95959 | 01/11/2019 | Ad id: 7-0000364613

NOTICE OF AVAILABILITY VAN NORDEN DAM SPILLWAY MODIFICATION PROJECT DRAFT ENVIRONMENTAL IMPACT REPORT STATE CLEARINGHOUSE NO. 2018012053 JANUARY 11, 2019 Notice is hereby given that a 45-day review period has begun to provide interested individuals an opportunity to review and respond to the adequacy of the Draft Environmental Impact Report (DEIR) prepared for that project known as the Van Norden Dam Spillway Modification Project. LEAD AGENCY: Nevada County PROJECT TITLE: Van Norden Dam Spillway Modification Project PROJECT LOCATION: The proposed project is located in the west end of Summit Valley in Soda Springs, Nevada County. The historic Lake Van Norden, which was created by and is hydraulically dependent on the Van Norden Dam spans Nevada County and Placer County. The dam site is accessed via Soda Springs Road. The Union Pacific railroad tracks traverse east to west approximately 660 feet north of the dam. Donner Pass Road and Interstate 80 roughly parallel the railroad tracks 1,350 and 2,000 feet north of the dam, respectively. PROJECT DESCRIPTION: The Van Norden Dam is located on property owned and managed by the Truckee Donner Land Trust (TDLT). TDLT is proposing modifications to the dam spillway that would lower the spillway to eliminate the risk from a dam failure and remove the ability to impound water for which the TDLT has no rights. The existing notch of the spillway would be lowered by 4.5 feet. The new spillway would be 48 feet wide and 95.4 feet long with concrete aprons on the upstream and downstream ends of the spillway. The new spillway would include a small incised channel 0.5-foot-deep and 3 feet wide to allow water passage during low flow conditions in the summer and fall months. A 5-foot-deep by 1.5-foot-wide concrete wall would be placed below the modified spillway on the upstream portion of the spillway to prevent water seepage. The existing scour basin on the downstream side of the dam would be improved with new riprap for erosion protection. The existing 22-inch outlet pipeline would be removed. Anticipated construction equipment to be used would include concrete saws, cranes, excavators, concrete supply trucks, haul trucks, trenchers, backhoes, and grading trucks. Construction equipment would be staged at previously disturbed and compacted locations on site based on the phase of construction activity. Construction fencing and water quality control features would be installed to avoid impacts outside of the construction area. The construction area would be marked (as appropriate) with orange construction fencing or similar demarcation. The construction ingress and egress points would have a gravel apron to prevent off-tracking. In addition, the excavated materials would be stabilized on-site within the old historic spillway until soils are utilized for other mitigation projects. Construction activities would also include vegetation removal within the construction zone that would be stored in the construction zone and eventually hauled off-site. Materials that would be imported or exported from the site would include the following: concrete and shotcrete removed from the dam (export 98 cubic yards), soil excavated from the site (export 995 cubic yards), concrete for the concrete aprons (import 223 cubic yards), and riprap (import 816 tons). Construction would take place sometime between August and October of 2019. Should dewatering be required, it would likely occur in the excavation trench associated with the new concrete wall for seepage protection. Dewatering would take place on the downstream side of the existing dam, near the parking lot and the toe of the slope. Dewatering fluids (water) would be treated as necessary so there is no additional sediment loading to the South Yuba River. Water would go through water quality control features to protect water quality and would be discharged back to the river through the existing channel downstream of the scour basin at a rate that would not cause erosion. SIGNIFICANT ENVIRONMENTAL EFFECTS: The County has prepared a DEIR to address the specific environmental effects of implementing the Van Norden Dam Spillway Modification Project. The DEIR consists of an analysis of the following environmental issue areas that may be impacted by the project: Aesthetics Land Use and Planning Agriculture and Forestry Resources Mineral Resources Air Quality Noise Biological Resources Population and Housing Cultural and Tribal Cultural Resources Public Services Energy Recreation Geology and Soils Transportation and Traffic Greenhouse Gas Emissions Utilities and Service Systems Hazards and Hazardous Materials Cumulative Impacts Hydrology and Water Quality Growth Inducing Impacts PUBLIC REVIEW PERIOD/STATUS: A 45-day public review period will be provided to receive written comments on the adequacy of the Draft EIR. The comment period will start on January 11, 2019, and end on February 25, 2019 at 5:00 pm. Written comments should be sent to the following address: Coleen Shade, Senior Planner, Nevada County 950 Maidu Avenue Nevada City, CA 95959-8617 Phone: 530-470-2526 Email: Email Me PUBLIC MEETING: A public meeting to receive comments on the adequacy of the Draft EIR will be held on February 14, 2019, at 1:30 p.m. at the Town of Truckee's Council Chambers, 10183 Truckee Airport Road 950, Truckee CA 96161 before the Nevada County Planning Commission. AVAILABILITY OF THE DRAFT EIR: Copies of the Draft EIR are available for review at the following locations: Nevada County Planning Department, 950 Maidu Avenue, Nevada City, CA Nevada County Truckee Library, 10031 Levon Avenue, Truckee CA The Van Norden Dam Spillway Modification Project DEIR may also be reviewed on the County's website www., under the current planning projects link. Publication: January 11, 2019 Ad #0000364613