ENVIRONMENTAL ASSESSMENT
AND
DRAFT FINDING OF NO SIGNIFICANT IMPACT
A. Project Identification
Name: Muskingum County – New Life Lift Station and Sanitary Force Main
Address: Board of Commissioners of Muskingum County
Courthouse
401 Main Street
Zanesville, OH 43701
WPCLF #: CS390060-0011
B. Proposed Project
1. Summary
The Board of Commissioners of Muskingum County, Ohiowas granted a $500,000 special appropriation from U.S. EPA in Federal Fiscal YearFY 2010 X to improve its wastewater collection (sanitary sewer) system in the unincorporated area of Maysville. Muskingum County has also requested approximately $1,000,000 from the Ohio Water Pollution Control Loan Fund (WPCLF) and has a commitment for a $100,000 grant from the federal Appalachian Regional Commission for this project that will replace an undersized and aged sanitary sewage lift station and construct a new force main to carry project area flows to anexisting sewer with sufficient capacity.
The proposed work involves construction adjacent to the existing New Life Lift Station, and along a major road and across easements on parking lots, all areas previously disturbed for construction and lacking important environmental resources. Standard construction environmental protection practices will be implemented to ensure the project has no significant environmental impact.
Muskingum County anticipates no sewer rate increase for this project.
2. Project Background
a. History and Existing Conditions
A history of violations by Muskingum County of Ohio’s water pollution control laws and of the National Pollutant Discharge Elimination System (NPDES) permits for the county’s wastewater treatment plants and sewer systems led to enforcement action and a 2003 Consent Order (Order) signed by the State of Ohio and Muskingum County. The Order requires elimination of sanitary sewer overflows (SSO) in the county system. The Order required within three years an assessment of the county sanitary sewer collection system and preparation of a report describing the system and identified problems, a plan for design and construction to correct identified problems, and a schedule for remediation.
The Order included a civil penalty of $25,000 to be paid by Muskingum County to the State of Ohio, and a Supplemental Environmental Project in lieu of an additional civil penalty of $115,000. The Supplemental Environmental Project, to be financed by Muskingum County, was construction of sanitary sewers in the Lakeland Hills subdivision identified in the Order to eliminate approximately 100 failing septic systems that were polluting local surface water.
When evaluating a system like Muskingum County’s, it should be noted that sanitary sewers and wastewater treatment plants function optimally within a range of flows of sanitary sewage only. Additional clear water flows, whether from downspouts, leaky manholes, or other connections to sewers (inflow) or from ground water entering cracks in the sewer (infiltration), can exceed the capacity of the sewers and wastewater treatment plant (WWTP) and cause operational problems and/or direct discharge of untreated wastewater to surface water. Significant inflow and infiltration (collectively referred to as “I/I”) has been identified in the county-owned sewer systems, and has directly contributed to SSO in the South System.
Muskingum County submitted the required report to Ohio EPA in 2009, with a schedule to eliminate SSO in the South System by March 2012. In 2011, the County requested a five-year extension for South System corrections and Ohio EPA agreed to the proposed March 2017 SSO elimination deadline.
Much of the South System was constructed piecemeal and later incorporated into the County system, including a large portion of variable grade, small diameter sewers that drain septic tanks. The County began managing the system by pumping the septic tanks, then inspecting the tanks and correcting obvious problems. Those repairs eliminated some of the SSO problems.
Conventional gravity sewers serve the remainder of the South System. Fourteen pump stations and sixteen “septic tank effluent pump” – STEP – stations of varying ages and conditions present challenges to the County maintenance staff. The New Life Lift Station, with a history of regular SSO events, receives flow from an area with eight pump stations, gravity sewers, and four mobile home parks with identified I/I sources that have been largely corrected. Based partly on analysis of pump station operations, County staff have identified and eliminated several significant sources of I/I, including broken pipes, buried manholes, a water main break, vandalized manholes to provide storm water drainage, and illegal sump pump and gutter connections to sanitary sewers.
The County has monitored SSO events at the New Life Lift Station since 2011. The elimination of identified I/I sources cannot eliminate all I/I flows, however, and the New Life Lift Station still experiences overflows with heavy rainfalls.
b. Population and Flow Projections
Sewer customers in the New Life Lift Station service area are primarily residential and commercial; no significant industry is in the area. Approximately 550 single family dwellings and 220 mobile home units are in the service area. County approval of a proposed 15-building apartment complex of 360 units in the service area is pending. Commercial water use is modest, approximately 24,800 gallons per day. County approval is also pending for a proposed mixed-used commercial development on 48 acres.
