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Metropolitan Water Reclamation District of Greater Chicago

Change in Monitoring Requirements for Discharge Authorization

The Metropolitan Water Reclamation District of Greater Chicago (District) received recommendations from the United States Environmental Protection Agency’s (USEPA) Enforcement and Compliance Assurance Division regarding proper monitoring methods for hexavalent chromium (Cr+6). To date, Discharge Authorizations (DA) issued to industrial users by the District have specified that Cr+6 be collected and analyzed only as a grab sample. However, USEPA has advised that pursuant General Pretreatment Regulations for Existing and New Sources of Pollution at 40 CFR 403.12(g), Cr+6 shall always be collected and analyzed as a 24-hour composite sample. 

Therefore, in light of the above, all District-issued DAs will be revised to reflect USEPA guidance for monitoring for Cr+6, as follows, effective January 1, 2022. 

  1. Under Special Condition 2. Monitoring Requirements: Reference to grab sample collection for Cr+6 is deleted. 
  2. Under Special Condition 3. Effluent Limits: Reference to RD-115 Sample Type for Cr+6 is revised from Grab to Composite 

Prior to the effective date, revised versions of Special Conditions 2 and 3 of your DA will be transmitted to you in a separate written correspondence for your use and inclusion in your approved DA. Please disregard earlier versions of Special Conditions 2 and 3 once these revised pages are received. No further action on your part is required at this time. 

If you have any further questions or concerns, please contact the District’s Pretreatment and Cost Recovery Section at (312) 751-3044, or at

New Discharge Authorization Request (RD-118) Form

On June 1, 2021, the new Discharge Authorization Request (DAR) form, or RD-118, became available on the District’s website (www. The new form as well as instructions and a completed example can be found on the Preatment Program page

The 1997 DAR form is still available on the District’s website, but should only be used for current Significant Industrial Users (SIU) requesting a revision to their current and approved Discharge Authorizations (DA). The 2021 DAR form must be used for new requests for a DA, changes to a SIUs regulated category, or changes in ownership. 

Electronic Reporting

In 2020, M&R began development of an electronic self-reporting system.  The system is compliant with USEPA Cross Media Electronic Reporting Rule, which is also known as CROMERR. The system allows users to electronically submit self-monitoring data and permit applications to M&R.  Currently, users mail a hardcopy of reports that M&R would then manually enter in its database system.  M&R anticipates a partial deployment of electronic reporting capabilities for use by its users by the end of 2021. This will require users to register prior to using the system.  Registration materials will be mailed to users when the system is ready.

Results of the Customer Service Survey for 2020 Reporting Year

The Industrial Waste Division (IWD) of the Monitoring and Research (M&R) Department conducted a customer service survey of the commercial, industrial and tax-exempt users that report annually in accordance with the District’s User Charge Ordinance for the 2020 reporting year. Since 2016, the M&R Department requests users to fill out a survey annually. The survey ended on June 1, 2020.  IWD received only three responses for the survey. The results of the survey, as well as those obtained from other years, are as follows: 

(see the PDF newsletter for the chart graphic)


Established in 1889, the Metropolitan Water Reclamation District of Greater Chicago (MWRD) is an award-winning, special purpose government agency responsible for wastewater treatment and stormwater management in Cook County, Illinois.


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