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HomeMy WebLinkAboutItem 6.4 Neg Decl I580FallonCITY CLERK FILE # 800-30 AGENDA STATEMENT CZTY COUNCZL MEETZNG DATE: October 3, 2000 SUBJECT: Public Hearing: Negative Declaration for the Interstate 580/Fallon Road Freeway Interchange Improvements Project Report Prepared by.' Lee S. Thompson, Public Works Director ATTACHMENTS: 1 ) Resolution adopting Mitigated Negative Declaration 2) Notice of Public Review of a Mitigated Negative Declaration for the Interstate 580/Fallon Road Freeway Interchange Improvements Project 3) Proposed Negative Declaration 4) Written Comments on the Proposed Negative Declaration 5) Response to Department of the Army 6) List of Mitigation Measures and Monitoring Requirements 7) Location Map RECOMMENDATION: 1 ) Open Public Hearing 2) Receive Staff presentation 3) Receive public testimony 4) Close public hearing 5) Deliberate 6) Adopt Resolution adopting Mitigated Negative Declaration for the Interstate 580/Fallon Road Freeway Interchange Improvements Project 7) Direct Staff to work with developers and Caltrans on development of the necessary Funding and Cooperative Agreements for construction of the Project FINANCIAL STATEMENT: There is no financial impact associated with the adoption of the Mitigated Negative Declaration for the entire project. Approval of this environmental document is a necessary step in the process of completing the project improvements. Eastern Dublin developers are advancing monies to construct the improvements and also receiving credits toward their Eastern Dublin Traffic Impact Fees. G:\miscproj\I~580 Fallon Rd\agst pub hearing neg dec.doc DESCRIPTION: The City has contracted with CCS Consulting Engineers to provide preliminary studies, including this environmental document, and construction documents for the improvements of the Interstate 580/Fallon Road Interchange. This project would modify the existing spread diamond interchange configuration to a partial cloverleaf and increase the traffic capacity of the interchange ramps and the ramp intersections with Fallon Road and E1 Charro Road. The City' s consultant has now prepared the proposed Mitigated Negative Declaration for the project in compliance with the California Environmental Quality Act (CEQA) and Caltrans Environmental Guidelines. A Mitigated Negative Declaration has been prepared, and Staff has determined that there will not be a significant adverse effect on the environment with the implementation of the mitigation measures identified in the Negative Declaration. Measures to mitigate the project impacts and monitoring requirements are summarized in Attachment 6. The Draft Initial Study/Mitigated Negative Declaration was circulated to the public for thirty (30) days, as required by CEQA. The Notice of Public Review of the Mitigated Negative Declaration for the project (Attachment 2) was mailed to property owners directly impacted by the project, posted in City information kiosks, and published in the Tri-Valley Herald, with the 30-day public comment period officially concluded on September 20, 2000. One comment letter, from the U.S. Army Corps of Engineers (Corps), as well as letters from Alameda County and the Dublin San Ramon Services District (DSRSD), were received. The response to comments received from the Corps are summarized in Attachment 5. The letters from Alameda County and DSRSD did not require responses. Staff concludes that the comments received are adequately addressed in the environmental document. Staff recommends that the City Council conduct a public hearing, deliberate, and adopt the resolution adopting the Negative Declaration for the Interstate 580/Fallon Road Interchange Improvements Project. Staff further recommends that the City Council direct Staff to work with the developers and Caltrans on the development of the necessary Funding and Cooperative Agreements for the construction of the Interstate 580/Fallon Road Interchange Improvements Project. -2- RESOLUTION NO. -00 A RESOLUTION OF THE CITY COUNCIL OF THE CITY OF DUBLIN ADOPTION OF A MITIGATED NEGATIVE DECLARATION FOR THE INTERSTATE 580/FALLON ROAD INTERCHANGE IMPROVEMENT PROJECT WHEREAS, the City of Dublin has planned to modify and improve the freeway interchange at Interstate 580 and Fallon Road/E1 Charro Road; and WHEREAS, the Interstate 580/Fallon Road Interchange Improvements Project is included in the 2000-2005 City of Dublin Capital