March 27th, 2011 – 1800 EDT – USNRC Emergency Operations Center Status Update

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Current Understanding of Dapanese Facilities

(This information is compiled from the NRC in-country team, TEP CO press releases, NISA press releases, Japan Atomic Industrial Forum (JAIF) compiled data and assessments, International Atomic Energy Agency (IAEA) information releases, Federation of Electric Power Companies of Japan, World Association of Nuclear Operators, Department of Energy (DOE) and others.)

Fukushima Daiichi

The Japanese national government instructed evacuation for local residents within a 20km radius of the site boundary and sheltering in place out to 30 km. IAEA confirms a no-fly zone out to 30 km around the Fukushima Daiichi plant. Japanese government officials have recommended to residents living within 20 to 30 km of the site to voluntarily evacuate their homes – not because of changing conditions at the site – but because of increasingly difficult logistical issues.

Meteorological information obtained by PMT through NARAC and other sources indicate that a 360 degree wind shift has occurred over the duration of the accident (on March 11).

Current forecast meteorological data appears to indicate that winds are primarily from the west (headed offshore) and should generally continue offshore through Thursday, March 31, 2011.

STATUS as of1800 EDT, March 27,2011 – (0700 Japan, March 28)

Unit 1 – (NRC Priority: 1)

Core Status: Damaged, fuel partially or fully exposed (Source: JAIF, NISA, TEPCO).

The volume of sea water injected to cool the core has left enough salt to fill the lower plenum to the core plate (Source: GEH, US Industry).

Vessel temperatures 1430C at bottom drain, 2250C at FW nozzle (Source: NISA)

RPV at 55 psig (increasing trend), DW and torus pressure at 24.5 psig (decreasing trend) (Source: NISA).

Core Cooling: Fresh water injection initiated at 1537 JST on March 25, injecting through FW 120 L/min or 31.7 g/m (Source: NISA).

Recirculation pump seals have likely failed. (Source: GEH)

Primary Containment: Not damaged, 24.5 psig (TEPCO was considering venting on March 24)

Secondary Containment: Severely damaged (hydrogen explosion)

Spent Fuel Pool: Fuel covered, no seawater injected (Source: JAIF, NISA, TEPCO)

All fuels in this pool are over 12 years old and have very little heat input ( (Source: DOE).

Rad Levels: DW 4780 R/hr, Torus 3490 R/hr (source instruments unknown), Outside plant: 16 mR/hr at main gate (slight trend downward) (Source: MEXT)

Power: Electric power available, equipment testing in progress (Source: JAIF, NISA, TEPCO)

External AC power to the Main Control Room of Unit 1 became available at 1130 JST on March 24, 2011. Lighting operating in Main Control Room.

Unit 2 – (NRC Priority: 2)

Core Status: Damaged, fuel partially or fully exposed (Source: JAIF, NISA, TEPCO).

Bottom head temperature 111°C, feed water nozzle temperature 1241C (Source: JAIF, NISA, TEPCO).

Core Cooling: Fresh water with boric acid injection as of 1010 JST on March 26 (TEPCO),

Recirculation pump seals have likely failed. (Source: GEH)

Primary Containment: Damage suspected (Source: JAIF, NISA, TEPCO)

Secondary Containment: Damaged (Source: JAIF, NISA, TEPCO), blowout panels removed from side of reactor building to reduce hydrogen buildup. (Source: visual)

Spent Fuel Pool: Fuel covered, seawater injected on March 20, fuel pool temperature 670C (Source: JAIF, NISA, TEPCO)

Rad Levels: DW 4560 R/hr; Torus 154 R/hr (source instruments unknown); Outside plant: 16 mR/hr at main gate (slight trend downward) (Source: MEXT)

Power: External AC power has reached the unit; checking integrity of equipment before energizing.

Unit 3 – (NRC Priority: 3)

Core Status: Damaged, fuel partially or fully exposed (Source: JAIF, NISA, TEPCO).

Bottom head temperature 1220C, FW nozzle temperature 14 10C: (Source: NISA 0800 JST March 27)

Core Cooling: Freshwater injection (58 gpm) via fire line initiated 1802 JST March 25 (Source: NISA)

Seawater injection through RHR, Recirculation pump seals have likely failed. (Source: GEH)

Primary Containment: Damage suspected (Source: NISA, TEPCO). “Not damaged” (Source:JAIF).

Need to resolve.

Secondary Containment: Damaged (Source: JAIF, NISA, TEPCO)

Spent Fuel Pool: Low water level (Source: JAIF, NISA, TEPCO), spraying and pumping sea water into the SFP via the Cooling and Purification Line (Source: NISA)

Rad Levels: DW 5100 RPhr, torus 150 R/hr (INPO source instruments unknown); Outside plant: 16 mR/hr at main gate (slight trend downward) (Source: MEXT); 100 R/hr debris outside Rx building (covered).

Power: External AC power has reached the unit; checking integrity of equipment before energizing. Lighting is operating in Main Control Room.

Unit 4 – (NRC Priority: 4)

Core Status: Offloaded 105 days at time of accident (Source: JAIF, NISA, TEPCO)

Core Cooling: Not necessary (Source: JAIF, NISA, TEPCO)

Primary Containment: Not applicable (Source: JAIF, NISA, TEPCO)

Secondary Containment: Severely damaged, hydrogen explosion. (Source: JAIF, NISA, TEPCO)

Spent Fuel Pool: Low water level, spraying with sea water, hydrogen from the fuel pool exploded, fuel pool is cool heating up very slowly (Source: JAIF, NISA, TEPCO)

Temperature is unknown (Source: NISA).

