City of Mt. Shasta Sewer Line Improvements Project Roles of Team CITY OF Mt. Shasta CALIFORNIA City of Mt. Shasta – CEQA Lead Agency • Point of contact for the public • Adoption of the EIR under CEQA • Approval of project Pace Engineering, Inc. – Engineering Consultant • Screening of alternatives and construction methodologies • Project design North State Resources, Inc. North State Resources, Inc. – Environmental Consultant • Completion of supporting technical studies • Facilitation of public outreach/scoping process • Preparation of the EIR under direction of the City CITY OF Mt. Shasta CALIFORNIA City of Mt. Shasta Sewer Line Improvements Project CEQA Process The California Environmental Quality Act California Environmental Quality Act (CEQA) – CEQA requires that California state and local agencies prepare an Environmental Impact Report (EIR) when they determine the project may have a significant impact on the environment EIR - An EIR is a public document that provides an assessment of the potential environmental impacts resulting from a proposed project and alternatives. Within the EIR, the potentially affected environmental setting is identified and resources potentially impacted are analyzed. Analysis – Major resource areas to be evaluated in the EIR include, but are not limited to: • • • • • • • • • • • Aesthetics Biological resources Cultural resources Groundwater Land use Hydrology and water quality Air quality Noise Hazardous materials and hazardous waste Traffic Cumulative Impacts EIR Public Involvement Opportunities During the CEQA Process Notice of Preparation Attend the Public Scoping Meeting in Mt. Shasta, CA – November 12, 2014 Scoping Review and Comment on the Draft EIR – Summer 2015 Draft EIR • Availability of the Draft EIR will be announced in the local newspaper and on the City’s website Public and Agency Review • The 45-day comment period commences with the availability of the announcement State Clearinghouse Review Final EIR Review of Responses by Commenting Agencies Agency Discussion Findings; Statement of Overriding Considerations; Mitigation Monitoring Program Attend the Public Hearing on Draft EIR – Fall 2015 – Winter 2015 • Notice of the hearing will be announced in the local newspaper and on the City’s website Attend Public Hearing on the Final EIR • Notice of the hearing will be announced in the local newspaper and on the City’s website While it is the goal of the project team to meet these dates, all dates references are tentative and may be adjusted as circumstances dictate during the EIR process. CITY OF Mt. Shasta CALIFORNIA City of Mt. Shasta Water and Wastewater Facility Improvement Project Key Environmental Issues Air Quality • Fugitive dust generated by construction activities, including vehicle travel over unpaved roads • Exhaust emissions from construction equipment and worker commute and delivery vehicles • Contribution to greenhouse gas emissions (construction and operational) Cultural Resources • Sensitivity for historic and prehistoric resources within the project study area • Potential for discovery of prehistoric resources during ground-disturbing activities Hydrology and Water Quality • Short-term sedimentation and turbidity within Cold Creek, a tributary to the Sacramento River, as a result of erosion during construction • Excavation activities has the potential to perch groundwater, which would require dewatering Wetlands and Biological Resources • Temporary and permanent effects to jurisdictional waters and riparian vegetation • Potential effects on special-status species and associated habitat –– Little willow flycatcher –– Greater sandhill crane –– Yellow warbler/yellow-breasted chat –– Cascade frog/foothill yellow-legged frog –– Alepo avens Hazards/Hazardous Materials • Accidental spills from construction equipment and/or vehicles • Potential for wild land fire CITY OF Mt. Shasta CALIFORNIA City of Mt. Shasta Water and Wastewater Facility Improvement Project Key Environmental Issues Aesthetics • Temporary disruption of area view shed due to presence of construction equipment in open space areas • Short-term disturbance to open space areas following construction and prior to revegetation Land Use • Consistency with local land use plans, policies, and deed restrictions associated with an established mitigation area • Temporary conflicts with existing land uses and during construction Noise • Short-term disturbance