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- Specified Hazardous Substances and Designated Criteria
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Specified Hazardous Substances and Designated Criteria
Last update date April 2, 2024
The Soil Contamination Countermeasures Law (hereinafter referred to as the "law") stipulates standards for soil pollution for 26 specific hazardous substances.
In addition, the ordinance on conservation, etc. in the Yokohama City Living Environment (hereinafter referred to as the “Ordinance”) stipulates standards for soil contamination for dioxins in addition to specified harmful substances prescribed by law.
- Specified Hazardous Substances and Designated Criteria
- Standards for dioxins (applicable only by ordinance)
Specified hazardous substances
Class 1 Specified Hazardous Substances (volatile Organic Compounds)
Chloroethylene, carbon tetrachloride, 1,2-dichloroethylene, 1,1-dichloroethylene, 1,2-dichloroethylene, 1,3-dichloropropen, dichloromethane, tetrachloroethylene, 1,1-trichloroethane, 1,1,2-trichloroethylene and bebenzenethylene
Decomposed products
For Class 1 Specified Hazardous Substances, decomposed products that fall under specified hazardous substances are specified as follows. If a parent substance is used, the decomposed product of that substance is also subject to investigation.
| Parent Substances | Decomposed products (specified harmful substances) | Remarks |
|---|---|---|
| Carbon tetrachloride | Dichloromethane | The decomposition and generation path has been added since April 1, 2019. |
| 1,1-dichloroethylene | Chloroethylene | Nothing |
| 1,2-dichloroethylene | Chloroethylene | Nothing |
| Tetrachloroethylene | Chloroethylene, 1,1-dichloroethylene, 1,2-dichloroethylene, trichloroethylene | Nothing |
| 1,1,1-trichloroethane | Chloroethylene, 1,1-dichloroethylene | Nothing |
| 1,1,2-trichloroethane | Chloroethylene, 1,2-dichloroethylene, 1,1-dichloroethylene, 1,2-dichloroethylene | Nothing |
| Trichloroethylene | Chloroethylene, 1,1-dichloroethylene, 1,2-dichloroethylene | Nothing |
| Chloroform | Dichloromethane | Although chloroform is not a specific harmful substance, dichloromethane, a decomposition product dichloromethane is a specified harmful substance. |
Decomposition generation path
Class 2 Specified Hazardous Substances (heavy metals, etc.)
Cadmium and its compounds, hexavalent chromium compounds, cyanide compounds, mercury and its compounds, selenium and its compounds, lead and its compounds, arsenic and its compounds, arsenic and its compounds, fluorine and its compounds, boron and its compounds, arsenic and its compounds.
Class 3 Specified Hazardous Substances (Agrochemicals, etc.)
5 substances: zemadine, thiobencarb, thyuram, polychlorinated biphenyl (PCB), and organic phosphorus compounds
Designated standards for laws and regulations
If the soil content standard or the soil elution standard is exceeded, it is specified as an area based on laws or regulations.
Soil Content Standard
Soil content standards are established from the viewpoint of the health effects of direct ingestion of contaminated soil.
Soil Elution Amount Standard
Soil elution standards are set from the viewpoint of the health effects of intake via groundwater.
Second Elution volume standard
The second elution standard is defined from the viewpoint of making a decision on the selection of countermeasures or decision.
Groundwater Standard
Groundwater standards are used in groundwater monitoring after measures in areas requiring (regulations) to determine whether or not the designation of (Ordinance) requiring action can be canceled.
※Regarding guidance for those who cause groundwater pollution based on Article 61-2 of the Ordinance, the ordinance stipulates groundwater purification standards separately.
