Commentary on the economic , geopolitical and simply fascinating things going on. Served occasionally with a side of snark.
Sunday, March 16, 2014
Fukushima nuclear debacle - Weekly thread for the week commencing March 16 , 2014 -- two common themes so far -- radioactive contamination has been steadily increasing ( Tritium density in groundwater has been increasing upstream of groundwater bypass wells , All β nuclide (including Strontium-90) density in groundwater has been increasing since this December on the seaside of reactor2 and 3. ) And the facility is falling apart slowly in front of the world's eyes ( Rain water leak into reactor1 building through the crippled roof, Tepco announced on 3/14/2014 . Tepco to shield reactor1 pool coolant system against the damaged stack / Stopping cooling the pool for 11 days . )
Following up this article.. Multiple nuclide removing system practically in a shutdown state / Not purifying All β nuclides [URL]
The broken multiple nuclide system ALPS (Advanced Liquid Processing System) had already “processed” 2,500 tonnes of contaminated water, according to Tepco.
The water still contains 10,000,000,000 Bq/m3 of All β nuclides, which is 100,000 times much as the design value. Tepco announced the main contamination would be Strontium-90.
The cause of the trouble hasn’t been identified, but the “processed” water remains still highly radioactive. This 2,500 tonnes of contaminated water was already transferred to 21 tanks. These tanks were supposed to stock relatively clean water.
The capacity of each tank is 1,000 tonnes. Those 21 tanks were 70% full and connected to each other when Tepco noticed the system problem of ALPS. They haven’t investigated how much the contamination spread among those tanks to ruin their own water storage strategy.
Following up this article.. [ALPS shut-down] Tepco has already transferred 2,500 t of unpurified water to 21 clean tanks [URL]
21 tanks and 1km long pipes need to be entirely decontaminated due to the system failure of multiple nuclide system ALPS (Advanced Liquid Processing System).
ALPS is one of the two major countermeasures for contaminated water along with frozen water wall. Tepco plans to process 1,960 tonnes of contaminated water by ALPS on the daily basis, but it hasn’t been in the full operation only to process less than half of the planned volume.
Before they noticed the system didn’t purify the water, they had already transferred the unpurified water to 21 of 1,000t tanks. Tepco is still planning to use these tanks to stocked clean water after ALPS processing, so they need to decontaminate the tanks and 1km long pipe.
They still don’t know when they complete the decontamination, but ALPS will be suspended until they complete.
Following up this article.. Groundwater in deep layer possibly traveling between sea and land / Tepco not to investigate it anymore [URL]
On 3/19/2014, Tepco clearly rejected to investigate the possibility that contaminated groundwater and seawater are seamlessly moving underground of Fukushima plant.
From Tepco’s data, groundwater level is synced with ebb and flow in deep boring holes. However they abandoned them and decided to use only shallow boring holes, which don’t show the groundwater level trend.
In the press conference of 3/19/2014, a freelance journalist injured what the reason is not to test chloride concentration of groundwater. Only if they measure the chloride concentration, they can prove if seawater is coming to the underground of Fukushima plant.
Tepco’s spokesman stated they will not test chloride concentration, and the reason wasn’t announced.
Following up this article.. Another system of ALPS suspended again / Only one week since last suspension [URL]
On 3/18/2014, Tepco suspended the entire system of multiple nuclide removing system, ALPS (Advanced Liquid Processing System).
One of the systems called “B” didn’t purify the contaminated water. From the “processed” water taken on 3/17/2014, they measured 10,000,000,000 Bq/m3 of All β nuclides to include Strontium-90. This is 100,000 times much as the usual reading. The system “B” was under maintenance, but Tepco suspended 2 of the other systems too, which means the entire system is practically in the shutdown state.
Following up this article.. Groundwater level found sync with ebb and flow of the sea → Tepco to abandon the measuring point, “Not credible data” [URL]
Groundwater may be already moving between sea and the land freely in the deep layer, and the contamination is flowing to the Pacific.
In the press conference of 3/17/2014, it turned out that the groundwater level synced with ebb and flow was observed 16m underground. Tepco stated the data doesn’t have adequate credibility because other boring points don’t show the groundwater levels synced, and decided to abandon the issued boring point. However, other boring points are only 5m underground. The gap of the depths haven’t been cleared until then. Additionally, these boring points are only 2m from each other.
There is the possibility that the groundwater and seawater are seamlessly traveling deep underground to convey the highly contaminated water to the sea.
Tepco stated they won’t investigate it anymore, and the reason wasn’t announced either.
Debris removal from reactor3 pool is in 4 months delay, Tepco reported to NRA (Nuclear Regulation Authority) this February.
Tepco is in the process to remove debris from around the spent fuel pool of reactor3.
However due to the extremely high level of radiation, it is being behind the schedule.
In the press conference of 3/17/2014, Tepco stated it may be because they suspended the removal when they found the workers severely contaminated possibly due to the emission from reactor3, where is over 500m away from the workers. They also stopped removing when they observed the “steam” coming up from the top of the building last summer. They also had to stop operation when the crane was significantly damaged, which the reason has not been identified yet.
Related to this article.. Underground wall on the seaside of reactor3 was possibly broken / Groundwater level in sync with ebb and flow [URL]
All β nuclide (including Strontium-90) density in groundwater has been increasing since this December on the seaside of reactor2 and 3.
It went up to over 10 times much within 3 months, according to Tepco. However the sampling location is outside of the underground wall, which Tepco completed the construction by December. The location therefore is separated from the reactor buildings, but facing the sea.
At another sampling location inside of the wall, All β nuclide density has not been increasing from Tepco’s data. There is no explainable path of contamination but it rose up from underground deeper than the underground wall.
Regarding this trend, Tepco hasn’t made any announcement.
Rain water leak into reactor1 building through the crippled roof, Tepco announced on 3/14/2014.
Fukushima decommissioning takes more 40 years according to the government of Japan. Rain leaking is deteriorating the reactor building every time it rains.
On 3/14/2014, Tepco employee found rain water retained in 2m × 10m on the first floor of reactor1 building. They measured 66,000,000 Bq/m3 of Cesium-134/137 from the water, but assumed it not to be the direct leakage of coolant water because the density is 152 times higher than 66,000,000 Bq/m3.
Tepco announces there was a rain one day before, and it’s still leaking into the building through the roof at 5m width. Due to the high level of radiation, they cannot repair the crippled part of the building.
Following up this article.. 1.9 mSv/h detected at 54 m above ground along the damaged stack[URL]
Tepco is going to install covers over the facilities to protect against the damaged stack. The stack is 120m tall and have the damages at 66m height from the ground. Even a bolt would cause a significant damage by falling to the neighboring facilities.
The coolant system of reactor1 spent fuel pool will be suspended for 11 days from 3/14/2014 due to the installation.
The stack has 8 damages and 5 parts are cut off, however Tepco cannot dismantle it. It is not known how to dismantle the stack either.
Related article.. [Damaged stack] Tepco “looking for” the way to dismantle / cover the stack for high level of radiation [URL 2]