Revised information (Water Pollution Control Law, Ordinance on conservation, etc. of Yokohama City Living Environment (Water Quality))

Revisions to the Water Pollution Control Law and the Ordinance on conservation, etc. of the Yokohama City Living Environment since 2022 are posted.

In January 2024, the Water Pollution Control Law Enforcement Ordinance was revised, and drainage standards were revised as follows.

1. Change of effluent standards for hexavalent chromium compounds

• From April 1, 2024, the drainage standard will be 0.2 mg / L.
• The application of existing specified business establishments will be deferred until September 30, 2024. Existing specific business sites such as test and research institutions that have cleaning facilities, etc.Water Pollution Control Law Enforcement Order (outside site)Business establishments that set up the facilities listed in Appendix 3) will be deferred until March 31, 2025.
• The provisional drainage standard of 0.5 mg / L will be applied to specific business sites of the electric plating industry until March 31, 2027.

2. Change of items in fecal contamination indicator

• From April 1, 2025, the fecal contamination index of effluent will be changed from the number of Escherichia coliforms to the number of Escherichia colis.
• What is the measurement method?Ministerial ordinance (outside site) on verification method of sewage water qualityPlease take a look at it.

3. Change of purification standards related to orders for measures related to purification of groundwater quality

• From April 1, 2024, the purification standard will be 0.02 mg / L.

With regard to nitrogen and phosphorus in the sea area, provisional drainage standards (hereinafter referred to as “provisional drainage standards”) have been set in Paragraph 2 of the Supplementary Provisions of the Ministerial Ordinance, which stipulates drainage standards, and the application period has ended on September 30, 2023. Regarding the industries subject to the current provisional drainage standard, in light of the current actual drainage concentration of each target industry and applicable treatment technology, etc., the drainage standard (general drainage standard) prescribed in Article 1 of the Ministerial Ordinance that stipulates drainage standards The application period was extended to September 30, 2028 after confirming the feasibility of responding, reviewing the provisional drainage standards for each target industry as necessary.

On February 1, 2023, a Cabinet Order amending a part of the Water Pollution Control Law Enforcement Order was enforced, and designated substances (a large amount of waste is discharged into public water bodies causing damage to human health or living environment). The following four substances have been added to substances that may occur).

• Anilin
• Perfluorocttanic acid (PFOA) and its salt
• Perfluoro (octan-1-sulfonic acid) (PFOS) and its salt
• Direct-chain alkylbenzenesulfonic acid and its salt

For boron and its compounds (hereinafter "boron"), fluorine and its compounds (hereinafter "fluorine") and ammonia, ammonium compounds, nitrite compounds, and nitrate compounds (hereinafter "nitrate nitrogen, etc."), provisional drainage standards have been set in Paragraph 2 of the Supplementary Provisions of the Ministerial Ordinance, which partially revises the ministerial ordinance that stipulates drainage standards (hereinafter "temporary drainage standards 20"), the provisional drainage standards 20"). For 10 of the industries (11 industries) subject to the provisional drainage standard for boron, fluorine, nitrate nitrogen, etc., the Ministerial Ordinance stipulates drainage standards in light of the current situation of each industry and applicable treatment technologies. After confirming whether it is possible to comply with the drainage standards (general drainage standards) prescribed in Article 1, as shown in the table, the period of the provisional drainage standards has been extended while some standard values have been extended.

※Certain conditions are those with a value calculated by ΣCi / Qi / Q exceeds 10 (Ci: The normal concentration of wastewater (mg / L), Qi: Normal amount of wastewater from a specific business site (Sewerage Law) of the inn business that uses hot springs discharged into the sewerage system (Sewerage Law) normal amount of wastewater discharged to the sewerage system (Q3 / day), m

In March 2024, we revised a part of the ordinance enforcement regulations concerning conservation, etc. of the living environment of Yokohama City, and revised the regulations for drainage as follows.

1. Change of regulatory standards for wastewater of hexavalent chromium compounds

• From April 1, 2024, the regulatory standard will be 0.2 mg / L.
• The application of existing offices will be deferred until September 30, 2024. Existing facilities such as testing and research institutions that have installed cleaning facilities, etc.Water Pollution Control Law Enforcement Order (outside site)The application of establishments that set up the facilities listed in Appendix 3) will be deferred until March 31, 2025.
• Electric plating business establishments will be subject to the provisional regulatory standard of 0.5 mg / L until March 31, 2027.

2. Change of items in fecal contamination index

• From April 1, 2025, the fecal contamination index of wastewater will be changed from the number of Escherichia coliforms to the number of Escherichia colis.
• What is the measurement method?Ministerial ordinance (outside site) on verification method of sewage water qualityPlease take a look at it.

3. Change of groundwater purification standards related to orders for measures related to the purification of groundwater quality

• From April 1, 2024, the groundwater purification standard will be 0.02 mg / L.

On May 2, 2023, a part of the Ordinance for Enforcement of the Ordinance on conservation, etc. of the Living Environment of Yokohama City was revised, and substances related to emergency measures (air pollution, odor or water pollution caused by accidents that occurred at business sites or vehicle accidents) were added to substances related to water pollution.

• Anilin
• Perfluorocttanic acid (PFOA) and its salt
• Perfluoro (octan-1-sulfonic acid) (PFOS) and its salt
• Direct-chain alkylbenzenesulfonic acid and its salt

The Ordinance on the conservation, etc. of Yokohama City Living Environment stipulates regulatory standards (general standards) for the prevention of water pollution and applies them to all business sites in Yokohama City. However, provisional standards are applied to business sites in industries where it is difficult to immediately achieve regulatory standards.
Recently, the provisional standards for "boron and its compounds" and "fluorine and its compounds" for establishments that use hot springs have reached the application deadline on June 30, 2022, and the general standards have been applied from July 1. Was.