ML20216E172

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Application for Amend to License DPR-3,modifying Defueled TS 3.1.3 to Allow Util to Continue W/Implementation of Ynps Decommissioning Plan Which Has Been Incorporated Into Ynps FSAR
ML20216E172
Person / Time
Site: Yankee Rowe
Issue date: 09/05/1997
From: Stephen Schultz
YANKEE ATOMIC ELECTRIC CO.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20216E178 List:
References
BYR-97-044, BYR-97-44, NUDOCS 9709100106
Download: ML20216E172 (16)
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. YANKEE ATOMICELECTRIC COMPANY "Ql,1**g%'?,*p'"

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580 Afain Street, Bolton. Massachusetts 01740-1398 s___. .

September 5,1997 BYR 97-044 United States Nuclear Regulatory Commission Document Control Desk Washington, DC 20555 Attention: Mr. Morton B. Fairtile, Project Manager

References:

(a) License No. DPR-3 (Docket No. 50-29)

(b) Letter, A. Kadak, Yankee Atomic Electric Company (YAEC) to T.

Murley, U.S. Nuclear Regulatory Commission (NRC), dated December 20, 1993 (c) Generic Licensing Topical Report, EDR-1 (P)-A, "Ederer's Nuclear Safety Related extra-Safety And Monitoring (X-S AM) Cranes,"

Revision 3, dated October 8,1982, Amendment 3 (d) Letter, J. Zwolinski, NRC to J. Kay, YAEC, dated February 19,1985 (e) NUREG 0554, " Single Failure-Proof Cranes for Nuclear Power Plants,"

May 1979 (f) NUREG-0612, " Control of Heavy Loads at Nuclear Power Plants,"

January 1980

Subject:

Spent Fuel Pit - Crane Travel and Water Level Technical Specification Changes

Dear Mr,

Faittile:

Pursuant to Section 50.90 of the Commission's Rules and Regulations, Yankee Atomic Electric Company (YAEC) hereby proposes the following modification to Appendix A cf the Facility Possession Only Licent.e (Reference (a)).

EROPOSED CHANGE Reference is made to the Defuelcd Technical Specifications of the Yankee Nuclear Power Station (YNPS) Possession Oidy License, DPR-3. YAEC proposes to modify the Defueled Technical Specifications as follows:

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l. Add new Defueled Technical Specification 3.1.3 as follows:

3.1.3 Irradiated fuel assemblies may be transported in or out of the spent fuel pit, \ k without the minimum 5 feet of water over the top of the irradiated fuel assemblies, when they are transported within a shipping and/or transfer cask.

9709100106 970905 R ADOCK 05000029 -

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. United States Nuclear Regulatory Commission t September 5,1997  :

Page 2 s- - 2. ' Revise Bases for Defueled Technical Specification 3/4.1." Spent Fuel Pit Water Level" as follows:

~ Add new paragraph: "When spent fuel is tiansported in or out of the spent fbel pit within a shipping and/or transfer cask, shielding for personnel exposure is provided by the cask systemc The cask system ensures that exposure to personnel will be maintained ALARA."

3. Revise Defueled Technical Specification 3.2 to read as follows:

- Delete:

e. Temporary gate,
f. Shielding panels, .
i. Shipping casks: 35 tons maximum gross weight - not for spent fuel, and Add:
e. Cask components and associated lifting devices,

- f. Shipping and/or transfer casks: 80 tons maximum gross weight on Yard Area Crane,

1. Cask set-down pad, and
4. Revise Defueled Technical Specification 4.2,1.a as follows:

Delete existing paragraph. Replace with " Spent Fuel Storage Building roof hatches, spent fuel inspection stand, fuel handling equipment, spent fuel racks, spent fuel asserrbly_

nondestructive test equipment, cask set-down pad, shipping cask liners, volume reduction equipment, cask components and associated lifting devices, and shipping and/or transfer casks may travel over the spent fuel pit in accordance with approved written procedures;". .

