SPENT FUEL RERACK ALARA PLAN

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					                    VC SUMMER
           SPENT FUEL RE-RACK ALARA PLAN
Purpose:

In an effort to maintain dose ALARA during the re-racking project, a spent fuel re-rack
dose reduction plan was developed. This plan encompasses various aspects of the re-rack
evolution from preparations to shipping of old racks.

Scope:

The spent fuel pool is being re-racked to increase storage locations with the new high-
density racks supplied by Holtec International. A total of 11 racks are being removed
from the pool. These racks will be replaced with 12 high-density racks.

Because of the high population of fuel assemblies in the pool, a new rack shall be
temporarily placed on a support platform in the Cask Pit and loaded with fuel in order to
reduce the number of assemblies in the pool during the re-racking operation.
Additionally, due to the limited range of travel of the overhead crane, a temporary crane
shall be provided to install and remove all racks in the spent fuel pool.

In order to support the new racks, the sparger piping along the south pool wall shall
require some segmentation of the vertical run of pipe. Additionally, some light bracket
supports may require some trimming to allow the fuel handling tool access to shadowed
cells.

Diving evolutions are planned for modifying the existing sparger piping. Additionally, a
diver may be utilized to assist in bearing pad removal or installation, rack leveling, and
rigging/placement as necessary.

Goal:

The goal of the Spent Fuel Re-rack ALARA plan is to have the re-racking performed in a
controlled manner such that no significant industry event occurs such as personnel
injuries or radiological incidences. The re-rack dose goal is set at 2.0 Rem or less. The
dose estimate for the job is ~2.0 Rem. This dose goal will be monitored on a daily basis
and will provide an indication of any unexpected trends in dose accumulated during this
evolution. If accumulated dose does not track as expected this will allow for early
evaluation of causes to be conducted. Table 1 shows a breakdown of estimated dose for
various activities during the re-rack. Figures 1 and 2 show the daily estimated dose for
the re-rack activities.




                                             1
Water Management:
The Spent Fuel Purification demineralizer has been verified to be adequate for the project
and a determination was made that the demineralizer will not be sluiced until needed or
after the re-rack project is completed. In the event the Spent Fuel Purification demin is
sluiced, it has been verified that the primary spent resin storage tank has enough available
volume to except the purification demineralizer. The Spent Fuel Purification demin will
be utilized to maintain water quality and to reduce radioactivity of the water.
Consideration has been given to securing the Spent Fuel Purification pumps while
removing the old racks to prevent spreading large amounts of activity throughout the
system.

Two Tri-Nuc filter units will be utilized during the Spent Fuel re-rack. The first unit (260
gpm) will be used to vacuum the floor and debris and normally utilizes 6-micron filters.
The second unit (600 gpm) will be for additional purification of the water and would
normally utilize 2-micron filters. Water clarity may not be an issue based on discussions
with other facilities that have re-racked. The filter units will be equipped with filters that
preclude degradation from underwater storage in the transfer canal until the completion
of the project. The initial filter changeout criteria is set for 5 Rem/hr and may be raised
after the project begins when a more representative water sample can be drawn. The
Health Physicist, Radwaste will determine the new criteria based on sample analyses with
the intent of this guidance to avoid producing filters that are greater than Class C waste.
Current projections estimate approximately 30-40 filters will be generated from the re-
rack process.

In-plant filters were also considered during the re-rack planning. Shielding packages
have been developed for the spent fuel purification filters (XFL 6A & 6B) and the
installed purification pump strainer (XST 67). The warehouse has been verified to have
adequate numbers of filters available for changeouts and also has a spare strainer basket
and gasket available in case of buildup of that component. Health Physics intends on
installing remote monitoring on these components.

Reactivity Management regarding boron concentrations in the Spent Fuel pool has been
addressed. Reactor Engineering has calculated a limit of 1000 gallons of demin water
may be added to the spent fuel pool without adversely affecting boron concentrations.
Chemistry procedure CP-618 requires the boron concentration to be maintained between
2000 – 4000 ppm and sampling will be performed as necessary to ensure these limits are
maintained.


Diving Evolutions:
Diver safety is of the utmost importance during this evolution due to the divers proximity
to the spent fuel. To ensure that the diver will be protected, Health Physics has put in
place many safety precautions.




                                              2
Procedures

A specific Health Physics procedure for re-racking/diving, HPP-420, “Radiological
Controls for Spent Fuel Re-Rack”, was developed to ensure the diver’s safety while in
the pool.

