ML19259D506: Difference between revisions

From kanterella
Jump to navigation Jump to search
Created page by program invented by StriderTol
 
StriderTol Bot change
 
(2 intermediate revisions by the same user not shown)
Line 11: Line 11:
| contact person =  
| contact person =  
| document report number = GQL-0025, GQL-25, NUDOCS 7910240771
| document report number = GQL-0025, GQL-25, NUDOCS 7910240771
| document type = REPORTABLE OCCURRENCE REPORT (SEE ALSO AO,LER), TEXT-SAFETY REPORT
| document type = REPORTABLE OCCURRENCE REPORT (SEE ALSO AO LER), TEXT-SAFETY REPORT
| page count = 4
| page count = 4
}}
}}


=Text=
=Text=
{{#Wiki_filter:AEC DTS'Cv3UTION FOR PART 50 DOCKET MrrEPN4
{{#Wiki_filter:AEC DTS'Cv3UTION FOR PART 50 DOCKET MrrEPN4 (TD1?CTAR'r FOPJi)
            ,
CONTROL NO:
                                        -
4965 FILE:
(TD1?CTAR'r FOPJi)               _
ENVIRO FROM:
CONTROL NO:           4965
DATE CF DOC DATE REC'D LTR
    .
' MEMO RPT OTHER Metropolitan Edison Company Reading, Pennsylvania R. C. Arncid 5-31-74 6-4-74 X
                                                    *
TO:
* FILE:         ENVIRO FROM:                                       DATE CF DOC       DATE REC'D           LTR   ' MEMO           RPT     OTHER Metropolitan Edison Company Reading, Pennsylvania R. C. Arncid                                   5-31-74           6-4-74             X TO:                                           ORIG           CC       OTHER             SENT AEC PDR               XXX J. P. O'Reilly                             1 CLASS     UNCLASS         PROP INFO         INPUT         NO CTS REC'D                 DOCKET NO:
ORIG CC OTHER SENT AEC PDR XXX J. P. O'Reilly 1
XXX                                                     1               50-289 DESCRIPTION:                                                 ENCLOSURES:
CLASS UNCLASS PROP INFO INPUT NO CTS REC'D DOCKET NO:
Environmental Incident rpt #EI 50-289/74-1 (erroneously designated 24 hr rpt A0-74-5)                           .DONOT REMOVE of 5-26-74 in which an excessive negative rate of shange of river water differential temperature occurred                                             I             OEEGE PLANT NAME: THREE MILE ISLAND UNIT #1 1                      FCR ACTION /INFORMATION,               6-5-74     GMC BUTLER (L)           SCWENCER(L)             ZIDIANN(L)               [REGAN(E)
XXX 1
W/ Copies             W/1 Gpies info         W/ Copies                   W/ 2 Copies g CLARK (L)             STOLZ(L)               DICKER (E)
50-289 DESCRIPTION:
W/ Copies             W/ Copies               W/ Copies                   W/ Copies                 0     -
ENCLOSURES:
PARR(L)               VASSALLO(L)             KNIGHTON(E)
Environmental Incident rpt #EI 50-289/74-1 (erroneously designated 24 hr rpt A0-74-5)
  ':/ C pic:             ::/ C:pi::             ::/ C:pi::                 n/ C pic:                             //
.DONOT REMOVE of 5-26-74 in which an excessive negative rate of shange of river water differential temperature occurred I
KNIEL(L)               PURPLE (L)             YOUNGBLOOD(E)                                                         ,h, W/ Copies             W/ Copies               W/ Copies                   W/ Copies                                     d
OEEGE PLANT NAME: THREE MILE ISLAND UNIT #1 FCR ACTION /INFORMATION, 6-5-74 GMC 1
              ,
BUTLER (L)
INE?l:AL DISTRIBUTICN JtEG FILE                 JrECH REVIE'i     VDENTON                                               A/T IFD
SCWENCER(L)
/AEG PDR                   /HENDRIE             GRIMES               LIC ASST                         BFs.ITMA'1 GC, ROCM P-506A       SCHROEDER           GA144ILL                                             SALTZMAN DIGGS (L)
ZIDIANN(L)
