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- Specific Hazardous Substances and Designated Criteria
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Specific Hazardous Substances and Designated Criteria
Last Updated April 2, 2024
The Soil Contamination Countermeasures Act (hereinafter referred to as the "Law") sets standards for soil contamination for 26 types of specified hazardous substances.
In addition, the Ordinance on the conservation, etc. of Yokohama City Living Environment (hereinafter referred to as the “Ordinance”) sets standards for soil contamination for dioxins in addition to specified hazardous substances stipulated in the law.
- Specific Hazardous Substances and Designated Criteria
- Standards for dioxins (only applicable to ordinances)
Specific hazardous substances
Class 1 Specific Hazardous Substances (volatile organic compounds)
Chloroethylene, carbon tetrachloroethylene, 1,2-dichloroethylene, 1,1-dichloroethylene, 1,2-dichloroethylene, 1,3-dichloropropenne, dichloromethane, tetrachloroethylene, 1,1,1-trichloroethylene, 1,1,2-trichloroethylene, 1,trichloroethylene
About decomposed products
For Class 1 specific hazardous substances, decomposition products corresponding to specific hazardous substances are defined as follows. If a parent substance is used, the decomposition product of that substance is also subject to investigation.
| Parent substance | Breakdown products (Specific Hazardous Substances) | Remarks |
|---|---|---|
| Carbon tetrachloride | Dichloromethane | From April 1, 2019, the decomposition generation route will be added. |
| 1,1-dichloroethylene | Chloroethylene | No, no |
| 1,2-dichloroethylene | Chloroethylene | No, no |
| Tetrachloroethylene | Chloroethylene, 1,1-dichloroethylene, 1,2-dichloroethylene, trichloroethylene | No, no |
| 1,1,1-trichloroethane | Chloroethylene, 1,1-dichloroethylene | No, no |
| 1,1,2-trichloroethane | Chloroethylene, 1,2-dichloroethane, 1,1-dichloroethylene, 1,2-dichloroethylene | No, no |
| Trichloroethylene | Chloroethylene, 1,1-dichloroethylene, 1,2-dichloroethylene | No, no |
| Chloroform | Dichloromethane | Although chloroform is not a specific hazardous substance, dichloromethane, a decomposition product, is a specific hazardous substance. |
Decomposition generation route
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, fluorine and its compounds, boron and its compounds, 9 substances
Class 3 Specified Hazardous Substances (pesticides, etc.)
Simidine, thiobencarb, thylum, polychlorinated biphenyl (PCB), and organic phosphorus compounds
Standards for Designation of Laws and Ordinances
If it exceeds the soil content standard or soil elution standard, it is designated as an area based on laws or regulations.
Soil content standards
Soil content standards are established from the viewpoint of the health effects of direct intake of contaminated soil.
Standard for Soil Elution
Soil elution standards are determined from the viewpoint of health effects of ingestion via groundwater.
Second elute volume standard
The second elution quantity standard is determined from the viewpoint of selecting countermeasures or determining decisions.
Groundwater standards
Groundwater standards are used in groundwater monitoring after measures in (regulations) areas requiring measures, such as when judging whether or not the designation of (regulations) requiring action areas can be canceled.
※Regarding guidance for persons responsible for groundwater contamination based on Article 61-2 of the Ordinance, groundwater purification standards are separately stipulated in the ordinance.
| Specific hazardous substances | Soil content standards | Standard for Soil Elution | Second elute volume standard | Groundwater standards | Remarks |
|---|---|---|---|---|---|
| Chloroethylene | No, no | 0.002 or less | 0.02 or less | 0.002 or less | Added on April 1, 2017 |
| Carbon tetrachloride | No, no | 0.002 or less | 0.02 or less | 0.002 or less | There are specific hazardous substances in decomposed products |
| 1,2-dichloroethane | No, no | 0.004 or less | 0.04 or less | 0.004 or less | No, no |
| 1,1-dichloroethylene | No, no | 0.1 or less | 1 or less | 0.1 or less | ・There are specific hazardous substances in decomposed products |
| 1,2-dichloroethylene | No, no | 0.04 or less | 0.4 or less | 0.04 or less | ・There are specific hazardous substances in decomposed products |
| 1,3-dichloropropene | No, no | 0.002 or less | 0.02 or less | 0.002 or less | No, no |
| Dichloromethane | No, no | 0.02 or less | 0.2 or less | 0.02 or less | No, no |
| Tetrachloroethylene | No, no | 0.01 or less | 0.1 or less | 0.01 or less | There are specific hazardous substances in decomposed products |
| 1,1,1-trichloroethane | No, no | 1 or less | 3 or less | 1 or less | There are specific hazardous substances in decomposed products |
| 1,1,2-trichloroethane | No, no | 0.006 or less | 0.06 or less | 0.006 or less | There are specific hazardous substances in decomposed products |
| Trichloroethylene (*) | No, no | 0.01 or less | 0.1 or less | 0.01 or less | ・There are specific hazardous substances in decomposed products |
| Benzene | No, no | 0.01 or less | 0.1 or less | 0.01 or less | No, no |
| Cadmium and its compounds(*) | 45 or less | 0.003 or less | 0.09 or less | 0.003 or less | Changed 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 | No, no |
| Cyanide compounds | 50 or less As a free cyan | Not detected | 1.0 or less | Not detected | No, no |
| Mercury and its compounds | 15 or less | 0.0005 or less, In addition, alkyl mercury is not detected | 0.005 or less, In addition, alkyl mercury is not detected | 0.0005 or less, In addition, alkyl mercury is not detected | No, no |
| Selenium and its compounds | 150 or less | 0.01 or less | 0.3 or less | 0.01 or less | No, no |
| Lead and its compounds | 150 or less | 0.01 or less | 0.3 or less | 0.01 or less | No, no |
| Arsenic and its compounds | 150 or less | 0.01 or less | 0.3 or less | 0.01 or less | No, no |
| Fluorine and its compounds | 4,000 or less | 0.8 or less | 24 or less | 0.8 or less | No, no |
| Boron and its compounds | 4,000 or less | 1 or less | 30 or less | 1 or less | No, no |
| Zimazine | No, no | 0.003 or less | 0.03 or less | 0.003 or less | No, no |
| Chiuram | No, no | 0.006 or less | 0.06 or less | 0.006 or less | No, no |
| Thiobencarb | No, no | 0.02 or less | 0.2 or less | 0.02 or less | No, no |
| Polychlorinated biphenyl (PCB) | No, no | Not detected | 0.003 or less | Not detected | No, no |
| Organic phosphorus compounds (paration, methylparation, methyldi Meton, and EPN) | No, no | Not detected | 1 or less | Not detected | No, no |
※As of April 1, 2021, the standards for cadmium and its compounds and trichlorethylene have been changed.
| Specific Hazardous Substances and Designated Criteria | Soil content standards | Standard for Soil Elution | Second elute volume standard | Groundwater purification standards |
|---|---|---|---|---|
| Trichloroethylene | No, no | 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 |
Inquiries to this page
Water and Soil Environment Division, Environmental Conservation Department, Yokohama City Green Environment Bureau
Telephone: 045-671-2494
Telephone: 045-671-2494
Fax: 045-671-2809
Email address: mk-dojo@city.yokohama.lg.jp
Page ID: 455-265-160
