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HomeMy WebLinkAbout20200405 Ver 1_Appendix D_Record of Decision_20200325 Appendix D Record of Decision REVISED RECORD OF DECISION STOWE REGIONAL WATER RESOURCE RECOVERY FACILITY (formerly known as the Long Creek Regional Wastewater Treatment Plant) CHARLOTTE WATER/CITY OF MOUNT HOLLY/CITY OF BELMONT MECKLENBURG AND GASTON COUNTIES, NORTH CAROLINA DEQ#1603; DENR#1597 PREPARED BY: NORTH CAROLINA DEPARTMENT OF ENVIRONMENTAL QUALITY DIVISION OF WATER RESOURCES January 2, 2020 (Replaces the approved March 18, 2015 version) CONTACT PERSON: David Wainwright NCDEQ, Division of Water Resources Mail Service Center 1611 Raleigh, NC 27699-1611 (919)707-9045 David.Wainwright@ncdenr.gov REVISED -Record of Decision — Charlotte -Mecklenburg Utilities/City of Mount Holly Regional Wastewater Treatment REVISION NOTE Prior to construction of the proposed project, the applicant contacted the DWR regarding a few minor changes to the project. Changes include the location of an equalization basin and new access and construction roads. The preferred alternative has not changed and remains alternative 2. The applicant has submitted documentation to the Division dated December 20, 2019, with the subject line of "Charlotte - Mecklenburg Utilities/City of Mount Holy+/City of Belmont Regional Wastewater Treatment Final Environmental Impact Statement Revision Letter" which outlines proposed changes to the project and are addressed in this revised ROD. Proposed revisions are only to occur' at the current Long Creek Pump Station site. Proposed project revisions will include additional impacts to wetlands, prime and unique farmlands, and floodplains; but all will be minor or negligible impacts. Bridges over Long Creek will result in minor impacts to wetlands (less than 0.1 acre) and potentially minor or negligible impacts to floodways. Clearing of land will increase (approximately 4.5 acres for temporary construction access, approximately 8.5 acres for a permanent access road, and approximately 20 acres for the equalization basin). Much of these lands are considered prime and unique farmlands or farmland of statewide importance. However, these areas are forested and not currently being farmed, are zoned either industrial or single family residential, and are owned by the City of Charlotte. Due to these conditions, impacts to prime and unique farmlands is considered minimal. Due to the additional clearing, impacts to land cover will occur. Wildlife may be impacted by the additional clearing, but much of the surrounding area will still be forested and it is therefore expected that wildlife will relocate to those areas. The proposed changes will impact the Thread Trail (used for walking, hiking, and mountain biking). Impacted portions of the will be relocated within the remaining 85-acre forested track, thereby mitigating additional impacts to public lands, scenic, and recreational areas. No additional impacts rp areas of archeological or historical value; rare or protected species; air quality; noise; water resources, shellfish, and their habitats; water quality; soils; ground water; water supply; or impacts from toxic substances are anticipated. SUMMARY An EIS has been prepared for the Charlotte -Mecklenburg Utilities Department (CMUD) and the planned wastewater treatment expansion for the existing service area as well as surrounding service areas. The proposal considers wastewater treatment at a regional level and includes the City of Mount Holly, the City of Belmont, Clariant Corporation (Clariant), and CMUD's western Mecklenburg County wastewater service area. A feasibility study was performed in 2006 for CMUD and the City of Mount Holly to identify potential alternatives to meet the needs of the projected growth in the service areas. Study results recommended a regional approach, and that is what is being pursued by CMUD and the City of Mount Holly. As discussed in the EIS, there has been extensive stakeholder involvement with the public and private sector as well as government officials throughout project development. The preferred alternative would include constructing a new Wastewater Treatment Plant (WWTP) facility on the Mecklenburg County side of the Catawba River on land near the existing Long Creek pump station. The new facility would treat wastewater from both CMUD and the City of Mount Holly. Flows from the City of Mount Holly and the City of Belmont would be pumped under the Catawba River to the new facility. REVISED -Record of Decision —Charlotte-Mecklenburg Utilities/City of Mount Holly Regional Wastewater Treatment A new force main would be constructed from the City of Belmont WWTP to the Paw Creek lift station. The existing Long Creek pump station would be modified to serve as the influent pumping station for the new facility. PURPOSE AND NEED The purpose of the proposed project is to address future wastewater demands in northwestern Mecklenburg and eastern Gaston Counties. Populations in these areas are expected to grow considerably by 2030. Population growth in the CMUD service area, which includes