to adjacent residents during construction of the proposed sewer line • Consistency with the City’s local noise policy Cumulative Impacts • City’s Wastewater Treatment and Disposal Feasibility Study to comply with State Mandated NPDES permit and new ammonia levels • Relationship to proposed operations at the Crystal Geyser Bottling Facility –– Truck traffic along existing local roads –– Air quality associated with operation/truck traffic –– Noise associated with operation/truck traffic –– Effects of pumping activities on local aquifer and groundwater levels of local residential wells –– Potential changes in effluent quality associated with discharge of effluent from the Crystal Geyser Bottling Facility into the City’s sewer system CITY OF Mt. Shasta CALIFORNIA City of Mt. Shasta Sewer Line Improvements Project Proposed Project Layout Replace sanitary sewer in place in same easement (open cut) (east) Sanitary sewer to be abandoned (east) Sanitary sewer (open cut) north Potential construction staging area Sanitary sewer trenchless Potential access road Replace sanitary sewer in same easement (open cut) (east) CITY OF Mt. Shasta CALIFORNIA City of Mt. Shasta Sewer Line Improvements Project Alternative 1 CITY OF Mt. Shasta CALIFORNIA • Alternative 1 would replace the majority of existing interceptor within existing easements, including the portion across the wetlands parcel. • Alternative 1 would have the greatest impact to wetlands because open-cut trenching would need to occur within the wetlands (Photo 1A). Some of the impact could be mitigated by using trackmounted equipment and temporary road mats in travel areas. However, due to the status of the parcel having conservation easement restrictions, Alternative 1 may not be possible to permit and construct. • The wet, unstable soil through the wetlands would be difficult to brace and shore for keeping construction workers safe (Photo 1B). Replace sanitary sewer in same easement (open cut) (east) Bore and jack sanitary sewer (north) Replace sanitary sewer in same easement (open cut) (east) Replace sanitary sewer in same easement (open cut) (east) Potential construction staging area Potential access road • The portion of interceptor south of South Old Stage Road would be replaced using open-cut, excluding the portion south of Ream Avenue, which would utilize Horizontal Directional Drilling (HDD) due to the large culvert conveying the unnamed drainage tributary to Cold Creek. There may be a couple of additional reaches crossing wetlands that we may utilize HDD (Photos 1C and 1D). Photo Alternative 1A Typical open-cut trench installation Photo Alternative 1B Open-cut sewer installation inside a shoring shield, under normal trenching conditions Alternative 1 Photo Alternative 1C Typical open-cut sewer installation using excavators and shoring shield Photo Alternative 1D Typical open-cut sewer installation using excavators and shoring shield CITY OF City of Mt. Shasta Sewer Line Improvements Project Mt. Shasta CALIFORNIA Alternative 2 • Alternative 2 would utilize HDD to replace the portion of the interceptor across the wetlands parcel. This approach would significantly reduce the impacts to existing wetlands because HDD is a “trenchless” installation technique (Photo 2A and 2B). • The HDD process, particularly with the diameter and lengths being considered, requires a relatively straight alignment between drilling and receiving pits. This makes pulling the new pipeline back through the drilled hole easier. As such, it will be necessary to establish a new alignment across the wetlands parcel. • It will be necessary to install one manhole near the center of the HDD pipeline, which will require vehicular access across the property through wetlands. Thus, there will be some impacts that will be mitigated by using temporary road swamp mats when traversing across wetlands to the upland area near the proposed manhole (Photo 2C). Replace sanitary sewer in place in same easement (open cut) (east) Sanitary sewer to be abandoned (east) Sanitary sewer (open cut) (north) Potential construction staging area Sanitary sewer (trenchless) (north) Replace sanitary sewer in easement (open cut) (east) Potential access road • It will be necessary to obtain new easements from the property owner and “quit-claim” back existing easements. • The portion of interceptor south of South Old Stage Road will be constructed similar to Alternative 1. Photo