ML20126K031

Rev 6 to Defueling Water Cleanup Sys

ML20126K031
Person / Time
Site:	Three Mile Island
Issue date:	06/03/1985
From:	Boldt G, Smith E GENERAL PUBLIC UTILITIES CORP.
To:
Shared Package
ML20126K020	List: ML20126K016 ML20126K031
References
15737-2-G03-106, 15737-2-G03-106-R06, 15737-2-G3-106, 15737-2-G3-106-R6, NUDOCS 8506190148
Download: ML20126K031 (5)

Text

.

Nuclear T E R is737-2-co3-206 nev, 6 ISSUE DATE G ITS O NSR O NITS TMI-2 DIVISION TECHNICAL EVALUATION REPORT FOR Defueling Water Cleanup System COG ENG 9/880/M DATE vNf'/

RTR b Cd DATE o///W COG ENG MGR. 6/42p-RtA- DATE "' +

p6 6/A/3s Revised and Reissued for Use ff)Z # Ed C CAO---

()d5 '/8%- Issued For Use j))f, ~}V f f'y p4 +/it)/g Issued For Use /yyy gpg rg g 3 'bo/g Issued For Use /)1/- ) Fg GE_.

'4de/d6 Issued For Use AJI M - MS A

. 2

'2/7/M 8 )Z D M W

$ 1 0 'V'/m '

1nnued Far 11ne Issued For Use /M M 6M C o oce , neveone e, c-eciso d*4*o. ."&t11%_

E6ei. A//A 0506190140 850613 0 DR ADOCK 050 DOCUMENT PAGE 1 op 19_,,

tPO 110131 cree i

4 NO.

!k!LICIbENEUI 15737-2-G03-106 Title PAGE OF Technical Evaluation Report for Defueling Water Cleanup System 2 19 Rev.

SUMMARY

OF CHANGE O Initial issue November 1, 1984 1 Revised to incorporate system design changes and comments on Revision 0 2 Revised to incorporate comments on Revision 1 3 Revised to incorporate comments on Revision 2 4 Revised to reflect addition of relief valves at the outlets of the defueling filter canisters, deletion of fuel pool cleanup system boronometer and correction of minor typographical errors 5 Revised to correct and clarify description of low level alarm setpoints for fuel transfer canal 6 Revised to reflect the potential for operation of portions of the DWC system prior to the system being fully operational and to incorporate minor editorial changes EPQ 4M16 11144

15737-2-G03-106 1.0 Introduction 1.1 General The defueling water cleanup (DWC) system is designed to remove radioactive ions and particulate matter from the fuel transfer canal, spent fuel pool "A" and the reactor vessel. The majority of the particulate matter is removed by processing the water through nominal 0.5 micron rated sintered metal filters. The low micron rating of the filters will assure very low turbidity as well as reducing the particulate activity in the water.

Removal of the radioactive ions (i.e., soluble fission products) will be performed by processing a portion of the filter output through '

- 4 x 4 liners (similar to those in use for EPICOR 11) containing Zeolite, or the submerged domineralizer system (SDS).

The installation and operation of the DWC system will occur sequentially such that portions of the system may be operated prior to completion of the entire system. In addition, partial system operation may require temporary interconnection (s) with other plant 6 systems which are not specifically described in this Technical Evaluation Report. Any such temporary modes of DWC system operation l will be implemented in accordance with the safety criteria for the complete DWC system and will be bounded by the safety analyses described herein.

1.2 Scope The scope of this document includes the operation of the DWC system, the components of the DWC system and its interfaces to existing systems and components. This technical evaluation report (TER) is applicable only during the recovery mode as the DWC system is a temporary system required to support recovery operations and will be  ;

removed or reevaluated prior to plant restart. Evaluation of safety concerne related to the filter canisters is not within the scope of this TER and will be addressed in Reference 8. Licensing of the ion exchangers for offsite shipments is outside the scope of this TER.

