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City of Hattiesburg, MS Clean Water Act Settlement Information Sheet

On Wednesday, August 26, 2020, the United States Department of Justice, on behalf of the U.S. Environmental Protection Agency, and the State of Mississippi, acting through the Mississippi Department of Environmental Quality (MDEQ), lodged a proposed Consent Decree with the City of Hattiesburg, Mississippi. The goal of the proposed Consent Decree is for the City to eliminate sanitary sewer overflows (SSOs), and to achieve and maintain full compliance with the Clean Water Act (CWA), the Mississippi Air and Water Pollution Control Law, and the City's National Pollutant Discharge Elimination System (NPDES) Permits. 

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Overview of Company

Hattiesburg owns and operates two Wastewater Treatment Plants (WWTPs): the Hattiesburg South WWTP, also referred to as the South Lagoon, and the Hattiesburg North WWTP, also known as the North Lagoon. Both treatment plants use an aerated lagoon type of treatment system. Hattiesburg also owns and operates the Wastewater Collection and Treatment System (WCTS) associated with the two lagoons, which includes over 300 miles of gravity sewer lines, approximately 15.2 miles of force main pipe, approximately 5,700 manholes, 75 lift stations, and associated appurtenances. Hattiesburg’s WCTS is a separate sewer system designed to convey only municipal and industrial sewage, not stormwater.

Hattiesburg’s total estimated service population is approximately 41,241, not including residents from the City of Petal. In addition to its own service areas, Hattiesburg collects and transports sewage from the City of Petal, Mississippi for treatment at its South Lagoon facility. The City of Petal is an external jurisdiction with a service population of approximately 9,573 and is responsible for the operation and maintenance of its own WCTS.

Hattiesburg is permitted to discharge treated sewage from its Lagoons into the Leaf River and the Bouie River. The Bouie River is a major tributary of the Leaf River. The Leaf and Bouie Rivers are waterbodies within the Pascagoula River Basin. The Pascagoula River eventually discharges into Pascagoula Bay before entering the Gulf of Mexico. The State of Mississippi has developed Total Maximum Daily Loads (TMDLs), under Section 303(d)(1)(C) of the CWA, for segments of the Leaf and the Bouie Rivers that are directly impacted by Hattiesburg’s sewer system. TMDLs were developed for the Leaf River for fecal coliform and nutrients. TMDLs were developed for the Bouie River for sediment, low dissolved oxygen, and nutrients.

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The proposed Consent Decree addresses CWA violations by Hattiesburg with respect to its publicly owned treatment works in Mississippi, including numerous SSOs and violations of its NPDES permit as a result of its failure to properly operate and maintain its Wastewater Collection and Transmission Systems.

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Injunctive Relief

Hattiesburg estimates that it will spend approximately $35 to $45 million over approximately 16 years (196 months) to complete the injunctive relief and bring its operations into compliance with the CWA.

The Consent Decree requires Hattiesburg to undertake several Early Action Projects to replace and/or rehabilitate certain portions of the WCTS and are intended to address conditions that are causing SSOs in the WCTS. The City will complete the Early Action Projects by December 31, 2024 and estimates that it will spend approximately $14,293,000 on the Early Action Projects.

The Decree also requires the City to perform sewer assessment and rehabilitation work in two “Priority Areas” to, among other things, address infiltration and inflow (I/I), structural defects, and other conditions causing, or that are likely to cause, SSOs. The Priority Areas represent approximately forty-three percent (43%) of the WCTS by linear foot, and the vast majority of the City’s wet weather capacity related SSOs. The Consent Decree requires a sewer system evaluation/rehabilitation (SSER) for the Priority Areas. The SSER will include the following components: corrosion defect identification; manhole condition assessment and rehabilitation; flow monitoring; closed circuit television inspection; gravity sewer line defect analysis and rehabilitation; smoke testing; force main condition assessment and rehabilitation; and pump station performance and rehabilitation.

The Consent Decree also requires Hattiesburg to develop and implement specific and comprehensive management, operations, and maintenance, also referred to as MOM, programs including: a sewer overflow response plan; an emergency response plan; an information management system program; a sewer mapping program; a gravity sewer system operations and maintenance program; a pump station operations and preventative maintenance program; a fats, oils, and grease control program; a training program; and a Priority Areas chronic SSO advanced remote monitoring program.

To increase transparency, the Consent Decree requires Hattiesburg to post on its website all deliverables that are to be prepared and/or submitted pursuant to the Consent Decree, along with instructions to the public for receiving email notice when deliverables are posted. In addition, the Consent Decree requires Hattiesburg to allow the public an opportunity to comment on the major deliverables before Hattiesburg submits them to the EPA for review.

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Pollutant Impacts

Through the implementation of the proposed consent decree, the following estimated annual pollutant reductions will result:

  • 1,013 pounds of total suspended solids;
  • 970 pounds of biochemical oxygen demand;
  • 2,428 pounds of chemical oxygen demand;
  • 157 pounds of total nitrogen; and
  • 22 pounds of total phosphorous

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Health and Environmental Effects

  • Total Suspended Solids (TSS) – TSS indicates the measure of suspended solids in wastewater, effluent or water bodies. High levels of TSS in a water body can diminish the amount of light that penetrates the water column and reduce photosynthesis and the production of oxygen.
  • Biological Oxygen Demand (BOD) – BOD is an indirect measure of the biologically degradable material present in organic wastes. High BOD means there is an abundance of biologically degradable material that will consume oxygen from the water during the degradation process. It may take away oxygen that is needed for aquatic organisms to survive.
  • Nutrients – Excess levels of nitrogen and phosphorus in waters can produce harmful algal blooms. These blooms contribute to the creation of hypoxia or “dead zones” in water bodies where dissolved oxygen levels are so low that most aquatic life cannot survive

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Civil Penalty

In addition to these compliance costs, the proposed Consent Decree also requires Hattiesburg to pay a civil penalty of $165,600, to be divided equally between the United States and the State of Mississippi. The proposed Consent Decree also includes a Supplemental Environmental Project (SEP) valued at $220,800, which will result in the reduction of extraneous flows entering the WCTS through defective private laterals and through illicit connections from residential properties the owners of which face financial hardship.

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State Partner

The State of Mississippi, acting through its Department of Environmental Quality (MDEQ), has joined as a co-plaintiff and brings its own parallel claims under the Mississippi Air and Water Pollution Control Law.

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Comment Period

The proposed consent decree was published in the Federal Register on September 1, 2020 and is subject to a 30-day public comment period and court approval. It will be available for viewing on the DOJ’s website until the public comment period closes on October 1, 2020.

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For more information, contact:

James Zimny
Water Enforcement Division
U.S. Environmental Protection Agency
1200 Pennsylvania Ave., NW (Mail Code 2243A)
Washington, DC, 20460
(202) 564-6551

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