Video was to be taken of SFP pool on March 24 (Source: unverified)

Power: External AC power has reached the unit; checking electrical integrity of equipment before energizing. (Source: JAIF, NISA, TEPCO)

Unit 5 – (NRC Priority: 5)

Core Status: In vessel (Source: JAIF, NISA, TEPCO)

Core Cooling: Functional (Source: JAIF, NISA, TEPCO)

Primary Containment: Functional (Source: JAIF, NISA, TEPCO)

Secondary Containment: Vent hole drilled in rooftop to avoid hydrogen build up (Source: JAIF, NISA, TEPCO)

Spent Fuel Pool: Fuel pool cooling functional, RHR pump repaired, temperature 301C (Source: NISA)

Power: External AC power supplying the unit, diesel generators available. (Source: JAIF, NISA, TEPCO)

Unit 6 – (NRC Priority: 6)

Core Status: In vessel (Source: JAIF, NISA, TEPCO)

Core Cooling: Functional (Source: JAIF, NISA, TEPCO)

Primary Containment: Functional (Source: JAIF, NISA, TEPCO)

Secondary Containment: Vent hole drilled in rooftop to avoid hydrogen build up (Source: JAIF, NISA, TEPCO)

Spent Fuel Pool: Fuel pool cooling functional, temperature 211C (Source: JAIF)

Power: External AC power supplying the unit, diesel generators available. (Source: JAIF, NISA, TEPCO)

Common Spent Fuel Pool (NRC priority: 7):

6,000 bundles (Source: GEH); water level maintained at 391C (Source: IAEA); water spray started at 2137 EDT March 20 (Source: NISA);

normal cooling started 1805 JST March 24 (Source: NISA)

Electrical Power (NRC priority: 7):

Offsite power connected to Units 1-4; power distribution panels in Units 2 and 4 are connected to offsite power. Work continues on energizing equipment in Unit 2 and Unit 4.

Protective Measures Team (PMT) Update

The PMT continues to aggregate and assess available dose rate information from DOE Aerial Monitoring operations, the U.S. Navy, and TEPCO. Multi-day trending of available onsite monitors shows slightly declining dose rates over the past several days. Based upon information received on March 25 and 26, dose rates at the main gate were 16 mR/hr (Source: MEXT). This shows a slight trend downward.

Potential ingestion pathway radiation measurements made by the Japanese government on food from regions near the Daiichi site exceed the values established by the U.S. Food and Drug Administration (FDA). According to the Ministry of Economy, Trade, and Industry (METI) on March 26, the governors of Fukushima, Ibaraki, Tochigi, and Gunma Prefectures have been directed to issue suspension of shipment and restriction of intake for various vegetables and milk. In addition, restriction of drinking tap water (for all residents in some cases, and only for babies in others) have been issued in specific locations within Fukushima, Ibaraki, and Chiba Prefectures. (Source: METI).

The PMT has completed a draft of the recommendations for short term reentry of personnel for retrieval of personal effects and it has been sent to OSTP, DOE and the NRC team for comment by March 27, 2011.

The PMT has compiled a comprehensive list of hypothetical source terms since the onset of the crisis in Japan that have been supplied to NARAC.

The source terms are summarized in a matrix by date and reactor unit/spent fuel pool, and percent fuel melt. The PMT i trending exposure rate data around the site based on Ministry of Education, Culture, Sports, Science and Technology (MEXT) data which is periodically sent to the PMT. A downward trend can be clearly seen at monitoring points northwest of the site, in that originally exceeded the evacuation PAG.

Per IAEA 1700 UTC March 24, Radiation exposure on 3 TEPCO related workers was confirmed. They were working in the basement Unit 3 turbine building where contaminated water was on the floor. The radiation exposures of the 3 workers were 180 mSv, 179 mSv, and 173 mSv. Additional information received on March 26 by METI and two workers were evaluated for possible beta burns to the legs. The evaluation concluded that the workers received a possible beta dose between 200 – 600 Rem, and concluded that treatment was unnecessary but progress will be monitored.

PMT has completed work with NARAC on the source term for Plausible Realistic Case model based on plant conditions as of March 24, 2011. Run was completed at 1400 EDT on March 25, 2011, and results have been verified by the PMT. The Plausible Realistic Case assumed partial melting of Unit 1 (70% core melt; 10%/day release), Unit 2 (33% core melt; a 5-inch sq. hole in containment), and Unit 3 (33% core melt; 100%/day release). The case did not assume any release from the spent fuel pools. Actual meteorological data and forecasts were used.

Releases were assumed to occur over 12 days, and dose results were calculated for 14 days for locations in Japan.

According to the RASCAL run using this source term, TEDE was greater than 5 rem out to around 2 miles and greater than 1 rem (TEDE PAG) out to around 8 miles
from the plant. Adult thyroid dose was greater than 10 rem out to around 5.25 miles from the plant. Child thyroid dose was greater than 5 rem out to around 11 miles from the plant. PMT completed a requested breakdown of release assumptions by each unit, and the assumed core inventories for Dr. Holdren, OSTP. The source term used from RASCAL was questioned by the White House; the PMT has re-evaluated and determined that RASCAL results are accurate based on scenaro assumptions.


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