Headquarters Daily report

                         JULY 13, 1994

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                    REPORT             NEGATIVE            NO INPUT
                    ATTACHED           INPUT RECEIVED      RECEIVED
HEADQUARTERS                           X                   
REGION I                               X                   
REGION II           X                                      
REGION III                             X                   
REGION IV                              X                   
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PRIORITY ATTENTION REQUIRED  MORNING REPORT - REGION II  JULY 13, 1994

Licensee/Facility:                     Notification:

Duke Power Co.                         MR Number: 2-94-0057
Mc Guire 1                             Date: 07/13/94
Cornelius,North Carolina                                                  
Dockets: 50-369
PWR/W-4-LP                            

Subject: DILUTION OF SPENT FUEL POOL                                     
                                                                         
Reportable Event Number: N/A

Discussion:

The licensee began working on an isolation valve for the Spent Fuel Pool 
transfer tube on Sunday, July 10, 1994. The transfer canal was drained so
that work could be performed on the valve. A demineralized water spray of
the transfer canal walls was initiated to reduce airborne contamination  
while the work was in progress. The demineralized water collected at the 
bottom of the canal was pumped into the spent fuel pool. No provision was
made to increase chemistry sampling frequency or to add boron to offset  
the dilution in the pool. As a result, the boron concentration, usually  
maintained between 2050 and 2100 ppm, dropped below the Technical        
Specification (TS) limit of 2000 ppm to 1958 ppm, according to the       
results of a sample collected in the afternoon of July 12, 1994. The     
licensee responded by adding 2000 pounds (11 barrels) of boron to the    
pool at 4:50 p.m. on July 12. A chemistry sample taken at 7:50 p.m. on   
July 12, indicated that boron concentration was returned to within TS    
limits. The licensee has taken action to better coordinate the draining  
of the canal of demineralized water during the remaining work on the     
isolation valve.                                                         

Regional Action:

Resident Inspectors and the Region are continuing to follow up on this   
event.                                                                   

Contact:  Rani Watkins               (404)331-5678