FUEL

FUEL-1 Movement of Fuel

I. INTRODUCTION

A. PURPOSE

The instructions of this procedure are to control the movement of reactor fuel components within the reactor core grid structure and to or from storage locations.

B. DESCRIPTION

Reactivity changes occur as fuel is added to the reactor core or storage locations. To assure adequate safety margins for the proper performance of the control rod system, procedural controls define the requirements and limitations for fuel movement within the reactor core and storage areas. These rules include changing the arrangement of fuel components as well as fuel additions or deletions.

C. Schedule

Apply this procedure each time fuel is moved.

D. Contents

A. TRIGA Fuel Movement

B. Criticality and Inventory Control of Materials in Storage

C. TRIGA Fuel Reference Reactivity Values

E. Attachments

Fuel Movement Log

TRIGA Core Arrangement

Storage Well Arrangement

Pool Storage Rack Inventory

Fuel in Inventory Disqualified for Use

F. Equipment, Materials

Fuel Element Tool

Radiation Work Permit (RWP) - A RWP is required for this procedure only if irradiated fuel is to be moved outside of the reactor pool access area.

7. REFERENCES

   Criticality Calculations

   MAIN-5 Fuel Inspections and Measurements

   MAIN-5 Performance Records

   B159.xls (Fuel Data)

II. PROCEDURE

A. TRIGA Fuel Movement

1.0 See following P&I Procedure Change Insert Page

1.1 A senior reactor operator shall supervise all movements of fuel, including movements to or from the reactor core grid structure and movements between storage locations. At least one person should assist with the handling of the fuel elements.

2. Restrict all fuel element arrays except the reactor core to an array limit of less than 20 elements.

   1. Store fuel elements in the fuel storage wells or in the reactor pool. Use the 19 element hexagonal array racks (these may be stacked two deep per well) or the 6 or staggered 12 element linear array racks.

   2. Elements not in storage racks or shipment casks should be in groups of three or less.

3. Plan fuel movement activities so as to minimize the number of individual moves required to achieve the desired result.

4. Move elements between the reactor core, storage racks, shipment casks or other locations with special fuel handling tool.

5. Maintain access control or restrict use of fuel handling tool by lock if fuel movements are not in progress.

6. Test fuel handling tool on non-fuel element prior to use.

7. Approve by inspection and test any device other than the fuel handling tool prior to use for movement of fuel. Handle the instrument elements with the extension tubes. Handle control followers with the extension rods.

8. Handle fuel elements carefully. Care should be taken not to bump or scrape elements. Minimize the possibility and potential consequences of an accidental drop of an element.

9. The Pool Area radiation monitor shall be functional during fuel movement in or to and from the reactor pool.

10. Verify a gamma sensitive survey instrument (with audible or alarm functions) is present in the area where the fuel movement will occur. A Radiation Work Permit (RWP) is necessary for movement of irradiated fuel beyond the immediate vicinity of the reactor pool access area.

11. The air particulate monitor or substitute monitor should be functioning.

12. Record all fuel element movements in the Fuel Element Log.

13. Acknowledge by verbal response each change of fuel handling tool opened or closed status if two persons operate the tool.

14. Acknowledge by verbal response the exchange or transfer of the fuel handling tool to another person.

15. Operate and monitor the reactor console during the movement of fuel to or from the reactor core.

    1. Prevent movement of any control rod drive by removing the neutron source from the core.

    2. Place the console in Manual Mode. Verify no control rods will withdraw.

    3. A log of any event will be automatically recorded to the control system history file.

    4. Removal of a fuel followed control rod from the core for inspection requires a minimum shutdown margin greater than 0.2% Δk/k (2 rods out) (i.e., with the rod being removed out and the remaining highest worth rod up).

    5. Movement of an instrument element requires disconnect and reconnect of instrument connections with a functional test prior to reactor operation.

16. Verify excess reactivity and shutdown margin if fuel movement is to or from the reactor core. Check by measurement or calculate by conservative estimate.

17. Compare control rod critical positions before and after movement and recalibrate if a change occurs due to movement of the fuel in the core.

18. Upon completion of fuel movement the fuel handling tool shall be surveyed for contamination, bagged, and locked securely for storage in its designated location.

B. Criticality and Inventory Control of Materials in Storage

1. Storage and handling of large quantities of special nuclear materials (SNM), such as reactor fuel, carries the risk of accidental criticality if the materials are placed into a critical geometry or moderated with hydrogenous materials. Tracking of licensed SNM is required (10CFR74) and annually reported to the NRC via the Nuclear Materials Management and Safeguards System (NMMSS). The total quantity of SNM at the NETL shall not exceed a Category III (Low Strategic Significance) quantity of material as defined in 10CFR73.2 (<10kg unirradiated). The NETL Reactor Facility License, R- 129, requires all fuel elements to be stored in a geometrical array where the effective multiplication is less than 0.8 for all conditions of moderation. TRIGA elements stored in a 19 element rack and MCZPR elements stored in a linear array are sufficiently subcritical.

