair, first remove the small Allen-head locking screw in the side, then, helding the weight in one hand and grapple mechanism in the other, rotate one relative to the other so as to unscrew the icwcr part of the grapple.

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IV.ll.3 The proper adjustment of the fuel-nandling tool is important to assure that fuel elecents are not inadvertantly released during handling. Refer to the general notes on the fuel-handling tcci drawing for th_ procedures to follow to adjust the tool properly.

5. Zuel-Element Insoection Tool De scription The fuel-element inspection tool (see Fig. 1.6 7, Vol .1) is used to accurately iccpect a pulsing fuel element for longitudinal grew h and for bowing in excess of 0.062 in.

The upper support plate of the tool is counted with two 1/2-in.

bolts en the aluminum channel at the top of the reactor tank and extends dcwnward 12 ft. into the tank , permitting the inspection cf an irradiated fuel element and providing approximately 9 ft. ot shielding water over the element. All parts of the tool to be in contact with water are either alu=inun or stainless steel. The aluminum support-tube structure has a hole at the bottom end and another at the top to allow shield water to fill the interior of the pipe.

The bowing of a fuel element is detected by a carefully machined cylinder (a go/no-go gauge) attached to the bottom of the tcol.

If a fuel element will slide completely into the cylinder, its bow, if any, is less than 0.062 in. If the element passes through its cylinder, it will come to rest on the plunger of the spring-loaded bellcws assembly. The length of the fuel eleneat is measured by pushing downward (approximately 10 lb. of force is recuired) en the indexing rod until the indexing plug shoulders on the inde xing plate. This places the upper surface of the fuel-element triangular spacer at an indexed pcsition common to all fuel elenents measured.

pushing the fuel element dcwnward to this position forces the icwer plunger dcwnward an amount that varies with the leng of the fuel element being measured. A bellows attached to the plunger extends and displaces a portion of the water cc:. fined in the bellows hcusing. This displaced water pushes through the transmission line to the upper bellows assembly, forcing an identical bellows to contract. The contraction of the upper bellows causes the upper plunger to rise the same distance that the Icwer plunger <as puched downward. The movement of the upper plunger is measured with a dial indicator.

A standard element is furnished with the inspection tool; it is a solid piece of aluminum with the sane dimensions and the sare top and bot :om end fixtures as those er a regular fuel eierent. This standari! element must be inserted co calibrate the teol. The amount s f bellcws displacement c aused by the standard eierent is used to zero the dial indicator. E ve r*j fuel eierent in the ccra can ther be measured and its length :crpared with that of the M> 6 0p3 _

I7.11.4 s t a:. N rd . Careful records should be .<ept of each fuel element, grid location, and length, compared with the standard elecent.

Instrumented (thermoccuple) fuel elements can alco be inspected with this tool. (3j using a different indexing plate, a longer go/no-go gauge, and a cc==y fueled follower standard, a fueled follcwer control rod can also be inspected.)

Fuel elements that do not pass the elcngaticn and bowing tests should not be used for further pulsing operations. Currently , the United States :;uclear Regulatory Commission requires that elements which have bewing in excess of 0.062 in. and longitudinal growth in excess of 0.10 in. be removed from the core prior to continued pulsing.

6. Fuel-Element Transfer Cask Cescription of a Typical Fuel-Element Transfer Cask A typical fuel-element transfer cask (see Fig. 11.1) is designed to permit the safe transfer of irradiated fuel elements and o*.her radioactive material from the reactor tank to the fuel storage pits or a hot cell facility; it consists of a stee? casing filled with lead, and weighs approximately 5700 lbs. The cask is 45 in.

long by 20 in. outside diameter eith a 2-in.-diameter cavity extending the full length of the cask to hold a single fuel element.

Eyebolts are provided cn the top for the attachment of lifting cables.

The bottom of the cask contains a 5-in .-high , steel-sheathed lead plug that slide's hericontally across the end of the fuel element cavity to provide shielding. This plug can be locked in place with a spring loaded locking bolt at-sched to the cask. The top of the cask is ecuipped with a removable lead shield plug which is siced to pass through the central fuel elenent cavity. The plug can be locked in position at the top of the cask with the rotating locking keys attached to the cask.

