IR 05000315/1997201
| ML17334B663 | |
| Person / Time | |
|---|---|
| Site: | Cook  |
| Issue date: | 12/10/1997 |
| From: | NRC (Affiliation Not Assigned) |
| To: | |
| Shared Package | |
| ML17334B662 | List: |
| References | |
| 50-315-97-201, 50-316-97-201, NUDOCS 9712120339 | |
| Download: ML17334B663 (4) | |
Text
Addendum to Inspection Report 50-315/316/97-201 The seven examples listed below that are contained in Section E1.5.2.B of Inspection Report 50-315/316/97-201 and were inadvertently omitted from the Appendix A open items list. These seven examples have been designated as URls 50-315/316/97-201-28 through 34.
The team determined that the licensee had operated the plant above the maximum UHS temperature limitwithout performing a 10 CFR 50.59 evaluation, which also potentially created a USQ with regard to a reduction of safety margin as defined in the TS Bases for the control room emergency ventilation temperature limitof 95'F. (Report Section E1.2.1.2E(1))
URI 50-315/316/97-201-28 (2)
The licensee's 10 CFR 50.59 evaluation, dated March 11, 1996 and March 20, 1996, respectively, that was performed to evaluate the consequences of the 1996 Unit 2 full-core oNoad, failed to recognize the significance that the CCW heat exchanger could not perform its function under the design basis assumptions that were stated in the UFSAR and other licensing basis documentation.
In addition, the licensee also failed to address UFSAR Section 9.4, regarding the criteria for SFP cooling time-to-boil events and subsequently failed to identify that the conclusions reached in the evaluation would have potentially reduced the time-to-boiling in the SFP, given the assumptions stated in the SFP loading calculation and in the UFSAR: Reduction in the time-to-boiling criteria potentially impacts the probability of occurrence or the consequences of an accident or malfunction previously evaluated in the safety analysis report and is an apparent USQ.
(Report Section E1.2.1.2C 1)
Additionally, this safety evaluation also failed to identify that a dual CCW/ESW train outage with one unit in refueling and the other unit at power, was contrary to the UFSAR assumptions and placed the plant in an unanalyzed condition and outside of the design bases.
This condition also potentially increased the probability of occurrence or the consequences of an accident or malfunction previously evaluated in the safety analysis report, creating the potential for a USQ. (Report Section E1.2.1.2D)
URI 50-315/316/97-201-29 (3)
The 10 CFR 50.59 safety evaluation that was performed by the licensee for Revision 2, dated June 1992, to EOP OHP 4023.ES-1.3 was not effective in identifying that the revision was creating a single failure vulnerability that could render one RHR pump and both safety-related trains of Sl and CC pumps inoperable.
Subsequent procedural revisions (Revisions 3 8 4, dated January 1996, and January 1997, respectively) failed to identify the single failure vulnerability. (Report Section E1.1.1.2D)
URI 5015/316/97-201-30 (4)
In 1996 (Unit 2) and 1997 (Unit 1), the licensee filled in the containment recirculation sump roof vent holes without performing a 10 CFR 50.59 evaluation.
The licensee stated that the holes were sealed because they were not indicated on any plant design drawings and because the they could not locate any design requirement for consideration of the vent holes.
(Report Section E1.1.1.2E 1) URI 50-315/316/97-201-31 97i2i20339'7i2iO I m aOGCK aSOaOSiS
.PDR Enclosure
-2-(5)
Procedure 01/02-OHP 4021.016.003, "Operation of the Component Cooling Water System During Reactor Startup and Normal Operation," was revised to remove the statement, "allowing three hours at CCW temperatures. of 120'F." The licensee implemented the revision under the auspices of a non-intent procedural change, as allowed by TS 6.5.3.1.
However, the team determined that this revision constituted a change to the intent of the procedure, contrary to the conclusion reached by the licensee.
(Report Section E1.2.1.2C)
URl 5015/316/97-201-32 (6)
The licensee consistently operated the plant with less than the UFSAR-specified CCW flows through the RCP thermal barriers and without performing a 10 CFR 50.59 evaluation.
This issue is of concern because the CCW system has operated above the maximum design basis CCW temperature limitof95', and was allowed to operate at temperatures up to 120'F, without evaluating the impact on the RCP thermal barriers with the reduced CCW flows. (Report Section E1.2.1.2G) URl 50%15/316/97-201-33 (7)
The licensee identified that they have operated the plant without over pressure protection to the RHR system, contrary to the assumptions stated in UFSAR Chapter 9.3. This change to the design basis feature that provides over pressure protection to the RHR system was to defeat the interlocks associated with ICM-129 and IMO-128, RHR hot leg inlet isolation valves, when operating in Mode 4. However, the change was performed without performing a 10 CFR 50.59 evaluation.
(Report Section E1.5.2C 3) URl 50-315/316/97-201-34
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