| Specified hazardous substances | Soil Content Standard | Soil Elution Amount Standard | Second Elution volume standard | Groundwater Standard | Remarks |
|---|---|---|---|---|---|
| Chloroethylene | Nothing | 0.002 or less | 0.02 or less | 0.002 or less | Added as of April 1, 2017 |
| Carbon tetrachloride | Nothing | 0.002 or less | 0.02 or less | 0.002 or less | Decomposed products contain specific harmful substances |
| 1,2-dichloroetan | Nothing | 0.004 or less | 0.04 or less | 0.004 or less | Nothing |
| 1,1-dichloroethylene | Nothing | 0.1 or less | 1 or less | 0.1 or less | ・Decomposed products contain specific harmful substances |
| 1,2-dichloroethylene | Nothing | 0.04 or less | 0.4 or less | 0.04 or less | ・Decomposed products contain specific harmful substances |
| 1,3-dichloropropen | Nothing | 0.002 or less | 0.02 or less | 0.002 or less | Nothing |
| Dichloromethane | Nothing | 0.02 or less | 0.2 or less | 0.02 or less | Nothing |
| Tetrachloroethylene | Nothing | 0.01 or less | 0.1 or less | 0.01 or less | Decomposed products contain specific harmful substances |
| 1,1,1-trichloroethane | Nothing | 1 or less | 3 or less | 1 or less | Decomposed products contain specific harmful substances |
| 1,1,2-trichloroethane | Nothing | 0.006 or less | 0.06 or less | 0.006 or less | Decomposed products contain specific harmful substances |
| Trichloroethylene(*) | Nothing | 0.01 or less | 0.1 or less | 0.01 or less | ・Decomposed products contain specific harmful substances |
| Benzene | Nothing | 0.01 or less | 0.1 or less | 0.01 or less | Nothing |
| Cadmium and its compounds(*) | 45 or less | 0.003 or less | 0.09 or less | 0.003 or less | Changes in the standard value on April 1, 2021 |
| Hexavalent chromium compounds | 250 or less | 0.05 or less | 1.5 or less | 0.05 or less | Nothing |
| Cyanide compounds | 50 or less As a free cyan | Not detected | 1.0 or less | Not detected | Nothing |
| Mercury and its compounds | 15 or less | 0.0005 or less; In addition, alkyl water silver is not detected | 0.005 or less; In addition, alkyl water silver is not detected | 0.0005 or less; In addition, alkyl water silver is not detected | Nothing |
| Selenium and its compounds | 150 or less | 0.01 or less | 0.3 or less | 0.01 or less | Nothing |
| Lead and its compounds | 150 or less | 0.01 or less | 0.3 or less | 0.01 or less | Nothing |
| Arsenic and its compounds | 150 or less | 0.01 or less | 0.3 or less | 0.01 or less | Nothing |
| Fluorine and its compounds | 4000 or less | 0.8 or less | 24 or less | 0.8 or less | Nothing |
| Boron and its compounds | 4000 or less | 1 or less | 30 or less | 1 or less | Nothing |
| Zemadine | Nothing | 0.003 or less | 0.03 or less | 0.003 or less | Nothing |
| Tiuram | Nothing | 0.006 or less | 0.06 or less | 0.006 or less | Nothing |
| Thiobencarb | Nothing | 0.02 or less | 0.2 or less | 0.02 or less | Nothing |
| Polychlorinated biphenyl (PCB) | Nothing | Not detected | 0.003 or less | Not detected | Nothing |
| Organic phosphorus compounds (parathion, methylparation, methyldi Meton, and EPN) | Nothing | Not detected | 1 or less | Not detected | Nothing |
※Effective April 1, 2021, the standards for cadmium, its compounds, and trichloroethylene have been changed.
| Specified Hazardous Substances and Designated Criteria | Soil Content Standard | Soil Elution Amount Standard | Second Elution volume standard | Groundwater purification standards |
|---|---|---|---|---|
| Trichloroethylene | Nothing | 0.03 or less | 0.3 or less | 0.03 or less |
| Cadmium and its compounds | 150 or less | 0.01 or less | 0.3 or less | 0.01 or less |
| Items | Standards for Soil Contamination | Groundwater purification standards |
|---|---|---|
| Dioxins | 1,000 or less | 1 or less |
For inquiries to this page
Yokohama City Green Environment Bureau Environmental Conservation Department Water and Soil Environment Division
Phone: 045-671-2494
Phone: 045-671-2494
Fax: 045-671-2809
Email address: mk-dojo@city.yokohama.lg.jp
Page ID: 455-265-160