In order to minimice the oossible rustinc of the cask and de-position of corrosion procucts in the water, the cask shoul . be immersed in the reactor tar.k only during actual fuel transfer operatic-s and recored as soon as possible. The paint on the cask should carefully .' ain ta'.ne d .

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1. Irradiated fuel elements are the strongest source of radiation within th e reactor. When the reactor is at powe r , a f ue l e ie re nt is a scurce of intense gamma and neutron radiation. After shuticwn, fissica prcduct decay in the fuel continues to =ake the element a streng beta-gamma source, although the beta radiation is, for the most part, absorbed in tha fuel cladding. Calculations indicate dr.a t if the reactor is cperated at 250 kW for several hours, the equilibrium activity associated with one of these elements is appro:cimately 2.5 x 10" curies at the time of shutdown. Th e cal-culated dose rate in air from a single fuel element after prolcnged operatica at 250 kW and at a distance of 6 ft. is approximately 2.5 x 103 rcentgens per hour at the time of shutdown. Cf course, this dose rate initially decays rapidly, but whenever fuel elements are to be "' d'ed, careful surve 's with reliable health-ph/ sics instruments should first be made.

2. In operating a TRIGA, it may be necessary to transfer fuel f rca the reactor tank to storage. Because of the radiation level associated with irradiated fuel-toderacor elements, elements are ncr= ally kept under water for chielding. If an element must be removed f ron the reactor tank, it should be placed in a shielded transfer cask to reduce radiation levels to tolerable limits.

3. In addition to the external radiation hacards present during fuel transfer Operations , loose oxides and other irradiated particulates on the surf ace of the fuel element cladding constitute a potential contamination hazard. This tactile contaminacion can be trans-ferred to handling equiprent and eventually to personnel, if in-proper' handling techniques are erployed. Care must be taken to contain any liquid that drips from the fuel elerant or the transfer cask; persennel should wear protective clothing; and a continuous air monitor should be used to detect any particulate or gaseous activity that may become airborne. Equipment used in tne transfer of a ruptured fuel element must be carefully handled to avoid spreading contamination.

4. Unless great care is exercised, cross :cntanination of the reactor facility can occur during fuel element transfer between the reactor facility and a hot cell. If the fuel transfer cask is ta.<en into a cell, it will undoubtedly become contaminated. Its return to the reactor f acility in a contaminated condition nay spread contanination to otherwise clean areas, b

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C. PROCEOU?I3 11.1 Fuel Element Handling Procedurer

a. The fuel element is engaged to the flexible handling too. b; lowering the tool directly ever the top of the element end-fixture; the weight of the tool causes engagement. (The fuel eierent end-fixture is thus locked to the fuel-handling tool.)

b. To release the fuel element it is necessary to first anlock the handle at the operator end of the tool. This is done by rotating the handle aJoout 70 degrees counterclockwise ind pulling it out approximately 3 inches. This a:tica =cces an internal cylinder relative to the rest of the grapple techanism, and the tool ball bearings are pushed out of the element end-fixture groove, thus releasing the ele =ent.

c. Since the handling tool will slide in and lock automatica11;. ,

the handle should never be in the unlocked position except comentarily when it is intended that an ele ent should be released.

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( ., ) .snen Inserting or removing ele =ents, be certain the handle is locked and that the teol is

=amirely attached to the eierent by gently shaking the tool.

(2)  ;. hen a fuel elenent is engaged in the grapple rech anism, the handle end of the tool should never be laid on the ficor or on the tank covers, where it could be actuated accidentally.

(3) i:ever force the handle into cr cut of a locking

_ position. If it does not rotate easily, push or pull the handle slightly, then try again.

Forcing the handle will da age the locki ng grooves of the handle.

(4) When a fuel element is engaged in the tool re ch anism, never coil the control cable in a circle of a diameter less than about 2 fee t .

A tight coil will pull the inner control cable and may release the elenent even though tne handle is locked.

346 087 _

~,.,.,.a A s (5) *Taen withdrawing (or inserting) fuel ele ents, be certain -he tool and clament are vertical over the grid plate hole before covement is made. S ide forces on the fuel element may cause .<i.nking or wri .kli .7 o .c.  %..