/MUNTZING/ STAFF            MACCARY                 STIiER GEARIN (L)                     B. WRT CASE                       KNIGHT             BALLARD
[REGAN(E)
                                                                    /GOULBOURNE (L)                 PLAFS GIAMBUSSO                 PAWLICKI           SPANGLER LEE (L)                       MCDONALD BOYD                       SHAO MAIGRET (L)                   DUBE w/ Input MOORE (L)(IL'R)           STELLO             ENVIRO
W/ Copies W/1 Gpies info W/ Copies W/ 2 Copies g CLARK (L)
                                                                  / REED (E)
STOLZ(L)
DEYOUNG(L)(FWR)           HOUSTON             MULLER                                               NO SERVICE (L)
DICKER (E)
SKOVHOLT (L)               NOVAK               DICKER SHEPPARD (L)
W/ Copies W/ Copies W/ Copies W/ Copies 0
C. MILES GOLLER(L)                 ROSS               ICIIGHTON                                           KLECKER SLATER (E)
PARR(L)
P. COLLINS                 IPPOLITO           YOUNGBLOOD SMITH (L)                       EISMET DENI5E                     TEDESCO             REGAN TEETS (L)
VASSALLO(L)
EG OPR                 LONG                 ROJECT LDR WADE (E)
KNIGHTON(E)
AOR FILE
':/
[ FILE & REGIONLAINAS          (3)                ST. MARY (2)       WILLIA'4S (E)                   D. WO WSOS (2)
C pic:
MORRIS                     BENAROYA           HARLESS WILSON (L)               '
::/ C:pi::
                                                                                                  >   CO 7CO VOLlRER                                                             '   ,,) 7   (_ J O   .
::/ C:pi::
i                                          EXTE?JiAL DISTRIEUTIC:7                                                   y      __
n/ C pic:
      - LOCAL PDR HARRISBURC. PA           j
//,h, KNIEL(L)
      - TIC (A3ERUTHY)                   V(1) CCQtlX3-liATIONAL LA3'S ANL                         l-FDR-S AN/L/ ':"-
PURPLE (L)
1 - NSIC(EUCHA';AN)                                 J-ASL3P(E/U 31d;,y2 529)                   1-GERALD L:!J.C;0T 1 - ASL3                                           /1-W. PENSINGTO:7, ?= E-201 GT               Sacc HA"E:i'nr. L 3 1 - P. R. DAVIS (AEROJET NUCLEAR)                     1-CONSULTANT'S                             1-AG'4EC(Rut se m         a 16 - CYS ACIL: HOLDING                                   NEU11 ARK / BLLTE /AG3.iBI AN                 Ii- 3-l M . ST.
YOUNGBLOOD(E)
1-GERALD ULRIKSCN. . 02HL                 l-KD..MULLE2..F-30? ?
W/ Copies W/ Copies W/ Copies W/ Copies d
1-B & M SWINE 3RCAD, Pc E-201 GT                                   p 791024077/
INE?l:AL DISTRIBUTICN JtEG FILE JrECH REVIE'i VDENTON A/T IFD
/AEG PDR
/HENDRIE GRIMES LIC ASST BFs.ITMA'1 GC, ROCM P-506A SCHROEDER GA144ILL
/MUNTZING/ STAFF DIGGS (L)
SALTZMAN MACCARY STIiER GEARIN (L)
B. WRT CASE KNIGHT BALLARD
/GOULBOURNE (L)
PLAFS GIAMBUSSO PAWLICKI SPANGLER LEE (L)
MCDONALD BOYD SHAO MAIGRET (L)
DUBE w/ Input MOORE (L)(IL'R)
STELLO ENVIRO
/ REED (E)
DEYOUNG(L)(FWR)
HOUSTON MULLER NO SERVICE (L)
SKOVHOLT (L)
NOVAK DICKER C. MILES SHEPPARD (L)
GOLLER(L)
ROSS ICIIGHTON KLECKER SLATER (E)
P. COLLINS IPPOLITO YOUNGBLOOD EISMET SMITH (L)
DENI5E TEDESCO REGAN TEETS (L)
[ FILE & REGION (3)
EG OPR LONG ROJECT LDR WADE (E)
AOR FILE LAINAS ST. MARY (2)
WILLIA'4S (E)
D. WO WSOS (2)
MORRIS BENAROYA HARLESS WILSON (L)
> CO 7CO VOLlRER
',,) 7
(_ J O
.y i
EXTE?JiAL DISTRIEUTIC:7
- LOCAL PDR HARRISBURC. PA j
- TIC (A3ERUTHY)
V(1) CCQtlX3-liATIONAL LA3'S ANL l-FDR-S AN/L/ ':"-
1 - NSIC(EUCHA';AN)
J-ASL3P(E/U 31d;,y2 529) 1-GERALD L:!J.C;0T 1 - ASL3
/1-W. PENSINGTO:7, ?= E-201 GT Sacc HA"E:i'nr. L 3 1 - P. R. DAVIS (AEROJET NUCLEAR) 1-CONSULTANT'S 1-AG'4EC(Rut se m a 16 - CYS ACIL: HOLDING NEU11 ARK / BLLTE /AG3.iBI AN Ii-3-l M. ST.
1-GERALD ULRIKSCN.. 02HL l-KD..MULLE2..F-30? ?
1-B & M SWINE 3RCAD, Pc E-201 GT 791024077/
p


