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Metropolitan Water Reclamation District of Greater Chicago

Resource Recovery Program Update

The MWRD’s Resource Recovery Program for Enhanced Biological Phosphorus Removal (EBPR) is now fully implemented and established at both the Calumet and Stickney Water Reclamation Plants (WRPs). Tanker truck loads of approved high strength organic material (HSOM) may now be delivered to either WRP for enhancement of the process that recovers phosphorus from wastewater.

Since the first load of HSOM was received at the Stickney WRP in April of 2017, approximately 150 similar loads have been received and processed at the Stickney WRP and approximately 350 loads of HSOM have been received and processed at the Calumet WRP for a total intake volume of over 1,000,000 gallons. Ample EBPR capability still remains at both WRPs so it is not too late to utilize the MWRD as the final destination and end-user for your HSOM. Types of acceptable HSOM are: food processing, brewery, restaurant and sugar/starchy wastes which are homogenous liquids or slurries high in organic content that are too concentrated to be disposed to the sewer system. Spent yeast, grains and hops are examples of wastes that can be delivered to the MWRD.

All relevant program documents and application materials may be downloaded from our website. Please contact us at for further assistance.  

We look forward to partnering with you in our ongoing efforts to recover valuable resources.

Summary Review of Effluent Limitations Guidelines and Standards for the Dental Category, Final Rule

The Dental Amalgam Rule (40 CFR 441) was signed by USEPA on December 15, 2016, and published in the Federal Register on June 14, 2017. The purpose of the rule is to set a uniform national standard that will greatly reduce the discharge of mercury to publicly owned treatment works (POTWs) and the environment. 

USEPA is working to promulgate technology-based pretreatment standards under the Clean Water Act to reduce discharges of mercury from dental offices into municipal water reclamation plants (WRPs). Mercury is a potent neurotoxin that bioaccumulates in the aquatic food chain. Mercury pollution is widespread globally and originates from many diverse point sources, including municipal and industrial solid waste incinerators, coal-burning power plants and other forms of fossil fuel combustion. Because municipal WRPs cannot remove mercury in wastewater, it passes through treatment processes to receiving streams and is concentrated in biosolids which are then often land-applied. Dental offices, which discharge mercury present in filling amalgam, are the main point sources for mercury discharged to POTWs. Once discharged, bacteria in the environment convert elemental mercury to the more toxic methylmercury. It is easier to remove mercury from dental amalgam when it is in a concentrated form than when it is diluted. Accordingly, USEPA issued this rule in an effort to prevent mercury releases to the environment before it becomes hazardous to humans and aquatic life.

This final rule requires dental offices to install amalgam separators and implement two best management practices (BMPs) recommended by the American Dental Association (ADA), one which prohibits the discharge of waste or “scrap” and another which prohibits the use of acidic or oxidizing line cleaners that may lead to the dissolution of solid mercury when cleaning chairside traps and vacuum lines. Amalgam separators are affordable and readily available technology for capturing waste  mercury generated at dental offices. The mercury captured by separators can then be recycled and reused.

In addition to the above, the rule minimizes the administrative burden on dental offices subject to the rule, as well as federal, state and local regulatory authorities responsible for oversight and enforcement of the rule. Administrative burden was the main concern of POTW commenters on the 2014 proposed rule and USEPA has eased that burden in the final rule through extensive streamlining. While other industries subject to categorical pretreatment standards typically consist of tens to hundreds of facilities, the dental industry consists of over 130,000 offices subject to the rule. Application of default General Pretreatment Regulations (GPR) reporting and compliance requirements to such a large number of facilities would be exceedingly challenging and burdensome for control authorities. Therefore, this final rule exempts dental offices from GPR oversight and reporting requirements.

In order to streamline implementation and simplify compliance requirements for dental offices, the final rule establishes that dental offices are not Significant Industrial Users (SIUs) as defined under 40 CFR 403 and are not Categorical Industrial Users (CIUs) as that term is used in the GPR. As a result, control authorities are not required to implement the traditional suite (e.g. permits, annual inspections and sampling studies) of oversight and enforcement requirements that would normally become applicable once a categorical standard is promulgated. Dental offices, clinics and dental schools subject to the rule are required to submit a one-time compliance certification report to the control authority in order to demonstrate compliance with the performance standard and the ADA’s BMPs. At the same time, however, USEPA recognizes that any control authority has discretionary authority to treat a dental office as an SIU and/or CIU if warranted. Additional information, documents and FAQs with regard to the Dental Amalgam Rule can be found at


RD-925 Submittal Due Date 

The User Charge Annual Certified Statement (RD-925) for the 2017 reporting year is due February 20, 2018. The RD-925 form is available on the District’s website.

Merged Sampling Data and RD-920 Sampling Requirements 

The MWRD has emailed merged District and User data if the District sampled your facility and if the User provided sample results reported on the User Charge Certified Sampling Analysis Reporting Statement (RD-920). If both criteria are met and you have not received merged District and User sample results via email please contact the District’s Environmental Specialist (E.S.) assigned to your facility. The E.S. will explain in the email if isolation of sample results were allowed. This courtesy is to help facilitate filings that reflect the User Charges owed. 

The RD-920 has been updated and the online RD-920 instructions reflect the updates. The updates include: RD-920s are due 45 days after completion of a sampling study. The exception to this due date is if sampling was conducted from December 19 through December 31. RD-920s reporting sample analysis during this period is due by Jan 31 of the following year. Sampling conducted after December 31 must be applied to the year in which it was collected; it cannot be applied to the previous year. If sampling was not conducted in the reporting year by the User, the District will apply the best available data. 

Users with multiple outlets must sample the outlets simultaneously for User Charge purposes. If a sample is not collected at one of the outlets, the log sheets must reflect the missed sample along with an explanation why the sample was not collected. The District may not accept sample results if outlets are not sampled simultaneously. 

District provided split samples for the User is for informational purposes only. District split sample results cannot be submitted to the District on the RD-920 or the Continued Compliance Report (RD-115).

Postmark Date and Receive Date

The District has received date sensitive filings without a postmark date. Date sensitive filings without a postmark date will be considered received when the District time stamps the filing. It generally takes four days for the District to receive regular mail from the User. If a filing is mailed on the due date, the postmark date is applied and the filing is considered on time. Filings mailed on the due date without a postmark date will be late and a late filing fee will be issued.

RD-114 Final Compliance Sampling Report 

A Cease and Desist (C&D) for a violation requires compliance sampling and the submittal of a Compliance Schedule (RD-112) and a Final Compliance Report (RD-114). The RD-112 requires detailed description of all remediation measures for the User to attain compliance. Increments of progress must be indicated along with milestone dates for implementation of remediation measures as well as an acceptable final compliance date by which the respondent will attain full compliance with the District’s Sewage and Waste Control Ordinance. The RD-114 will contain the analytical results of sampling conducted to verify that compliance has been attained. Due to the complexity of a C&D, sampling conducted to satisfy the requirements of an RD-115 may not be used to satisfy the sampling requirements for a C&D.


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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