the Long Creek Basin, Paw Creek Basin, Catawba Creek Basin, Gar Creek Basin, and the Lower Mountain Island Lake Basin, is expected to increase from 43,371 in 2010 to 1 15,580 in 2030. Consequently, wastewater flows in the service area is expected to increase from 6.44 million gallons per day (mgd) in 2010 to 14.74 mgd in 2030. In order to meet the needs of these growing areas, without hindering growth, the wastewater capacity of the region will need to be increased. ALTERNATIVES ANALYSIS Several alternatives were identified dwing the planning process. A total of seven alternatives were carried forward and considered in the EIS; the EIS provides a full discussion of these alternatives. A brief statement on each is below: No Action: The No Action Alternative does not include construction of a new wastewater Geatment plant or other associated infrastructure. However, based on a NCDENR requirement, this alternative would include upgrading the existing City of Mount Holly WWTP (Mount Holly WWTP) and City of Belmont WWTP (Belmont WWTP). Wastewater from the Long Creek basin would continue to be piped over 20 miles to the McAlpine Creek Wastewater Management Facility (WWMF). The Mount Holly WWTP is approaching its maximum design capacity. Without expansion, areas not currently serviced would likely have to utilize onsite septic systems. 2. Operate ,Tointly at New Reeional WWTP in Mount Holly (Alternative 1): This alternative consists of constructing a new WWTP facility on land adjacent to the existing Mount Holly WWTP site. This new plant would serve the City of Mount Holly as well as CMUD. The Belmont WWTP would be decommissioned and replaced with a new pump station. A new force main would be constructed from the Belmont WWTP to the Paw Creek lift station. Wastewater From Long Creek would be pumped across the Catawba River to the new facility. A portion of the wastewater may be treated for reuse or reclaimed purposes such as landscape irrigation and industrial purposes. 3. Operate Jointly at New Reeional WWTP in Mecklenburg County near Lone Creek (Alternative 2—Preferred Alternative): Under this alternative, a new WWTP facility would be constructed on the Mecklenburg County side of the Catawba River on land near the existing Long Creek Pump Station. The new facility would treat wastewater from both CMUD and the City of Mount Holly. Flows from the City of Mount Holly and/or City of Belmont would be pumped under the Catawba River to the new facility. A new force main would be constructed from the Belmont WWTP to the Paw Creek lift station. The existing Long Creek pump station would be modified to serve as the influent pumping station for the new facility. A portion of the wastewater may be treated for reuse or reclaimed purposes such as landscape irrigation and industrial purposes. REVISED -Record of Decision —Charlotte-Mecklenburg Utilities/City of Mount Holly Regional Wastewater Treatment 4. Non-Discharge/Land Application Alternative: State law requires land application to be considered for any WWTP. This option was found to be technically and economically infeasible due to the large amount of land that would be required. Based on calculations, necessary land requirements would be between 37 and 230 acres for non -discharge ponds and storage and between 1,000 acres and 13,000 acres for land application. In an urban setting these land requirements would be difficult to achieve and the cost to purchase suitable land would be prohibitive. PREFERED ALTERNATIVE Alternative 2, operate jointly at a new regional WWTP on the Mecklenburg County side of the Catawba River near Long Creek, was chosen as the preferred alternative. This alternative was selected over the others because it meets the developing region's need for additional wastewater treatment capacity and results in a combination of fewer negative environmental consequences. These include comparatively fewer natural resource and environmental impacts at the building site; fewer construction and operational constraints; greater public recreation and open space benefits; reduced energy use; increased water volume in Lake Wylie for local uses such as power generation, cooling water, low flow supplementation, and drinking water; and concurrence with the planning goals of the affected local governments. Additionally, the placement of a single W WTP is preferable to other alternatives in terms of compatibility with existing and future land uses, protection of riparian buffers, and reduced impacts to critical areas such as streams and wetlands. Advanced treatment at a new facility would produce high quality effluent with low nutrient concentrations and provide additional water into Lake Wylie for many beneficial uses. The Preferred Alternative also provides regional wastewater treatment with a single discharge that promotes efficient planning, design, and permitting; minimizes shoreline and wetland impacts; and cost-effectively achieves project goals. It also has the potential to eliminate three existing discharges and reduce the risk of overflows by reducing wastewater pumping distance. F,NVIRONMENTAL