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. . .3 (6) Unen inserting fuel elements in the reactor core, be sure each fuel element is seated in its proper lower grid plate position. 'icen properly seated, the tcp of the tri-flute spacer, which is located on top of the fuel element, will be on a level horizontal plane and very sligntly below the level of the upper g._ _4 -a ,0, 1 , =_ . '. .' th a_ *-i "uluu=_ o. mV

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flute appears to be signi: cantly below the upper grid plate, the element will be angled into the wrong lower g rid .clate .cosition. Tne tri-flute position should be determined by using binoculars to locs 'hrough the water frca the top of the reactor tank.

(7) The tri-flute spacers en the 70T enriched FLI? fuel elements are distinctively different from those en the 2 0 ~s enriched standard TRIGA fuel clarents. See Ficire 1. This physical features na'<es it easy to identif;. the FLIP and stan ' #"el clerents in the core. At the time cach newlf loaded fuel element is cbserved for proper seating, verifs that the #uel element is of the tyre intanded to be inserted into that scecific core position. Furthernore, there are to be .o_ standard TRICA fuel eierents in any grid positica except in a specifically approved positica in the cuter ring of the core. If there are any c.uesticas, contact the reactor supervisor.

d. Instrumented fuel elenents do not require the use of the fuel handling tool. The element can be handled (carafully) using the 3/* in. tubing that houses the ther .acouple leadcut wires.

e. Fuel follower control rods do not require the use of the fuel handling teol. The fuel follower control rods c2. be handled (carefully) by using the long entansicns that connect the control rod drives to the control rods.

f. The constant air monitor (CXI) will hee en at 111 times during K!Y fuel elenent handling. (This includes storage pic fuel cl>r.'nu 5. .' . . A ' .i . . ~y . )

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346 089 -

IV.11.9 11.2 Puel Element Insrection Tocl Operation

a. Preope rational Procedure Eacn day the inscection tool is to be used, the following steps cust be taken before neasuring the length of the fuel elenents:

(1) P.e rcve the fill plug and the 'ent plug at the upper end of the inspection tool and check the water level.

(2) If the water level is icw, add denineralized water to the hvdraulic system throu,5 the fill cpening. Continue to add water until all air is purged f rom the system through the vent hole.

(3) Replace the fill and vent plugs.

(4) Adjust the be:el en the dial indicator to give a cero reading.

( 5) As the tarperature of the water in the hydraulic cystem approaches that of the reactor tank wate r, it will expand or contract causing the pointer of the dial indicator to ecve. When the pointer of the dial indicator stops moving, remove the fill plug. Add water, if necessary, and repl2ce the plug.

b. Zeroing the Dial Indicator Each day the inspection tool is to be used, or af ter measuring 20 fuel elements, re-cero the dial indicator as follows:

(1) With the fuel-handling tool, lower the standard dummy into the go/no-go gauge so that its bottom end rests on the plunger of the lower bellows assembly.

(2) Rencve the fuel-handline tool.

c. Adiustrenc of Bellows Travel (1) At scre cite it may be necessary to change or readjuct th e distance the standard element tri-spacer protrudes above the indexing plate. If adjustrent is required, urjooit and remove the indexing plate (and go/no-go gauge attached tc it) . Loosen the 10-32 set screw in the nut which surrounds the lower plunger.

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The lower plunger is aelded to the lower eru of the bellcws. Be ver'j careful not to twist th e plunger and damage the belicws:

(2) Hold the plunger in a fixed position and rotate the nut.

Tightening the nut centracts the bellcws and moves the

.clunger upward. The nut should not be tigntened rcre than is actually necessary since this action reduces the range of bellcws travel. Se sure to retighten the 10-32 set screw when adjustrents have been comple ted.

( 3) Using the indexing rod, place the indexing plug in one of the six l-in.-diareter holes in the incexing plate.

(4) Push down (approximately 10 lb. force is required) cn the indexing rod until the pointer of the dial indicator stops moving, indicating that the dummy is indexed.

(5) Adjust the dial-indicator berel to zero the pointer while holding the standard du==y in the index position.

(G) To ensure that the standard dummy is undistorted, repeat steps 3 and 4 twice, using other holes in the indexin- ,. clate, 120* apart. These dial-indicator readings should also be zero.

(7) Renove the indexing red and the standard dunny.

