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Resolution 2530 . . . \., 2 3 4 5 \., 21 22 23 24 25 26 \.., 27 28 RESOLUTION NO. 2530 A RESOLUTION OF THE BOARD OF DIRECTORS OF SOUTH TAHOE PUBLIC UTILITY DISTRICT APPROVING NEGATIVE DECLARATION FOR SOUTH TAHOE PUBLIC UTILITY DISTRICT FALLEN LEAF LAKE SEWER COLLECTION SYSTEM IMRPOVEMENTS ASSESSMENT DISTRICT 1990-1 BE IT RESOLVED by the Board of Directors of South Tahoe 6 Public Utili ty District: 7 1) The Board finds on the basis of its review and 8 consideration of the Environmental Assessments for the Fallen 9 Leaf Lake Sewer Collection System Improvements Project, the 10 Preliminary Design Reports, all Comments received and Responses 11 thereto and modifications incorporated into the Project after 12 consideration of said Assessments, Reports, Comments, and 13 Responses, that there is no substantial evidence that the Project 14 will have a significant effect on the environment. 15 2) Based upon said finding the Board approves the 16 negative declaration circulated, a copy of which attached hereto 17 and made a part hereof. 18 PASSED AND ADOPTED by the Board of Directors of South 19 Tahoe Public Utility District at a regular meeting on the 7th 20 day of June, 1990, by the following vote: AYES: Directors Mason, Sinclair, Walker, Pierini, Onysk ABSTAIN: None NOES: None ABSENT: None ~~ ROBERT MASON, CHAIRMAN OF BOARD SOUTH TAHOE PUBLIC UTILITY DISTRICT ATTEST:_~a ~~ PAT A. MAMATH, ERK OF BOARD SOUTH TAHOE PUBLIC UTILITY DISTRICT \.,. NEGATIVE DECLARATION (CEQA) FOR THE SOUTH TAHOE PUBLIC UTILITY DISTRICT F ALLEN LEAF LAKE SEWER COLLECTION SYSTEM IMPROVEMENT PROJECT The South Tahoe Public Utility District is the Lead Agency pursuant to CEQA and has prepared an Environmental Assessment and Negative Declaration of Environmental Impact for the project described as the Fallen Leaf Lake Sewer Collection System Project. The District has conducted an Environmental Assessment of the Projects' impacts and has determined that, with mitigation incorporated in the project, there are no significant impacts. Applicant: South Tahoe Public Utility District. Application: Fallen Leaf Lake Sewer Collection System Project Location: Southwest shore of Fallen Leaf Lake The Tahoe Regional Planning Agency is the Lead Agency pursuant to the TRP A Compact, Regional Plan, and Code of Ordinances. .... Description of the Proposed Project The project consists of the construction of improvements to the existing sewer collection system at Fallen Leaf Lake. (Figure 1-3) The existing sewage collection system has had numerous breakdowns and system failures which have resulted in sewage being discharged on the ground and in some cases reaching Fallen Leaf Lake. A recent study by John Carollo Engineers titled "Fallen Leaf Lake Sewer Collection System Facilities Study", Oct. 1989, has identified improvements which will improve the operating reliability of the system. "The Project" has been designed in two phases. Phase I construction is the Project. The Phase I improvements are specifically designed to resolve the concerns of the Lahontan Regional Water Quality Board and the SWRCB Lahontan Board Order #6-89-95. The Phase I improvements consist of improvements to the vacuum stations and export line on the south side of Fallen Leaf Lake. The current system has been plagued with problems since its installation and completion in 1983. The general problems with the current system are due to the interdependent nature of all of the components of the system. A failure in one component, e.g. a vacuum station, causes a "domino effect" which can cause all of the vacuum stations to fail. '-' The new system improvements will replace the components which have caused the majority of the problems. The project will replace the ejector pumps and combine some of the vacuum stations to provide a significant increase in reliability. These improvements will also create more 5/29/'KJ Fallen Leaf Lake Sewer Collection System Improvement Project 1 \-," FALLEN LEAF LAKE SEWER COLLECTION SYSTEM MODIFICATIONS \., tLl SEAL EXISTING AIR RELEASE VALVE VAULTS ON MAIN EXPORT UNE (TOTAL OF 11) ,-... FALLEN LEAF LAKE ~ (S) MODIFY INSTRUMENTATION AT EXISTING MAIN EXPORT STATION (3) REMOVE VACUUM STATIONS VVS-1 AND VVS-2 <ID ADD STORAGE TANKS TO EXISTING VACUUM STATION VVS-3 ~ ADD PUMPS TO EXISTING VAULTS @ INSTALL 40 FT. PIPING FROM PRESSURE UNE TO EXISTING MANHOLE. INSTALL FLOW METER PS-2 I cJ STANfORD - SIERryA ...... CAM f-N Not to Scale A ril23,1990 Source: John Carollo En 'neers STPUD Pallen. Leaf Se~er System THE PROJECT Im pro"Vemen. t FIGURE 1-3 :I-1:.ARL.AN"D B.A.RT:I-1:C>LC>1vf:EYV &c .ASSC>CI.A TES, I:I:'-JC. ~ independence among the system components so that when one