IMPACTS All means of avoiding or minimizing environmental and cultural impacts outlined in the EIS will be incorporated into the project. Moreover, the project will be designed and constructed to avoid adverse mpacts to existing environmental features as much as practicable. A summary of impacts to environmental features and mitigative actions for the preferred alternative is described below: Topography and soils: There will not be significant long-term impacts as a result of the project. Impacts include those associated with leveling, excavation, and grading from construction of the project Much of the preferred alternative would occur on land that has been previously disturbed. Impacts to soils and soil loss would be controlled through the use of appropriate Best Management Practices (BMPS). Land Cover and Land Use: The new facility constructed under the preferred alternative would be located on land currently zoned industrial and the Belmont pump station and face main would be constructed on previously disturbed land. With the preferred alternative, there would be approximately 85-acres of undisturbed forested lands adjacent to the National Whitewater Center that could be used for public uses such as greenways or other recreational activities. Impacts to the Thread Trail would be mitigated by relocating affected trail portions within the remaining forested tract adjacent to the project. REVISED -Record of Decision —Charlotte-Mecklenburg Utilities/City of Mount Holly Regional Wastewater Treatment Wetlands and Floodplains: Force mains would cross the Catawba River, Paw Creek, and Long Creek. These crossings would be within the floodplain and associated wetland areas. Force mains and outfall structure would be directionally bored, eliminating direct impacts to wetlands. The outfall would be constructed within the Catawba River floodplain but will not result in an increase in the 100-year flood base flood elevation. Impacts from access road bridges over Long Creek will minimize impacts to wetlands and floodplains but will still result in unavoidable but minimal impacts to wetlands and floodplains. Water Quality: Impacts to surface waters include those from stormwater runoff, riparian buffer impacts, and wastewater effluent. Increases in stormwater runoff may affect aquatic resources. The project will require a Stormwater Pollution Prevention Plan (SWPPP); the included guidelines will minimize and reduce the number and amount of pollutants leaving the site through BMPs. Riparian buffer areas may be affected by force main and outfall crossings. Impacts to these areas will be minimized through the use of directional boring under streams and associated riparian areas. Additionally, proposed facilities will be located outside of riparian buffer areas. Wastewater discharge to Lake Wylie will increase. Compliance with all NPDES permit limits will be required. Ground Water: No direct impacts to groundwater are expected. Water Supply: The proposed project will increase the amount of wastewater being discharged into Lake Wylie. NPDES permit limits will protect the quality of water which will not exceed drinking water standards. Wildlife and Aquatic Resource Habitats: Impacts to terrestrial species is expected to be limited to those areas that will be cleared; impacted wildlife may move to adjacent forested areas. Impacts to aquatic species are expected to be minimal due to stormwater controls and stringent NPDES discharge limits. Rare and Protected Species: The preferred alternative will not impact any rare or protected species. Public, Scenic, and Recreational Areas: A portion of the proposed project is in close proximity to the National Whitewater Center. The proposed alternative would preserve an approximately 85-acre tract adjacent to the National Whitewater Center which could be used to provide additional hiking and biking trails as well as a new canoe launch on Long Creek. Potential adverse impacts include odors and wastewater spills, which could result in disruption of recreational activities. New facilities would be designed to prevent storm -flow bypasses and sanitary sewer overflows. Odor control technology would be incorporated into the project as well. Impacts to the Thread Trail would be mitigated by relocating affected trail portions within the remaining forested tract adjacent to the project. Energy Resources: Energy consumption would increase as the new facility comes online, but usage would partially be offset by not having to pump wastewater from Long Creek pumping station to McAlpine Creek W WTP. Additional water volume in Lake Wylie could potentially be used for additional power generation, and it may be possible to use onsite generated methane to partially power the facility and reduce the consumption of natural gas. Archeological or Historical Resources: There are no properties registered on the National Sate Register of Historic Places. State Historic Preservation Office correspondence states that they will not require any archeological surveys. Prime Agricultural Lands: Construction of the equalization basin, access roads, and