Vendor procedures, HSP-30, “Holtec ALARA Plan”, HSP-28 “Holtec Underwater
Diving Procedure” (their dive specific requirements, not health physics requirements),
and Holtec Procedure HPP-1093, “Procedure for On-Site Handling, Installation, and
Removal of Racks for the VC Summer Re-rack Project” will be utilized.

Health Physics practices for controlling work such as RWP usage, multi-badging,
postings, etc. are in accordance with SAP-500 or the applicable Health Physics Procedure
(HPP).

Pre-Job Briefings

For each dive evolution, a pre-dive brief will be conducted and documented in
accordance with the applicable procedures. Checklists also will be used to verify all
actions are complete prior to diving.

Briefs will provide status of work completed from the previous shift, work to be
conducted this shift, job assignments, and radiological conditions of the work area.
Briefs will require all personnel directly involved in the evolution to be in attendance.

Dive Barriers

The diver is to maintain a safe distance of approximately 8 feet from spent fuel
assemblies. This distance will be visually approximated and the actual dive area distance
will be determined by work area surveys. To maintain this approximate distance, a
physical barrier will be placed in the water between the diver and the spent fuel. The
intent of this barrier is to keep the diver from inadvertently entering an unapproved dive
area. In conjunction with the physical barrier, the diver will be continuously monitored
by HP and possibly be restrained by a tether.

Remote Monitoring / Dosimetry

Each diver will be equipped with remote monitoring dosimetry with above surface
readouts that will be continuously monitored by Health Physics. The placement of the
remote dosimetry will be on the diver’s chest, upper arms, and thighs. In addition to the
remote dosimetry, the diver will also be equipped with multiple badge dosimetry. The
diver’s multiple badge locations are on the head, back, chest, thighs, upper arms, groin,
ankles, wrists, and toes/fingers as necessary. Multi-badging is performed in accordance
with HPP-517.




                                              3
The diver will also have an underwater survey instrument with a remote readout with
him. This instrument will be used to verify the work area dose rate during the dive.
Also, the diver will be able to survey items or himself as directed by Health Physics.
Health Physics personnel will have constant communication with the diver at all times.
This communication will be via the dive master. There is also dedicated underwater
camera coverage for monitoring the diver while in the pool. Health Physics will Stop
Work and abort the dive if either the communication or camera coverage is lost.

Fuel Movements

Fuel will be positioned in a manner that maximizes the distance between the diver and
the spent fuel. The final position of the fuel is based on placing older fuel in the cells that
are closest to the diver.

Fuel or highly irradiated material will not be moved while a diver is in the water.

Radiological Surveys

Surveys of the dive area will be conducted prior to each diving operation and following
the movement of any radioactive components stored in the Spent Fuel Pool. Two
independent survey meters will be used to perform surveys of the pool.

A pre-job brief will be held prior to diving. Work area radiological conditions will be
discussed. Only approved dive areas discussed in the brief can be worked in. Industry
events have occurred because the worker performed the task outside an approved dive
area.

During the re-rack evolution, dose rates will be verified on Spent Fuel systems to ensure
potential increases do not affect general area dose rates or create new hot spots. Remote
monitoring dosimeters may be placed on areas where hot spots are expected to occur.

An AMS-4 continuous air monitor will be placed on the Fuel Handling Building 463’
elevation to indicate if airborne activity has increased.

Stop Work Criteria for Diving

Health Physics stop work authority shall consist of, but is not limited to, the following:

1.   Loss of voice communication with the diver,
2.   Loss of camera coverage with the diver,
3.   Loss of breathing air,
4.   Malfunctioning equipment such as alarming dosimeters or survey instruments,
5.   Unexpected increase in survey results,
6.   Any degradation of the safety or radiological controls.




                                               4
Radwaste / Decon:

The cells of each old rack will be pressure washed prior to removal from the water. The
racks will be rinsed with demineralized water while being raised up out of the pool.
Miscellaneous items will be decontaminated via pressure washing or other suitable
cleaning mechanisms, prior to the removal from the Spent Fuel Pool. The boron
concentration will be monitored by Chemistry.

After the old rack is raised out of the Spent Fuel Pool, it will be suspended in the air to
allow the free water to drip off. Next, a diaper will be placed on the bottom of the rack,
to prevent any residual water from dripping off. The rack will then be transferred to the
Decon Pit where it will be lowered into a large bag. The bag will be sealed. The rack
will then be moved to the Train Bay equipment hatch and placed on an upender that will
lower it from a vertical position to a horizontal position. The rack will then be placed in
an oversized shipping container supplied by the vendor.