Improvement Program; and WHEREAS, the project has been reviewed under the California Environmental Quality Act and the City of Dublin Environmental Guidelines, and a Mitigated Negative Declaration has been prepared for the project and mitigation measures have been included; and WHEREAS, the City of Dublin has issued a Notice of Public Review of Mitigated Negative Declaration for Interstate 580/Fallon Road Interchange Improvements and Notice of Public Hearing regarding the project, and the City of Dublin has conducted the public hearing on October 3, 2000; and WHEREAS, the City of Dublin has considered the Mitigated Negative Declaration and comments received during the public review period. NOW, THEREFORE, BE IT RESOLVED that the City Council of the City of Dublin does hereby adopt the Mitigated Negative Declaration for the Interstate 580/Fallon Road Interchange Improvements Project. PASSED, APPROVED AND ADOPTED this 3rd day of October, 2000. AYES: NOES: ABSENT: ABSTAINING: Mayor ATTEST: City Clerk g.' lmiscprojlI~580 Fallon Rdlreso neg dec. doc CITY OF DUBLIN P.O. Box 2340, Dublin, California 94568 City Offices, ! 00 CMc Plaza;. Z~,J;;!ir~. C;i_;iiforni~ 9456~j:. NOTICE OF PUBLIC REVIEW OF MITIGATED NEGATIVE DECLARATION PROJECT TITLE: Interstate 580/Fallon Road Interchange Improvements Project CAPITAL IMPROVEMENT PROJECT #: 96430 PROJECT LOCATION: Interstate 580/Fallon Road-E1 Charro Road Interchange APPLICANT: Lee S. Thompson Public Works Director City of Dublin 100 Civic Plaza Dublin, CA 94568 PROPERTY OWNER: California Department of Transportation P.O Box 23660 Oakland, CA 94623 PROJECT DESCRIPTION: The proposed project consists of improvements to the existing interstate 580 (I-580)/Tallon Road interchange, located within the Cities of Dublin, Pleasanton and Livermore. The 1-580/Fallon Road interchange improvements would modify the existing spread diamond (Type L-2) interchange configuration to a partial cloverleaf (Type L-9) configuration while increasing the capacity of the interchange ramps and ramp termini intersections. The proposed interchange improvements include: 1) widening the existing Fallon Road/E1 Charro Road overcrossing to provide two-lanes in each direction; 2) widening the eastbound 1-580' off-ramp to provide a second left-turn lane at the ramp termini at the intersection of E1 Charro Road; 3) constructing the eastbound 1-580 No-lane (one mixed-flow lane with an HOV by-pass) loop on-ramp; 4) widening northbound Fallon Road north of the overcrossing to provide additional storage at the intersection with the westbound ramps; 5) widening the westbound 1-580 off-ramp to provide four lanes (two left and two right-turn lanes) at the ramp intersection with Fallon Road; 6) widening Fallon Road approaching the intersection with the westbound ramps; 7) widening the westbound 1-580 on-ramp; 8) installation of traffic signals at the ramp termini intersections; and 9) constructing an auxiliary lane along westbound 1-580 from the southbound to westbound on-ramp to 400 meters (1,312 feet) east of the 1-580/Tassajara Road interchange. Administration (925)833-6650 - City Counci! (925)833-6605 · Finance "a95~ 833-6 Code Enforcement (925) 833-6620 · Engineering (925) 833-6630 · Parks & C Economic Development (925)833-6650 · Police (925)E33-6670 - Pt The project would be constructed almost entirely within the existing 1-580 right-of-way. Additional right-of-way in the northwest quadrant would be dedicated by the property owner prior to construction of the project. The dedication of this additional right-of-way would not require the relocation of any businesses or residences. Project construction would be completed in stages. ENVIRONMENTAL BACKGROUND & PUBLIC REVIEW: The proposed project site is the existing Interstate 580 (I-580)/Fallon Road interchange, located within the Cities of Dublin, Pleasanton and Livermore. The project site is located within the Eastern Dublin Specific Plan area. The Eastern Dublin Specific Plan was adopted by the City of Dublin in 1994 and has a certified Program EIR (SCH #1991-103064). The purpose of the Specific Plan is to direct long-term land use, circulation, infrastructure and environmental protection for 1,336 hectares (3,302 acres) of land located in eastern Dublin and noah of 1-580. At full buildout, a range of residential, commercial, office, employment, and open space uses would be located in this area. In addition, there has been much