5. Revise Defueled Technical Specification 4.2.1.b as follows:

Delete existing paragraph. Replace with "The volume reduction equipment, the spent fuel inspection stand, and the spent fuel assembly nondestructive test _ equipment shall be

- prevented from traveling over fuel assemblies in the spent fuel pit by administrative control. ' The volume reduction equipment (when transported by the Yard Area Crane),

the shipping cask liners, the cask set-down pad, and the shipping and/or transfer casks shall be prevented from traveling over fuel assemblies in the spent fuel pit by administrative control and by the Yard Area Crane travel limit switch, which prevent movement of these loads beyond the southern end of the safe load path. The cask hatch cover and the cask components and associated lifting devices shall be prevented from

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, United States Nuclear Regulatory Commission

' September 5,1997

, Page 3 traveling over spent fuel assemblies stored in the spent fuel pit by administrative control and by the Yard Area Crane travellimit switch, except that the cask hatch cover and the cask components and associated lifting devices may be allowed over the spent fuel

, assemblies in the shipping and/or transfer cask when used in conjunction with cask operations; and" l 6. Revise Bases for Defueled Technical Specification 3/4.2 " Crane Travel - Spent Fuel Pit" as follows:

a.) Delete "the temporary gate, the shielding panels," from second paragraph b.) In the second paragraph, replace "the shipping cask liners, and the shipping casks" with "and the shipping cask liners" c.) Add new paragraph: "The use of a single-failure-proof crane provides assurance

, that a credible single failure will not result in the shipping and/or transfer cask, the cask set-down pad, the cask hatch cover, and the cask components and associated

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lifting devices having an adverse effect on the spent fuel pit or the irradiated fuel in the spent fuel pit. The restriction on movement of the shipping and/or transfer

cask, the cask set-down pad, the cask hatch cover, and the cask components and lifting devices further ensures that these items cannot be dropped on spent fuel in the spent fuel pit storage racks, The use of a single- failure-proofcrane ensures that the cask hatch cover and the cask components and associated lifting devices, which are permitted over the spent fuel in the cask, cannot be dropped on the spent fuel. The safe load path is established to support the defense-in-depth approach to safety concerning heavy loads over the spent fuel pit. Deviations from or changes to the safe load path shall be performed in accordance with approved written procedures which have been approved by PORC. "

Revised Technical Specification and bases pages are provided in Attachment B.

REASON FOR CHANGE l

These changes to the Defueled Technical Specifications are proposed to allow YAEC to continue with the implementation of the YNPS decommissioning plan (Reference (b)), which has been incorporated into the YNPS FSAR. More specifically, the proposed changes will allow YAEC to transport spent fuel and greater than Class C (GTCC) waste from the spent fuel pit (SFP) to either a temporary on-site dry storage area or to an offsite storage facility or repository. The removal of spent fuel and GTCC waste will then allow the SFP and its associated support systems to be decontaminated and/or dismantled in accordance with the YNPS decommissioning plan and FSAR.

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- United Stntes Nuclear Regulatory Commission -

t September 5,1997 -

Page 4 The specific reasons for each of the six proposed changes (from last section) t'o the YNPS Defueled Technical Specifications are as follows:

Prononed Changen 1 & 2: Defueled Technical Snarificatinn (DTS) 31.3 and Banen 3/4.1

1. To provide new DTS 3.1.3 to remove the requirement for at least five (5) feet of water over irradiated fuel in the SFP when being transported within the shipping and/or transfer cask. This change takes credit for the shielding provided by the shipping and/or transfer [

cask systems to provide personnel exposure protection.

2. -

To reflect in Bases 3/4.1 that the shielding for personnel protection will be provided by the shipping and/or transfer cask systems, when fuel is transported within the shipping and/or transfer cask. The bases was also changed to document that the shipping and/or transfer cask system is designed to maintain personnel exposure ALARA.

ProponaA Changen i 4. 5 & 6: DTS 3.2. Surveillance Reauirementa 4.2.1 4& 4.21.b.

and Banaa 3/4.2

3. . To change DTS 3.2 to increase the maximum weight limit for the allowed load (when n

using the Yard Area Crane) over the SFP, and to remove the restriction prohibiting casks

- for spent fuel from travel over the SFP This change is also proposed to allow the travel of the cask set-down pad, cask components and associated liAing devices over the SFP, In addition, a change was made to remove the temporary gate and shielding panels from being allowed to travel over SFP since these components are no longer used for SFP operations.

4, To change Surveillance Requirement 4.2.1.a to specify that the shipping and/or transfer cask, cask set-down pad, cask components and associated liAing devices are only allowed to be moved over the SFP in accordance with approved written procedures and to reflect that the temporary gate and shielding panels are no longer used.

5. - To change Surveillance Requirement 4.2.1.b to specify that the shipping and/or transfer casks, cask set-down pad, cask hatch cover (i.e. SFP building roof hatch), and cask

- components and associated lifting devices shall be prevented from movemen: over the -

fuel assemblies stored in the SFP racks by both administrative control and the Yard ' Area Crane travel limit switch. The Surveillance Requirement was changed to clarify when the Volume Reduction Equipment was prevented from traveling over fuel assemblies in the I SFP by administrative control only and when both administrative control and the Yard Area Crane travel limit switch applied. The Surveillance Requirement was also modified to reflect the deletion of the temporary gate and shielding panels.

