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Reality check on fire pumps providing cooling water, NISA update, pp II-83: "Since all AC power was lost and emergency cooling system became unavailable due to tsunami, TEPCO worked for cooling the reactor with alternative water injection. The staff were forced to work under the severe environment where the major tsunami warning continued, evacuation and work were interrupted, there were no tools for lightening and communicating, and the debris and dirt were stranded by tsunami. The response status is described as follows in a chronological order.
17:12, March 11, TEPCO started to take into consideration using alternative water injection measure set as AM actions (fire protection system, FP) , make-up water condensate system (MUWC) and fire engines using fire cistern set up as a lesson from the Chuetsu-oki Earthquake.
In the main control room, in order to confirm the alternative water injection measures, the AM operational procedure was submitted to the shift supervisor, alternative water injection lines to reactors were confirmed, the preparation for activating diesel-driven fire pump have been started.
Regarding water injection to reactors, in order to develop alternative water injection line via the core spray system (CS) from FP line, staff entered the reactor buildings in the dark, manually opened valves of CS, etc, then after the depressurization of reactor pressure (less than 0.69MPa gage), made the condition available for water injection.
At 17:30, March 11, the diesel-driven fire pump was confirmed to be in a workable condition. Since the indicated value of the supervisory instrumentation in the main control room was invisible, the staff entered into the reactor building and confirmed that the pressure gauge indicated 6.9MPa gage (20:07, March 11). After that, the water-level gauge was restored at 21:19 on the same day, confirming the indication of TAF+200mm.
At 01:48, March 12, staff confirmed that the diesel-driven fire pump which had been in operation for injecting water to the reactor stopped at some point, thus they carried and supplemented light oil manually, carried batteries kept in cooperative firms on the site for replacement, etc, but could not restart the operation.
In order to start injecting water as soon as possible, preparation for injection of water via fire engines was implemented along with restoration of diesel-driven fire pump. One of three fire engines deployed in the NPS was used. Second one was broken down due to tsunami, and the third one was not usable as it could not be transferred from the side of Units 5 and 6. There were also many obstacles in deployment of the usable one. The road in front of the former main office building was not trafficable as it was blocked with a tank drifted by tsunami. As the gate of the security office could not be opened with any electricity, after thorough search for trafficable routes, they made the fire engine pass through by breaking a key of the locked gate located between Units 2 and 3.
The fire hydrant which should have been used for the water source was not usable as water spewed out from it, thus search for other water sources was implemented. As a result of it, fire cistern was confirmed to be usable.
At 02:45, March 12, it was found that the reactor pressure was 0.8MPa gage, meaning depressurization proceeded to the level enabling the injection of water via fire engine. At 05:45, March 12, injection of fresh water via fire engine from FP line was started.
As for the initial injection of water, the discharge pressure was considered to be insufficient from the position of the fire cistern, thus the series of work such as transferring water from the fire cistern to the tank of fire engine, the relocation of fire engine closer to the rector building, and injection of water from the water discharge canal of FP to the reactor, was repeatedly implemented.
The relocation of the fire engine, however, took long time as it needed to cautiously pass under the crumbling building. Therefore, as a result of try-and-error, with the development of continuous water injection line using the hoses attached to fire engine, continuous injection of water started.
With the arrival of a fire engine which was additionally arranged, transfer of fresh water from the fire cistern of Unit 3 to that of Unit 1 was repeatedly implemented. Since the fire cistern could accommodate only one hose, in case of fresh water feed, the hose for injecting water to the rector needed to be taken out, accordingly the water injection work were forced to be suspended each and every time. At 14:53, March 12, 80,000l (accumulated total) of fresh water injection was completed.
While fresh water injection was continued, since securing fresh water in the fire cistern had limitation, preparation for seawater injection was implemented.
At 14:54, March 12, the plant manager instructed to prepare for injecting seawater to the reactor. Since the fresh water in the fire cistern was depleted, quick transfer of fresh water from other fire cisterns as well as preparation for switching to seawater injection were implemented. For the injection of seawater, judging from the road condition on the site and the distance to Unit 1, backwash valve pit, which accumulated seawater due to tsunami, was set as water source rather than taking water directly from the sea, and in order to ensure lifting height, water injection line with three fire engines arranged in tandem was completed.
As for SLC, another alternative water injection measure, since the early dawn on March 12, work including laying of temporary cables to transfer power from power supply vehicle via power distribution panel of Unit 2 etc, was implemented, and around 15:30, March 12, cable connections inside the building to the primary side of power center (P/C) and connection with a high-pressure power supply vehicle were completed, then power was transmitted to just beside the SLC pump.
In the meantime, at 15:36, March 12, an explosion occurred in the reactor building of Unit 1.Evacuation from the site, aid and transfer of the injured due to the explosion were executed. The number of the injured of TEPCO was three, and that of the cooperative firms was two. Following this, in order to ensure safety, on-site inspection to study the effect of the explosion (condition of fire engines, damage situation of the building, situation of smoking ) was implemented. Windows of fire engines were broken, but the function was not damaged. Cable laid for operating SLC was damaged due to splattered debris, the high pressure power supply vehicle was automatically suspended. In addition, hoses which had been prepared for seawater injection were also damaged.
Until the evacuation from the site and safety check of the staff were executed and the situation of the site was confirmed, nothing could be done for restoration for some time.
Since highly radioactive debris were scattered around Unit 1, under the supervision of radiation control staff, work such as removing the scattered debris (steel panel of the reactor building of Unit 1, etc) and collecting hoses from yard fire hydrants for rebuilding, was implemented.
Finally, at 19:04, May 12, injection of seawater into the reactor using FP lines and fire engines was started." So much for fire engine drills!

hi, dean and edano. As you can see, this drill is a pr show.