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The measurement situation of radiological density, air dose in Resources and Waste Recycling Bureau

  The measurement situation of radiological density, air dose in garbage destruction by fire factory and landfill

  The air dose measurement (the Mike Rothe pot investigation) at use of citizen point

  The measurement situation of the radiological density of green compost

  ・Radiological concentration measurement situation nitsu of activated carbon of deodorant device of resources sorting center and broadcast transportation officeBe

  The measurement situation of radiological density in industrial waste incineration facilities

 

 

The measurement situation of radiological density, air dose in garbage destruction by fire factory and landfill

◆Radiation measures◆

  In Yokohama-shi, we perform radiation measures in Minamihonmoku landfill and destruction by fire factory.
  As for the details, please see this.


◆Result of a measurement◆

 In Yokohama-shi, we investigate radioactive materials levels such as destruction by fire ash occurring in four garbage destruction by fire factories operating now in the city and flow death by drowning of landfill, discharge water.
In addition, air dose investigates destruction by fire factory (site border, hihaitokorisakugyojoshofukin) and landfill (site border, the neighborhood of inning work place).

 It continues and investigates and confirms safety and will announce result of a measurement in future on homepage.

・Garbage destruction by fire factory
 
Tsuzuki factory / Tsurumi factory / Asahi factory / Kanazawa factory
 
 The radiological density of destruction by fire ash which occurred in garbage destruction by fire factory is less than inning standard 8,000Bq/kg which country showed.
In addition, it is "the non-detection" about radioactive material concentration in effluent gas and can prevent discharge by effluent gas processing equipment.
 Air dose such as site borders of garbage destruction by fire factory is at the same level as result of a measurement of other points in the city.
               
・Landfill
 
Minamihonmoku landfill / Shinmeidai disposal place
 
  All the circumference of Minamihonmoku landfill is kept by building a breakwater with impermeable function, and it is in structure that inland waters of disposal ground leak, and does not appear.
In addition, radioactive material is not detected from inflow water and discharge water in drainage handling of Minamihonmoku landfill facility to treat inland waters appropriately.
  We will push forward conduct of measures as much as possible in future in drainage processing facility to make sure of radiation measures.
  Air dose such as site borders of landfill is equal to result of a measurement of other points in the city.

 

◆Method for measurement◆

    1. Radiological density 
      (1) Sampling method
      A destruction by fire ash and drainage sludge
        "Radioactivity concentration is based in method for measurement guidelines" (Ministry of the Environment, March, 2013)
     
  • Destruction by fire ash: We gather using scoops and dispense in sample container (polybottle) after mixture.
  • Drainage sludge: We gather in sample container (polybottle) using saideiki.
     

 

      i drainage and water of public area of the sea
        "Radioactivity concentration is based in method for measurement guidelines" (Ministry of the Environment, March, 2013)
        We collect water in sample container (polybottle) using ladle, bucket.
       
      u effluent gas
        We are based based on JIS Z8808 on "radioactivity investigation, assay tentativeness manuals such as refuse" (National Institute for Environmental Studies others, November 11, 2011)
           Sampling device which aspirates equal speed from existing "baijin" established in chimney flue wall surface measurement hole, and is comprised of cylinder filter paper, liquid sampling department (in pin jar) and activated carbon
        We gather niyori.
       
     
Effluent gas sampling device
       
      (2) Method for measurement
          According to August, 1992 (3 *) Ministry of Education, Culture, Sports, Science and Technology radioactivity assay series No. 7 "gamma beam spectrometry with germanium semiconductor detector,"
         We measure using germanium semiconductor detector.
       
    2. Air dose
      (1) Method for measurement
        "Radioactivity concentration is based in method for measurement guidelines" (Ministry of the Environment, December, 2011)
     
  • Garbage destruction by fire factory: We measure at seven spots, 1m above the ground of site border and hihaitokorisakugyojoshoto in total
  • Minamihonmoku landfill: We measure at nine spots, 1m above the ground of site border and inning place in total
  • Shinmeidai disposal place: We measure at five spots, 1m above the ground such as site borders in total (in addition, we measure at 1m above the ground and 0.5m in use of citizen facility three spots)
     

 

      (2) Measuring equipment
         NaI(TI) scintillation survey meter TCS-172B made in Hitachi Aloka Medical Corporation
         (measurement range: 0.01-30μSv/h)
       
     

   [from July, 2011 to November]

          Advanced GM survey meter ASM-990 made in FLUKE-Biomedical company
         (measurement range: 0.01-800μSv/h)
     

  

     <remarks>
   

 

・ Unevenness comes out to measurements even if we measured the same radiation dose by the measurement of radiation dose with survey meter.

     

  In addition, measurements of radiation change by wind or the rain even if they receive influence with geological feature of measurement point or neighboring buildings and measure at the same place.

 

◆Press release documents◆

 ・

About result of a measurement such as radioactivity concentration to affect garbage destruction by fire factory of Motoichi and landfill (PDF: 184KB)

 ・

About inning of sewage sludge destruction by fire ash (to Environmental Planning Bureau homepage)

  

The air dose measurement (the Mike Rothe pot investigation) at use of citizen point

   To confirm existence yes or no of "microspot" about point that citizen uses by visits in facility which Resources and Waste Recycling Bureau has jurisdiction over,
  We carry out the measurement of air dose.

Result of a measurement◆
   ・ List of air dose measurement (the Mike Rothe pot investigation) results at citizen's use point in Resources and Waste Recycling Bureau jurisdiction facility
◆Press release documents◆
    About result of a measurement of radiation dose in Resources and Waste Recycling Bureau jurisdiction facility (PDF: 163KB)
 

The measurement situation of the radiological density of green compost

   Result of a measurement to page of wastes measures section

 

About the radiological concentration measurement situation of activated carbon of deodorant device of resources sorting center and broadcast transportation office

   Result of a measurement to page of Operations Section

 

The measurement situation of radiological density in industrial waste incineration facilities

   Result of a measurement to page of industrial waste measures section