The primary Wastewater Treatment Plant (WWTP) was built in 1955, along with the Combined Sewer Interceptor that collects storm and waste water in the same system. It generally parallels the Kentucky River and intercepts all combined sewers near their point of discharge.
At the time of construction all sewage from east and west Frankfort, Glens Creek and Fort Boone flowed through this combination sewer.
In 1972 the City requested a grant under PL 92-500 (commonly called the “Clean Water Act”) to expand the WWTP and construct major trunk sewers.
In 1990 the WWTP was expanded to 6.6 MGD at no cost to the City by recalculating the plant's design loadings. In 2001 the plant was again expanded to 9.9 MGD, with the construction of a third oxidation ditch and associated facilities.
Digestion Process Changes
The plant was originally constructed using anaerobic digestion. Anaerobic digestion is a process where microorganisms break down organic materials such as food scraps, manure, and sewage sludge in the absence of oxygen. This process reduces the waste to sludge and other biosolids.
In 1994, the covers of the anaerobic digesters were removed, and aerators were installed to convert from an anaerobic digestion process to an aerobic digestion process.
According to the EPA, the City allegedly violated provisions of the Clean Water Act by having multiple reoccurring sanitary sewer overflow occurrences which impacted the Kentucky River and its tributaries. Additionally, the EPA contended that the City had not complied with its Combined Sewer Overflow (CSO) Control Policy which required development of a Long Term Control Plan to mitigate the combined sewer overflows.
As a result, a Consent Judgment between the City and the Commonwealth of Kentucky Environmental and Public Protection Cabinet was entered into the Franklin County Circuit Court on September 5, 2007. Note: The Environmental and Public Protection Cabinet is now the Energy and Environment Cabinet.
2008 Administrative Order
On June 23, 2008, the City received an Administrative Order (AO) from EPA's Region 4 that required the City to submit certain documents and reports required by the Consent Judgment for comment and approval.
The Administrative Order issued by EPA on June 23, 2008, directs all CSOs, be mitigated by June 23, 2018 to 10 years after the date of the Administrative Order. A letter has been submitted to the EPA requesting the deadline for CSO mitigation be extended to match the dates in the Consent Judgment.
Requirements for the Enforcement Actions
All Sanitary Sewer Overflows (SSOs) shall be eliminated by September, 2015, 8 years after the Consent Judgment was signed.
All Combined Sewer Overflows (CSOs) shall be mitigated by December 31, 2023.
The Department has met many of the requirements over the past several years as summarized below. An Early Action Plan was submitted as required. It included the following:
Nine minimum goals were submitted by September 2008:
- Control of solid and floatable materials, including installation of devices where appropriate
- Maximization of flow to the Wastewater Treatment Plant (WWTP) for treatment
- Maximum use of the collections system for storage;
- Monitoring to effectively characterize CSO impacts and efficacy of CSO controls
- Pollution prevention;
- Prohibition of CSOs during dry weather, including provision for backup power where appropriate
- Public notification to ensure the public receives adequate notification of CSO occurrences and CSO impacts, including, if appropriate, improving the current signage at each CSO location to an easily readable type size and style
- Review and modification of pretreatment requirements to assure CSO impacts are minimized
- Proper operation and regular maintenance programs for the Combined Sewer System (CSS) and the Combined Sewer Overflows (CSOs)
Capital Improvements Project List was submitted. (See Back Pages)
Capacity Management Operations and Maintenance (CMOM) - responded to comments in April, 2014 and are currently awaiting approval.
Sewer Overflow Response Protocol (SORP) approved May 2010.
The following additional goals were accomplished:
- Sewer Use Ordinance was approved by the Division of Water in April, 2008.
- Mapping of the System was submitted to Kentucky Division of Enforcement and EPA in October, 2009.
- A Long Term Control Plan was submitted in June, 2009 and the Sewer Department responded to comments in September, 2014 and is currently awaiting approval.
- An Interim Long Term Control Plan (ILTCP) was approved in April, 2011.