                      . . . _ _ _ _ .            _                -_ . . . - _ . _ . - _ _ _ _                      ._          _ _.                        _ _. . _ ._ .
A*(.g'f;;77;]
                                                                              ,.
l
    .
~
          *
a..,.
                    .
: s'n
                                  ~                            l A*(.g'f;;77;]
!cwn n.* rwns METROPOLITAN EDISON COMPANY
a .. , .              .
~
                                                                                                    -
-~.
                                                                                                      -
_-rcm.
: s'n .        !cwn n.* rwns METROPOLITAN EDISON COMPANY                                                     ~       -~.                             _-rcm.                          .,.
POST OFFICE BOX 542 RE ADING, PENNSYLVANf A 19603 TELEPHONE 215 - 929-3001 May 31, 19Th GQL 0025
---    - - . - - .                    --- -        . - _ - . . . . . . - . _ . . . . _ . . .              . _ . . _ .
/.
POST OFFICE BOX 542 RE ADING, PENNSYLVANf A 19603                                                                       TELEPHONE 215 - 929-3001 May 31, 19Th GQL 0025                                                                 '      /.
:,6 '
                                                                                                                                                                                  .
/.
                                                                                                                                    /.                                            :,6 '
''^
                                                                                                                                                                                    ' , . _'
j'
                                                                                                                                                                    .
/_
                                                                                                                                                                ''^
,' vt
j'               /_         ,
,., - r*; I:s,
                                                                                                                                                                        '
~
                                                                                                                                ;.
^.
                                                                                                                                              , .,,'- vt
g p.
                                                                                                                                            ,
s
                                                                                                                            ,                  g            r*; I:s ^.        ,
',w k,
                                                                                                                                                                              ,.      .-
*f
                                                                                                                                                                                          ~
~
                                                                                                                            ,_.                             ,
;y Mr. J. P. O'Reilly, Director y
                                                                                                                            '                                                  *          "
f~ N' Regulatory Operations, Region 1 N jd 2.)'
                                                                                                                              ;                                    ...                  ,
s 631 Park Avenue
                                                                                                                                                                                                ,
' " ~
                                                                                                                                                                      '
King of Prussia, Pennsylvani.t 19h06
* s                                           p.
                                                                                                                                                                            '
                                                                                                                                                                                          .
k,           . . . , .,            *f             ',w Mr. J. P. O'Reilly, Director                                                                                         y       ,
                                                                                                                                            ''
                                                                                                                                                      ~
                                                                                                                                                        .,                          ;y Regulatory Operations, Region 1                                                                                         s                                  f~ N' 631 Park Avenue N jd
                                                                                                                                          ,
                                                                                                                                              -
2.)'
                                                                                                                                                      ' " ~
King of Prussia, Pennsylvani.t                             19h06


