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- Following Survey of Contaminated Wells in FY2020
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Following Survey of Contaminated Wells in FY2020
Last update date April 2, 2024
On this page, among the contaminated well follow-up surveys conducted by the Water and Soil Environment Division in Reiwa 2 (2020), 2-chome, Tsurumi-ku, Hino 5-chome, Konan-ku, Higashimatanocho, Totsuka-ku, Nakatakita 1-chome, Izumi-ku, Izumi-ku (former Izumi-ku), Shinba-cho, Kohoku-ku, Arai-cho, Hodogaya-ku.
| Survey point number | Standard value | 701 | 705 | 720 | 720 | 722 | 723 |
|---|---|---|---|---|---|---|---|
| Prefectural mesh number | Nothing | 2534 | 0476 | 0349 | 0349 | 1400 | 1400 |
| Ward name | Nothing | Tsurumi Ward | Konan Ward | Totsuka Ward | Totsuka Ward | Izumi Ward | Izumi Ward |
| Street name | Nothing | 2, Yakou | 5, Hino | Higashimatanocho | Higashimatanocho | 1, Nakatakita | 1, Nakatakita |
| Date of collection | Nothing | October 22, 2020 | October 1, 2020 | October 1, 2020 | December 24, 2020 | October 8, 2020 | October 8, 2020 |
| Cadmium (environmental standard items) | 0.003 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| All cyanes (environmental standard items) | Not detected | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Lead (environmental standard items) | 0.01 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Hexavalent chromium (environmental standard items) | 0.05 | Unexamined | Unexamined | Unexamined | <0.02 | Unexamined | Unexamined |
| Arsenic (Environmental Standard Items) | 0.01 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Total mercury (environmental standard items) | 0.0005 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| PCBs (environmental standard items) | Not detected | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Dichloromethane (environmental standard items) | 0.02 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Carbon tetrachloride (environmental standard items) | 0.002 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Vinyl chloride monomer (environmental standard items) | 0.002 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| 1,2-dichloroethane (environmental standard items) | 0.004 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| 1,1-dichloroethylene (environmental standard items) | 0.1 | <0.0002 | 0.0004 | 0.0006 | Unexamined | <0.0002 | <0.0002 |
| 1,2-dichloroethylene (environmental standard items) | 0.04 | 0.086 | 0.071 | 0.0007 | Unexamined | 0.010 | 0.0082 |
| 1,1,1-trichloroethane (environmental standard items) | 1 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| 1,1,2-trichloroethane (environmental standard items) | 0.006 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Trichloroethylene (Environmental Standards) | 0.01 | 0.012 | 0.089 | 0.0044 | Unexamined | 0.0019 | 0.0011 |
| Tetrachloroethylene (Environmental Standards) | 0.01 | <0.0002 | 0.11 | 0.015 | Unexamined | 0.36 | 0.10 |
| 1,3-dichloroppine (environmental standard items) | 0.002 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Tylum (environmental standard items) | 0.006 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Shimadine (environmental standard items) | 0.003 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Thiobencarb (environmental standard items) | 0.02 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Benzene (environmental standard items) | 0.01 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Selenium (environmental standard items) | 0.01 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Nitrate nitrogen and nitrite nitrogen (environmental standard items) | 10 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Fluorine (environmental standard items) | 0.8 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Boron (environmental standard items) | 1 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| 1,4-dioxane (environmental standard items) | 0.05 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Chloroform (city original) | 0.06 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Electric conductivity (mS/m) (General item) | Nothing | 31.5 | 54.5 | 30.5 | 27.4 | 26.3 | 32.9 |
| pH (general items) | 5.8 or more 8.6 or less | 6.0 | 8.4 | 6.5 | 6.3 | 5.7 | 6.6 |
| Water temperature (°C) (General item) | Nothing | 19.9 | 16.9 | 18.8 | 16.3 | 20.7 | 18.2 |
| Odor (general items) | Nothing | Odor-free | Odor-free | Odor-free | Odor-free | Odor-free | Odor-free |