The existing and proposed uses are calculated to generate a peak hourly flow of 1,135 gallons per minute (GPM). Proposed future commercial flows would add 218 GPM peak flow and proposed future residential flows would add 180 GPM. Thus, projected peak flow sewer capacity, and New Life Lift Station capacity, totals 1,533 GPM.
c. Water Quality
Surface water in the New Life Lift Station service area drains to Jonathan Creek and lower Moxahala Creek, which is a direct tributary of the Muskingum River. The “2012 Total Maximum Daily Loads for the Moxahala Creek Watershed Final Report” describes causes of water quality problems: acid mine drainage, habitat alterations(dam), nonpoint source runoff, and failing home sewage treatment systems.
In the immediate project area, Jonathan Creek is in full attainment of its state designated Warmwater Habitat (WWH)aquatic life use criteria, a measure of biological health, and in non-attainment of the recreation criteria, partly based on elevated bacteria levels. Livestock agriculture and septic systems for residential wastewater treatment in most of the watershed have led to widespread elevated bacteria counts.
Moxahala Creek in the project area is in full attainment of its WWH criteria and in non-attainment of the recreation criteria. Sanitary sewer overflows, failing septic systems, and livestock cause elevated bacteria counts.
3. Discussion of Feasible Alternatives
Muskingum County evaluated three feasible alternatives to eliminate SSO from the New Life Lift Station, based on agreement with Ohio EPA that “eliminate” means no SSO in the South System except for rain events of more than 2 inches in a 24-hour period or a snowmelt of more than 6 inches in 24 hours. The County must prove to Ohio EPA that these criteria are met for SSO occurrences after March 2017.
Doing nothing, the "no-action" alternative, is not feasible because it would allow SSO and the associated potential threats to human health to continue, which would violate Ohio law and the Consent Order.
The feasible alternatives are options to eliminate (Alternative 1 – I/I Identification and Reduction), transport (Alternative 2 – Increase New Life Lift Station Pumping Capacity), or store excess wet-weather flows (Alternative 3 – Provide Overflow Storage at the New Life Lift Station). Each alternative was evaluated on estimated construction costs; operation, maintenance, and replacement costs; and environmental footprint.
Alternative 1 – I/I Identification and Reduction – Muskingum County had identified areas suspected as significant I/I contributors in the South System (four mobile home parks and three subdivisions). Mobile home parks often are significant I/I contributors, and the county has successfully encouraged the owners to correct identified I/I sources. I/I reduction from the mobile home parks was significant. Broadview Circle subdivision had been served by individual septic tanks that drained to small sewers. Each septic tank was susceptible to infiltration and county staff had observed groundwater flowing into tanks. The proximity to gravity sewers allowed the county to self-finance the minor addition of new gravity sewers to replace the small sewers and septic tanks. New Southern Hills subdivision is served by a gravity sewer and had been a major source of flow to the New Life Lift Station. The county has rehabilitated sewers in this area to minimize extraneous flows. Avondale subdivision, like Broadview Circle,has septic tanks that drain to minimally-sloped gravity sewers. Flow monitoring suggests this system is especially leaky, each septic tank being a source of infiltration and, depending on lot topography, inflow. A project to construct conventional gravity sewers and a pump station serving Avondale residences to eliminate the septic tanks is already designed and will be constructed starting in 2014.
Although I/I reduction can decrease flows and extraneous flows have been minimized in the South System, sufficient reduction to eliminate overflows downstream with no other improvements is unlikely.
Alternative 2 – Increase New Life Lift Station Pumping Capacity – Overflows at the New Life Lift Station have been regularly recorded in recent years. The estimated peak flow to New Life is 1,533 GPM. Recent pump testing suggests the South Avenue Lift Station (1,200 GPM capacity)that receives flows from the New Life Lift Station, can accept increased flow from New Life Lift Station without causing overflows at South Avenue. A proposed 12” diameter force main running from a new New Life Lift Station with variable frequency drive pumps would drain directly to an existing 12” diameter gravity sewer and allow flows to reach South Avenue Lift Station without overflows except during excessive rain events. Engineer’s estimated cost, for planning comparison - $958,600.
This alternative would reduce the frequency of SSO event, requires little land acquisition, and costs less than Alternative 3. This alternative leaves some uncertainty about the potential for overflows from the South Avenue Lift Station; if they occur, overflow storage as proposed in Alternative 3 may be required. The New Life Lift Station is aging and would require pump upgrades in the foreseeable future regardless of this project.
Alternative 3 – Provide Overflow Storage at the New Life Lift Station – Instead of increasing the pump station capacity, add overflow storage at the pump station site. When flows exceed the capacity of the pump station, excess flows would be pumped into a below-ground basin, allowing the pump station to continue operating at the same rate. When flows drop to below the pump station capacity, the basin would be pumped to the pump station. Based on storm flow records, the proposed basin would have a 200,000 gallon capacity. Engineer’s estimated cost, for planning comparison - $1,556,900.
This alternative avoids upgrades to the downstream sanitary sewers and provides equalized flows to the South Avenue Lift Station and to the City of Zanesville sewer system. This alternative costs more than Alternative 2 (partly because excavation through shallow hard limestone underlying the project site increases the estimated construction cost significantly) and the basin may be oversized or unnecessary if ongoing I/I reduction efforts minimize flows significantly.
