ML20024H945
| ML20024H945 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 08/19/1993 |
| From: | Greenman E NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Antony D NORTHERN STATES POWER CO. |
| Shared Package | |
| ML20024H946 | List: |
| References | |
| NUDOCS 9308310002 | |
| Download: ML20024H945 (4) | |
See also: IR 05000306/1993015
Text
_ _ - _ _ _ _ _ _ _ _ _ - - _ _ _
_ _ _ _ _ _ - - _ _ - - - - - - _ - - - - - _ - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - --
--
.
4
pf' Moo
UNITED STATES
[
fg
NUCLEAR REGULATORY COMMISstON
S
nEclou m
$
if
%
g
GL E N E LLYN, ILLINOIS 60037
- % . . . . . de
00S
7
T33
Docket No. 50-306
License No. DPR-60
Northern States Power Company
ATIN:
Mr. D. D. Antony
Vice President, Nuclear
Generation
414 Nicollet Mall
Minneapolis, MN 55401
Dear Mr. Antony:
SUBJECT: NRC INSPECTION REPORT 50-306/93015
This refers to the special safety inspection conducted by Messrs. M. L. Dapas
and R. L. Bywater of this office on July 19 through 30, 1993.
The inspection
focused on an event at your Prairie Island Nuclear Generating Plant on
July 19, 1993. Specifically. both trains of the safety-related ventilation
system for the Unit 2 emergency diesel generator building were simultaneously
removed from service for a period of about 15% hours.
The findings of our
inspection were discussed with Mr. M. D. Wadley and other members of your
staff on July 30, 1993.
Areas examined during the inspection are identified in the report.
Within
these areas, the inspection consisted of selective examinations of procedures
and representative records, interviews with personnel, and observation of
activities in progress.
Based on the results of this inspection, certain of your activities appeared
to be in violation of NRC requirements, as specified in the enclosed Notice of
Violation (Notice). This violation is of particular concern because it
involved operating in a condition prohibited by the Prairie Island Technical
Specifications (TS). Specifically. TS 3.7.B.6 and 3.7.B.1 provide limiting
conditions for operation with respect to 4160 Volt and 480 Volt safeguards
buses and EDGs. Allowed periods of inoperability and associated required
actions are specified in the IS for a single train of each of the above
systems.
The D5/D6 building HVAC system provides ventilation to the Unit 2
4160 Volt and 480 Volt safeguards bus rooms and the D5 and D6 EDG control
Your design report for the Station Bla Mout/ Electrical Safeguards
rooms.
Upgrade Project (which is part of the current licensing basis for Unit 2)
states that the 05/D6 HVAC system will provide for removal of electrical
equipment heat loads to maintain equipment within qualification limits and
operatii,9 limits during all plant operating conditions.
This design report
l
.I
9308310002 930819
L'
ADOCK 05000306
'
,
G
8 l
u
_ _ _ _ _ _ _ _ _ _ _ _ _ - - -
_
rr
-
.
.
Northern States Power Company
2
clearly establishes that the 05/D6 HVAC system is an essential s'upport system
for the electrical equipment contained in the rooms that this ventilaticn
system serves. Therefore, the cooling function of the D5/D6 HVAC systec is
required to ensure that Unit 2 safeguards electrical equipment is operable.
Consequently, securing both trains of the 05/D6 HVAC system on July 19, 1993,
placed both trains of Unit 2, 4160 Volt and 480 Volt safeguards buses, and the
D5 and D6 EDGs in an inoperable condition. Operation at power in this
condition is prohibited by the TS.
Licensee management _has the responsibility to provide its operators with the
tools they need to safely operate the plant. This violation was the result of
your failure.to provide operators with adequate guidance to implement the
l
definition of operability relative to essential support equipment. The NRC
i
expects you to provide training and/or guidance to the licensed operators as
,
to what constitutes an essential support system and which specific plant
I
systems / components are considered essential for ensuring the operability of
j
the parent system / component.
It was not until the NRC inspectors raisec~ a
i
concern regarding the HVAC system support function, that you provided guidance
o
as to which specific plant systems / components are considered essential for
!
ensuring the operability of the parent system / component.