| Appearance (general items) | Nothing | Colorless and transparent | Light brown | Muddy | Muddy | Colorless and transparent | Colorless and transparent |
| Survey point number | Standard value | 724 | 726 | 729 | 731 | 741 |
|---|---|---|---|---|---|---|
| Prefectural mesh number | Nothing | 1400 | 1400 | 1309 | 2438 | 1484 |
| Ward name | Nothing | Izumi Ward | Izumi Ward | Izumi Ward | Kohoku Ward | Hodogaya Ward |
| Street name | Nothing | 1, Nakatakita | 1, Nakatakita | 2, Izumichuokita | Nippa-cho | Niimachi |
| Date of collection | Nothing | October 8, 2020 | October 8, 2020 | October 8, 2020 | October 22, 2020 | October 22, 2020 |
| Cadmium (environmental standard items) | 0.003 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| All cyanes (environmental standard items) | Not detected | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Lead (environmental standard items) | 0.01 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Hexavalent chromium (environmental standard items) | 0.05 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Arsenic (Environmental Standard Items) | 0.01 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Total mercury (environmental standard items) | 0.0005 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| PCBs (environmental standard items) | Not detected | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Dichloromethane (environmental standard items) | 0.02 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Carbon tetrachloride (environmental standard items) | 0.002 | Unexamined | Unexamined | Unexamined | <0.0002 | Unexamined |
| Vinyl chloride monomer (environmental standard items) | 0.002 | Unexamined | Unexamined | Unexamined | Unexamined | <0.0002 |
| 1,2-dichloroethane (environmental standard items) | 0.004 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| 1,1-dichloroethylene (environmental standard items) | 0.1 | <0.0002 | <0.0002 | <0.0002 | <0.0002 | Unexamined |
| 1,2-dichloroethylene (environmental standard items) | 0.04 | 0.012 | 0.0004 | <0.0004 | 0.0012 | 0.26 |
| 1,1,1-trichloroethane (environmental standard items) | 1 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| 1,1,2-trichloroethane (environmental standard items) | 0.006 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Trichloroethylene (Environmental Standards) | 0.01 | 0.0014 | <0.0002 | <0.0002 | 0.014 | 0.10 |
| Tetrachloroethylene (Environmental Standards) | 0.01 | 0.16 | 0.089 | 0.16 | <0.0002 | Unexamined |
| 1,3-dichloroppine (environmental standard items) | 0.002 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Tylum (environmental standard items) | 0.006 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Shimadine (environmental standard items) | 0.003 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Thiobencarb (environmental standard items) | 0.02 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Benzene (environmental standard items) | 0.01 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Selenium (environmental standard items) | 0.01 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Nitrate nitrogen and nitrite nitrogen (environmental standard items) | 10 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Fluorine (environmental standard items) | 0.8 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Boron (environmental standard items) | 1 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| 1,4-dioxane (environmental standard items) | 0.05 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Chloroform (city original) | 0.06 | Unexamined | Unexamined | Unexamined | Unexamined | Unexamined |
| Electric conductivity (mS/m) (General item) | Nothing | 23.7 | 26.5 | 25.4 | 28.6 | 18.8 |
| pH (general items) | 5.8 or more 8.6 or less | 6.2 | 6.6 | 6.4 | 6.3 | 6.2 |
| Water temperature (°C) (General item) | Nothing | 17.1 | 19.5 | 18.8 | 17.0 | 18.1 |
| Odor (general items) | Nothing | Odor-free | Odor-free | Odor-free | Odor-free | Odor-free |
| Appearance (general items) | Nothing | Colorless and transparent | Colorless and transparent | Colorless and transparent | Colorless and transparent | Colorless and transparent |
(Concentration unit: mg/L)
- The pH value is the standard value for tap water quality.
- The reference value for chloroform is the guideline value for monitoring items (outside site).
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: 113-012-643
