ML19309D753
| ML19309D753 | |
| Person / Time | |
|---|---|
| Site: | Crane  |
| Issue date: | 04/02/1980 |
| From: | Herbein J METROPOLITAN EDISON CO. |
| To: | Reid R Office of Nuclear Reactor Regulation |
| References | |
| TLL-154, NUDOCS 8004110395 | |
| Download: ML19309D753 (1) | |
Text
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Metropolitan Edison Company Post Ofice Box 480 e
Middletown, Pennsylvania 17057 717 9444041 Wnter's Direct Dial Number April 2, 1980 TLL 154 Director of Nuclear Reactor Regulations Attn:
R. W. Reid, Chief Operating Reactors Branch No. 4 U. S. Nuclear Regulatory Commission Washington, D. C.
20555
Dear Sir:
Three Mile Island Nuclear Station, Unit 1 (TMI-1)
Operating License No. DPR-50 Docke t No. 50-289 Reactor Building Spray System In response to your letter of March 7,1980, we have evaluated the TMI-1 Reactor Building Spray System (RBSS). We have determined that by eliminating the sodium thiosulf ate tank and adjusting the sodium hydroxide tank concen-tration and level, the system can maintain a spray pH between 8.5 and 11 0 under all single failure conditions except failure of BS-V2A/B. If BS-V2A/B fails to open, the spray pH exceeds 11.0.
The pH limits of 8.5 and 11.0 are necessary to prevent corrosion ef fects yet remove the maximum amount of iodine.
We are currently investigating ways to overcome the above single f ailure condition. It appears that a close coupling of the Sodium Hydroxide Tank and Borated Water Storage Tank will eliminate the high spray pH for this single f ailure. We are now determining whether or not close enough coupling of these tanks is possible given the physical plant arrangement. Assuming that an adequate close coupling can be achieved, studies would be performed to specify the acceptable tank concentration and ranges. A Technical Speci-fication Change including the studies will then be submitted to reflect the new tank limits, and delete the sodium thiosulf ate tank from the specifications.
This change request will also address of fsite dose concentrations for the modified sys tem.
i We anticipate that our technical specification change request will be forwarded for your approval by September 1,1980.
l Sincerely, J. G. Herbein D
g Vice President - Nuclear Operations JGH:dw 80oil J Ogg cc:
J. T. Collins H. Silver la Metropohtan Ecson Company is a Member of the General Pubhc Utsties System