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10 CFR 72 AUG17 1990

1. a. CERTIFICATE NUMBER: 1003

b. REVISION NUMBER: 0

c. PACKAGE IDENTIFICATION NUMBER: USA/72-1003

d. PAGE NUMBER: 1

e. TOTAL NUMBER OF PAGES: 3

2. Preamble This certificate is issued to certify that the cask and contents,

described in item 5 below, meets the applicable safety standards set forth in Title

10, Code of Federal Regulations, Part 72; "Licensing Requirements for the Independent Storage of Spent Nuclear Fuel and High-Level Radioactive Waste."

3. THIS CERTIFICATE is issued on the basis of a safety analysis report of the

cask design.

a. PREPARED BY (Name and Address) b. TITLE AND IDENTIFICATION

OF REPORT OR APPLICATION

Nuclear Assurance Corporation Topical Safety Analysis Report

6251 Crooked Creek Road for the NAC Storage/Transport Cask

Suite 200 Containing Consolidated Fuel for

Norcross, GA 30092 use at an Independent Spent Fuel

Storage Installation

c. DOCKET NUMBER 72-1003

4. CONDITIONS This certificate is conditional upon fulfilling the requirements of 10

CFR 72, as applicable, and the conditions specified below.

5. Cask

a. Model No: NAC-C28 S/T

b. Description

The Nuclear Assurance Corporation Storage/Transport cask for consolidated fuel

(NAC-C28 S/T) is designed for the storage and shipment of irradiated fuel rods

placed in canisters. This certificate addresses spent fuel handling, transfer, and

storage on an NRC-licensed nuclear reactor site but does not address any use

of this cask for offsite transport of spent fuel.

0C.)9 ; 1 c)032z~7 90081 - t7

PDR PROJ

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AUG 1 7 1990

The NAC-C28 S/T is a multi-wall cylinder with a 38.86 mm (1.53 in) thick inner

shell and a 66.07 mm (2.68 in) thick outer shell, both made of stainless steel,

separated by 81.3 mm (3.2 in) of lead. There is a 177.8 mm (7.0 in) thick solid

neutron shield around the outer shell which is encased in 6.35 mm (.25 in) thick

stainless steel. The cask body is 4605 mm (181.3 in) long and 2419 mm (95.24

in) in diameter. The loaded cask including fuel, water, and lifting yoke weighs

less than 113 tonne (125 tons), empty it weighs approximately 75 tonne (83

tons). The fuel basket has 28 cavities which are 223 mm (8.78 in) square for

storage of PWR fuel assemblies. Six trunnions can be attached to the cask, four

around the top and two opposite each other near the bottom.

Gamma and neutron radiation is shielded by the lead, stainless steel, and Bisco

(solid neutron shield) in the wall. The bottom and lid are also made of lead encased in a stainless steel shell. A 96.5 mm (3.8 in) thick stainless steel and Bisco neutron shield cap is placed on top of the cask after fuel loading to further

reduce radiation.

The cask is sealed, to maintain an inert helium atmosphere, using a 215.9 mm

(8.5 in) thick lid with two metallic O-rings. The lid is secured by 24 bolts. The lid

has four penetrations: (1) cask cavity drain, (2) cask cavity vent, (3) interseal

test port, (4) interseal pressure transducer. Each is sealed using two metal

O-rings.

The 28 fuel cavities are square aluminum tubes tubes which are held by aluminum castings at its periphery. Sheets of boral are attached to the outside of the

tubes to absorb neutrons.

Impact limiters are attached to the top and bottom of the cask during transport

and storage. They are made of Aluminum honeycomb inside a stainless shell.

The cask may never be lifted higher than 59 inches and must be moved in a

vertical position.

c. Drawing

The NAC-C28 S/T cask is described by drawings in Chapter 4 of the TSAR.

d. Basic Components

The Basic Components of the NAC-C28 SIT cask, that are important to safety,

are listed in Section 3.4 of the TSAR.

6. Cask fabrication activities shall be conducted in accordance with the reviewed and

approved quality assurance program submitted with the TSAR.