Alternative 2A Typical HDD installation showing the pipe pull Alternative 2 Photo Alternative 2B Typical HDD installation showing the drill rig (note: HDD pipe shown is smaller than what is being proposed for this project) Photo Alternative 2C Example of temporary road swamp map CITY OF City of Mt. Shasta Sewer Line Improvements Project Mt. Shasta CALIFORNIA Alternative 3 • Alternative 3 eliminates the need to replace a large portion of interceptor across the wetlands parcel by installing a new sewage lift station near the intersection of West Jessie Street and Hatchery Lane near the I-5 interchange (Photo 3A). • A pressurized raw sewage force main would be constructed west along Hatchery Lane, and then south along South Old Stage Road, discharging to a manhole in South Old Stage Road. • Since the City has no other raw sewage lift stations in its collection system, a new lift station presents operational and maintenance challenges for City staff. This would increase on-going O&M costs for the City. Replace sanitary sewer in place in same easement (open cut) (east) Sanitary sewer to be abandoned Sanitary sewer (open cut) (north) Sanitary sewer lift station (north) Replace sanitary sewer in same easement (open cut) (east) Sanitary sewer force main (open cut) (north) • The lift station would increase electrical power consumption and lead to increased O&M costs. • The portion of interceptor south of South Old Stage Road will be constructed similar to Alternative 1. Alternative 3 Photo Alternative 3A Typical submersible-type sewage lift station CITY OF City of Mt. Shasta Sewer Line Improvements Project Mt. Shasta CALIFORNIA Alternative 4 • Alternative 4 is similar to Alternative 3 in that constructing a new interceptor across the wetlands parcel is eliminated. The alternative consists of constructing a gravity sewer west along Hatchery Lane, then south along South Old Stage Road to the current alignment. • Due to the increase in length between West Jessie/Hatchery Lane and the existing alignment on South Old Stage Road, a new gravity interceptor would be much deeper (by approximately 20 feet) than the existing pipeline. This will require deepening the downstream interceptor for a considerable distance, leading to higher costs. Replace sanitary sewer in place in same easement (open cut) (east) Sanitary sewer (open cut) (north) Sanitary sewer (open cut) (north) Replace sanitary sewer in same easement (open cut) (east) • Portions of the new interceptor along South Old Stage Road would be about 20 feet deep, which is difficult and very expensive to construct. Future O&M is also challenging. • The portion of interceptor south of South Old Stage Road will be constructed similar to Alternative 1, except a significant portion would be much deeper to account for the longer upstream alignment. Alternative 4 CITY OF City of Mt. Shasta Sewer Line Improvements Project Mt. Shasta CALIFORNIA Alternative 5 • Alternative 5 eliminates the need to install a new interceptor across the wetlands property, except that a small diameter pipeline would be pushed through the existing interceptor pipe in order to serve the existing services on West Jessie Street, west of Interstate 5. • A new gravity interceptor would be installed along the east boundary of the Interstate 5 interchange, across West Lake Street to the existing sewer alignment that traverses around the north and south sides of the Tree house Inn. It would be necessary to use a trenchless installation under West Lake Street and Interstate 5. Replace sanitary sewer in (open cut) (east) Bore & jack sanitary sewer (north) Replace sanitary sewer (open cut) (east) Bore & jack sanitary sewer (north) Sanitary sewer (open cut) (north) HDPE gravity sanitary sewer (north) inside sanitary sewer (east) Replace sanitary sewer in same easement (open cut) (east) • The trenchless installations could be HDD or Bore and Jack (Photo 5A). • New easements will be required for much of this new alignment, and there would be impacts to existing wetlands on the east side of the Interstate 5 interchange. • A Caltrans encroachment permit would be required for boring under Interstate 5. Alternative 5 • The portion of interceptor south of South Old Stage Road will be constructed similar to Alternative 1. Photo Alternative 5A Typical bore and jack process used on Mt. Shasta’s 2007 Interceptor Replacement Project
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