This guidance was in
.;
the form of a Daily Order and was specific only to ventilation and room
i
cooling systems.
It was evident from the inspectors' discussions with
j
selected operators that there is a distinct difference in opinion regarding
j
what systems are considered essential support systems for operability of
parent systems / components. Therefore, a broader issue exists with how you
j
define and treat essential support equipment in general.
j
i
In view of the significance of operating in a condition prohibited by TS. and
i
i
considering the broader issues discussed in the preceding paragraph, this
violation was considered for escalated enforcement. However, considerirg the
j
detailed circumstances of the event against the criteria contained in the NRC
]
Enforcement Policy (10 CFR 2, Appendix C), we concluded that escalated
enforcement was not appropriate. The results of the enforcement evaluation
i
and review process relative to the violation referenced above were discussed
!
with Mr.1i. D. Wadley and other members of your. staff on August 6,1993.
You are required to respond to this letter and should follow the instruc; ions
5
specified in the enclosed Notice when preparing your response.
In your
j
response, you should document the specific actions taken and any additional
I
actions you plan to prevent recurrence.
In addition, you are requested to
address the broader concern noted above, relating to how you define and :reat
essential support equipment in general and how you intend to address that
i
concern. After reviewing your response to this Notice, including your
proposed corrective actions and the results of future inspections, the MC
j
will determine whether further NRC enforcement action is necessary to er.sure
compliance with NRC regulatory requirements.
-
'
/'
4
s
Northern States Power Company
3
In accordance with 10 CFR 2.790 of the NRC's " Rules of Practice," a copy of
this letter and its enclosures will be placed in the NRC Public Document Room.
The responses directed by this letter and the enclosed Notice are not subject
to the clearance procedures of the Office of Management and Budget as required
by the Paperwork Reduction Act of 1980, Pub. L. No.96-511.
We will gladly discuss any questions you have concerning this inspection.
Sincerely,
Q T~'O?
,- - r
,
np
EdEadG.Greenman, Director
Division of Reactor Projects
Enclosures:
Inspection Report
No. 50-306/93015(DRP)
cc w/ enclosure:
E. L. Watzl, Site Manager,
Prairie Island Site
M. Wadley, Plant Manager
OC/LFDCB
Resident Inspector, Rill Prairie
Island
Resident Inspector, RIII Monticello
t
John W. Ferman, Ph.D.,
Nuclear Engineer, MPCA
State Liaison Officer, State
of Minnesota
State Liaison Officer, State
of Wisconsin
Prairie Island, LPM, NRR
bcc
"Pu bli"
hR
RNU/F &}I
E-
(,. D (
RIII
I
EI
RI
ini
Jorgensen
DeF yet e
Pirok
5
-
Gr
V
VI~U
S l) 93
?f/7/73
f'Y
SG0005
u
o
l
.
.
,
i
Northern States Power Company
3
.l
l
,
.
In accordance with 10 CFR 2.790 of the NRC's " Rules of Practice," a copy of
f
this letter and its enclosures will be placed in the NRC Public Document Room.
j
i
The responses directed by this letter and the enclosed Notice are iiut subject
l
to the clearance procedur:s cf the Office of Management and Budget as r equired
i
by the Paper 3rk Reducticn Act of 1980, Pub. L. No.96-511.
We will glad!,, discuss any questions you have concerning this inspectian.
.
'
Sii.cerely,
i
d
.
--
- - - -
Edward G. Greenman, Director
Division of Reactor Projects
Enclosures: Notice of Violation
!
Inspection Report
No. 50-306/93015(DRP)
j
'
.
cc w/ enclosure
E. L. Watzl, Site Manager,
Prairie Island Site
}
M. Wadley, Plant Manager
OC/LFDCB
Resident Inspector, RIII Prairie
!
Island
Resident Inspector, RIII Monticello
John W. Ferman, Ph.D.,
j
Nuclear Engineer, MPCA
j
State Liaison Officer, State
-
e
'
of Minnesota
State Liaison Officer, State
of Wisconsin
,
Prairie Island, LPM. NRR
I
!
,
-
l
i
i
.
-
'