==Dear Mr. O'Reilly:==
==Dear Mr. O'Reilly:==
Operating License DPR-50 Docket No. 50-289 In accordance with Environ =cntal Technical Specifications for the Three Mile Island Nuclear Station Unit 1, ve are reporting the following Environmental Incident (ref: inappropriately designated 2h hr. report A0-Th-5):
Operating License DPR-50 Docket No. 50-289 In accordance with Environ =cntal Technical Specifications for the Three Mile Island Nuclear Station Unit 1, ve are reporting the following Environmental Incident (ref: inappropriately designated 2h hr. report A0-Th-5):
(1) Reporting Nu=ber:                 E.I. 50-289/Th-1                                                                                                     __r (2a) Report Date:             May 31, 197h (2b) Occurrence Date:                 May 26, 197h                                                                           </
(1) Reporting Nu=ber:
                                                                                                                                                .)A wh                  WU
E.I. 50-289/Th-1
                                                                                                                                                                                        %'.
__r
U
.)A wh (2a) Report Date:
_
May 31, 197h WU U
JUN 04 % E (3)   Facility:           Three Mile Island Nuclear Generating Station, Unit'y                                                                       g.fu u., .:" ;
(2b) Occurrence Date:
                                                                                                                                                                                              '' Z
May 26, 197h
                                                                                                                                                                                            ,/C r
</
(h)   Identification of Incident:                                                                                         \b   y                  01 9
JUN 04 % E (3)
                                                                                                                                                                                      .N 9
Facility:
Excessive Nerative Rate of Change of River Water Differential                                                               ~'Q  '
Three Mile Island Nuclear Generating Station, Unit'y g.fu
y;~ Q -    4'N                ,.
'' Z r
Temeerature, which is a violatien of Technical Specifications, paragraph 2.1.a(2), and constitutes exceeding a liciting condition for operation.
u.,.:" ;
(5)   Conditions Prior to Occurrence:                                     Reactor cooldown           to lh00 F in progress with major plant parameters as follows:
,/C (h)
Power:                   Core:             0                                                                 1459 259 Elec:             O dbb REGULATORY.DOCIGTFILE COPY
Identification of Incident:
\\b 01 9 9
.N 4'N y
~ y;~ Q -
'Q Excessive Nerative Rate of Change of River Water Differential Temeerature, which is a violatien of Technical Specifications, paragraph 2.1.a(2), and constitutes exceeding a liciting condition for operation.
(5)
Conditions Prior to Occurrence:
Reactor cooldown to lh0 F in 0
progress with major plant parameters as follows:
1459 259 Power:
Core:
0 Elec:
O dbb REGULATORY.DOCIGTFILE COPY