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7. Notification of cask fabrication schedules shall be made in accordance with the requirements of §72.232(c), 10 CFR Part 72.

8. Casks of the Model No. NAC-C28 S/T authorized by this certificate are hereby approved for general use by holders of 10 CFR Part 50 licenses for nuclear reactors

at reactor sites under the general license issued pursuant to §72.210, 10 CFR Part

72, subject to the conditions specified by §72.212 and the attached Conditions for

Cask Use.

9. Expiration Date: FOR THE NUCLEAR REGULATORY COMMISSION

August 31, 2010

'1NATURE

Chief, Fuel Cycle Safety Branch

Division of Industrial and

Medical Nuclear Safety

Office of Nuclear Material Safety

and Safeguards

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CONDITIONS FOR CASK USE

CERTIFICATE OF COMPLIANCE

72-1003
TABLE OF CONTENTS

Page

1.0 INTRODUCTION .....................................................

1.1 General Conditions ..........................................

1.2 Preoperational Conditions ...................................

2.0 FUNCTIONAL AND OPERATING LIMITS ..................................

2.1 Fuel To Be Stored At ISFSI ..................................

2.2 NAC-C28 S/T Dry Storage Cask ................................ 2.3 Limiting Condition - Handling Height ........................ 2.4 Dry Storage Cask Surface Contamination ......................

2.5 Dry Storage Cask Internal Cover Gas .........................

3.0 SURVEILLANCE REQUIREMENTS ........................................

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3.1

3.2

3.3

3.4

3.5

3.6

3.7

Cask Loading Measurements .

Cask Seal Testing ......... Cask Contamination ........ Dose Rates ................ Safety Status Surveillance

Cask Interseal Pressure ...

Alarm System...............

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1.0 lNTRODUCTION

These Conditions for Cask Use govern the safety of the receipt possession and

storage of irradiated nuclear fuel at an Independent Spent fuel Storage

Installation (ISFSI) and the transfer of such fuel to and from a Nuclear Power

Station and its ISFSI.

1.1 GENERAL CONDITIONS

1.1.1 Operating Procedures

Written operating procedures shall be prepared for cask handling, movement,

placement, surveillance, and maintenance.

1.1.2 Quality Assurance

Activities at the ISFSI shall be conducted in accordance with the requirements

of Appendix B, 10 CFR Part 50.

1.2 PREOPERATIONAL CONDITIONS

The user shall not allow the initial loading of spent nuclear fuel in the Model

Number NAC-C2B S/T cask until such time as the following preoperational license

conditions are satisfied:

(1) A training module shall be developed for the Station Training Program

establishing an ISFSI Training and Certification Program which will

cover the following:

a. Cask Design (overview)

b. ISFSI Facility Design (overview)

c. ISFSI Safety Analysis (overview)

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d. Fuel loading and cask handling procedures and abnormal

procedures

e. Certificate of Compliance (overview).

(2) A training exercise (Dry Run) of cask loading and handling activities

shall be held which shall include but not be limited to:

a. Moving cask in and out of spent fuel pool area.

b. Loading a consolidated fuel canister (using a dummy canister).

c. Cask sealing and cover gas backfilling operations.

d. Moving cask to and placing it on the storage pad.

e. Returning the cask to the reactor.

f. Unloading the cask assuming fuel cladding failure.

g. Cask decontamination.

2.0 FUNCTIONAL AND OPERATING LIMITS

2.1 FUEL TO BE STORED AT ISFSI

2.1.1 Specification

The spent nuclear fuel to be received and stored at the ISFSI in NAC-C28 S/T

casks shall meet the following requirements:

(1) Consolidated Zircaloy clad PWR fuel rods in canisters that have the

characteristics listed in Table 10.1-1 of the TSAR may be stored in

the NAC-C28 S/T cask. The maximum number of canisters that may be

stored is 28.

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(2) Maximum initial enrichment shall not exceed 3.5 weight percent U-235.

(3) Maximum assembly average burnup shall not exceed 35,000 megawatt days

per metric ton uranium.

(4) Maximum heat generation rate shall not exceed .714 kilowatt per fuel

canister.

