Select Water Treatment Additives Discharge Application Instructions

Contacts:

• Jack Farrelly, Aquatic Biologist, FarrellyJ1@Michigan.gov or 517-599-9943
• Darrin McCullough, Aquatic Biologist, McCulloughD@Michigan.gov or 517-242-8647

Select Water Treatment Additives (WTAs) are those commonly used chemical products that are added as conditioners to improve the water quality for use in a system or process, condition and treat the water to make it suitable for discharge, are considered to not adversely affect aquatic life, are a single chemical (i.e., not a mixture of chemicals), and can be regulated through a facility's National Pollutant Discharge Elimination System (NPDES) permit with a chemical specific water quality-based effluent limit (WQBEL), using a parameter that mitigates the WTA toxicity (i.e., pH limits that mitigate a pH adjusting WTA).

The following chemicals are considered to be Select WTAs and are commonly used disinfectants and dechlorinating agents, flocculants, pH adjusters, water softeners, and oxygen scavengers.

The process to receive approval to use and subsequently discharge Select WTAs to a surface water of the state from an NPDES permitted outfall includes the following:

1. Connect to MiEnviro, our web-based permitting and compliance database.  Go to your facility site in MiEnviro, click on Apps, Requests and Reports, Start New Form, in the search box under form name enter additive, and click begin submission for the Service Request - Select Water Treatment Additive Request Form.  Please note that the permittee or other authorized user/editor must submit forms directly through the facility's MiEnviro page.  A request will not be processed if submitted on an unaffiliated page.
2. Upon submittal of your request, you will be notified via email that your Select Water Treatment Additive Request has been received and this notification will be your approval.  The Department will review your submission and contact you only if additional information is required. 
3. Only those Select WTAs included on the Select Water Treatment Additives List are authorized under this process.  The process to receive approval to discharge any WTA not included on the Select Water Treatment Additives List must follow the process outlined under Water Treatment Additive Discharge Application Instructions (Non-Select WTAs).
4. The facility must already possess an NPDES permit, and the outfall from which the Select WTA will be discharged must already be permitted under the NPDES permit.
5. The corresponding NPDES limit for the Select WTA must already be included in the NPDES permit for the outfall from which the WTA will be discharged.  Corresponding NPDES limits are included on the Select Water Treatment Additives List.
6. Required sampling to fulfill NPDES permit requirements must be conducted on effluent discharged from the outfall during a representative time period of Select WTA usage and discharge.

Select Water Treatment Additives List

NOTE:  Approval to discharge additives on this list must be obtained by the Water Resources Division prior to use and discharge of the additive.  The corresponding NPDES limit must already be included in the permit for the outfall from which the Select WTA will be discharged.  Additives that contain the following chemicals as a single constituent in the product (plus water) are considered to be Select WTAs.

Table 1: Select Water Treatment Additives - Disinfectants and Dechlorinating Agents

Table 2: Select Water Treatment Additives - Flocculants

Table 3: Select Water Treatment Additives - pH Adjusters and Water Softeners

Table 4: Select Water Treatment Additives - Oxygen Scavengers