recent development south of the interchange area, in the Cities of Pleasanton and Livermore. The purpose of the proposed interchange improvements would be to accommodate future traffic demand, including traffic generated by several recently approved developments north of the project site, as well as to accommodate existing and future development south of the interchange. The City of Dublin, as the Lead Agency, has prepared a focused Initial Study and Mitigated Negative Declaration for the above-referenced proposed project. The public review period for the Mitigated Negative Declaration and Initial Study will be from August 22, 2000 to September 22, 2000. The City will accept comments on the proposed project during the public review period. Copies of the Mitigated Negative Declaration and Initial Study are available for review at the City of Dublin City Hall, 100 Civic Plaza, Dublin, California. If you have any questions or comments, please contact the City of Dublin Department of Public Works at (925) 833-6630. Director of Public Works Dated: Published: August 16, 2000 August 22, 2000 PROPOSED NEGATIVE DECLARATION (Prepared pursuant to City of Dublin Environmental Guidelines, Section 1.7(c), 5.5) Description of Project: The proposed project consists of improvements to the existing Interstate 580 (I-580)/Fallon Road interchange, located within the Cities of Dublin, Pleasanton and Livermore. The 1-580/Fallon Road interchange improvements would modify the existing spread diamond (Type L-2) interchange configuration to a partial cloverleaf (Type L-9) configuration while increasing the capacity of the interchange ramps and ramp termini intersections. The proposed interchange improvements include: 1 ) widening the existing Fallon Road/El Charro Road overcrossing to provide two lanes in each direction; 2) widening the eastbound 1-580 off-ramp to provide a second left-turn lane at the ramp termini at the intersection of El Charro Road; 3) constructing the eastbound 1-580 two-lane (one mixed-flow lane with an HOV bypass) loop on-ramp; 4) widening northbound Fallon Road north of the overcrossing to provide additional storage at the intersection with the westbound ramps; 5) widening the westbound 1-580 off-ramp to provide four lanes (two left- and two right-turn lanes) at the ramp intersection with Fallon Road; 6)widening Fallon Road approaching the intersection with the westbound ramps; 7) widening the westbound 1-580 on-ramp; 8) installation of traffic signals at the ramp termini intersections; and 9) constructing an auxiliary lane along westbound 1-580 from the southbound to westbound on-ramp to 400 meters (1,312 feet) east of the 1-580/Tassajara Road interchange. Project Location: Interstate 580/Fallon-El Charro Road Interchange. Name of Proponents: City of Dublin, Public Works Department, 100 Civic Plaza, Dublin, CA 94568 I hereby find that the above project will not have a significant adverse effect on the environment. Attached is a copy of the Initial Study ("Environmental Information Form" and "Environmental Checklist") documenting the reasons to support the above finding. Mitigation Measures have been included in this project. Dated: 2000 Lee S. Thompson, Director of Public Works Attachments g:miscproj\l-580 fallon rd~neg dec ATTACHMENT REPLY TO ATTENTION OF: Regulatory Branch DEPARTMENT OF THE ARMY SAN FRANCISCO DISTRICT, CORPS OF ENGINEERS 333 MARKET STREET SAN FRANCISCO, CALIFORNIA 94105-2197 SUBJECT: File Number 255705 Mr. Lee Thompson City Dublin P.O. Box 2340 Pleasanton, California 94568 Dear Mr. Thompson: Your request for comments on the Draft Initial Study/Mitigated Negative Declaration for the Interstate 580 Fallon Road Interchange' Improvements Project was received on August 23, 2000. All proposed discharges of dredged or fill material into waters of the United States must be authorized by the Corps .of Engineers pursuant to Section 404 of the Clean Water Act (CWA) (33 U.S.C. 1344). Waters of the United States generally include tidal waters, lakes, ponds, rivers, streams (including intermittent streams), and wetlands. Your proposed work appears to be within our jurisdiction-and a permit may be required. Application for Corps authorization should be made to this' office using the application form in the enclosed pamphlet. To avoid delays it is essential that you enter the file number at the top of this letter into Item No. 1. The application must include plans showing