Morning Report for Macrh 21, 2000

                       Headquarters Daily Report

                         MARCH 21, 2000

                    REPORT             NEGATIVE            NO INPUT
                    ATTACHED           INPUT RECEIVED      RECEIVED

REGION I            X
REGION II                              X
REGION III                             X
REGION IV                              X

MR Number: H-00-0019

                           NRR DAILY REPORT ITEM
                           GENERIC COMMUNICATIONS

Subject: ISSUANCE OF RIS 2000-06 dated March 20, 2000

NRC Regulatory Issue Summary 2000-06--Consolidated Line Item Improvement
Process for Adopting Standard Technical Specifications Changes for Power
Reactors, dated March 20, 2000

The U.S. Nuclear Regulatory Commission has issued this regulatory issue
summary to inform the addressees of the opportunity to participate as
applicants in the consolidated line item improvement process for
Technical Specifications amendments.

Technical contacts: Tilda Y. Liu, NRR           William D. Reckley, NRR
                    301-415-1315                301-415-1323
                    E-mail:         E-mail:

HEADQUARTERS      MORNING REPORT     PAGE  2          MARCH 21, 2000

Licensee/Facility:                     Notification:

                                       MR Number: H-00-0020
General Electric Nuclear Energy        Date: 03/21/00
San Jose,California

Subject: Minimum Control Voltage Test for GE Type AK/AKR
         Circuit Breakers


The NRC has learned that General Electric Nuclear Energy (GE NE) has
issued a 10 CFR Part 21 notification (under 21.21(b)) to licensees and
affected purchasers concerning a possible inconsistency in testing
safety-related 480-Vac circuit breakers at the minimum nameplate control
voltage rating during breaker maintenance and overhauls performed by GE
Apparatus Service Division switchgear service shops under the QA
supervision of GE NE.  Potentially affected breakers include
electrically-operated types AK-15, AK-25, and AKR-30S. The manufacturer's
original nameplate rating specified a minimum closing voltage of 90 Vdc
for 125 Vdc applications and 180 Vdc for 250 Vdc applications, in
accordance with the applicable industry standard (ANSI/IEEE C37.16).

In 1980, the standard was revised, increasing the specified minimum
closing voltage to 100 Vdc for 125-Vdc applications and 200 Vdc for
250-Vdc applications. The current GE test procedures (approved for use on
safety-related breakers by GE NE) were originally developed in the 1980's
and followed the 1980 edition of the standard. As a result, GE facilities
have reportedly been testing serviced breakers of the types in question
with the 90-V (or 180-V) nameplate rating at the higher minimum closing
voltage of 100 Vdc (or 200 Vdc) as applicable.

This issue is not a problem for licensees whose lowest design basis
control voltage at the breaker is 100 Vdc (200 Vdc) or greater; nor is it
a problem for licensees who perform their own test at or below their
expected minimum control voltage (as recommended by the EPRI/NMAC Circuit
Breaker Users Groups guidance documents). In determining the appropriate
control voltage at which to test breakers, some licensees also consider
applying some margin to account for error in the minimum voltage
calculations and in measuring the test voltage. However, GE NE recommends
that licensees with expected minimum voltage below 100 Vdc (200 Vdc) who
have relied on the GE testing to show that the breakers will close
electrically at the plant's minimum voltage should determine whether they
are impacted by this reported discrepancy.

NRC staff discussed this issue with GE NE and learned that GE NE hosted a
conference call with interested utilities on 2/29/00. In addition, NRC
staff has been in contact with the EPRI/NMAC GE Circuit Breaker Users
Group to discuss this issue. GE NE reports it has revised its test
procedures to test breakers at the nameplate minimum voltage. However, GE
NE also reports that of the breakers tested by GE facilities since this
revision to the GE NE-approved procedures, fewer than 5 percent have
failed to close at 90 Vdc, and of those, all closed successfully at no
more than 93 Vdc. GE NE told the staff that only the test requirements
used by GE NE changed after 1980, not the actual closing solenoid design.
The closing solenoid design used in the potentially affected breakers has
remained the same since the original design.
HEADQUARTERS      MORNING REPORT     PAGE  3          MARCH 21, 2000
MR Number: H-00-0020 (cont.)


Dave Skeen, NRR         Kamal Naidu, NRR        Stephen Alexander, NRR
301-415-1174            301-415-2995            301-415-2980      
REGION I  MORNING REPORT     PAGE  3          MARCH 21, 2000

Licensee/Facility:                     Notification:

Connecticut Yankee Atomic Power Co.    MR Number: 1-00-0004
Haddam Neck 1                          Date: 03/20/00
Dockets: 50-213



On March 16, 2000, approximately one hundred gallons of reactor cavity
water overflowed through the cavity water filtration vent drum onto the
charging floor inside containment and down to the mid and lower
elevations of two loop areas.  The system was shut down and all cutting
in the reactor cavity was suspended.  The vent drum was associated with a
500 hundred gallon back wash tank that apparently overfilled.  System
evaluations, modifications and area decontamination occurred over the

On March 20, 2000, the licensee resumed filtration operations after
modifications to prevent tank overflow and remediation of the charging
floor.  Although the event could not be recreated, two system
modifications (a vent pipe for drainage directly to the reactor cavity
and a back wash tank level trip) were made.  Human error was considered
highly unlikely since no workers were observed at the computer station to
open the valves.

An NRC inspector has been onsite since March 19, 2000 to observe the
licensee's follow-up to this event as part of a routine inspection as the
licensee continues its decommissioning activities.  There were no
personnel contaminations, no internal doses, and no radioactive releases
to the environment as a result of this event and subsequent remediation

Regional Action:

Regional Inspection

Contact:  S. Shaffer                 (610)337-5256
          R. Bellamy                 (610)337-5200

Page Last Reviewed/Updated Wednesday, March 24, 2021