2. SNM, other than irradiated fuel and the subcritical assembly, in quantities greater than 1.0 gram should be stored in room 2.204B, the Auxiliary Equipment Room (AER), when not actually in use or prepared for shipment. The subcritical assembly should not be stored near other fuel in the AER, but should be stored in its 55 gal drum maintained within the confines of the reactor bay. Sealed neutron sources (e.g., PuBe) shall NEVER be stored within the AER. Neutron sources may be used within the AER for Criticality Alarm instrument checks as noted below.

3. A Criticality Accident alarm system is required by 10CFR70.24 for SNM not stored underwater when the total quantity of enriched U-235 exceeds 700 grams. Monitoring is not required for fuel stored in the storage pits if they are maintained underwater. The NETL Criticality Accident monitor is a Ludlum 375 gamma and neutron unit or equivalent meeting the requirements of 10CFR70.24. The digital monitor should be mounted outside the AER with the detectors located adjacent to the MCZPR fuel storage location. The detector system is calibrated annually and response checked quarterly using a neutron/gamma source. The audible alarm setpoint should be set between 5 and 20 mR/hr.

4. Routine entry into the AER requires the SRO issue the key. The SRO will verify the individual has been trained to properly enter and work within the AER prior to key issue.

5. Individuals entering the AER must note the readings of the Criticality Accident Monitor outside the AER and verify the digital meters are at typical background levels (expected to be less than 5.0 mR/hr and 5.0 mrem/hr) prior to entry. If necessary, movement of moderator (e.g., graphite, polyethylene, water) materials into or within the AER requires SRO supervision.

6. Fuel element (TRIGA or MCZPR) movement within the NETL requires SRO supervision. The SRO will ensure fuel elements are moved in limited quantities and maintained in a subcritical configuration during movement.

C. TRIGA Fuel Reference Reactivity Values

Core Location	TRIGA fuel vs. water
Ring A	4.00
Ring B	1.07
Ring C	0.85
Ring D	0.54
Ring E	0.36
Ring F	0.25
Ring G	0.19
3 elements (1D, 2E)	1.25
6 elements (6B)	6.42

FUEL-2 Movement of Experiments

I. PURPOSE

The purpose of this procedure is to control experiment facility or experiment movements that may cause reactivity changes to the reactor core.

II. DESCRIPTION

Setup or removal of reactor core experiment facilities and experiments can cause substantial changes in the core configuration reactivity. Knowledge of these reactivity changes, both magnitude and sign, and the measurement of these changes is necessary to approve any configuration for safe operation.

III. REFERENCE

Safety Analysis Report,

docket 50-602

Technical Specifications,

section 3.4 limitations on Experiments

IV. MATERIALS

Radiation Work Permits (RWP) - for work within the reactor pool access area, or for special experiments.

V. PROCEDURE

1. A licensed operator shall supervise all experiment facility or experiment movements in the reactor pool.

2. A careful examination of the reactivity consequences of any experiment or facility movement shall be reviewed.

3. Reactivity effects greater than $1.00 shall require supervision by a licensed senior operator; reactor startup checklist shall be performed and k-excess adjustments made as necessary.

4. Removal or replacement of experiment or facilities into or from the reactor core shall be recorded in the reactor logbook; a k-excess measurement shall be made at time of subsequent reactor criticality.

5. All experiments in the reactor tank shall be secured as required by reactivity constraints. Experiments or objects in the reactor pool that represent no reactivity effect shall be secured as necessary to prevent potential interference with reactor operation.

6. A beta-gamma survey shall be made of all objects or experiments removed from the pool; radiation tags and wipe tests should be used as necessary.

   1. Check the requirements of any extended or fixed RWP for work in the immediate area of the reactor pool access area.

   2. Special RWP’s may apply to specific experiments.

Reactivity Estimates ($)

Experiment/Item	Comparison	$
CTR	void vs. water	-0.50
dummy min.	graphite vs. water	+0.05
dummy max.	graphite vs. water	+0.20
thru tube	void vs. graphite	-0.45
piercing tube	void vs. graphite	-0.35
RSR	poison 40 places	-0.40
PNT-G1	poison	-0.16
PNT-A1	poison	-0.90

poison is a significant neutron absorbing material