the location, extent and character of the proposed activity, prepared in accordance with the requirements contained in this pamphlet. YOu should note, in planning your work, that upon receipt of a properly completed application and plans, it may be necessary to advertise the proposed work by issuing a public notice for a period of 30 days. If an individual permit is required, it will be necessary for you to demonstrate to the Corps that your proposed fill is necessary because there are no practicable alternatives, as outlined in the U.S. Environmental Protection Agency's Section 404(b)(1) Guidelines. A copy is enclosed to aid you in preparation of this alternative analysis. -2- If you have any questions, please call Victoria Alvafez of our Regulatory Branch at 415-977-8472. Please address correspondence to Regulatory Branch and refer to the file number at the head of this letter. Sincerely, ~'b")Calvin C. Fong Chief, Regulatory Branch Enclosures DUBLIN SAN RAMON SERVICES DISTRICT 7051 Dublin Boulevard Dublin, California 94568 FAX: 925 829 1180 925 828 0515 September 22, 2000 Lee S. Thompson, Director of Public Works City of Dublin 100 Civic Plaza Dublin, CA 94568 2000 Subject: Mitigated Negative Declaration for Interstate 580/Fallon Road Interchange Improvements Project, City of Dublin Dear Mr. Thompson: Thank you for providing Dublin San Ramon Services District the opportunity to review and comment on the Mitigated Negative Declaration for the 580/Fallon Road Interchange project. Our agency has identified no impacts or necessary mitigations beyond those identified in the Focused Initial Study and Mitigated Negative Declaration. Sincerely, Senior Planner BW:jg I\S N DE t It e D 1 n Services DIstrict is a Public Enuty ALAMEDA COUNTY COMMUNITY DEVELOPMENT AGENCY Adolph Martinelli Agency Director 224 West Winton Avenue Room 110 Hayward California 94544-1215 phone 510. 670.5333 fax 510. 670.6374 www. co.alameda.ca.us/cda September 22, 2000 PIJE LIC WORKS Lee S. Thompson. Public Works Director City of Dublin 100 Civic Plaza Dublin, CA 94568 SUBJECT: Interstate 580/Fa!ion Road Interchange Improvements Project Dear Mr. Thompson: Thapdc you for the opportunity to review the Mitigated Negative Declaration on the above project. Staff has reviewed the document, and has the following comments. As you are well aware, there has been a significant level of new residential and commercial development approved in this portion of Alameda County. This project will accommodate the expected growth in traffic, and increase the ability of current and future residents and commuters to access this area with minimal delays. In particular, it will create improvements that will be important to the Staples Ranch development, which is located in the southwest quadrant of the study area. Therefore, the County is in full support of this project. Please do not hesitate to contact Cindy Horvath of my staff@ (510) 670-6511 if you have any questions or require additional information. Sincerely, Kd?~lli, Director Alameda County Community Developmere Agency CITY OF DUBLIN P.O. Box 2340, Dublin, California 94568 : ® City Offices, 100 Civic Plaza, Dublin, California 94568 September 27, ·2000 Calvin C. Fong Chief, Regulatory Branch U.S. Army Corps of Engineers 333 Market Street San Francisco CA 94105-2197 SUBJECT: Response to Letter Dated September 1, 2000, Commenting on the Draft Initial Study/Mitigated Negati~/e Declaration' for 1-580/Fallon Road Interchange Project Dear Sir: Three' comment letters relating to the Draft Initial Study/Mitigated Negative Declaration (IS/MND) for the 1-580/Fallon Road Interchange Improvements project were received from public agencies. This response is to provide additional clarification to the issues raised in the U.S. Army Corps of Engineers letter, dated September 1, 2000, regarding the Draft IS/MND. The letters from Alameda County and the Dublin San Ramon Services District require no responses. The letter from the U.S. Army Corps of Engineers (Corps) states that the proposed project work appears to be within the Corps' jurisdiction, and that a permit from the Corps may be required. · As described in the IS/M ND, a total of approximately 0.0174 hectares (0.043 acres) of potential jurisdictional wetlands habitat is present on-site, north of the interchange. In addition, there are several man-made drainage ditches present in the project site area. However, these drainage ditches did