component fails, the entire system will not fail. The Project improvements consist of replacing the existing ejector pumps ES-1, ES-2 and ES-3 with conventional duplex pumps, and sealing the ejector vaults to act as wet wells. The vacuum system will also be improved by consolidation of vacuum stations VVS-1 and WS-2 into WS-3. Emergency storage will be added to VVS-3, and air release valves will be added to the vacuum main which will be converted for use as a pressure force main. Improvements to the main export system will be made by sealing the existing ARV vaults. Emergency power will be provided for the pump stations on the south side of Fallen Leaf Lake. The emergency generator will be housed in a small structure adjacent to Stanford Camp. Flow meters will be installed to collect flow data from Stanford Sierra Camp, Stanford Hill, and Fallen Leaf Lake Campground. Installation of the project will entail the following: site excavation and trenching; installation of piping and new pumps, installation of an emergency storage tank, and provide for standby power/emergency generator for the converted pump stations. Total additional permanent coverage for the project is estimated to be 135 sq. ft.; the project construction activities will impact an estimated 3,300 sq. ft. The disturbed areas will be revegetated and restored according to an approved BMP plan. \. Replacement of the ejector pumps will require some disturbance of the surrounding soils or geology. Replacement of the existing ejectors with conventional duplex pumps at stations ES-1, ES-2 and ES-3 will be done within the existing ejector vaults, which will also be sealed to act as wet wells. The converted ejector vaults will be a totally sealed container located underground to provide a wet well for the new duplex pumps. Consolidation of vacuum stations WS-1 and VVS-2 into WS-3 will also be accomplished with little excavation. The existing 4" vacuum main will be converted to a low pressure force main requiring air release valves to be installed at periodic intervals in the existing vacuum main. An emergency storage tank will be added to vacuum station WS-3. Standby/emergency power will be provided to the pump stations on the south side of the Lake. The standby power system will consist of a package generator, two exterior propane tanks and an electrical panel which will be housed in a structure about 15'x 9' in size. No other additional land coverage is proposed as part of the Phase I improvements. Refer to Figure 1-4 for the generator location. The Fallen Leaf Lake collection system improvements proposed in the future may consist of the following modifications: · The pumps at stations ES-6, 7, and 8 may be replaced with conventional duplex pumps. Stations ES-8 and ES-9 may be consolidated into one station; this consolidation would require approximately 700 feet of trenching. Emergency storage would be added into stations ES-5, 6, 7 and 9. fI..; S/29/rxJ Fallen Leaf Lake Sewer Collection System Improvement Project 2 \" · Other modifications proposed as part of future improvements may consist of consolidation of vacuum stations VVS-7 into VVS-8; approximately 500 lineal feet of trenching will be required to consolidate these two pump stations. The existing discharge pumps may also be replaced, and emergency power installed. The total cost for these future improvements is estimated to be approximately $900,000. Project Mitigation The Environmental Assessment is intended to address in detail the Phase I improvements proposed, the Project. If a determination is made that additional improvements must be installed, a successive Environmental Assessment will be made. Many of the impacts and mitigations identified for the Project improvements will, however, be similar for the future improvements. Geologyl Seismicity Trenching and excavation for new sewer lines, conversion of pump stations and the installation of emergency generators shall meet all local, state and federal seismic safety standards. \. Soils The project sites shall comply with the coverage requirements of the TRP A. Where project facilities exceed the allowable TRP A coverages, site specific coverage off-sets shall be proposed in compliance with the Chapter 20 of the TRP A Code of Ordinances. Air Quality Compliance with state vehicle emission control standards shall be required for all propane equipment. Machinery will be maintained in the best working condition. Water Quality All construction shall be completed in compliance with the TRP A code of ordinances; the project shall incorporate Best Management Practices into the design of soil stabilization and the contractor shall be required to follow Best Management Practices during construction. The