2.0 System Description

2.1 General The DWC system is designed to process water from the reactor vessel, .

spent fuel pool, and fuel transfer canal. The system's major l functions are given below.  ;

a) The DWC system filters the water contained in the reactor I vessel, the apont fuel pool, and the fuel transfer canal to  !

remove suspended solids above a nominal 0.5 mict'on rating. This is done to maintain the clarity of the water to a 1 NTU (nephalometric turbidity unit) rating. l b) The DWC system removes soluble fission products from the reactor vessel, the spent fuel pool, and the fuel transfer canal (FTC) by domineralisation of the water. This is done to reduce the ,

l dose contribution from the water.

Rev. 6 l 0058Y

15737-2-003-106 3.2 Postulated Systen Failures 3.2.1 Reactor Vessel Cleanup System 3.2.1.1 Loss of Power A loss of power to the entire system would simply shut the system down. A loss of power to the won pumps with an additional failure which results in I simultaneous loss of level control in the ion exchangers would result in a flow mismatch. In this case, the system would be automaticany shut down until power is restored. Imse of power to individual components would place that component in its safe mode. An air operated valve, for example, would fail 6 to a position that ensures no damage to other components.

Imss of power to the control panel would cause the loss of an information and fail au control and solenoid operated valves. The system would be shutdown until power is restored.

3.2.1.2 Ioss of Inst watation/ Instrument Air Loss of a single instrument channel will result in the loss of indication for that channel and, for those channels that have control features a flow mismatch.

This flow mismatch will result in an automatic shutdown of the affected portion of the system.

Ioss of the internals indexing fixture (IIF) level indication system (bubbler) win result in an erroneous level indication which will be noted when compared with a redundant level indication system.

Since this system has no control features, no adverse system conditions will result.

loss of instrument air win take the individual components to their fail safe position. Flow mismatches induced by loss of air will result in automatic trips. Imse of air to the IIF level monitoring system will initiate a low air supply pressure alare.

3.2.1.3 Filter Media Rupture A failure of the filter media in the canister could potentially release fuel fines to the ion exchange portion of the system. A post filter is located downstream of both filter trains in the line to the Rev. 6 0058Y

. 15737-2-003-106 inches below the water level. Also, isolation valves will be provided in the Westinghouse supplied piping which could be cced to manually terminate the  ;

siphoning. Therefore, a maximum of approximately 3000 I as11ons of reactor vessel water would spill into the i fuel transfer canal following a hose rupture. l Approximately half of this water would be contained in I the New Fuel Pit. I The recovery from these events would be accomplished by isolating the ruptured section and replacing the ruptured hose / pipe.

3.2.2 Fuel Transfer Canal / Spent Fuel Pool Cleanup System 3.2.2.1 Loss of Power A loss of power to any portion of the system would shut that portion of the system down. Loss of power to individual components would place that component in its safe mode. An air operated valve, for example

• 6 would fail to a position that ensures no damage to other components.

3.2.2.2 Ioss of Instrumentation / Instrument Air Imse of a single instrument channel will result in the loss of indication for that channel and, for those channels that have control features a flow missatch.

This flow mismatch will result in an automatic shutdown of the affected portion of the system.

Imse of either the spent fuel pool or FTC level monitoring system will be noted when compared with the other. The readings should normally be the same since both water bodies are in communication via the fuel transfer tubes. Neither system has control features.

Imse of instrument air will take the individual components to their fail safe position. Flow mismatches induced by loss of air will result in automatic trips. Imse of air to the IIF level monitoring system (bubbler) will initiate a low air supply pressure alare.

3.2.2.3 Filter Media Rupture A failure of the filter media in the canister could potentially release fuel fines to the ion enchange portion of the systes. Flow may be routed to DWC los exchanger K-2 or to the SDS both of which have filters upstresa to trap migrating fuel fines. Ion enchanger K-2 has a cartridge type filter in a critically safe Rev. 6 0054Y