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United States Nuclear Regulatory Commission

' September 5,1997 Page 5

6. To change Bases 3/4.2 to clearly reflect that the shipping and/or transfer cask, cask set-down pad, cask hatch cover, and cask components and associated lifting devices are restricted from movement over the spent fuel assemblies stored in the SFP racks, and to specify that the cask hatch cover, and cask components and associated lifting devices are permitted over spent fuel assemblies which are contained within the shipping and/or transfer casks, when these casks are being used to transport fuel assemblies in or out of the pool.

Bases 3/4.2 was also changed to specify that the single-failure-proof design of the crane provides the protection required for handling of the heavy loads added to Defueled Technical Specification 3.2 for travel over the SFP. A specific statement is added to the bases to clarify that changes and/or deviations to the safe load path, are permitted, provided they are performed in accordance with approved procedures that have been approved by PORC. This is consistent with NUREG-0612. In addition, the change removed the reference to the temporary gate and shielding panels which are no longer used.

BASIS FOR CHANGE In preparation for moving spent fuel and/or GTCC waste to either a temporary on site dry storage area or to an offsite storage area, YAEC will upgrade its cask handling crane (Yard Area Crane) to a single-failure-proof crane design for loads up to 80 tons. NUREG-0612, " Control of Heavy -

Loads at Nuclear Power Plants," (Reference (f)), provides criteria for load handling operations in the spent fuel pool area. The single-failure-proof crane design,- the requirements specified in Sections 5.1.1 and 5.1.6 of NUREG-0612, and the additional design and administrative controls to prevent travel over the stored fuel assemblies in the SFP provide a level of defense-in-depth that ensures that dropping of a heavy load is not a credible event.

The current Defueled Technical Specifications requirements ensure that YNPS implements the NUREG-0612 criteria with Technical Specification limitations on loads that are permitted to travel over the SFP and with requirements for administrative controls to ensure that the Spent Fuel Storage Building roof hatches and fuel handling equipment are moved only within their '

allowed boundaries. Because YAEC had previously deferred addressing NUREG-0612 criteria for moving spent fuel casks, a restriction preventing movement ofcasks containing spent fuel over the SFP was added to the current Technical Specifications. This restriction prevented spent fuel cask movement until YAEC finalized the method it would utilize to ensure casks containing spent

- fuel were stely operated and cor trolled. The following paragraphs provide the design and operational bases for removing ths restriction and allowing the use of spent fuel casks (shipping and/or transfer casks) for loads up to 80 tons over the SFP.

To ensure the safe transfer of shipping and/or transfer casks, the cask handling crane is being -

upgraded to meet the single-failure-proof requirements of NUREG-0554, " Single-Failure-Proof

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United States Nuclear Regulatory Commission

' September 5,1997 l Page 6

, Cranes for Nuclear Power Plants," (Reference (e)), as further clarified in NUREG-0612, l Appendix C for existing cranes. The single-failure-proof crane design, along with administrative

and design controls, will assure safe handling of the shipping and/or transfer casks. The crane is also being upgraded to handle loads up to 80 tons on the main hoist. This includes upgrading of l instruments and controls, replacement of the existing bridge and trolley, main and auxiliary hoist motors, brakes, and controls.

I The upgraded crane is being purchased from Ederer, Incorporated, The crane will conform to the specifications of Generic Licensing Topical Report EDR-1(P), Revision 3, "Ederer Nuclear Safety Related extra Safety And Monitoring (X-SAM) Cranes," (Reference (c)). This Topical Report documents the NRC review and generic licensing acceptance of Nuclear Safety Related X-SAM Cranes for use in single-failure-proof applications in existing facilities. The NRC's review and acceptance of the Ederer's X-SAM Crane submittal addressed the following characteristics: -

Special hoist safety systems and components,

  • Compliance with applicable regulatory positions,
  • Operation test provisions,
  • Single-failure-analysis, and
  • Envelope of design characteristics.

The X-SAM Crane design utilizes three types of systems for protection against malfunctions and misoperation. A discussion of these systems is provided in Attachment A.

