Turtle Park Wastewater Treatment Plant

 LOCATION: Oak Ridge, Tennessee

 KEY PERSONNEL:

• Steve Bostic

 DATES: 2003

  COST: $10 Million

 PROJECT HIGHLIGHTS:

• P-Chem Train & Process
• Unique Process Implemented
• Complex Wet & Dry Flows
• Multi-Route Flow Process

Based on an agreement with the State of Tennessee to eliminate chronic overflows at its wastewater treatment plant, the City of Oak Ridge commissioned LDA to design a larger treatment facility.  Adding to the complexity of the project was the wide variation of dry weather flow and wet weather flow.  LDA determined that the plant needed to accommodate wet weather flows up to 30 MGD, while the average dry weather flows were 4.5 MGD.

As part of the plant upgrades, LDA designed a new fine screening facility with three internally fed rotating drum screens.  Each of the screens were rated at 10 MGD.  After screening, the flow is split into a biological train and a physical-chemical train.  The biological train, designed by LDA, can handle up to 14 MGD flow of biochemical oxygen demand at 250mg/l through an activated sludge process and conventional clarification.

The settled effluent is then filtered through mixed media gravity filters prior to disinfection.  In addition, the physical-chemical process includes chemical coagulation, flocculation, and clarification.  The clarification occurs in two circular units, utilizing tube settlers to minimize the required surface area, and the two streams are blended before disinfection.  Disinfection is performed using a UV process, and prior to discharge, a cascade aeration channel reaerates the effluent.  On-site generators were also implemented to provide the plant with auxiliary power.

The plant has been through two NPDES cycles and continues to meet discharge criteria.  LDA provided design, contract administration, and resident project representative services, as well as developed an operations and maintenance manual.  At that time, the Turtle Park Plant was the only plant in the State of Tennessee to meet the EPA blending criteria, and this project was awarded the top award in the wastewater category a state wide Engineering Excellence Award.