District shall prepare an operations and maintenance manual for the operations and emergency response program for the improved collection system. The District shall require strict adherence to the approved operations and maintenance manual. Flora, Fauna and Fisheries All construction and on-site improvements shall be conducted in compliance with the adopted Best Management Practices. '-' 5/29/r:KJ Fallen Leaf Lake Sewer Collection System Improvement Project 3 4., Findings \. ~ Noise Powered equipment and vehicles used during construction phases and for site maintenance will be equipped with adequate mufflers and/or enclosures at all times. Construction activities or equipment with noise levels in excess of 50 CNEL or threshold single event levels will be limited to the hours of 8 a.m. to 6:30 p.m. Construction activity may begin before 8:00 a.m. if approved by the TRPA in compliance with the TRPA Code of Ordinances. Work at night will be specifically authorized by the TRP A. Scenic Resources Site revegetation and landscaping shall include plant materials to screen the generator from view from adjacent residential areas. All landscaping and revegetation shall be installed according to the TRP A Best Management Practices. Cultural Resources In the event that any cultural or historic resources should be uncovered during construction, all work will be stopped and an evaluation of the resource shall be conducted by a qualified professional in compliance with state and TRP A regulations. It has been found that this project as described herein and in the Environmental Assessment for the Fallen Leaf Lake Sewer Collection System, April 23, 1990, will not have a significant effect on the environment and an Environmental Impact Report (EIR) is not required by the California Environmental Quality Act. The following findings support the Negative Declaration of environmental impact: 1. The environmental impacts associated with the proposed modifications are construction related short-term impacts which will occur within the existing project site. No significant irreversible impacts associated with the project have been identified. 2. The project will not significantly alter the risk of upset or exposure to a risk of failure during a seismic event. The project will be engineered to the latest applicable UBC seismic standards. 3. Implementation of the project will increase the operational reliability of the sewage collection system and will eliminate or reduce the potential for spills of sewage into Fallen Leaf Lake. 4. Construction impacts associated with the project will be limited to the immediate area around the existing pump and ejector vaults. Each site will be revegetated and landscaped in accord with an approved Best Management Practices Plan for revegetation and erosion control. 5. The noise generated from the project pumps and emergency generator will be less than significant with the implementation of 5/29/rxJ 4 Fallen Leaf Lake Sewer Collection System Improvement Project \. acoustic project mitigation measures. During the construction of the project, noise from construction activities will dominate the noise environment in the immediate area. Construction activities will be temporary and will occur between 8:00 am and 6:30 pm. 6. The project will result in no permanent increases in vehicular trips. During the project construction period an estimated increase of 10 to 20 vehicle trips will be generated. 7. The project components will be installed in the existing pump vaults below ground with the exception of the emergency generator housing. Any person may object to dispensing with an EIR for this project, or they may respond to ,the findings in this Negative Declaration. Information relating to the proposed project is on file in the following locations: South Tahoe Public Utility District Attention: Robert Baer P.O. Box 19487 South Lake Tahoe, California 95706-3487 \. Tahoe Regional Planning Agency P.O. Box 1038 Zephyr Cove, Nevada 89448-1038 City of South Lake Tahoe 1052 Tata Lane P.O. Box 1210 South Lake Tahoe, CA 95705 EI Dorado County Library 1000 Rufus Allen Blvd, South Lake Tahoe, CA 95705 Harland Bartholomew and Assoc, Inc. 3807 Pasadena Avenue, Suite 180 Sacramento, Calif. 95821 Any person wishing to examine or obtain a copy of this document, or seeking information as to the time and manner to comment or register their objection, may do so by inquiring at said offices during regular business hours. A copy of the Environmental Assessment is attached hereto. day of May, 1990. Manager/Engineer \. South Tahoe Public Utility District 1275 Meadow Crest Drive, South Lake Tahoe, Calif. 95705 5/29/00 Fallen Leaf Lake Sewer Collection System Improvement Project 5