- As stated in the Topical Report, the Ederer X-SAM Crane design features are " acceptable for assuring that a single failure will not result in the loss of capability to safely retain a critical load" for the hoisting system and brake system for trolley and bridge. Plant specific details, as delineated in Appendices B and C of the Topical Report, will be addressed and incorporated into the YNPS FSAR; This will ensure that the crane conforms with the Topical Report requirements, which have been found acceptable for meeting the single-failure-proof design as specified in NUREG-0554 and Regulatory Guide 1.104 (later withdrawn and replaced by NUREG-0554),

With the upgrade of the crane to a single-failure-proof design, the Technical Specification requirements limiting casks to a load of 35 tons and prohibiting movement of spent fuel in casks i over the SFP can be revised to allow for the safe transfer and removal of the spent fuel and GTCC waste from the SFP for loads up to 80 tons. Removing the spent fuel and GTCC waste from the SFP will allow for continued decommissioning of the YNPS in accordance with the NRC-approved Decommissioning Plan (Reference (b)) and FSAR. Direct shipment of the spent fuel and GTCC waste to an offsite repository is the preferred option. However, if an offsite repository is not available in the near future, YAEC must ensure that spent fuel and GTCC waste

e United States Nuclear Regulatory Commission

- September 5,1997 Page 7 can be transferred to a temporary on-site dry storage facility.

The addition of the cask set-down pad and the cask components and associated lifting devices to

- the Defueled Technical Specifications are all needed to support activities that are necessary to support movement of the shipping and/or transfer casks. The change delineating when the Volume Reduction Equipment is administratively controlled and when it la controlled both

- administratively and by the Yard Area Crane travel limit switch is made to clarify the intent of the requirement.- The removal of the temporary gate and shielding panel from the Defueled Technical Specification reflects that these components are no longer utilized in SFP operations.

To provide the clearance needed to transfer the larger diameter transfer cask, modifications to -

the SFP building superstmeture and the cask hatch cover are necessary. Part of these l - modifications will relocate the steel framing beam that previously protected the loads from moving over fuel in the SFP. As such, this steel beam will no longer prevent movement of the heavy load past the safe load path. To maintain an equivalent level of safety, the upgraded crane will be provided with a crane travel limit switch that will be set to prevent movement of the prohibited heavy loads past the south end of the safe load path. A statement was added to the basis to specify and provide clarity on what is required to change and/or deviate from the safe

. load path. This guidance is consistent with the guidance of NUREG-0612, concerning deviations from the safe load path.

SAFETY CONSIDERATIONS A safety assessment has been performed to address the proposed Technical Specification changes to remove the cask handling restriction relative to "not for spent fuel" and the modification to -

use a spent fuel cask in conjunr: ion with the cask handling crane upgrade to a single-failure-proof crane. An assessment of the following attributes is presented below:

  • Criteria Pertaining to the Use of a Single-Failure-Proof Crane
  • Increased Load Capacity and Additional Loads
  • Accident Assessment
  • Shielding for Minimizing Personnel Exposure

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Regulatory Guide 1.13 provides an acceptable method ofmeeting 10 CFR 50, Appendix A, General Design Criteria (GDC) 61, " Fuel Storage and Handling Criteria for Nuclear Power

United States Nuclear Regulatory Commission

  • September 5,1997 Page 8 Plants" concerning heavy loads over spent fuel pools. This Regulatory Guide recognized that spent fuel cask loads of about 100 tons would need to be placed in spent fuel pools. In order to assure safety, Regulatory Guide 1.13 proposes three different acceptable methods for handling of heavy loads over a spent fuel pool. One of the acceptable methods is stated as follows:

" Cranes should be designed to provide single-failure-proof handling of heavy loads, so that a single failure will not result in loss of capability of the crane-handling system to perform its safety function."

NUREG-0612, " Control of Heavy Loads at Nuclear Power Plants," also provides direction regarding load handling. Specifically NUREG-0612 states that ". . . to provide assurance that the evaluation criteria of Section 5.1 (of NUREG-0612) are met for load handling operations in the spent fuel pool area, in addition to satisfying the general guidelines of Section 5.1.1, one of the following should be satisfied." The first method proposed is:

) "The overhead crane and associated lifting devices used for handling heavy loads in the spent fuel pool area should satisfy the single-failure-proof guidelines of Section 5.1.6 of this report."

By upgrading the cask handling crane to meet the single-failure-proof criteria of NUREG-0554, YAEC will provide an acceptable method (as specified in Regulatory Guide 1.13 and NUREG-0612) of ensuring that heavy loads can be moved safely over the spent fuel pit. YAEC also utilizes a crane travel limit switch to ensure that the cask handling crane heavy loads, prohibited by Technical Specification 4.2.1.b from movement over the irradiated fuel assemblies stored in SFP storage racks, are prevented from traveling over any of the irradiated fuel assemblies stored in the SFP racks. In addition, administrative controls, including crane operating procedures, will be implemented to ensure that heavy load movement over or around the SFP is controlled in accordance with the Technical Specification requirements.

