Press Release

December 12, 2019
  • Waste & Recycling

Monitoring Results of Air Dose Rates in and around J-Village

  1. Measures against hot spots found in the vicinity of a town-owned parking lot nearby J-village

    ・On November 18, MOE was informed by the Greenpeace Japan, an international environmental NGO, that it was confirmed that there were hot spots showing air dose rates higher than their surrounding areas around National Training Center J-village (Hereinafter J-village).

    ・Subsequently, MOE conducted a simple monitoring and found one hot spot outside a parking lot owned by Naraha Town nearby J-village where people usually do not enter.

    ・After further detailed monitoring and consultation among related organization and municipalities for implementing necessary measures, on December 3, Tokyo Electric Power Company (TEPCO), which decontaminated the parking lot before, implemented radiation reduction measures. As the result, it was confirmed that the air dose rate on the spot decreased.

Table 1: Monitoring results of the air dose rates on one hot spot outside the parking lot owned by Naraha Town

Height from the ground

Before the radiation reduction measures

(November 29)

After the radiation reduction measures

(December 3)

1m

1.79 μSv/h

0.39 μSv/h

1cm

70.2 μSv/h

0.44 μSv/h

・As the result of additional monitoring conducted around the parking lot, on December 5, relatively high air dose rate was confirmed at a spot outside the parking lot where people usually do not enter.

・On December 9, TEPCO, which decontaminated the parking lot before, implemented radiation reduction measures. As the result, it was confirmed that the air dose rate on the spot decreased.

Table 2: Monitoring results of the air dose rates on the other hot spot outside the parking lot owned by Naraha Town

Height from the ground

Before the radiation reduction measures

(December 5)

After the radiation reduction measures

(December 9)

1m

1.50 μSv/h

0.28μSv/h

1cm

10.5 μSv/h

0.28μSv/h

2. Other results of monitoring survey of air dose rates in and around J-village

・As for the football pitch and the stadium of J-village, TEPCO conducted monitoring of air dose rates on November 19 and 26 based on the request from J-VILLAGE Inc.

・Furthermore, from December 4 to 6, monitoring of air dose rates was conducted at the periphery of above mentioned facilities and the periphery of roads and facilities around J-village.

・The monitoring results of air dose rates 1m above from the ground in the football pitch, the stadium and related facilities in November were 0.04-0.17μSv/h. (0.07μSv/h in average)

・The monitoring results of air dose rates 1m above from the ground in and around J-village in December were 0.04-0.50μSv/h. (The average is 0.13μSv/h which is as same as the air dose rates of near monitoring posts)

Table 3: Other results of monitoring survey of air dose rates in and around

J-village (outline)

Monitoring results of the air dose rate

(Ref.)air dose rates of monitoring posts in surroundings

In the football pitch and the stadium of J-village

(November 19 and 26)

Around J-village*1

(December 4-6)

J-village

(Naraha)

Entrance of

J-village stadium (Hirono)

Fixed point monitoring*2

Gait monitoring*3

Gait monitoring*3

※As of 9:50 am

December 10, 2019

Number of monitoring points

72

7,384

8,309

Air dose rate 1m above from the ground

(μSv/h)

0.05-0.09 (0.07)*4

0.04-0.17 (0.07)*4

0.04-0.50*5

(0.129)*4

0.118

0.104

*1 Surroundings of the pitch and stadium of J-village and surroundings of roads and facilities around J-village

*2 Fixed point monitoring: monitored by NaI scintillation survey meter at the height above 1m from the

ground

*3 Gait monitoring: monitored by gait monitoring system at the height above 1m from the ground

*4 Average from minimum to maximum value

*5 Maximum value of 0.50 μSv/h is the air dose rate measured 1m above the ground around the area confirmed as 1.50μSv/h before TEPCO took the radiation reduction measures.

Note: 3.8 μSv/h: air dose rate reference for lifting evacuation order (less than 20 mSv of annual exposure dose)

Note: Refer to air dose rates in other major cities in the world is as follows:

Source: https://www.env.go.jp/chemi/rhm/h30kisoshiryo/h30kiso-02-05-07.html

3. Future Response

・Necessary measures will be taken and information will be shared with the public under the cooperation of related organizations if an increase of the air dose rate is confirmed at areas where decontamination work is conducted.

For Japanese

Attached File:

Get Adobe Reader

Please download Adobe Reader (for free) to view PDF file.