Holtec is responsible for the disposal of the old racks. The racks will be shored and
shielded as necessary to meet DOT shipping requirements. It is important to place the
rack in the shipping box so the bottom is to the back of the truck to minimize the dose
received by the truck driver. VC Summer personnel will fill out shipping paperwork.
Due to oversize load requirements, special permits will be required.

The site has the responsibility for all dry active waste (DAW) generated during the
project. Current estimations include half a sealand and 30 – 40 filters. This waste will be
disposed of at the completion of the project.

An additional initiative associated with the re-rack project is silica cleanup of the Spent
Fuel Pool. VC Summer is pursuing a vendor to perform this cleanup, however the site
may be responsible for additional waste generated as a result of this process. The
expected waste consists of a few filter screen mechanisms.

Training:
All in-house Health Physics technicians will receive an overview of the project and
Operating Experience during Health Physics Continuing Training (HPCT).

HP personnel assigned to the project will receive specific detailed training provided by
the vendor prior to the start of the job. At the same time, all personnel associated with
the project will receive training on Operating Experience.




                                              5
Benchmarking:
Benchmarking is important in developing and successfully implementing an ALARA
plan. Benchmarking included plant visits to the last two sites that Holtec / Underwater
Construction has performed re-racks, Davis-Besse and Limerick. A substantial number
of lessons learned from other utilities (Waterford, Millstone, Callaway) were also
obtained during these visits. Good practices and lessons learned from these sites were
incorporated into the VC Summer Re-Rack ALARA Plan. Additionally, Holtec provided
a video of a spent fuel rack being removed from the water at Waterford.

Some lessons learned from these other utilities included:

   The use of physical dive barriers
   The use of safe distance approximations from spent fuel
   The use of checklists for technicians in the field
   The use of mockup training for divers
   Problems associated with airborne radioactivity from resubmerging old racks too
    quickly
   Problems associated with the effects of plasma arc cutting on AMP-100 meters
   Shipping requirements – classifications, bracing methods, waste streams, etc
   Problems associated with pressure effects on electronic dosimeter batteries
   Problems associated with the receipt of “Empty” sealand at 1 mile boundary

Industry Events / Operating Experience Review:

Operating Experience provides specially formatted training/briefing material to assist in
preparing personnel to perform plant evolutions. The briefing material for spent fuel re-
racking consists of important industry operating experience as listed:

SER 10-97      Calvert Cliffs, Unplanned Exposure During Spent Fuel Diving Operations

SER 35-88      Calvert Cliffs, Inadequate Work Controls, Work Practices, and Rescue
               Preparations Contribute to Fatality

OE 12107       Seabrook, Accessible Areas not Evaluated for Dose During Re-Rack Mod

OE 11959       Calvert Cliffs, Unexpected and Spurious ED Alarms During Diving

OE 2484        Connecticut Yankee, Unplanned Radiation Exposure

OE 11402       South Texas, Diving Introduces Foreign Material into Spent Fuel Pool

OE 3678        Byron, Hot Particle Exposure Events (2)

IEN 82-31      Indian Point 2, Overexposure of Diver During Work in Spent Fuel Pool



                                             6
SER 03-01       Susquehanna, Highly Radioactive Particles Associated with Fuel Pool
                Work

OE 12184        Braidwood, BPRA Rodlets Found Outside Spent Fuel Racks

OE 11448        DC Cook, Personnel Contamination While Loading Filters into HIC

OE 7344         Quad Cities, Degradation of Tri-Nuc Underwater Vacuum Filters Due to
                Radiation Exposure

NA              LaSalle, Diver lost Breathing Air

These industry events were reviewed for applicability to the re-rack project at VC
Summer. Each event was then summarized with important points and contributors from
those sites and actions listed to prevent occurrence at our site.

A review of the NRC inspection module 86700 “Spent Fuel Activities” was also
performed.

Contingency Plans:

6 areas were identified during the planning of the re-rack project that required
contingency plans. These areas are:

    Higher than Acceptable Dose Rates on Racks – The plan is to slowly lower the rack
     back into the water and pressure wash the higher dose area again. Care should be
     taken to prevent resubmerging the rack too quickly to prevent airborne radioactivity
     due to rapid displacement of air.