Soecific Design Criteria from NUREG-0612 The single-failure-proof crane design, the requirements specified in Sections 5.1.1 and 5.1.6 of NUREG-0612, and the additional design and administrative controls to prevent travel over the stored fuel assemblies in the SFP provide a level of defense-in-depth that ensures that dropping a heavy load remains a non-credible event. In addition to making the crane single-failure-proof, YAEC will establish procedures and controls to meet the requirements of Sections 5.1.1 and 5.1.6 ofNUREG-0612. Theseinclude:

1. A safe load path for the movement of heavy loads, around the SFP, has been established and is defined in the current crane operating procedure. The safe load path was established for moving casks in and out of the SFP and was previously reviewed and

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United States Nuclear Regulatory Commission

' September 5,1997 Page 9 accepted by the NRC for a prior cask movement at YNPS (Reference (d)). YAEC previously modified the SFP Building to provide side entry access to the building. This minimized the height (lowered from 52 feet to 38 feet above the SFP floor) requirei, for moving a cask into and out of the SFP. To account for the braking distance afforded by the single-failure-proof crane this distance will need to be raised slightly, but will be maintained less than 39 feet above the SFP floor. The safe load path, which prohibits movement of heavy loads over the fuel assemblies in the SFP storage racks, is provided as an attachment to the crane operating procedure. This safe load path will become larger to accommodate a larger diameter cask. This will increase the safe load path in the southern direction; however, the safe load path will not permit the cask to travel over the fuel in the fuel storage racks. NUREG-0612 delineates that certain measures may be taken to compensate for situations where heavy loads will be brought into the vicinity ofirradiated fuel. The single-failure-proef ciane and the lining devices with redundant or increased safety factors provide an adequate alternate measure to ensure that sufficient protection is provided. However, to maintain a defense-in-depth approach, the safe load path will be maintained by administrative control and by a crane travel limit switch (at the southern end) euch that the movement of the prohibited heavy loads by the cask handling crane will be prevented from travel over the spent fuelin the storage racks. Because the crane is outdoors, it is not practical to mark the safe load path. Instead, a designated signalman is used to dirket all crane movements. This use of the signalman, instead of providing permanent marking on the floor, was determined to be a " reasonable alternative" by the NRC (Reference (d)).

2. Procedures for the safe handling of heavy loads over the SFP will be established. YAEC currently has approved procedures in place for handling the SFP roof hatches. In addition, YAEC will develop new procedures for handling the shipping and/or transfer cask, cask set-down pad, cask components and associated lining devices. The procedures will be developed with the precautions and directions necessary to ensure that the design limitations associated with the single-failure-proofdesign are not exceeded. Specific procedures to direct rigging and crane operation will be provided to delineate operation of the crane and the associated lining devices. These procedures will contain cautions and limitations to provide further assurance that the loads which are prohibited from movement over the spent fuel will not be moved over spent fuel, and that the loads which are permitted over spent fuel are only allowed over the spent fuel when the specified Technical Specification conditions are met.
3. Crane operators will be trained, qualified and instructed to conduct themselves in accordance with Chapter 2-3 of ANSI B30.2-1976, " Overhead and Gantry Cranes."
4. Special lining devices will satisfy the guidelines of ANSI N14.6-1978, " Standards for Special Lining Devices for Shipping Containers Weighing 10,000 Pounds or More for

United States Nuclear Regulatory Commisi, ion

' September 5,1997 Page 10 Nuclear Materials," for heavy loads. Where a single, special lining device is used, YAEC will ensure that the specialliaing device will have the design safety factor required by NUREG-0612.

5. Lining devices that are not specially designed will be installed and used in accordance with the guidelines of ANSI B30.91971, " Slings." For heavy loads which have not been analyzed for the effects of a load drop, either dual or redundant slings or lining devices will be used, or the load used in selecting the sling will be twice the load specified in Section 5.1.l(5) of NUREG 0612.
6. Interfacing lin points will meet the design aafety factors as specified in NUREG-0612, l Section 5.1.6.
7. The crane will be inspected, tested and maintained in accordance with Chapter 2-2 of ANSI B30.2 1976 and the manufacturers recommendations, with the exception that tests and inspections will be performed prior to use where it is not practical to meet the frequencies of ANSI B30.2 for periodic inspection and test, or where frequency of crane use is less than the specified inspection and test frequency, i

lacIcased Load Capacity and Additional Loads The increase in the maximum load (to 80 tons) allowed over the SFP is justified in that the cask handling crane will be upgraded as a single failure proof crane for this doign load. The 3 allowance for the new components, added to Defueled Technical Specification 3.7. to travel over the SFP will be administratively controlled, transported with a single-failure proof crane, and prevented from traveling over the stored fuel assemblies in the SFP storage racks by the rask handling crane travel limit switch. All lining devices will be designed single-fai*ure-proof or will have an increased margin of safety as specified in NUI'.EG-0612.

