Part 21 Report - 1995-038

PRIORITY ATTENTION REQUIRED  MORNING REPORT - REGION I  JANUARY 31,
1995

Licensee/Facility:                     Notification:

Connecticut Yankee Atomic Power Co.    MR Number: 1-95-0014
Haddam Neck 1                          Date: 01/31/95
Hartford,Connecticut                   SRI E-Mail                         
Dockets: 50-213
PWR/W-4-LP                            

Subject: Inoperable Pressurizer Relief Valves                            
                                                                         
Reportable Event Number: N/A

Discussion:

While shutting down for a refueling outage, plant personnel performed a  
routine surveillance test on the pressurizer power operated relief valves
(PORVs) with the reactor operating in Mode 4 on January 29.  Both valves 
(RC- 568 & 570) failed the test in that they would not operate to the    
full open position, and did not operate within the time required by the  
IST program.  The PORVs are Copes-Vulcan model 080813 air operated       
valves.  This was the third test failure of both valves in about two     
years.  The licensee reported past failures as LER 94-05 (caused by      
excessive air leakage out of the air actuator due to improper assembly of
the diaphragm/cover); and LER 93-07 (caused by inadequate sealing of the 
diaphragm assembly and corrosion failure of the regulator supplying air  
to the valves).                                                          
                                                                         
At Haddam Neck, the PORVS do not perform the LTOP function (different    
valves are used), but the valves are required to be operable by Technical
Specification 3.4.4 and are (i) designed to minimize the challenges to   
the pressurizer code safety valves for overpressure events; and (ii)     
credited for use in the EOP network as the feed and bleed path for loss  
of feedwater and steam generator tube rupture events.  The licensee's    
preliminary investigation noted that both valves stroke smoothly and do  
not appear to have the excessive external leakage problems noted in past 
LERs.  Licensee investigation is in progress and will continue during the
performance of the pressure drop test for the PORV air supply header.    

Regional Action:

Routine resident followup.                                               

Contact:  William Raymond            (203)267-2571
          Larry Nicholson            (610)337-5128