not meet the criteria for Corps jurisdiction, and a letter from the Corps (File Number 24722S), dated February 1, 2000, was received by the City Of Dublin, which disclaimed jurisdiction over these non-tidal drainage ditches in the interchange area. Mitigation measures were identified on pages 36 and 37 of the Draft IS/MND to reduce impacts' to jurisdictional wetland habitat to a less than significant level. As stated on page 36 of the Draft IS/MND, prior to construction, the project shall apply for a Section 404 permit from the Corps and for Section 401 certification from the Regional Water Quality Control Board. The project proponent would comply with the conditions of these regularcry documents. It is the City's opinion, as concluded in the Draft IS/MND, that with the implementation of mitigation measures identified in the Draft IS/MND, potential impacts to seasonal aquatic habitat and jurisdictional wetlands would be reduced to a less than significant level. Sincerely, ' ~ ' · ' .......Zee s. Thompso~"~X'/" Public Works Director g:kniscproj\l~580 Fallon Rd~Army response Itr.doc Administration (925)833-6650" City Council (925)833-6605 - Finance (925)833 Code Enforcement (925) 833-6620 , Engineering (925) 833-6630 · Parks Economic Development (925)833-6650 · Police (925)833-6670 · MITIGATION MEASURES AND MONITORING REQUIREMENTS Impact ] Mitigation Construction of the proposed interchange improvements would result in short-term air quality impacts due to the generation of dust by construction equipment and vehicles. Less Than Significant Impact Air Quality In order to minimize temporary construction-related dust impacts, the project would conform to the Best Management Practices (BMPs) and procedures identified in Caltrans specifications. The specific measures implemented could include the following: 1) Water all active construction areas daily; 2) Sweep all paved access roads, parking areas and staging areas at construction sites as needed (to be determined by resident engineer); 3) Sweep streets if visible soil material is carried onto adjacent public streets as needed (to be determined by resident engineer); 4) Limit traffic speeds on unpaved roads to 15 mph; 5) Install sandbags or other erosion control measures to prevent silt runoff to public roadways; 6) Replant vegetation in disturbed areas as quickly as possible; 7) Install windbreaks, or plant vegetative wind breaks at windward side(s) of construction areas; and 8) Limit the area subject to excavation, grading and other construction activity at any one time. 'Less Than Significant Impact Biological Resources A small population (20 individuals) of Congdon's tarplant was found on-site, within the proposed improvement and 15.2-meter (50-foot) construction areas located immediately west of Fallon Road. The loss of this relatively small population, when compared to the existence of two, significantly larger populations (i.e., an estimated 24,000 in Livermore and at least 10,000 on Camp Parks, [less than 1.6 kilometers/one mile west]) in the vicinity of the project site, is not considered to be a significant impact. Less Than Significant Impact Prior to site disturbance, the seeds from this annual species would be collected and sown among populations that exist in the region, such as the Springtown Alkali Sink Preserve in Livermore. Less Than Significant Impact 1-580/Fallon Road Interchange Project September, 2000 MITIGATION MEASURES AND MONITORING REQUIREMENTS Impact Mitigation Biological Resources (cont.) Breeding habitat does not exist on-site or downstream of the project site for Califomia red-legged frogs. However, individual red- legged frogs (and in particular, dispersing juveniles) could potentially occur in the seasonal aquatic habitat adjacent to the interchange during the rainy season. The loss of individual frogs or the degradation of the water quality of this habitat area during construction activities could potentially impact red-legged frogs that may occur in this habitat. Significant Impact The following mitigation measures, which are included as part of the project, would reduce potential impacts to California red-legged frogs to a less than significant level. 