The Wastewater Reporting Fee is 250€ per year and is active for 12 months from the date of the payment. Throughout the active subscription, more wastewater test reports can be uploaded and it is recommended to at least twice a year in April and October, as outlined in the ZDHC Wastewater Guidelines.
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No, each manufacturing unit with a separate address should have its own ZDHC Gateway account and separate wastewater reporting.