ML20003E412
| ML20003E412 | |
| Person / Time | |
|---|---|
| Site: | Yankee Rowe |
| Issue date: | 03/31/1981 |
| From: | Kay J YANKEE ATOMIC ELECTRIC CO. |
| To: | Eisenhut D Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-2.B.1, TASK-2.E.4.2, TASK-TM FYR-81-50, NUDOCS 8104030390 | |
| Download: ML20003E412 (3) | |
Text
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YANKEE ATOMIC ELECTRIC COMPANY
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Q,f 1671 Worcester Road, Framingham, Massachusetts 01701 3
YANKEE' s
FYR 81-50 March 31, 1981 United Sta tes Nuclear Regulatory Commiss ion Wash ington, D. C.
20555 A t ten tion :
Mr. Darrell G. Eisenhut, Director Division of Licensing
Reference:
(a) License No. DPR-3 (Docket No. 50-29)
(b) USNRC Letter, D. G. Eisenhut to all Licensees of Operating Plants, dated October 31, 1980 (NUREG-0737)
(c) YAEC Letter to USNRC, dated December 15, 1980 (WYR 80-136)
Subject:
TMI Action Plan Items II.E.1.2 and II.E.4.2
Dear Sir:
This letter transmits additiona' information required by NUREG-0737, Reference (b).
Tne information is contained in the Enclosure and is provided at this time as dis cussed in Re ference (c).
The information discusses the following TMI Action Plan items:
Item II.E.1.2 - Auxiliary Feedwater System Flow Indication Item II.E.4.2 - Containment Isolation Dependability We trus t you will find this information satis factory, however, if you have any questions please contact as.
Very truly yours, YANKEE ATOMIC ELECTRIC COMPANY J. A. Kay Senior Engineer - Licensing BLD/ dis Enclosure 81040so390 f
p Page 1 of 2 Fnclosure Yankee Atomic Electric Company Section II.E.1.2 Part 2 Auxiliary Feedwater System Flowrate Indication Clarification Subsection No. 2:
(a)
One Controlotron Ultrasonic Flowmeter for the measurement of emergency feedwater flow rate, Model 241-1 1/2 CS, 80-A was attached to each emergency boiler feedwater line upstream of the connection to the main feedwater lines.
Steam generator level indicators are used as a second indication of plant conditions.
(b)(i)
The fully implemented flow indication system is environmentally qualified for the area in which it is used. The units are designated suitable for use in a -20 F to +110 F environTen t.
(ii)
The flow indication system is powered from the Vital Bus, a highly reliable battery backed power source.
(iii) The implemented flow indicating systems have provisions for periodic tes ting and local fault alarm signaling.
(iv)
The implementation and purchasing of this equipment was part of the plant Quality Assurance Program.
(v)
A continuous display of flow rate is available on the Main Con.rol Board (MCB) as well as a local indication.
The displays which were added to the main control board were located with consideration for the operator's best perception and for minimal ambiguity.
(a) The flow indication derived by this system is located in a section of the control board where the information can best be effectively displayed during both normal and abnormal conditions.
(b) The specifics of this change has been incorporatad into plant emergency procedures.
(c) The Plant Operators were instructed on this ins trumen ta tion.
Documen ta tion :
Supporting information including system design description, logic diagrams, electrical schematics, piping and instrument diagnosis test procedures and technical specifications are available for NRC review at the Yankee Rowe site.
f E.
aI Page 2 of 2 Section II.E.4.2 Containment Isolation Dependability i
Position No. 5 The Technical Specifications for the CIS trip setpoint at Yankee Rowe is 5.0 psig. The actual setpoint for calibration is lower at 4.5 +.3 psig to insure that the 5.0 psig specification is met at all times. Yankee Rowe, unlike mos t plants, does not.have a higher pressure which isolates essential valves. At i
- Yankee Rowe all containment isolation valves, both essential and non-essential, isolate at the CIS setpoint of f 5.0 psig.
In addition,. the Technical Specifications of Section 3.6.1.4 and 3.6.1.7 limit I
the operating normal coatainment pressure to between 0.75 and 3.0 psia. This 1
is to accommodate the continuous leak monitoring system utilized to verify containment integrity during plant operation. Therefore, the range between o
the normal operating pressure and the trip setpoint allowing for downward drif t of the CIS pressure ' switches is a very narrow band.
A tech spec lower than 5.0 psig would be unduly restrictive.
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