(8) 'dhen preparing the fuel ceasuring tool for measuring fueled follower control rods, the Mbove procedures are also used, except that a special indexing plate and longer go/no-go gauge replace the ones used for fuel elenents. The diareter of the longer go/no-go gauge is sized to reject a fueled follower element that has a bow in excess of 0.062 in. in 24 in. of length (the same as the standard element gauge)

Cabolt the fuel element indexing plate (and gauge connected to it) from the flange on the support tub e and bolt the fueled follower indexing plate and gauge to a like flange on the support tube about 22 in.

above. Use the special fueled follower standard dummy and follow the above procedures for cercing the dial indicator.

d. Inspectinc a Fuel Elerent Inspect the fuel element for excessive bow and dete-rrine its length by the follo. sing precedure:

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( 1) Insert the fuel element into the go/no-go by using the fuel-element handling .tcol. If the fuel eierent passes freely through the gauge, it is within allowable straightness tolerance; if not, the element has a bow in excess of 0.062-in.

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Cd'i v e i*w . 4 Never force or drop a fuel element Ehrough the go/no-go gauge. To do so may damage the gau;c, cause damage to the cladding of the element, or ja the element in the cylinder. To pass the bow test the element should pass through the go/no-go gauge while being icwered slowly through the cylinder.

(2) Af ter the straightness test, recove the fuel-handling tool and insert the indexing red in one of the indexing holes in the indexing plate adjacent to a corner of the fuel element triangular spa;er.

(3) Force the indexing rod down until the element is indexed. Record the dial indicator reading.

(4) Repeat steps 2 and 3 twice, using holes in th e indexing plate adjacent to the other two corners of the triangu_ar spacer.

(5) Average the three dial-indicator readings and add thi.

average algebraically to the length of the standard du=y; the result is the leng-h of the fuel ele ent inspected.

(6) Instrumented fuel elements are inspected in the same ranner, except that the fuel-handling tool is noi re quired . The element should be handled carefully, using 3/4-in. tubing that houses the the rmoccuple leadout wires.

(7) With the special indexing plate and go/no-go gauge for fueled follcwer control rods in place and the measuring tool properly calibrated, fueled follower control recs may clso be inspected using the above procedures. With the control extension shaf ting still attached to the control rod, the fuel element handling tool is not required. (With the extension shaf ting removed, however, there is a standard fuel element tip on the :cp of the control rod to which the handling tool will attach.)

I 7 . 1 1 . 12 11.3 Oceration of a Typical Puel Element Transfar Cask

a. Removinc a Fuel Element f rom tne Reactor Tank (1) Prepare the transfer cask for immersion in the reactor tank by wiping all surfaces with a damp cloth or sponge to remove dust and dirt. Remove dirt and grease frca lif ting cables and slings. Re move the shielding plags at the bottom and top of the cask.

(2) With a crane of adequate capacity, raise the transfer cask over the reactor tank so Unat the bottom of the cask is approximately 3 ft. above the surface of the water. While the cask is sept in this position, lower the fuel-handling tool through the cavity of the cask to the fuel elenent.

( 3) Guiding the flexible tool by hand, engage the fuel element, and remove it from the core (or storage rack) so it is suspenced vertically belcw the cask, being careful to keep it under sufficient water for adequate shielding.

(4) While ensuring that the element remains engaged, lower the cask until ics top is 4 f t. belcw the surface of the water.

(5) Sicwly -'.ise the flexible cable and fuel-handling tool until t, element is in the cask.

AAPl;r:C Avoid standing directly over the top of the cask.

There will be radiation streaming upward from the cavity of the cask, because the re is little shielding on the top of the fuel element; the fuel element is surrounded by lead only on the sides.

(6) Holding the handling-tool cables so as to keep the fuel element within the cask, slowly lift the cask just above the water so that the icwer shield plug can be inserted and locked in place. Lower the fuel element onto the shield plug, and remove the fuel-handling tool from the fuel element, keeping clear of the radiatica streaming f rom the top of the cask. Insert and locs the top shield plug in place.

b. Dischargina a Fuel Element into the Puel Storace Pit CAUTION A suitable storage area (storage pit) with adequate shielding must be provided for irradiated fuel 346 093 .

