ENVIRONMENTAL ASSESSMENT

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2 ENVIRONMENTAL ASSESSMENT A. Project Identification Name: Murray City Sewer Facilities Project (CS ) Carbon Hill Sewer Facilities Project (CS ) Address: Hocking County Commissioners 1 East Main Street Logan, OH B. Proposed Project 1. Summary The Hocking County Commissioners has requested financial assistance from the Ohio Water Pollution Control Loan Fund (WPCLF) to install sanitary sewers in Murray City and the unincorporated areas of Carbon Hill, Longstreth, and Candy Town. The proposed sewers will connect to City of Nelsonville sewer system for treatment at the Nelsonville wastewater treatment plant. The project area has significant numbers of failing home sewage treatment systems (HSTS) and sampling by the Hocking County Health Department and Ohio EPA has shown exceedences of safe levels of bacteria in area ditches and streams. Unsanitary conditions and a potential health threat exist throughout the project area. Although Murray City, as an incorporated village, could own and operate a sewer system, collaborating with Hocking County for county ownership of sewers would be less expensive for the village. The WPCLF assistance will be combined with grants from the Ohio Water Development Authority (OWDA) and the Community Development Block Grant (CDBG) program to pay for the $9,000,000 projects. Construction will involve trenching along existing residential streets and rural roads lacking important environmental resources, construction in lawns to install sewer laterals, and crushing and filling existing septic tanks. 2. Project Background a. History and Existing Conditions Ohio EPA stream and ditch sampling in the project area in 2011 confirmed the existence of unsanitary conditions attributed to failing HSTS. Fecal coliform counts above 5,000 per liter of water constitute a public health nuisance. Ohio EPA sampling found fecal coliform counts as high as 180,000 (Figure 1). On each of the four sampling dates, at least one sampling location exceeded the public health nuisance level. Small residential lots with soils unsuited to HSTS preclude replacing the failing systems. Environmental Assessment Hocking County Murray City and Carbon Hill Sewer Facilities 1

3 Figure 1 - Ohio EPA Sampling Results Concurrently with Hocking County s development of these projects, the City of Nelsonville has planned the replacement of its aged, undersized, and deteriorating municipal wastewater treatment plant (WWTP). Ohio EPA considers the WWTP to be in significant noncompliance with its National Pollutant Discharge Elimination System (NPDES) permit. Nelsonville is collaborating with the Hocking County Commissioners, the Athens County Commissioners, the Village of Murray City, and the Village of Buchtel to become a regional treatment provider for the area and is designing a larger WWTP at a new location. b. Population and Flow Projections The project service area includes approximately 330 occupied structures and 870 people. The estimated average daily flow (ADF) for design purposes is approximately 55,000 gallons per day (gpd); peak flow is 220,000 gpd. The population of the project area has been stable or declining; no significant growth is expected. The 520,000 gpd capacity of the pipes to be installed is adequate to accommodate modest growth. Environmental Assessment Hocking County Murray City and Carbon Hill Sewer Facilities 2

4 c. Water Quality The streams near the project area are Monday Creek, its tributary Snow Fork Creek, and lesser tributary streams of the Hocking River. The Monday Creek watershed is significantly affected by acid mine drainage from the region s legacy of coal mining. Snow Fork Creek, which passes through Murray City and which drains the eastern part of the project area, is impacted by acid mine drainage and classified as a Limited Resource Water (LRW) in the Ohio Water Quality Standards. Although Murray City lacks sanitary sewers, four stormwater pipes that carry drainage water contaminated by failing HSTS outfall to Snow Fork Creek as combined sewers. Snow Fork and tributaries have public health nuisance levels of fecal coliform bacteria. The mainstem of Monday Creek, which is designated Warmwater Habitat (WWH), flows southeastward through the Carbon Hill portion of the project area and is also affected by acid mine drainage and failing HSTS. 3. Discussion of Feasible Alternatives The potential human health threat of raw sewage in the environment means doing nothing, the no-action alternative, is not feasible. A lack of action by Hocking County could lead to Ohio EPA requiring elimination of the unsanitary conditions. Feasible sewer alternatives evaluated in a 2015 planning document for unsewered areas of Hocking County include: conventional gravity sewers (estimated cost of $1,514,000; these numbers were derived for planning comparisons and may not reflect actual costs) septic tank effluent pump (STEP) system (estimated cost of $2,045,000) vacuum collection system (estimated cost of $2,459,000); and small-diameter collection system (estimated cost of $1,709,000). Feasible wastewater treatment alternatives evaluated include: discharge to an existing sewer for treatment at an existing WWTP (estimated cost of $0; using an existing facility eliminates the cost of constructing a new facility) construction of a local WWTP (estimated cost of $1,230,000); and cluster treatment system (constructing several small treatment systems in the project area). Because a cluster system would be more suited for a new development where land is available, this alternative was deleted from consideration. Conventional gravity sewers are simple and common, typically consisting of 8 diameter polyvinyl chloride pipe installed at constant slope to allow gravity to carry sewer flows from homes to a WWTP or pump station with a pressurized pipe to move sewer flows farther in the system or to a WWTP. In hilly areas such as this project area, gravity Environmental Assessment Hocking County Murray City and Carbon Hill Sewer Facilities 3