The cask hatch cover and the. cask components and asweinted lining devices will travel over the fuel assemblics and GTCC waste placed in the shipping and'or transfer cask, llowever, the single failure-proof design, the rigging requirements, and the administrative controls provide a level of defense in-depth that minimizes the potential for a load drop. As such, a drop of the cask hatch cover or the cask components and associated lining devices is not a credibl* event.

Accident Assessment The fuel handling system will be used to transfer the fuel assemblics, one at a time, into the shipping and/or transfer cask. A maximum of 36 fuel assemblies will be loaded into each cask.

Dropping fuel assembly over the shipping and/or transfer cask is similar to a dropping a fbel assembly over the storage racks. The consequences of this type of fuel assembly drop is bounded

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,a, United States Nuclear Regulatory Commission September 5,1997 Page 11 by the design bases fuel handling event analysis discussed in the YNPS FSAR. The design bases fuel handling event assumes that a fuel assembly is dropped, strikes the floor, rotates toward the horizontal, and strikes a sharp object in the fuel assembly's most vulnerable area. The radiological analysis conservatively assumed that all of the gap activity in the damaged fuel assembly is released according to NRC Regulatory Guide 1.25, " Assumptions Used for Evaluating the Potential Consequences of a Fuelllandling Accident in Fuel llandling and Storage Facility for Boiling and Pressurized Water Reactors." The Exclusion Area Boundary doses which result from this postulated event are significantly less than the EPA Protective Action Guidelines.

Shkiding to Minimize Personnel Exnosure The substitution of the cask shielding for the minimum 5 feet of water over the fuel assemblics, when the fuel is being transported in the shipping and/or transfer cask, provides for the removal of the cask (and the fuel assemblics it contains) from the SFP. The shielding provided by the shipping and/or transfer cask systems will ensure that the exposure to personnel during movement of the shipping and/or transfer cask will be maintained ALARA.

Bulletin 96 02 i

YAEC has reviewed NRC Bullet n 96-02, " Movement of Heavy Loads Over Spent Fuel, Over Fuel in the Reactor Core, or Over Safety Related Equipment," dated April 11,1996. YAEC was not required to respond to the Bulletin because YNPS is not an operating plant and no longer has any operational safe shutdown systems. However, this submittal is consistent with the intent of Required Response Number (4), in that it identifies and proposes changes to the Technical Specifications that are required to allow the handling of heavy loads over fuel assemblies in the SFP. For the existing heavy loads permitted over the SFP, YAEC previously performed specific or bounding analyses which justified that these loads can be transported safely over the SFP and over the irradiated fuel (for those permitted by the Technical Specifications). YAEC is ensuring that its procedures for the control of heavy loads over the SFP are maintained in accordance with the existing regulatory guidelines.

For the shipping and/or transfer cask, the cask set-down pad, the cask hatch cover, the cask components and associated lifling devices, the single-failure-proof crane design provides assurance that these components can be moved safely. The single failure-proof cianc design precludes any credible single failure from preventing the crane to meet its design basis. Also, these heavy loads are prohibited (by operational and administrative controls, and, where specified in the Technical Specifications, limit switch) from movement over fuel assemblies in the SFP storage racks.

The only new loads allowed over spent fuel assemblies in the pool are the cask hatch cover and the cask components and associated lifling devices. This only occurs when placing the cask

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! - components on the shipping and/or transfer cask or when installing / removing the cask hatch cover aAer the fuel assemblies have been loaded into the cask. These loads will be handled by the

! single failure proof crane with dual rigging and dual lining devices or with devices with twice the i

! safety factor as required by NUREG-0612. Although a drop of the casic hatch cover or the cask )

1 components and associated liAing devices is not considered a credible event, administrative controls will be in place to ensure proper rigging and to minimize the time these loads are over the

! fuel assemblies. This is consistent with the intent ofNUREG 0612 and Bulletin 96 02.