IV.11.13 elements renoved f 3 the reactor tank. If water is to be used as a shielding material in the storage pit, it should be changed from time to time, to assure its purity and icw conductivity.

(See CSU TRIGA Reactor Technical Specifications for fuel storage conditions.)

(1) Set the transfer cask on the ficor directly over the fuel storage pit, which should be filled with de-nineraliced water.

(2) Avoiding the radiation streaming from the top of the cask, unlock and remove the top shield plug, and attach the fuel-handling tool to the top of the fuel element.

(3) Withdraw the bottom shield plug caly partially (to raintain shielding) to alica the fuel elecent to pass through. The fuel handling tool now will hold the entire seight of the elenent. Lower the element to a position near the bottom of the pit.

(4) While ensuring dat the element remains near the botton of the pit, cc=pletely ramove the bottom shield plug (to be sure it does not fall out) and lift the cask about 3 ft. above the floor to permit visual observation, and install the element in a suitable receptacle at the botter of the pit.

(5) Disengage the fuel-handling tool frca the fuel element, and remove it from the cask.

c. Removing a Fuel Element frc= the Fuel Storace Pit (1) Re=ove the bottom and top shield plug. Insert the fuel handling tool into the transfer cask cavity.

(2) Raise the transfer cask about 3 ft. Maove the floor, directly over the storage pit, and lower the fuel-handling tool to the botton of the pit.

( 3) Guiding the cables by hand, engage th e f ue l e leme n t .

(4) Lower the cask to the floor directly over the storage pit.

(5) Partially insert the bottom shield plug for shielding, but alicw enough clearance f o r che fuel element to pass i ..o

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(6) S low ly lift the eierent into the cask. Lock the botton shield plug in place.

346 094

IV.11.14

,n.,......,n._...o Avoid standing directly over the top of the cask.

There vill be radiation streaming upward from the cavity of the cask, because there is little shielding on the top of the fuel element: the fuel element is surrounded by lead cnly on the sides.

(7) Rancve the fuel-handling tool frc= the fuel elecent, keeping clear of the radiation streaming from the top o f the ca sk . Insert and lock the top shield plug in place.

d. Replacin a Fuel Element in the Reactor Tank (1) Make available a position in the grid or storage rack th at is accessLble frc= directly above.

(2) Lower the transfer cask until it is just iaove the water surface.

( 3) Avoiding the radiation strea=ing from the top of ;he cask, unlock and remove the top shield-plug, and attach the fuel-handling tool to the top of the fuel element.

(4) Unlock and _ at;'re the lower shield plug, holding the weight of the elecent with the fuel-handling tool.

(5) Lower the trsnsfer cask until the top of the cask is approximately 4 ft. belcw the surf ace of the water.

(6) Lower the element to a position doout 2 ft. above the core or storage rack.

(7) With the element remaining in this position, raise the cask until it is about 3 ft. above the surtace of the water.

(S) Guiding the flexible tool by hand, lower the eierent to the proper core er storage rack position.

(9) Disergage the fuel-handling tool f rom the fuel element, and remove ic from the cask.

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IV.ll.15 D. Authorization Proper authorization =ust be obtained before an fuel elements are handled or any changes in core configuration are made. The Reactor Supervisor or the Reactor Operations Cc==ittee must authorize any such core change or fuel element handling.

1. Ite=s that may be authorized by the Reactor Supervisor:

a. Any =ovement of a single fuel element out of the core to accc==cdate an experi=ent, and the subsequent replace-cent of this fuel element into the core.

b. The per=anent addition of up to two fuel elements to the core to increase the excess reactivity.

c. Any =ovement of new or irradiated fuel elements not in the core.

d. The re= oval of fuel elements frc= the core for maintenance purpcses, provided that the reactor remains shutdown during the ti=e that the fuel elements are out of the core, and the subsequent replacement of these fuel ele =ents into the core, such that the core configuratica has remained intact.

2. Ite=s that =ust be authorized by the Reactor Cperations Cc==ittee: An'f fuel ele =ent novements except those listed in

1. a., b., and c., above must be authorized.by the Reactor Operations Cc=rittee. After such authorization has been chtained, the Reactor Supervisor will schedule and supervise the approved fuel move =ent.

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