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NPS_Watch Apr 15, 2019
#1
The Daily Dose - Exposing the nuclear power industry while the nuclear power industry exposes you.

There are 9 EN(s) today, 4 associated with power stations.

[  ]

NRC Event Notices for April 15, 2019 |
https://www.nrc.gov/reading-rm/doc-colle...415en.html

[  ]

--------------------------------------------------------------------------------------------------------------------------
----------------- Power Reactor Event Notices
--------------------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------------------------------------------
----------- [ Current event for TN_Sequoyah_1 ]

20190414 | TN_Sequoyah_1 | AUTOMATIC REACTOR TRIP DUE TO MAIN FEEDWATER PUMP TRIP |
https://www.nrc.gov/reading-rm/doc-colle...ml#en53999


"At 0320 EDT, April 14, 2019,Sequoyah Unit 1 experienced an automatic reactor trip.

The event was initiated by the trip of the 1A main feedwater pump.

During the automatic unit runback, an automatic reactor trip was initiated due to low-low level in Steam Generator number 3.

"The Auxiliary Feedwater System (AFWS) automatically actuated as required when the expected post-trip feedwater isolation actuated.

Reactor Coolant System temperature is being maintained by the AFWS and the steam dump system.

During this operational cycle, one control Rod Position Indicator (RPI) for core position E-5 in shutdown bank 'A' has been inoperable, and the appropriate Condition and Required Actions of [Technical Specification Limiting Condition of Operation] 3.1.7 were complied with. 

Due to this inoperable RPI, the associated shutdown rod is conservatively assumed to be full out and untrippable.

Consequently, boration was required to establish adequate shutdown margin.

All other Control and Shutdown rods fully inserted.
[
 This makes it seem like the CR indicator was not working, but I think they knew that CR was stuck ( how long they knew it was stuck is unclear ) and were running the unit anyway.
 IIRC boron is highly corrosive to steel ( research the hole in DavisBesse ) so the entire primary loop is now being affected.
 The borated coolant may not eat thru any of the components quickly, but something somewhere may fail at a later date.
 
]

All safety systems responded as designed. No primary or secondary safety valves actuated during or after the reactor trip.

The unit is currently stable in Mode 3. Unit 1 is in a normal shutdown electrical alignment.

"There was no impact on Unit 2.

"Due to the Reactor Protection System actuation while critical,this event is being reported as a four-hour,
non-emergency notification per 10 CFR 50.72(b)(2)(iv)(B)
and in accordance with 10 CFR 50.72(b)(3)(iv)(A) as an event that results in a valid actuation of the AFW system.

"There was no impact on the health and safety of the public or plant personnel.

"The NRC Senior Resident Inspector has been notified."


----------- [ 2019 event history for TN_Sequoyah ]

20190412 | TN_Sequoyah_1 | PART 21 REPORT - OVERHEATING AND FAILURE OF TRANSFORMERS |
https://www.nrc.gov/reading-rm/doc-colle...ml#en53993


----------------------------------------------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------------------------------------------
----------- [ Current event for NY_NineMilePoint_1 ]


20190414 | NY_NineMilePoint_1 | AUTOMATIC REACTOR SCRAM AND SPECIFIED SYSTEM ACTUATION |
https://www.nrc.gov/reading-rm/doc-colle...ml#en53998

"On April 14, 2019 at 0003 [EDT], Nine Mile Point Unit 1 experienced an automatic reactor scram during reactor startup.

The cause of the automatic scram was due to high [Reactor Pressure Vessel] pressure
following closure of the turbine stop valves.

All control rods fully inserted and all plant systems responded per design following the scram.

"Following the automatic scram, the High Pressure Coolant Injection (HPCI) System automatically initiated as expected.

At Nine Mile Point Unit 1, a HPCI System actuation signal on low Reactor Pressure Vessel (RPV) level
is normally received following a reactor scram, due to level shrink.

HPCI is a flow control mode of the normal feedwater systems, and is not an Emergency Core Cooling System.

At 0004, RPV level was restored above the HPCI System low level actuation set point
and the HPCI System initiation signal was reset.

Pressure control was established on the Turbine Bypass Valves, the preferred system.

No Electromatic Relief Valves actuated due to this scram.

"Nine Mile Point Unit 1 is currently in Hot Shutdown, with reactor water level and pressure maintained within normal bands.

The offsite grid is stable with no grid restrictions or warnings in effect.

"The unit is currently implementing post scram recovery procedures."

The NRC Resident Inspector has been notified. The Licensee will notify the State of New York.