                                              .
4
4   , ,
- 'p -
                    .
m._
    *
....,..m,...w..
                                                                - 'p -
..., _ sx,.-w..:_
m._   ,
R.C. Flow:
          - . . _ .      _ _ . _ . . . . . _ _ _ - . _ -        , .    ....,..m,...w..     . .., _ sx,.-w. .:_
2800 GPM--Decay Heat Removal System R.C. Pressure:
R.C. Flow:                           2800 GPM--Decay Heat Removal System R.C. Pressure:                       270 psig
270 psig R.C. Tempa 190 F
                                                                                                    ~
~
R.C. Tempa                           190 F PRZR Level:                           115" PRZR Temp.:                           h15 F (6) Description of Incident: During cooldown of the Reactor Coolant System, operations personnel noticed that the service vatar discharge (effluent) temperature to the river was increasing abave the river' vater (influent) temperature. They then initiated action to decrease the effluent temperature by starting a 74echanical Draft Cooling Tover pu=p and fan.                   This action resulted in the effluent to influent differential temperature decreasing at a rate of 7 F/hr. Upor indication that the differential temperature had decreased at a rate exceeding the 20 F/hr. Environmental Technical Specifications limit, action was taken to stop further decrease of the effluent temperature by securing the operating fan on the Mechanical Draft Cooling Tover.
PRZR Level:
115" PRZR Temp.:
h15 F (6) Description of Incident: During cooldown of the Reactor Coolant System, operations personnel noticed that the service vatar discharge (effluent) temperature to the river was increasing abave the river' vater (influent) temperature.
They then initiated action to decrease the effluent temperature by starting a 74echanical Draft Cooling Tover pu=p and fan.
This action resulted in the effluent to influent differential temperature decreasing at a rate of 7 F/hr.
Upor indication that the differential temperature had decreased at a rate 0
exceeding the 2 F/hr. Environmental Technical Specifications limit, action was taken to stop further decrease of the effluent temperature by securing the operating fan on the Mechanical Draft Cooling Tover.
(7) Designation of Apparent Cause of Incident:
(7) Designation of Apparent Cause of Incident:
(a) Material, in that the service water differential temperature alarm was inoperative, and (b) Personnel, in that individuals were inexperienced in the opera-tion of the Mechanical Draft Cooling Tower, which led to their failing to exercise sufficient caution in cooling tower opera-tion and service water temperature monitoring.
(a) Material, in that the service water differential temperature alarm was inoperative, and (b) Personnel, in that individuals were inexperienced in the opera-tion of the Mechanical Draft Cooling Tower, which led to their failing to exercise sufficient caution in cooling tower opera-tion and service water temperature monitoring.
(8) Analysis of Incident:                       The effluent temperature stopped decreasing and stabilized at 63 F shortly after securing the Mechanical Draft Cooling Tower fan, thus bringing the rate of change of differential temperature to within the Environmental Technical Specifications limit. Visual inspection of the river immediately following the incident revealed no indication of environmental damage.                                    .
(8) Analysis of Incident:
(9)   Corrective Action: Operations personnel took immediate actions as described in the above analysis and reported the incident to the Plant Superintendent, who in turn notified the Vice President of Generation.             Long term corrective action implemented is as follows:
The effluent temperature stopped decreasing and stabilized at 63 F shortly after securing the Mechanical Draft Cooling Tower fan, thus bringing the rate of change of differential temperature to within the Environmental Technical Specifications limit. Visual inspection of the river immediately following the incident revealed no indication of environmental damage.
(9)
Corrective Action: Operations personnel took immediate actions as described in the above analysis and reported the incident to the Plant Superintendent, who in turn notified the Vice President of Generation.
Long term corrective action implemented is as follows:
(a) The service water differential terperature alarm has been repaired.
(a) The service water differential terperature alarm has been repaired.
(b) The Mechanical Draft Cooling Tower vill be revised to include
(b) The Mechanical Draft Cooling Tower vill be revised to include
                    ' precautions on the use and control of the towers during cool-down.
' precautions on the use and control of the towers during cool-down.
                                                              '
1459 260
1459 260


e~.
e~.
                            ,        . . .
~
  ~                                         '
~.
.                                        ~          (c) The T E-1 Supervisor of Operations vill counsel all TMI-1 Operations Departcent Supervisory Personnel on
(c) The T E-1 Supervisor of Operations vill counsel all TMI-1 Operations Departcent Supervisory Personnel on 1.
: 1. the need to closely monitor the service water differential temperature during cooldown, and
the need to closely monitor the service water differential temperature during cooldown, and 2.
: 2. the necessity to use caution in operating the Mechanical Draft Cooling Tower pumps and fans.
the necessity to use caution in operating the Mechanical Draft Cooling Tower pumps and fans.
This action has been reviewed and concurred in by the Manager of Generation Engineering.
This action has been reviewed and concurred in by the Manager of Generation Engineering.
(10) Failure Data:   Not Applicable.
(10) Failure Data:
Sincerely, t'1,         ;
Not Applicable.
C. dLh Vice President-Generation RCA:D:!G:eg ec: Director Directorate of Licensing U. S. Atocic Energy Co==ission Washington, D.C.     205h5 File 20.1.1/7.7.3.8.1 1459 261
Sincerely, t'1, C.
                                                                          .}}
dLh Vice President-Generation RCA:D:!G:eg ec:
Director Directorate of Licensing U. S. Atocic Energy Co==ission Washington, D.C.
205h5 File 20.1.1/7.7.3.8.1 1459 261
.}}

Latest revision as of 14:52, 3 January 2025

Environ Incident 50-289/74-01:on 740526,excessive Negative Change Rate of River Water Differential Temp Violated Ets. Caused by Inexperienced Personnel Operating Mechanical Draft Cooling Tower & Inoperative Differential Temp Alarm
ML19259D506
Person / Time
Site: Crane 
Issue date: 05/31/1974
From: Arnold R
METROPOLITAN EDISON CO.
To:
References
GQL-0025, GQL-25, NUDOCS 7910240771
Download: ML19259D506 (4)


Text

AEC DTS'Cv3UTION FOR PART 50 DOCKET MrrEPN4 (TD1?CTAR'r FOPJi)

