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NPDES - Application for Non-Select Water Treatment Additives


Water Treatment Additives (WTA) include any material that is added to water used at a facility or to a wastewater generated by the facility to condition or treat the water.  Biocides, algaecides, herbicides, sanitizers, flocculants, and lubricants are examples of water treatment additives that can be found in the wastewater of facilities.  WTAs that are discharged to surface waters of the state from a National Pollutant Discharge Elimination System (NPDES) permitted discharge or a groundwater discharge permit require prior review and approval by the Water Resources Division (WRD).  Permittees should check their NPDES permit and/or groundwater discharge permit requirements to determine if they need to apply prior to using a WTA.  As such, these WTA products must be included in the application for wastewater discharge, or requested during the permit cycle.  WTAs must be reviewed whenever they are changed; the use of the new WTA could change the characteristics of the wastewater effluent.  Both groundwater and NPDES permits require prior review and approval before new WTA can be used.  The process to receive approval to discharge a water treatment additive includes submittal of the following information to the WRD by the NPDES permittee proposing to use/discharge the product:

  1. The water treatment additive Safety Data Sheet (SDS).
  2. Ingredient information:  Name of each ingredient, CAS number for each ingredient, and fractional content by weight for each ingredient.
  3. The proposed water treatment additive discharge concentration (mg/l or µg/l) with supporting calculations.
  4. The discharge frequency (i.e., number of hours per day, week, etc.)
  5. The outfall the water treatment additive is to be discharged from.
  6. The type of removal treatment, if any, that the water treatment additive receives prior to discharge with percentage removed by each treatment.
  7. The water treatment additive function (i.e., microbiocide, flocculant, etc.).
  8. The SDS shall include a 48-hour LC50 or EC50 for a North American freshwater planktonic crustacean (either Ceriodaphnia sp., Daphnia sp., or Simocephalus sp.).  The results shall be based on the whole water treatment additive, shall not be results from a similar product, and shall not be estimated.
  9. The SDS shall also include the results of a toxicity test for one other North American freshwater aquatic species (other than a planktonic crustacean) that meets a minimum requirement of Rule 323.1057(2)(a) of the Water Quality Standards.  The results shall be based on the whole water treatment additive, shall not be results from a similar product, and shall not be estimated.  Examples of tests that would meet this requirement include a 96-hour LC50 for a rainbow trout, bluegill, or fathead minnow.

Request forms to discharge a water treatment additive to a surface water body should be filled out and submitted through 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 on begin submission for Service Request – Non-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 or via email.

By providing the information described in items 1 through 9 above, we will be able to provide an expeditious review of your request. 

You will be notified via email that your Non-select Water Treatment Additive Request has been received.  Additional notifications will be sent when key events are recorded or when submission processing milestones are achieved.