temporary construction access roads will result in impacts to prime agricultural lands. However, the affected lands are currently forested and not being used for agriculture, are zoned industrial and single residence, and are owned by the REVISED - Record of Decision — Charlotte -Mecklenburg Utilities/City of Mount Holly Regional Wastewater Treatment City of Charlotte. Since the City of Charlotte has no intent to sell or farm the land, and based on current zoning, impacts are deemed minimal. Air Quality: Direct impacts to air quality will be temporary and minor. During construction, dust control measures will be employed to limit dust exposure in the project area. Operation of the plant will not produce any regulated air quality contaminants. Nearby residences and businesses would be buffered by forested areas surrounding the facility. An air quality permit would be required for the operation of the back-up generators and methane gas produced onsite would likely be used to generate power for the facility. Nuisance Conditions: Temporary uoise and dust will be generated as result of construction. Odor conG'ol measures would be used at the plant and pumping station. Most equipment would be housed in buildings which will also help reduce noise and odors. A forested buffer around the facility will also help alleviate potential noise and odor concerns. Toxic Substances: Toxic substances will not be inu'oduced during construction. All chemical storage and feed areas at the plant would be provided with secondary containment. Onsite diesel fuel tanks for generators will have secondary containment and leak detection systems. SECONDARY AND CUMULATIVE IMPACTS The secondary and cumulative impacts associated with the preferred alternative would generally be related to continued urban growth and land use changes associated with population increases in the service area. It is expected that population increases and associated secondary and cumulative impacts would occur regardless of whether or not the proposed project is constructed. The Gar and Catawba Sub -basins and portions of the Mountain Island Lake Sub -basin currently utilize onsite septic tanks. The preferred alternative may allow these areas to be serviced with the wastewater facility which would help eliminate the effects of failing septic sewer systems. If these areas were to be serviced by the new facility, it would allow higher density development than what currently exists in these areas. This may allow these areas to have more development due to higher density than would be seen if the area remained on individual septic systems. Growth would continue in other areas of the service areas as well. Several local and State regulations are in place throughout the project service area that will minimize secondary and cumulative impacts and include various zoning restrictions, Water Supply Watershed Protection areas, stormwater BMPS and regulations, riparian buffer rules, NPDES permitting, floodplain protection ordnances, and municipal separate storm sewer systems (MS4). Public sewer extension projects would be required to apply for and obtain the necessary permits and evaluate, avoid, and minimize environmental impacts. Water supply watershed protection rules, which limit land use densities and apply other development restrictions to protect water quality, apply to a large portion of the project service area in both Gaston and Mecklenburg Counties. Additionally, a number of local policies and ordinances are in place that would further limit secondary and cumulative impacts. Beneficial impacts of the proposed project may also Deco. By relocating the discharge point from Long Creek to Lake Wylie, energy currently being used to pump wastewater 20 miles will be saved. The additional discharge into Lake Wylie could be used to produce additional electricity. While some of the treated effluent would be used onsite as reclaimed water, there exists the possibility that the reclaimed water F7 REVISED - Record of Decision — Charlotte -Mecklenburg Utilities/City of Mount Holly Regional Wastewater Treatment program could be expanded to include industrial and/or landscape applications, which could, in turn, reduce the demand for treated drinking water during peak and drought conditions. NECESSARY ACTIONS It is ant cipated that the project will require the following actions: • NPDES Permit • FERC Permit • Air Quality Permit • Dam Permit (for Equalization Basin embankment) • 401 Water Quality Certification • 404 Clean Water Act Permit • Erosion Control Permit • Mecklenburg County Building Permit • Authorization to Construct EIS REVIEW AND COMMENT The EIS has been properly advertised and reviewed by State and Fedora] agencies. Extensive public input has been made into the planning process. Comments from agencies and citizens have been incorporated into the proposed project. A copy of this Revised Record of Decision will be sent to the Clearinghouse, all review agencies, and a notice of its availability will be published in the Environmental Bulletin. L tda Culpepper (Date) Director, Division of Water Resources