(5) Fuel canisters shall contain no fewer than 361 fuel rods and no more

than 408 fuel rods.

(6) Fuel canisters known or suspected to have structural defects

sufficiently severe to adversely affect fuel handling and transfer

capability shall not be loaded into the cask for storage.

(7) A procedure shall be developed for the documentation of the

characterizations performed to select spent fuel to be stored in the

casks. Such procedure shall include independent verification of fuel

and canister selection by an individual other than the original

individual making the selection.

(8) Immediately prior to insertion of a spent fuel canister into a cask,

the identity of the canister shall be independently verified by two

individuals.

2.1.2 Basis

The design criteria and subsequent safety analysis assumed certain

characteristics and limitations for the fuels that are to be received and

stored. Specification 2.1.1 assures that these bases remain valid by defining

the type of spent fuel, maximum initial enrichment, irradiation history, and

maximum thermal heat generation.

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2.2 NAC-C28 S/T DRY STORAGE CASK

2.2.1 Specification

NAC-C28 S/T Dry Storage Casks used to store spent nuclear fuel at an ISFSI

shall have the operating limits shown in Table 2-1.

2.2.2 Basis

The design criteria and subsequent safety analysis of the NAC-C28 S/T assumed

certain characteristics and operating limits for the use of the casks. This

specification assures that those design criteria are not exceeded.

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Table 2-1 NAC-C28 S/T OPERATING LIMITS

Operating Limit

Max. Lifting Height with a Nonredundant

Lifting Device

With Impact Limiters

Without Impact Limiters

< 4 feet, 11 inches

< 15 inches

Dose Rate

. 2 m Distance

* . Surface

• 10 mrem/hr

g 200 mrem/hr

Cask Tightness

(Standard He-Leak Rate)

* Primary Lid Seal

. Secondary Lid Seal

Max. Specific Power of one Fuel Canister

• 10-6 atm cm3/sec

• 10-6 atm cm3/sec

.714 kW

Initial Helium Pressure Limit (Cask Cavity) 32.4 psia

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2.3 LIMITING CONDITION - HANDLING HEIGHT

2.3.1. Specification

This specification applies to the handling of a loaded cask outside of the Fuel

Building and Crane Enclosure Building.

(1) The NAC-C28 S/T cask shall not be lifted higher than 59 inches.

(2) The NAC-C28 S/T must always be handled in a vertical orientation.

(3) The bottom impact limiter must be used when handling a loaded cask

above a height of 15 inches.

2.3.2 Basis

The drop analyses performed for the NAC-C28 S/T dry storage cask requires these

conditions to avoid sustaining unacceptable damage to the storage cask and fuel

basket in the event of a cask drop. This limiting condition ensures that the

handling height limits will not be exceeded at the storage pad or in transit to

and from the reactor.

2.4 DRY STORAGE CASK SURFACE CONTAMINATION

2 4.1 Specification

Initial removable surface contamination shall not exceed 2200 dis/min/100 cm2

from beta-gamma sources, and 220 dis/min/100 cm2 from alpha sources.

2.4.2 Basis

Compliance with this limit ensures that the decontamination requirements of

49 CFR 173.443 will be met.

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2.5 DRY STORAGE CASK INTERNAL COVER GAS

2.5.1 Specification

The dry storage casks shall be backfilled with helium.

2.5.2 Basis

The thermal analysis performed for the dry storage casks assumes the use of

helium as a cover gas. In addition, the use of an inert gas (helium) is to

ensure long-term fuel clad integrity.

3.0 SURVEILLANCE REQUIREMENTS

Requirements for surveillance of various radiation levels cask internal

pressure, contamination levels, cask seal leak rates, and fuel related parameters are contained in this section. These requirements are summarized in

Table 3-1 from details contained in Section 3.1 through 3.6. Specified time

intervals may be adjusted plus or minus 25 percent to accommodate normal test

schedules.