----------- [ 2019 event history for NY_NineMilePoint ]


20190413 | NY_NineMilePoint_1 | Exit RFO ( 26 / 21 )

20190322 | NY_NineMilePoint_1 | Begin RFO ( 01 / 21 )

[ no previous ENs for this site in 2019 ]

----------------------------------------------------------------------------------------------------------------------------------------------------

--------------------------------------------------------------------------------------------------------------------------
----------- [ Current event for MN_Monticello_1 ]

20190412 | MN_Monticello_1 | HIGH ENERGY LINE BREAK DOOR FOUND IN INCORRECT POSITION RESULTING IN LPCI AND CORE SPRAY BEING INOPERABLE |
https://www.nrc.gov/reading-rm/doc-colle...ml#en53997


"At approximately 1815 CDT on April 12, 2019, High Energy Line Break (HELB) Door-410A in the Reactor Building
was discovered in the closed position.

HELB Door-410B was previously closed for maintenance.

Either Door-410A or Door-410B must be open to support the current HELB analyses.

With both doors closed, this is considered an unanalyzed condition resulting in the loss of a post-HELB safe shutdown path.

"With Door-410A and Door-410B closed, LPCI [Low Pressure Coolant Injection] and Core Spray injection valves in both divisionsare no longer considered available.

"This condition is being reported under 10 CFR 50.72(b)(3)(ii) as an unanalyzed condition
that significantly degrades plant safety and 10 CFR 50.72(b)(3)(v) as an event or condition
that could have prevented the fulfillment of a safety function.

"The condition was resolved at approximately 1845 CDT on April 12, 2019 when Door-410A was blocked open.

The health and safety of the public was not affected by this condition.

"The NRC Resident has been notified."


----------- [ 2019 event history for MN_Monticello ]

20190322 | MN_Monticello_1 | Update PART 21 - POTENTIAL DEFECT IN VIKERS VOLTAGE REGULATOR SYSTEM |
https://www.nrc.gov/reading-rm/doc-colle...ml#en53846

20190124 | MN_Monticello_1 | PART 21 - POTENTIAL DEFECT IN VIKERS VOLTAGE REGULATOR SYSTEM |
https://www.nrc.gov/reading-rm/doc-colle...ml#en53846

[ no previous ENs for this site in 2019 ]

----------------------------------------------------------------------------------------------------------------------------------------------------

----------------------------------------------------------------------------------------------------------------------------------------------------
------------[ PART 21 ] - These ENs are for issues that involve multiple site/reactor units
----------------------------------------------------------------------------------------------------------------------------------------------------

20190412 | TN_Sequoyah_1;2 | PART 21 REPORT - OVERHEATING AND FAILURE OF TRANSFORMERS |
https://www.nrc.gov/reading-rm/doc-colle...ml#en53993


The following was received via e-mail:

"COMPONENT DESCRIPTION: AMETEK part number 80-315382-90, T801 main transformer.

"PROBLEM YOU COULD SEE: Overheating and failure of transformers installed in equipment with 0.7 power factor load requirements

"CAUSE: The inverters on AMETEK job number C72143 were required to support a 0.7 power factor load.

To meet this requirement, CVT capacitors were added which led to overcurrent on the capacitor current windings and overheating.

The overheating led to a breakdown in insulation between windings, causing a premature failure of the transformer set and inverter relative to its 40-year qualification life.

"EFFECT ON SYSTEM PERFORMANCE: The overheating accelerates the degradation of the insulation between windings and eventually leads to shorting. This will cause an inverter failure and require the load to be transferred to bypass.

"ACTION REQUIRED: This is the only instance AMETEK has experienced for this issue. Therefore, action is only required for the equipment on AMETEK job number C72143, located at TVA Sequoyah. New transformers have been provided as replacements that require fewer capacitors, contain additional venting to improve cooling, and include larger winding material to reduce current density. The main transformers (T801) installed in the serial numbers associated with this job (C72143-0111 through 0911) should be replaced to prevent any similar occurrences.

"AMETEK SOLIDSTATE CONTROLS CORRECTIVE ACTION: AMETEK has enhanced this particular transformer design to improve cooling and reduce capacitor current. Additionally, corrective action #175 has been issued in AMETEK's system.

"If you have any questions, please contact [ contact info on NRC site ]

Sequoyah is the only site affected by this Part 21 Report.


