TEPCO Fukushima Daiichi Nuclear Power Plant ALPS Treated Water Monitoring Results after Discharge into the Ocean (31 August – 16 September 2023)

Discharge of the first batch of treated water (7788 m3) was completed on 11 September.

●TEPCO
On 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, and 6 September, the monitoring results of tritium concentration in seawater collected from 10 locations within 3km of the Fukushima Daiichi nuclear power plant confirmed that tritium concentration was below the lower limit of detection at all monitoring points.
 
On 13, 12, 11, 6 September and 30 August, the monitoring results of tritium concentration in seawater collected from one site within 10 km of the Fukushima Daiichi Nuclear Power Plant confirmed that the tritium concentration was below the lower limit of detection (below 7.2 Bq/L).
 
On 10 September, it was announced that of the four sites, the tritium concentration at the site closest to the ALPS treated water discharge outlet (200 metres from the outlet) was, and the tritium concentration at the remaining three sites (600-1,600 metres from the outlet) was below the lower limit of detection.
 
●Ministry of the Environment (Seawater)
On 5-6 September, the Ministry of the Environment confirmed that tritium concentrations were below the lower limit of detection at all monitoring points, based on the results of a rapid measurement of tritium concentrations in seawater collected at nine monitoring points in Fukushima Prefectural waters, one point in Miyagi Prefectural waters, and one point in Ibaraki Prefectural waters.
 
●Fukushima Prefecture (Seawater)
On 12 September, results of rapid measurement of tritium concentration in seawater collected at nine monitoring sites in the waters of Fukushima Prefecture confirmed that tritium concentration was below the lower limit of detection at all monitoring sites.
https://www.pref.fukushima.lg.jp/site/portal/moni-k.html
 

●Japanese Government Fisheries Agency
In the morning of 16, 15, 14, 13, 12, 11, 7, and 6 September, the results of monitoring of tritium concentration in halibut caught from 4km north of the ALPS treated water discharge point and 5km south of that discharge point confirmed that tritium concentration was below the lower detection limit at all the monitoring points.
 

The Government of Japan is conducting three types of monitoring (monitoring of treated water in tanks, real-time monitoring, and sea area monitoring) in a multilayered manner with the involvement of the IAEA. The IAEA also conducts sea area monitoring.
These monitoring results can be accessed at any time in the following websites;

1. Monitoring of treated water in tanks

TEPCO:
https://www.tepco.co.jp/en/decommission/progress/watertreatment/measurementfacility/index-e.html
 
JAEA (Third Party Monitoring) :
https://fukushima.jaea.go.jp/okuma/alps/index_e.html
 

2. Sea area monitoring

TEPCO:
https://www.tepco.co.jp/en/decommission/progress/watertreatment/monitoring/index-e.html 
 
Ministry of Environment:
https://shorisui-monitoring.env.go.jp/en/
 
Fisheries Agency :
https://www.jfa.maff.go.jp/e/inspection/index.html#rapid　
 

3. Real-time Monitoring

TEPCO :
https://www.tepco.co.jp/en/decommission/progress/watertreatment/dischargefacility/index-e.html
 
IAEA :
https://www.iaea.org/topics/response/fukushima-daiichi-nuclear-accident/fukushima-daiichi-alps-treated-water-discharge/tepco-data