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Table 3-1 SURVEILLANCE REQUIREMENTS SUMMARY

Section Quantity or Item Period

3.1.1 Cask Loading Measurements P

3.2.1 Cask Seal Testing L

3.3.1 Cask Contamination L

3.4.1. Dose Rates (Cask surface or up to 2 meters L

from cask surface)

Dose Rates (Fence) Q

3.5.1 Safety Status Surveillance Q

3.6.1 Pressure Transducer System Parameters P & L

3.7.1 Alarm System A

P - Prior to cask loading

L - During loading operations

Q - Quarterly

A - Annually

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3.1 CASK LOADING MEASUREMENTS

3.1.1 Specification

For the first loading of a cask model, cask side-wall surface dose rate shall

be measured upon cask draining. Prior to moving the cask to the storage pad,

cask surface temperature shall be measured after the cask has been sealed for

an appropriate period, which should not be less than that expected for the

cask surface temperature to come into approximate equilibrium. These dose

rate and temperature measurements shall be made at the cask side-wall mid-line

at three locations 1200 apart around the cask circumference and shall be

recorded to establish a baseline of comparison for all subsequent loadings of

this model of cask.

For all subsequent loadings of casks of this model, measure and record cask

side-wall surface dose rates and temperatures at the cask side-wall mid-line

at three locations 1200 apart and compare these to the baseline established

during first cask use. Do not transfer the cask to the storage pad if

unexplained variations (which can not be resolved through known differences

in spent fuel assemblies loaded) are found.

3.1.2 Basis

These measurements are to assure that casks have been properly loaded.

3.2 CASK SEAL TESTING

3.2.1 Specification

Prior to storage, the cask seals must be tested as specified in Section

3.3.2.2 of the TSAR.

3.2.2 Basis

The safety analysis of leak tightness of the cask as discussed in the topical

report is based on the seals being leak tight to 10-6 atm cm3/s. This check

is done to ensure compliance with this design criteria.

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3.3 CASK CONTAMINATION

3.3.1 Specification

After cask loading and prior to moving the cask to the storage pad, the cask

shall be swiped to ensure that removable surface contamination levels are less

than 2200 dis/min/100 cm2 from beta-emitting sources, and 220 dis/min/100 cm2

from alpha emitting sources.

3.3.2 Basis

This surveillance requirement will ensure compliance with the decontamination

requirements of 49 CFR 173.443 prior to storage in the ISFSI.

3.4 DOSE RATES

3.4.1 Specification

The following dose rate measurements shall be made for the ISFSI:

(1) Cask Surface Gamma and Neutron Dose Rates: After completion of cask

loading, gamma and neutron measurements shall be taken on the outside

surface (or within 2 meters of the cask surface). The combined gamma

and neutron dose rates shall be less than the surface dose rate stated

in Table 2-1 (or the specified rate a distance of up to 2 meters from

the cask surface).

(2) Dry Cask ISFSI Boundary: Doses shall be determined by measurement at

the Dry Cask ISFSI site fence and shall be evaluated on a quarterly

basis to demonstrate compliance with §20.105, 10 CFR Part 20.

3.4.2 Basis

These measurements are necessary to assure compliance with the cask

specifications and that the dose rates at the security fence meet Part 20

limits as additional casks are placed in storage.

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3.5 SAFETY STATUS SURVEILLANCE

3.5.1 Specification

A visual surveillance shall be performed on a quarterly basis of the ISFSI to

determine that no significant damage or deterioration of the exterior of the

emplaced casks has occurred. Surveillance shall also include observation to

determine that no significant accumulation of debris on cask surfaces has

occurred.

3.5.2 Basis

This surveillance requirement shall ensure cask maintenance.

3.6 CASK INTERSEAL PRESSURE

3.6.1 Specification

The cask interseal pressure shall be monitored by use of a pressure transducer

system as described in section 3.3.3.2 of the TSAR.

3.6.2 Basis

This specification requires the interseal space to be monitored to detect any

leakage of either cask seal.

3.7 ALARM SYSTEM

3.7.1 Specification

An alarm system to which all of the pressure transducer systems are connected

shall be installed at the storage site and functionally tested annually to

ensure proper operation of the system.

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3.7.2 Basis

The alarm system must be capable of alerting surveillance personnel of possible

cask seal failure and must permit identification of the specific cask

indicating a seal failure.

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