4.1 Prior to construction activities, a preconstruction survey would be conducted by a qualified biologist (defined as a person permitted by the U.S. Fish and Wildlife Service to capture and move red- legged frogs) in the immediate area of construction both in the seasonal aquatic habitat and in the vicinity where equipment and construction activities would be located. If individual red-legged frogs are found during the preconstruction survey, the biologist would remove them from the site and relocate them to suitable habitat in t_he vicinity. 4.2 A meeting would take place before the commencement of construction in the wetland area so that the biologist can explain to construction workers how best to avoid the accidental take of red- legged frogs to minimize potential impacts to these species. 4.3 To minimize potential impacts to red-legged frogs on-site and downstream, construction within and adjacent to the wetland would be restricted to the dry season, and it should be confirmed that the pond is actually dry prior to construction activity commencement. Best Management Practices (BMP) would be implemented. Less Than Significant Impact with Mitigation Incorporated 1-580/Fallon Road Interchange Project 2 September, 2000 MITIGATION MEASURES AND MONITORING REQUIREMENTS Impact Mitigation If Burrowing Owls are present on-site at the time of construction, construction disturbance during the breeding season could result in the incidental loss of fertile eggs or nestlings, or otherwise lead to nest abandonment. Although the site is not presently occupied by Burrowing Owls, Owls could move onto the site's suitable habitat prior to completion of all phases of development. Significant Impact Biological Resources (cont.) Implementation of the following mitigation measures, which are included as part of the project, would mitigate potential impacts to Burrowing Owls to a less than significant level. The following mitigation measures were identified as mitigation measures 3.7/20.0 and 3.7/27.0 in the Eastem Dublin General Plan Amendment EIR. 4.4 In conformance with federal and state regulations protecting raptors against direct "take," a qualified ornithologist would conduct pre-construction surveys for Burrowing Owls prior to any soil- altering activity, construction, or development on the site. The preconstruction surveys would be conducted per CDFG guidelines (no more than 30 days prior to the start of site grading), regardless of the time of year in which grading occurs. If no Burrowing Owls are found, then no further mitigation would be warranted. If, as determined by the omithologist in consultation with the CDFG, Owls are located on or immediately adjacent to the site, a construction-free buffer zone of at least 300 feet around the active burrow would be established. No activities, including grading or other construction work, would proceed until the buffer zone is established, or a CDFG approved relocation of the birds has been performed (such relocations can occur only during the non- reproductive season (September through January). 4.5 If preconstruction surveys confirm that Burrowing Owls occupy the site, then avoidance of impacts to the habitat utilized by these Owls would be considered the preferred mitigation method. Avoidance would allow the use of areas currently occupied by Burrowing Owls to continue uninterrupted. 1-580/Fallon Road Interchange Project 3 September, 2000 _'>, MITIGATION MEASURES AND MONITORING REQUIREMENTS Impact Mitigation Biological Resources (cont.) 4.6 If preconstruction surveys determine that Burrowing Owls occupy the site, and avoiding development of occupied areas is not feasible, then habitat compensation on off-site mitigation lands would be implemented. Off-site mitigation typically entails evicting the affected Owls from the project site and setting aside and managing specific areas for Burrowing Owls. Burrowing Owls would not be evicted from the site during the breeding season. A single, large, contiguous mitigation site is preferable to several smaller, separated sites. The mitigation site would preferably support Owl nesting and be contiguous with or at least proximal to other lands supporting Burrowing Owls. Sites with a long history of Burrowing Owls use, or that have at least been in a suitable condition for occupancy are preferred. Grazing is compatible with Burrowing Owl occupancy. If Owls are found on-site, then the project shall conform with the CDFG guidelines, which require that off-site mitigation lands be set-aside at a ratio of 2.6 hectares (6.5 acres)/pair or individual Owl (if only an individual is observed). The City of Dublin could identify and set aside the mitigation land