5 sewers typically require one or more pump stations. Gravity sewers require deeper excavations to maintain the constant slope. A gravity system without pump stations and force mains requires no power source or mechanical equipment requiring routine maintenance. STEP systems rely on a new septic tank with a pump at each residence or occupied structure to remove the liquid portion of sewage while solids remain in the tank. The pump forces the septic tank effluent through a small diameter pipe to a larger, pressurized pipe and eventually to a gravity sewer or pump station. STEP systems require regular maintenance and periodic pump replacement, an electrical connection, and regular septic tank pumping to remove solids that otherwise would clog pumps. STEP systems cost less to install than gravity sewers because pipes are smaller and can be shallower, although they have higher operation and maintenance costs than gravity sewers. Vacuum sewers are small-diameter pipes connected to a holding tank with a one-way valve at each residence or other building. A central vacuum station maintains a constant negative pressure in the system and when sufficient wastewater accumulates in the holding tank the valve opens and the tank contents are pulled into the vacuum sewer and toward the vacuum station where the sewage enters a gravity sewer or pump station. Because the pipes are pressurized, they can be installed in shallower trenches than gravity sewers. However, the system also requires a vacuum station building and the vacuum equipment which requires a constant source of electricity and regular maintenance and repair or replacement. Small-diameter collection systems are similar to STEP systems without the pumps. Septic tank effluent flows by gravity into a small-diameter gravity sewer, which can be a smaller diameter than a gravity sewer because it carries only liquids and no solids. Septic tanks must be regularly pumped to avoid entry of solids into the small-diameter sewers. Pipes must be laid on a constant slope to ensure proper flow and may require pump stations. 4. Selected Alternative Based on construction costs, operation and maintenance (O&M) costs, and project area realities of lot sizes and density of residential areas, Hocking County proposes constructing conventional gravity sewers with pump stations and force mains to allow the elimination of failing HSTS that cause unsanitary conditions in Murray City, Carbon Hill, and surrounding areas. The Murray City and Carbon Hill projects will involve construction of approximately 30,750 linear feet (LF) of 8 diameter gravity sewer; 48,000 LF of force main; 5 pump stations; 327 lateral connections; and associated manholes in and along public road rights-of-way to serve Murray City, Carbon Hill, Candy Town, and Longstreth (Figure 2). The new sewer system will connect into existing sewers in the Village of Buchtel that Environmental Assessment Hocking County Murray City and Carbon Hill Sewer Facilities 4

6 drain to Nelsonville s wastewater treatment plant. Most sewer installation will be completed by open-cut excavation. Horizontal directional drilling (HDD) will be used for stream crossings to avoid disturbance to surface water resources. Because HDD can release clay-based lubricant to the surface, the contract requires contractors to prepare a contingency plan for prompt clean-up in case of a release of the drilling fluid. After installation of the public sanitary sewer infrastructure, each property owner will be required to construct a sanitary sewer lateral connecting their residence or other occupied structure to the new sewer and remove or crush and fill each existing HSTS. The costs of installing the lateral from the home to the new sewer and of abandoning the HSTS are the responsibility of each property owner. Project funding includes $200,000 of Community Development Block Grant assistance available to incomequalified owners to assist with those on-lot costs. Figure 2 Project Locations Environmental Assessment Hocking County Murray City and Carbon Hill Sewer Facilities 5