    Loss of Communication with the Diver – Any loss of communication with the diver
     will abort the dive.

    Loss of Camera Coverage with the Diver – Any loss of camera coverage on the diver
     will abort the dive.

    Loss of Telemetric Monitoring with the Diver – During diving operations, telemetric
     monitoring at times loses contact. If the hand-held diver survey instrument is
     consistent with the surveyed area, and the rate of exposure to the other telemetry ia as
     expected, the diver may continue his dive. Loss of numerous telemetry points or if
     catastrophic failure of the system occurs, terminate the dive immediately.

    Handling of High Energy Hot Particles - Review of Operating Experience from other
     sites indicated technicians had not received adequate training on the handling of high-
     energy particles. HPP-420 requires if any particle exceeds 5 Rem/hr, attempt to
     remotely secure the particle, control and post the area as necessary and contact the
     Health Physicist, Field Operations / designee for a recovery plan.


                                              7
   Dropped Fuel – Immediate actions for Health Physics include placing the job in a safe
    condition and evacuating the area. Recovery plans and follow-up actions will be
    determined after the event.

Dose Reduction:

The ALARA Plan is intended to keep dose ALARA during the Spent Fuel re-rack
project. Dose reduction can be achieved through planning, scheduling, remote
monitoring, and many other good practices. The following is a recap of items found
throughout this plan.

   Fewer dives are scheduled during the re-rack due to the vast amounts of fuel in the
    pool. Remote tooling advances by the vendor allows for most of the work to be
    performed remotely.

   All of the cells from the old racks will be pressure washed prior to the removal of the
    rack from the water.

   Utilizing cameras for observing or examining items in the pool rather than making a
    separate dive to gather the information.

   Installing shielding and remote dosimetry on plant components such as the filter
    housings and strainers to monitor for increasing dose rates.

   Limit access to reduce or eliminate non-essential personnel in the work area.

   Lessons learned from other plants are incorporated into the VC Summer re-rack plan.
    These lessons learned will also be utilized during pre-job briefings.

RWP’s:

02 – 0039      Perform Fuel Shuffle and Repair Fuel Handling Tools for the Re-Rack
               Project (ECR 50183)

02 – 0157      All Work Associated with ECR 50183 Spent Fuel Re-Rack

02 – 0158      Diving Operations Associated with ECR 50183 Spent Fuel Re-Rack




                                             8
                                                   RE-RACK PROJECT ESTIMATE (TABLE 1)

ACTIVITY                                                          CREW DURATION MAN-HRS    EFFECTIVE           TOTAL
                                                                  (men)  (hrs)          DOSE RATE (mr/hr)   EXPOSURE (mr)


Receive/offload temporary crane                                     7      10    70             0.125           8.75
Offload and upend a new rack (12 times)                             5      5     25 (300)       0.125           37.50
Install the two vertical legs                                       7      20    140            0.125           17.00
Install the 40Ton hoist                                             7      10    70             0.125           8.75
Complete assembly                                                   7      20    140            0.125           17.00
Install fixture, vertical lift each rack to fb463' (12 times)       5      2     10 (120)       0.125           15.00
Relocate a rack to the back of the truck bay (6 times)              5      1     5 (30)         0.125           3.75
Pre-installation drag test each rack (12 times)                     3      7     21 (252)       0.125           31.50
Install bearing pads for each rack (12 times)                       3      6     18 (216)       0.250           54.00
Install each rack (12 times)                                        5      5     25 (300)       0.250           75.00
Remove and store fixture (12 times)                                 5      1     5 (60)         0.250           15.00
Remove or install the temporary crane                               7      3     21             0.125           2.60
SFP floor vacuuming (3 times)                                       2      30    60 (180)       0.250           45.00
Remove existing rack /clean / bag (11times)                         7      5     35 (385) *     3.500          404.25
Down end and package existing rack (11 times)                       7      5     35 (385) #     3.500          269.50
Post drag test each rack (13 times)                                 2      8     16 (208)       0.250           52.00
Disassemble the temporary crane                                     7      30    210            0.125           26.25
HP Support                                                          2     800    1600           0.063          100.00
Decon Support                                                       3     1000   3000           0.063          187.50
New rack installation in cask pit                                   5      8     40             0.250           10.00


* 30% of time at rack                                                                           Total          1380.35
# 20% of time at rack



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      Figure 2
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     Date
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