CONTROL NO:

4965 FILE:

ENVIRO FROM:

DATE CF DOC DATE REC'D LTR

' MEMO RPT OTHER Metropolitan Edison Company Reading, Pennsylvania R. C. Arncid 5-31-74 6-4-74 X

TO:

ORIG CC OTHER SENT AEC PDR XXX J. P. O'Reilly 1

CLASS UNCLASS PROP INFO INPUT NO CTS REC'D DOCKET NO:

XXX 1

50-289 DESCRIPTION:

ENCLOSURES:

Environmental Incident rpt #EI 50-289/74-1 (erroneously designated 24 hr rpt A0-74-5)

.DONOT REMOVE of 5-26-74 in which an excessive negative rate of shange of river water differential temperature occurred I

OEEGE PLANT NAME: THREE MILE ISLAND UNIT #1 FCR ACTION /INFORMATION, 6-5-74 GMC 1

BUTLER (L)

SCWENCER(L)

ZIDIANN(L)

[REGAN(E)

W/ Copies W/1 Gpies info W/ Copies W/ 2 Copies g CLARK (L)

STOLZ(L)

DICKER (E)

W/ Copies W/ Copies W/ Copies W/ Copies 0

PARR(L)

VASSALLO(L)

KNIGHTON(E)

':/

C pic:

/ C:pi::
/ C:pi::

n/ C pic:

//,h, KNIEL(L)

PURPLE (L)

YOUNGBLOOD(E)

W/ Copies W/ Copies W/ Copies W/ Copies d

INE?l:AL DISTRIBUTICN JtEG FILE JrECH REVIE'i VDENTON A/T IFD

/AEG PDR

/HENDRIE GRIMES LIC ASST BFs.ITMA'1 GC, ROCM P-506A SCHROEDER GA144ILL

/MUNTZING/ STAFF DIGGS (L)

SALTZMAN MACCARY STIiER GEARIN (L)

B. WRT CASE KNIGHT BALLARD

/GOULBOURNE (L)

PLAFS GIAMBUSSO PAWLICKI SPANGLER LEE (L)

MCDONALD BOYD SHAO MAIGRET (L)

DUBE w/ Input MOORE (L)(IL'R)

STELLO ENVIRO

/ REED (E)

DEYOUNG(L)(FWR)

HOUSTON MULLER NO SERVICE (L)

SKOVHOLT (L)

NOVAK DICKER C. MILES SHEPPARD (L)

GOLLER(L)

ROSS ICIIGHTON KLECKER SLATER (E)

P. COLLINS IPPOLITO YOUNGBLOOD EISMET SMITH (L)

DENI5E TEDESCO REGAN TEETS (L)

[ FILE & REGION (3)

EG OPR LONG ROJECT LDR WADE (E)

AOR FILE LAINAS ST. MARY (2)

WILLIA'4S (E)

D. WO WSOS (2)

MORRIS BENAROYA HARLESS WILSON (L)

> CO 7CO VOLlRER

',,) 7

(_ J O

.y i

EXTE?JiAL DISTRIEUTIC:7

- LOCAL PDR HARRISBURC. PA j

- TIC (A3ERUTHY)

V(1) CCQtlX3-liATIONAL LA3'S ANL l-FDR-S AN/L/ ':"-

1 - NSIC(EUCHA';AN)

J-ASL3P(E/U 31d;,y2 529) 1-GERALD L:!J.C;0T 1 - ASL3

/1-W. PENSINGTO:7, ?= E-201 GT Sacc HA"E:i'nr. L 3 1 - P. R. DAVIS (AEROJET NUCLEAR) 1-CONSULTANT'S 1-AG'4EC(Rut se m a 16 - CYS ACIL: HOLDING NEU11 ARK / BLLTE /AG3.iBI AN Ii-3-l M. ST.

1-GERALD ULRIKSCN.. 02HL l-KD..MULLE2..F-30? ?

1-B & M SWINE 3RCAD, Pc E-201 GT 791024077/

p

A*(.g'f;;77;]

l

~

a..,.

s'n

!cwn n.* rwns METROPOLITAN EDISON COMPANY

~

-~.

_-rcm.

POST OFFICE BOX 542 RE ADING, PENNSYLVANf A 19603 TELEPHONE 215 - 929-3001 May 31, 19Th GQL 0025

/.