----------------------------------------------------------------------------------------------------------------------------------------------------
----------------- Other reactor info from daily power tracking
-----------------------------------------------------------------------------------------------------------------


Region 1
 
NY_Indian_Point_3 @ 100 % unch from 100 % Sunday; 100 % Saturday
[ Completed ( 29 / 30 ) 20190312 ]

PA_Limerick_2 @ 0 % [ Begin RFO ( 01 / 20 ) 20190415 ]
[ Expect RPV OPEN Friday ]

CT_Millstone_3 @ 0 % [ Begin RFO ( 04 / 33 ) RFO plan start 20190418 ]
[ unit may have entered RFO early ]

NY_Nine_Mile_Point_1 @ 5 % [ Exit RFO ( 26 / 21 ) ] missed planned restart date, failed restart

PA_Peach_Bottom_3 @ 100 % unch from 100 % Sunday; 77 % Saturday
[ no EN. unk reason fro power drop. ]

NJ_Salem_1 @ 0 % [ Begin RFO ( 03 / 28 ) ] started early
[ Expect RPV OPEN Wednesday ]

PA_Susquehanna_2 @ 0 % [ RPV OPEN ( 24 / 35 ) 20190323 ]


Region 2

AL_Browns_Ferry_2 @ 75 % up from 66 % Sunday; 66 % Saturday
[ Exit RFO ( 39 / 25 ) ] missed planned restart date ]

NC_Brunswick_1 @ 100 % unch from 100 % Sunday; 77 % Saturday

NC_Brunswick_2 @ 50 % down from 52 % Sunday; 21 % Saturday [ exit RFO ( 28 / 28 ) ]
 [ recovering from ]
 MANUAL REACTOR SCRAM AND SPECIFIED SYSTEM ACTUATION |
 https://www.nrc.gov/reading-rm/doc-colle...ml#en53966

AL_Farley_1 @ 97 % up from 96 % Sunday; 96 % Saturday
[ no EN, unk reason for power drop. ]

AL_Farley_2 @ 0 % [ RPV OPEN ( 08 / 28 ) 20190405 ]

NC_McGuire_1 @ 0 % [ RPV OPEN ( 24 / 31 ) 20190323 ]

TN_Sequoyah_1 @ 0 %
 AUTOMATIC REACTOR TRIP DUE TO MAIN FEEDWATER PUMP TRIP |
 https://www.nrc.gov/reading-rm/doc-colle...ml#en53999

VA_NorthAnna_2 @ 99 % unch from 99 % Sunday; 99 % Saturday
[ Exit RFO ( 37 / 36 ) ] missed planned restart date

FL_Turkey_Point_4 @ 95 % up from 63 % Sunday; 48 % Saturday
[ Exit RFO ( 30 / 28 ) 20190311, missed planned restart date ]

TN_Watts_Bar_2 @ 0 % [ Begin RFO ( 03 / 26 ) 20190413 ]
[ Expect RPV OPEN Wednesday ]


Region 3

IL_Byron_2 @ 0 % [ RPV OPEN ( 08 / 18 ) 20190408 ]

IL_Clinton_1 @ 98 %
[ 98-99 % are this units normal thermal power range. ]

MI_DC_Cook_1 @ 0 % [ RPV OPEN ( 41 / 30 ) 20190306  ]
[ missed planned restart date ]

IA_Duane_Arnold_1 @ 96 % up from 62 % Sunday; 100 % Saturday
[ no EN, unk reason for power drop. ]

MN_Monticello_1 @ 0 %  [ Begin RFO ( 02 / 30 ) 20190413 ]
[ expect RPV OPEN Thursday ]

WI_Point_Beach_1 @ 0 % [ RPV OPEN ( 24 / 26 ) 20190322 ]



Region 4

MO_Callaway_1 @ 0 % [ RPV OPEN ( 14 / 42 ) 20190401; no coastdown 24hr SD

WA_Columbia_2 100 % up from 99 % Sunday; 100 % Saturday
[ no EN, unk reason for power drop. ]
[ may be power suppression testing prior to coastdown/shutdown for upcoming RFO ]

TX_ComanchePeak_1 @ 88 % [ coastdown to RFO 20190407 ] missed planned start date ]

MS_GrandGulf_1 @ 94 % unch from 94 % Sunday; 94 % Saturday
[ no EN, unk reason for power drop. ]
e
AZ_PaloVerde_1 @ 0 % [ RPV OPEN ( 10 / 30 )

LA_RiverBend_1 @ 0 % [ RPV OPEN ( 17 / 34 ]


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[ There is/are currently 9 unit(s) with the RPV OPEN - ref the 2019 Spring Refueling Outage Schedule and Status ]

posted by Staup Knewkinus a Dane Gerous production. All human rights reserved.
 
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