7 5. Project Implementation Assuming loan award in September 2018, construction will begin in late 2018 and be completed by early Sewer flows in the new system will increase gradually as buildings are connected according to the Hocking County Health Department s schedule. These new flows will be treated at the existing Nelsonville WWTP until the new WWTP is operational. Hocking County has received a $500,000 grant from the Ohio Water Development Authority (OWDA) for each project ($1,000,000 total) and a $750,000 grant from the Community Development Block Grant (CDBG) program for each project ($1,500,000 total). These funds will be combined with a total of $3,563,560 for both projects of Principal Forgiveness funds (loan that is not repaid) from the WPCLF and $3,000,000 of WPCLF 0% Hardship, 30-year interest rate loan. During the 30-year loan period, Hocking County will save approximately $9,800,000 by using WPCLF dollars at this rate and with Principal Forgiveness, compared to the market rate of 3.48%. C. Environmental Impacts of the Proposed Project This project could directly affect environmental features. Because the project is designed to provide sanitary sewer service to a developed area rather than provide additional capacity in the wastewater system for growth and is in an area with limited potential for residential or economic growth, the project is not expected to lead to new development or associated indirect or cumulative impacts. Because all work will be in and adjacent to existing roads and short easements in developed residential areas lacking important environmental features, construction will have no effect on major land forms, wetlands, floodplains, agriculture or land use, or ground water resources. Local surface water resources will be protected by use of standard construction soil erosion control measures. While most of the sewers will be constructed by open-trench excavation, spans beneath streams will be constructed by horizontal directional drilling to avoid direct impacts to aquatic habitats. To help minimize potential impacts to streams in the unlikely event of a release of clay-based drilling fluid, the contract requires a contingency plan be in place to remove or remediate any drilling fluid that reaches the surface. Although this project requires little vegetation clearing, because the greater project area is known habitat for the endangered Indiana bat and threatened northern long-eared bat, trees will be removed only between November 15 and March 15 when the bats are unlikely to be present. Because no other listed species or habitat are in the project area, this tree-clearing restriction avoids adverse impacts to important terrestrial habitats. The gravity sewers have no energy requirements or sources of air pollution beyond temporary construction-related vehicle exhaust. No significant adverse short- or long- Environmental Assessment Hocking County Murray City and Carbon Hill Sewer Facilities 6

8 term impacts to noise levels, traffic, safety, or aesthetics are expected due to this project. Construction vehicle noise will be audible during construction, limited to daylight hours and similar to that of normal traffic sounds. Traffic disruption will be minimized by standard construction traffic maintenance measures, including barrels, flaggers, and temporary detours. Public safety will be assured by traffic controls and by filling or covering trenches at the end of each work day. Local aesthetics will be unaffected by the project after road and landscape restoration is complete; residents may be aware of the absence of septic odors once the sewers are operational and failing septic systems are abandoned. There is no evidence of important cultural resources in the project disturbance area. The Ohio State Historic Preservation Office concurred with Ohio EPA s conclusion that the project will have no adverse effect on historic or archaeological resources. In the event of archaeological finds during construction, Ohio Revised Code Section requires contractors and subcontractors to notify the State 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 when appropriate. 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. Hocking County minimized the project cost by receiving significant grants, principal forgiveness loans, and 0% interest loans. This allows a lower annual sewer bill for the new customers than would otherwise be possible. On-lot costs (construction of sanitary sewer laterals and abandonment of HSTS) are approximately $3,000-$5,000, and Community Development Block Grant assistance is available to subsidize those costs for qualifying homeowners. The expected annual sewer bill will be approximately $540, which is 1.6% of local median household income (MHI) of $33,562 for Murray City (assume equivalent for the Carbon Hill area) and compares favorably to the Ohio average annual bill of $661. Sewer bills less than 1.8% of MHI are generally considered affordable. By using the WPCLF low-interest financing with principal forgiveness and other grant funds for this project, Hocking County has minimized the cost and the economic impact on customers and the local economy. D. Public Participation The history of failing HSTS and attention by Ohio EPA and the Hocking County Health Department have kept visible the prospect of sewer service in the project areas. News outlets have covered progress through 2017 and in The CDBG program requires two formal public events to present project information to the public. These meetings for the Carbon Hill and Murray City projects were held in March and April 2018 with 62 total attendees. Ohio EPA will make a copy of this document available to the public on its web page Environmental Assessment Hocking County Murray City and Carbon Hill Sewer Facilities 7

9 ( WPCLF Documents for Review and Comment) and will provide it upon request. E. Reasons for a Preliminary Finding of No Significant Impact Based on its review of this project s general plans and other information, Ohio EPA concludes that no significant short-term or long-term adverse direct environmental impacts will result from the project as related to the environmental features discussed in this Environmental Assessment. This is because these features do not exist in the project area, the features exist but will not be adversely affected, or the impacts of construction will be temporary and mitigated. This project equally serves the entire project area and no particular segment of the community will be faced with additional adverse impacts or be deprived of environmental benefits, compared to any other segment. For these reasons, this project, alone or in combination with other projects, is not expected to result in any significant indirect or cumulative short-term or long-term adverse environmental impacts. Ohio EPA expects the economic impact of the project on the average user to be acceptable because of the significant grant and principal forgiveness loan assistance that minimize the overall cost. The project will eliminate the documented public health threat of failing home sewage treatment systems. For more information, please contact: Dan Halterman Ohio EPA DEFA-OFA P.O. Box 1049 Columbus, OH (614) daniel.halterman@epa.ohio.gov Environmental Assessment Hocking County Murray City and Carbon Hill Sewer Facilities 8