,6 '

/.

^

j'

/_

,' vt

,., - r*; I:s,

~

^.

g p.

s

',w k,

  • f

~

y Mr. J. P. O'Reilly, Director y

f~ N' Regulatory Operations, Region 1 N jd 2.)'

s 631 Park Avenue

' " ~

King of Prussia, Pennsylvani.t 19h06

Dear Mr. O'Reilly:

Operating License DPR-50 Docket No. 50-289 In accordance with Environ =cntal Technical Specifications for the Three Mile Island Nuclear Station Unit 1, ve are reporting the following Environmental Incident (ref: inappropriately designated 2h hr. report A0-Th-5):

(1) Reporting Nu=ber:

E.I. 50-289/Th-1

__r

.)A wh (2a) Report Date:

May 31, 197h WU U

(2b) Occurrence Date:

May 26, 197h

</

JUN 04 % E (3)

Facility:

Three Mile Island Nuclear Generating Station, Unit'y g.fu

Z r

u.,.:" ;

,/C (h)

Identification of Incident:

\\b 01 9 9

.N 4'N y

~ y;~ Q -

'Q Excessive Nerative Rate of Change of River Water Differential Temeerature, which is a violatien of Technical Specifications, paragraph 2.1.a(2), and constitutes exceeding a liciting condition for operation.

(5)

Conditions Prior to Occurrence:

Reactor cooldown to lh0 F in 0

progress with major plant parameters as follows:

1459 259 Power:

Core:

0 Elec:

O dbb REGULATORY.DOCIGTFILE COPY

4

- 'p -

m._

....,..m,...w..

..., _ sx,.-w..:_

R.C. Flow:

2800 GPM--Decay Heat Removal System R.C. Pressure:

270 psig R.C. Tempa 190 F

~

PRZR Level:

115" PRZR Temp.:

h15 F (6) Description of Incident: During cooldown of the Reactor Coolant System, operations personnel noticed that the service vatar discharge (effluent) temperature to the river was increasing abave the river' vater (influent) temperature.

They then initiated action to decrease the effluent temperature by starting a 74echanical Draft Cooling Tover pu=p and fan.

This action resulted in the effluent to influent differential temperature decreasing at a rate of 7 F/hr.

Upor indication that the differential temperature had decreased at a rate 0

exceeding the 2 F/hr. Environmental Technical Specifications limit, action was taken to stop further decrease of the effluent temperature by securing the operating fan on the Mechanical Draft Cooling Tover.

(7) Designation of Apparent Cause of Incident:

(a) Material, in that the service water differential temperature alarm was inoperative, and (b) Personnel, in that individuals were inexperienced in the opera-tion of the Mechanical Draft Cooling Tower, which led to their failing to exercise sufficient caution in cooling tower opera-tion and service water temperature monitoring.

(8) Analysis of Incident:

The effluent temperature stopped decreasing and stabilized at 63 F shortly after securing the Mechanical Draft Cooling Tower fan, thus bringing the rate of change of differential temperature to within the Environmental Technical Specifications limit. Visual inspection of the river immediately following the incident revealed no indication of environmental damage.

(9)

Corrective Action: Operations personnel took immediate actions as described in the above analysis and reported the incident to the Plant Superintendent, who in turn notified the Vice President of Generation.

Long term corrective action implemented is as follows:

(a) The service water differential terperature alarm has been repaired.

(b) The Mechanical Draft Cooling Tower vill be revised to include

' precautions on the use and control of the towers during cool-down.

1459 260

e~.

~

~.

(c) The T E-1 Supervisor of Operations vill counsel all TMI-1 Operations Departcent Supervisory Personnel on 1.

the need to closely monitor the service water differential temperature during cooldown, and 2.

the necessity to use caution in operating the Mechanical Draft Cooling Tower pumps and fans.

This action has been reviewed and concurred in by the Manager of Generation Engineering.

(10) Failure Data:

Not Applicable.

Sincerely, t'1, C.

dLh Vice President-Generation RCA:D:!G:eg ec:

Director Directorate of Licensing U. S. Atocic Energy Co==ission Washington, D.C.

205h5 File 20.1.1/7.7.3.8.1 1459 261

.