SIGNIFICANT HAZARDS CONSIDERATION  :

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The changes described herein provide for an alternate method of providing protection of the spent ,

fuel and spent fuel pit (SFP) from heavy loads that must be transported over the SFP. The '

I method chosen, that is, providing a single-failure proof overhead crane, is considered an ,

t_ acceptable method as stated in Regulatory Guide 1.13," Spent Fuel Storage Facility Design i

Basis,"_ and NUREG-0612, " Control of Heavy Loads at Nuclear Power Plants " The Defbeled Technical Specification 3.1.2 requirement for five (5) feet of water above the top of the fuel L assemblies for fuel traveling in the SFP is provided for personnel protection (ALARA). This -

[ protection is provided by the shielding afforded by the shipping and/or transfer cask system. The

cask handling crane will comply with the single-failure-proof crane design requirements of j NUREG 0554, " Single Failure-Proof Cranes for Nuclear Power Plants," and meet the criteria j specified in NUREG-0612. In addition, design controls and administrative controls will be L - maintained to prevent handling of the shipping and/or transfer cask over spent fuel in the SFP. As
such, these changes will not

, 1. Involve a significant increase in the probability or consequence of an accident previously evaluated. NUREG-0612, Section 5, provides direction for providing an adequate level of '  :

defense-in-depth for handling of heavy loads near spent fuel and safe shutdown systems.

L The single failure-proof overhead crane design is presented as an acceptable method of

providing the proper margin of safety for handling of heavy loads. By upgrading the cask ,

l handling crane to a singlo-failure proof design and meeting the requirements presented in i Sections 5.1.1 and 5.1.6 of NUREG 0612 (for safe load path, procedures, crane operator training and qualification, special lifting devices, liAing devices that sre not specially ' i

[ designed, and crane inspection, wting, and maintenance) a sufficient level of defense in-l - depth is provided to ensure that a load drop is not a credible event. As such, there is no

~l Increase in the probability or consequence of an accident previously evaluated as a result of the heavy load changes. A fuel handling incident is a currently analyzed event; dropping of a fuel assembly over the spent fuel within the transfer cask is similar to 1

dropping of a fuel usembly ovu spent fuel in the SFP. The design basis fuel handling event analysis bounds these events, so there is no increase in the probability or

, consequence of an accident previously evaluated.

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United States Nuclear Regulatory Commission September 5,1997 Page 13

2. Create the possibility of a new or different kind of accident from any accident previously evaluated. The defense in-depth philosophy provided by the single failure proof crane load handling system design, and compliance with the requirements specified in Sections 5.1.1 and 5.1.6 ofNUREG 0612 provide assurance that for a credible single failure of the crane load handling system, the system will still be able to perform its safer, function.

This provides assurance that a load drop accident is not a credible event. As such, no new or different kind of accident will be created from any accident previously evaluated.

3. Involve a significant reduction in a margin of safety. The proposed changes implement the guidelines of NUREG-0612 and Regulatory Guide 1.13. YAEC is implementing an acceptable alternate method of ensuring the safe handling of heavy loads over the SFP.

This method provides a defense in depth approach for handling of heavy loads over the SFP and maintains the margin of safety consistent with that of the current requirements.

Further protection is provided by the prohibition of these additional heavy loads from travel over the spent fuel assemblies in the SFP racks. The use of a single-failure proof crane and associated lifting devices provide an increased margin of safety that ensure that a load drop event is not credible and is considered an adequate alternate for the additional area added to the safe load path. The use of a limit switch to prevent movement of the prohibited cask handling crane loads from movement beyond the safe load path, provides an additional margin of safety, that was previously provided by the steel framing at the southern edge of the SFP superstructure roof opening. The single-failure-proof crane and defense-in-depth design ensure that a load drop is not a credible event, assuring that the .

margin of safety is not reduced.

Based on the above considerations, it is concluded that there is reasonable assurance that the operation of Yankee Nuclear Power Station consistent with the proposed changes will not endanger the health r.nd safety of the public.

This proposed change has been reviewed by the Plant Operations Review Committee and the Nuclear Safety Audit and Review Committee, i

SC11EDUII OF CilANGE These changes to the YNPS Defueled Technical Specifications will become effective upon NRC approval of these changes and YAEC acceptance of the crane modificat i ons. This will provide assurance that the modifications are completed and tested, and that the administrative controls are in place to fully implement the revised Technical Specification. The crane design has been initiated with fabrication scheduled to follow immediately thereafter. The crane modifications are scheduled to be completed by the third quarter of 1998 YAEC requests NRC approval in support of meeting this schedule (with implementation contingent on completion of the crane upgrade modifications),

i

v United States Nuclear Regulatory Commission September 5,1997 '

Page 14 We trust you will fmd this submittal satisfactory; however, should you desire additional information, please contact Jane Grant or me.

l Very truly yours, l

l YANKEE ATOMIC ELECTRIC COMPANY Stephen P. Schultr, Sc. D.