prior to site grading if Owls are located on-site. Alternatively, the project sponsors could place a security deposit or other financial assurance (e.g., performance bond, letter of credit, etc.) into a CDFG Burrowing Owl mitigation fund prior to grading. Funds would be expended towards the acquisition and long-term management of a mitigation site. Less Than Significant Impact with Mitigation Incorporated 1-580/Fallon Road Interchange Project September, 2000 MITIGATION MEASURES AND MONITORING REQUIREMENTS Impact Mitigation Biological Resources (cont.) A total of approximately 0.0174 hectares (0.043 acres) of seasonal aquatic habitat is present on-site. The intersection improvements at Fallon Road and the westbound 1-580 on-ramp and associated grading would impact (fill) approximately 0.017 hectares (0.042 acres) of seasonal aquatic habitat west of Fallon Road. This includes approximately 0.01 hectares (0.025 acres) of area that would be covered with pavement (permanent impact) and 0.007 hectares (0.017 acres) within the 15.2-meter (50-foot) construction easement (temporary impact). In addition, approximately 23.2 square meters (250 square feet) of seasonal aquatic habitat that occurs within the right-of-way east of Fallon Road would also be impacted. Significant Impact The project applicant would incorporate either measures 4.7 and 4.8 or measure 4.9 into the project. 4.7 As mitigation for the permanent loss of wetlands, impacted seasonal aquatic habitat would be replaced, either in conjunction with mitigation for proposed wetland impacts associated with the Dublin Ranch development or at an approved local mitigation bank or adjacent property. Impacted wetlands would be mitigated at a minimum ratio of 2:1 (replaced:impacted). To mitigate impacts to wetlands, 0.0348 hectares (0.086 acres) of wetlands would be created. A detailed wetland restoration' plan would be prepared in consultation with a qualified restoration biologist. Such a plan would provide the following: 1) replacement of lost wetland habitat; 2) location of on-site restoration opportunities, complete with an analysis of the technical approach to create high quality wetlands; and 3) prior to construction, the project applicant shall apply for a Section 404 permit from the Corps and Section 401 certification from the Regional Water Quality Control Board. The project proponent would comply with the conditions of these regulatory documents. 4.8 The project proponent would also comply with the following additional recommendations: 1) A detailed plan would be created for wetland construction that includes excavation elevations, location of hydrologic connections and soil amendments, if necessary; 2) Planting, maintenance and monitoring plans would be prepared in consultation with a qualified habitat restoration specialist; 3) Constructed wetlands would be monitored for a period of five (5) years and the site should achieve 80 percent cover by native marsh plant species by Year 5o Specific performance criteria would be determined and monitored for site success. 1-580/Fallon Road Interchange Project September, 2000 MITIGATION MEASURES AND MONITORING REQUIREMENTS Impact I Mitigation Biological Resources (cont.) 4.9 Alternatively to measures 4.7 and 4.8, the replacement of lost habitat functions and values of the seasonal aquatic habitat can be achieved through some form of in-lieu fee mitigation. The appropriate fee would be set in consultation with state and federal resource agencies. Less Than Significant Impact with Mitigation Incorporated Cultural Resources No recorded archaeological sites or known Native American settlements have been identified within or adjacent to the I- 580/Fallon Road interchange area. The project is not anticipated to impact archaeological or historic resources. Less Than Significant Impact The standard measures described below are included in the project to minimize the potential for impacts to archaeological or historic resources: Areas to be disturbed two or more feet below the surface will be identified in the final project design plans, Construction work in areas where foundations will be constructed two or more feet below the ground surface will be monitored by a qualified on-site archaeologist. In the unlikely event that buried archaeological resources are · discovered during project construction activities, work shall be halted until a qualified archaeologist has been retained and