4. Selected Alternative
Both Alternative 2 and Alternative 3 have risk due to uncertainty of effectiveness, which cannot be known until one is operational. The risk that flow equalization may be required to eliminate overflows, as opposed to the risk that the Alternative 3 basin would be oversized, is more acceptable to Muskingum County. Therefore, based on construction cost comparison, relative ease of implementation, and age of the existing pump station, Muskingum County proposes constructing Alternative 2- Increase New Life Lift Station Pumping Capacity (Figure 1).ADD SPACEThe current engineer’s estimated cost is $1,300,000. The proposed project involves construction of:
-a new lift station adjacent to the existing New Life Lift Station – two pumps, instrumentation and controls, new electrical service, and natural gas powered emergency backup pump;
-2,550 feet of 12” diameter sanitary force main, by directional boring;
-1,280 feet of 12” diameter sanitary sewer, by trenching;
-6 manholes;
-appurtenances, connections, electrical and controls; and
-demolition of the existing lift station.
All work will be in previously-disturbed areas along a major road; much of the pipe installation will be by directional boring with no expected surface impact or potential interference with traffic.
5. Project Implementation
Muskingum County advertised for bids in March 2014 for a summer 2014 construction start. The bid has a 90-day acceptance period to allow for completion of funding and other administrative requirements. The contract has a 180-day deadline for substantial completion, meaning the project will be complete and the new pump station and force main operational by late 2014 or early 2015.
The $500,000 special federal appropriation for this project requires a local matching contribution of 45% ($225,000) and is subject to a 3% administration fee ($15,000) leaving a maximum grant value of $485,000 and total value with the local match of $710,000. The local match will be part of the WPCLF loan, which will make up the remainder of the project cost beyond the funds available from the special federal appropriation and the anticipated $100,000 grant from the Appalachian Regional Commission. For this project, Muskingum County qualifies for the small community interest rate for the estimated $815,000 WPCLF loan (currently 2.70% for an April loan award). WPCLF loan interest rates are set monthly and the rate may change for this loan.
Muskingum County anticipates no sewer rate increase in the immediate future.
C. Environmental Impacts of the Proposed Project
This project could directly affect important environmental resources. The project is designed to effectively manage existing flows and anticipated flows from proposed commercial and residential developmentsrather than provide additional capacity in the wastewater system for speculative growth. The proposed developments are subject to the Muskingum County building and zoning review and approval process that minimizes associated indirect or cumulative environmental impacts by requiring compliance with applicable state and / or federal permits, including a storm water permit and water and wastewater authorizations by Ohio EPA or the local water or wastewater agency.
1. Archeological and Historic Preservation Act of 1974, Pub. L. 86-523, as amendedand National Historic Preservation Act of 1966, Pub. L. 89-655, as amended
The Ohio Historic Preservation Office concurred with Ohio EPA’s determination that this project will not cause a significant adverse effect to properties listed or eligible for listing in the National Register of Historic Places.
In the event of archaeological finds during construction, Ohio Revised Code Section 149.53 requires contractors and subcontractors to notify the Ohio Historic Preservation Office of any archaeological discoveries in the project area, and to cooperate with the Office in archaeological and historic surveys and salvage efforts. Work will not resume until a survey of the find and a determination of its value and effect has been made, and Ohio EPA authorizes work to continue.
2. Clean Air Act, Pub. L. 84-159, as amended
Muskingum County air qualitymeets standards for the six regulated air pollutants (carbon monoxide, sulfur dioxide, nitrogen oxide, lead, particulate matter, and ozone). Construction of the proposed replacement lift station and force main is unlikely to add significant pollution to local air because motorized construction equipment will be a minor pollutant source considering the background motorized vehicle exhaust in the greater project area. The operating pump station will be no direct source of air emissions except when the natural gas powered emergency pumps are operating.
During construction, dust and construction vehicle exhaust will be insignificant sources of local air pollution. Dust due to excavation in dry weather will be controlled by good housekeeping measures (minimizing area of disturbed soil, road sweeping, dust suppression with water or other benign dust suppressant). Construction vehicle exhaust will be insignificant compared to background sources of motorized vehicle exhaust in the greater project area. For these reasons, the project should have no significant adverse short-term or long-term impacts on local air quality.
3.Clean Water Act of 1972, Pub. L. 90-500, as amended
This project involves no stream or wetland crossings or filling and will have no direct impact to Waters of the United States. A small stream adjacent to the New Life Lift Station property will be protected from potential runoff of silty storm water from soils exposed for construction by construction best management practices as may be required in a Storm Water Pollution Prevention Plan and Construction Storm Water General NPDES permit (e.g., silt fence, straw bales, and good housekeeping practices).