{'

Vice President gar Attachments c: Mr. John White, USNRC Region I COMMONWEALTil OF MASSACilUSETTS WORCESTER COUNTY Then personally appeared before me, Stephen P. Schultz, Sc. D who, being duly sworn did state that he la Vice President of Yankee Atomic Electric Company, that he is duly authorized to execute and file the foregoing document in the name and on the behalf of Yankee Atomic Electric Company, and that the statements therein are true to the best ofhis knowledge and belief.

Kathryn Gates / Notary Public My Commission Expires January 1,2004

4

, ATTACIIMENT A EDERER NUCLEAR SAFETY-RELATED X-SAM CRANE l

SAFETY SYSTEM PROTECTION The discussion below provides a summary of the types of safety systems used in the X SAM l Crane design for protection against _ equipment malftmetions and operator errors. To provide this protection the X Sam Crane utilizes the following three types of safety systems:

e l The conventional hoist safety systems; i The 11oist's Integrated Protective System (filPS); and I

e The Balanced Dual Reeving System The conventional hoist safety systems include upper and lower travel limits, overload sensing devices, hoist control protective features, and a holding brake on the high speed shafting. By preventing the incidents that cause overloads from occurring, these systems provide the X SAM Cranes with the first line of defense against overloads. The conventional holding brake on the high speed portion of the drive train holds the load during normal operations.11oisting and load control is provided by hoist duty electric motors and controls.

The lioist's Integrated Protective System provides the second line of defense for the X-SAM Cranes The lioist's Integrated Protective System prevents overload of hoist components even if incidents occur that would have caused overloads in conventional hoists. The lioist's Integrated Protective System also protects against other types ofincidents, such as improper wire rope spooling. In addition, the lioist's Integrated Protection System provides an independent, emergency braking method for stopping and holding the load in the event of a single failure in the conventional emergency stopping method.

The Holst's Integrated Protective System includes an Energy Absorbing Torque Limiter (EATL) in the drive train, a special Emergency Drum Brake System that acts on the wire rope drum, and a Failure Detection System. If a drive train discontinuity or component failure occurs, the Failure Detection System will actuate the Emergency Drum Brake System, stopping the wire rope drum.

The Energy Absorbing Torque Limiter allows the hoist to safely withstand two blocking, overloading, or load hangup while still retaining the load (even if the drive motor is not de-energized), The Energy Absorbing Torque Limiter not only controls the loads, but the hoist's components are also protected from being over strest.ed as a result of these incidents. The Energy Absorbing Torque Limiter provides this protection by directly converting the hoist's high speed kinetic energy _to heat during an overloading incident.

Another safety feature of the X SAM crane is the emergency lowering capability that is provided

- by the Emergency Drum Brake System. The Emergency Drum Brake System allows lowering of the design rated load continuously from the maximum hook height without exceeding the temperature limits of the brakes. This system negates the necessity to frequently stop, to allow

the brakes to cool, when lowering the load By allowing the load to be lowered continuously i without exceeding the temperature limits of the brakes, this system provides the ability to place the load in a secure position in minimal time.

The primary f v; tion of the Failure Detection Systems is to detect a loss of mechanical continuity in the hoist machinery and, when necessary, detect actuation of the Energy Absorbing Torque Limiter. The Failure Detection System consists of detectors to sense improper rope spooling, reeving continuity, and drum overspeed. An error signal in any of these parameters initiates actuation of the Failure Detection System and results in shutdown of the crane hoist machinery and subsequent setting of the Emeigency Drum Drake System.

The Balanced Dual Reeving System protects against both loss ofload and load sway in the event of a single cable failure. To achieve this capability, the system is balanced in a unique method that protects the wire rope from being cut or crushed if the upper limit switches fail. This feature permits the X SAM crane to utilize the inherent energy absorbing capability of the wire rope to withstand two-blockings. The Ilydraulic Load Equalization System (a subsystem of the Balanced Dual Reeving System) limits the load motion following a cable failure. In addition, the Failure Detection System will activate in the event of a cable failure.

This is a summary of the safety features provided in the Ederer X SAM Crane design. Further details are provided in the General Licensing Topical Report (Reference (c)) concerning the Ederer X-SAM Crane design.

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