consulted regarding the significance of any such discovery. Uncovered resources will be treated in accordance with Section 106 of the National Historic Preservation Act, State law, and the protocol set forth in the CEQA Guidelines, In the event that the archaeologist determines that future excavation would endanger a significant cultural resource at this location, it would be the responsibility of the archaeologist to present the City with a proposal for the mitigation of impacts to the resource before work is allowed to continue. Less Than Significant Impact 1-580/Fallon Road Interchange Project September, 2000 MITIGATION MEASURES AND MONITORING REQUIREMENTS Impact ~ Mitigation Hazards and Hazardous Materials Because the 1-580/Fallon Road interchange area has supported vehicular activity since the 1950's, it is highly likely that the surface soils along these areas contain aerially-deposited lead from exhaust of cars buming leaded gasoline. The release of lead during construction of the proposed interchange improvements could impact nearby residences and land uses. Significant Impact In order to minimize potential impacts from the likely presence of aerially-deposited lead, the following mitigation measures are included as part of the project: Surface soil samples would be collected and analyzed prior to project construction to determine the applicability of reuse under the Department of Toxic Substance Control Lead Variance. Soils contaminated with elevated levels of aerially-deposited lead would be disposed in accordance with the requirements of the Department of Toxic Substance Control Lead Variance. These soils would either be removed from the site prior to or during construction or buried within the fill soils during project construction. The project will also be required to comply with Section 25157.8 of the Califomia Health and Safety Code. If soils containing in excess of 350 parts per million of aerially-deposited lead are encountered during construction, these soils will be disposed of in a Class I hazardous waste disposal facility, in accordance with Section 25157.8 of the California Health and Safety Code. Less Than Significant Impact with Mitigation Incorporated 1-580/Fallon Road Interchange Project 7 September, 2000 MITIGATION MEASURES AND MONITORING REQUIREMENTS Impact Mitigation Hydrology and Water Quality The proposed interchange improvements would result in a slight increase in runoff due to the increased pavement areas. Construction of the proposed interchange improvements would require grading and overcovering of the soil in order to construct additional lanes and on-ramps. Erosion during project construction could increase pollution and sedimentation impacts to the drainages on- and off-site. Less Than Significant Impact The following mitigation measures, which are included as part of the project, would reduce potential short-term water quality impacts to a less than significant level. 8.1 The project would be required to comply with the Caltrans National Pollutant Discharge Elimination System (NPDES) Permit and General Construction Activity Storm Water Permit requirements. Prior to construction grading, the applicant would prepare and implement a Storm Water Pollution Prevention Plan (SWPPP) that identifies measures that would be included in the project to minimize and control construction and post-construction erosion and runoff. Measures included in the SWPPP would preclude non-stormwater discharges to the stormwater system and require monitoring of discharges to the stormwater system. 8.2 The project would implement Best Management Practices (BMPs) of Caltrans to prevent stormwater pollution and minimize potential sedimentation during construction. These BMPs could include the following specific measures: 1) using silt fencing to retain sediment on the project site; 2) providing temporary cover of all disturbed surfaces to help control erosion during construction; and 3) providing permanent cover to stabilize the disturbed surfaces after construction has been completed. In the event that construction over the drainage channels causes the deposition of soil-laden drainage into the channels, or otherwise interferes with channel operation, the project would include post- construction cleanup within these channels. Less Than Significant Impact 1-580/Fallon Road Interchange Project 8 September, 2000 DUBL/~"----- BLVD. Interchange Improvements Area LOCATION MAP