Notice of Intent (NOI) To Prepare a Draft Environmental Impact Report and Environmental Impact Statement (EIR/EIS) for the Guadalupe Creek Restoration Project, San Jose, CA

AGENCY:

Army Corps of Engineers, DOD.

ACTION:

Notice of intent.

SUMMARY:

The Santa Clara Valley Water District (District) is proposing to establish riparian vegetation and shaded riverine aquatic (SRA) cover vegetation and to improve aquatic habitat in the lower reaches of Guadalupe Creek between Almaden Expressway and Masson Dam. The Guadalupe Creek Restoration Project (GCRP) is intended to offset environmental impacts associated with future District projects.

The intent of the Draft EIR/EIS is to describe and evaluate potential effects of these actions on environmental resources in the project area. The integrated EIR/EIS will include sufficient information for compliance with both the California Environmental Quality Act (CEQA) and the National Environmental Policy Act (NEPA), as well as opportunities for public participation in the planning and decision-making process. The lead agencies are the District and the U.S. Army Corps of Engineers (Corps).

DATES:

A public scoping period will begin on September 8, 2000 and end on October 7, 2000. Please submit comments by October 9, 2000.

ADDRESSES:

Comments should be submitted to Al Gurevich, Project Manager, Santa Clara Valley Water District, 5750 Almaden Expressway, San Jose, CA 95118. Electronic mail: ­AlGurevi@scvwd.dst.ca.us.

FOR FURTHER INFORMATION CONTACT:

1. Al Gurevich, Project Manager, Santa Clara Valley Water District, (408) 265-2607, or electronic mail: AlGurevi@scvwd.dst.ca.us.

2. Mr. Brad Hubbard, (916) 557-7054, or electronic mail: bhubbard@spk.usace.army.mil.

SUPPLEMENTARY INFORMATION:

Background: The district is proposing to establish approximately 6 acres of riparian vegetation and approximately 13,000 linear feet of SRA cover vegetation in order to improve aquatic habitat in the lower reaches of Guadalupe Creek between Almaden Expressway and Masson Dam. The GCRP in intended to offset environmental impacts associated with future District projects. Approximately 5,915 linear feet of the SRA cover vegetation planted along Guadalupe Creek under the proposed action could serve as offsite mitigation for the Guadalupe River Project in downtown San Jose (Downtown Project), if the Downtown Project is implemented. However, the GCRP is independent of the Downtown Project and will be implemented even if the downtown Project is not realized. This EIR/EIS intends to incorporate the Guadalupe River Project General Re-Evaluation Report/Environmental Impact Report-Environmental Impact Statement (GRR/EIR-SEIS) by reference to reduce duplication and paperwork associated with the GCRP EIR/EIS.

Study Area Location: Guadalupe Creek is located in the southwestern portion of the City of San Jose in San Jose in Santa Clara County. The project site is bordered upstream by Masson Dam, downstream by Almaden Expressway, to the north by residential development and the Los Capitancillos percolation pond system, and to the south by Coleman Road.

Document Scope: The environmental document to support the GCRP was originally scoped as an Initial Study/environmental Assessment (IS/EA), prepared in compliance with NEPA and CEQA. Analyses performed during the development of the draft IS/EA determined that the project may have the potential to result in a significant adverse effect on the environment. Therefore, the lead agencies have decided to prepare an EIR/EIS for the GCRP. The purpose of the integrated EIR/EIS is to develop and assess alternative plans for the GCRP that will avoid adverse effects on environmental resources. The EIR/EIS will address new information pertaining to mercury contamination within the project site, as well as alternative plans for the GCRP, and the potential effects and benefits of the GCRP. Furthermore, the document will explain the decision(s) that must be made, and identify the decision-makers in this combined CEQA/NEPA analysis.

Development and Evaluation of Alternative Plans for Project Modifications: The following primary objectives were developed by the project team, using input from public and agency scoping meetings. These objectives were used to develop the proposed action and alternatives.

1. Meet the measurable mitigation objectives defined in the Mitigation and Monitoring Plan (MMP) for the Guadalupe River Project, downtown San Jose, California, including requirements for instream cover, overhead cover, water temperature, stream stability, and shade.

2. Create riparian habitat, including SRA cover vegetation, that could provide mitigation credit for future District projects.

3. Restore physical processes and ecological functions of Guadalupe Creek along the project reach.

4. Protect existing infrastructure in the project area.

5. Maintain existing flood conveyance capacity.

6. Minimize impacts on existing resources.

In addition to the primary objectives, the project also has secondary objectives that may be achieved as part of the project, if they directly or indirectly support the primary objectives. The GCRP's secondary objectives are:

1. To enhance and restore habitat for special-status fish and wildlife species, as consistent with other project objectives;

2. To improve recharge of groundwater aquifers;

3. To minimize long-term operations and maintenance requirements;

4. To minimize impacts on existing water management operations;

5. To strive to meet regional planning objectives as outlined in relevant regional planning documents; and

6. Not to preclude future recreation uses that are compatible with other project objectives.

Evaluation Criteria and Range of Alternatives: Development of the alternatives was initiated with the goal of considering all feasible measures to achieve the planning objectives. The preliminary alternatives include: (1) Reduce floodplain excavation, (2) raise the bed of the channel, (3) stabilize the channel, and (4) the no-action/no-project alternative. Additional alternatives may be developed as a result of public comments received during the 30-day scoping period and further consultation with federal, state, and local regulatory agencies. Any additional alternatives that are developed will be included for evaluation in the EIR/EIS.

Alternatives Considered:

Proposed Action: The project site has been divided into four reaches. The following paragraphs describe proposed activities within each of the four reaches. In Reach 1, existing bank and terrace surfaces, including instream gravel bars, could be planted. Minimal physical modifications could be made to the channel and floodplain. Portions of the channel could be shifted to historic channel alignments creating surfaces for planting along Coleman Road. Instream structures (boulders and woody material) could be installed. Biotechnical structures could also be added along the north bank of the creek to increase channel complexity, narrow the low-flow channel, and increase hydraulic diversity while maintaining the low sinuosity of the existing channel.

In Reach 2, the existing planform of the creek could generally be maintained. Minor modifications could be made to lower floodplains in most areas, except downstream from the Meridian Avenue Bridge, where more extensive excavation could occur. Instream structures and bank stabilization structures could also be installed in this reach.

In Reach 3, project features could focus on modifying the existing channel and floodplain to reduce entrenchment, providing planting surfaces for riparian vegetation, and increasing hydraulic diversity in the channel. Instream structures could be added to stabilize the bed and banks, and woody material could be placed on bar surfaces to stabilize the bars and provide additional planting sites.

Because of the vegetation and habitat that already exist in the downstream segment of Reach 4, minimal modifications could be made to the channel in this area. However, downstream from Percolation Pond 1, approximately 350 feet of the existing maintenance road could be shifted to the north to create a wider bench adjacent to the channel. This could increase flood conveyance capacity and protect the road. In the upstream segment of Reach 4 the floodplain could be expanded.

Soil and sediment spoils excavated during project construction could be temporarily stockpiled onsite and analyzed to ensure that potentially contaminated materials (e.g., soils containing elevated mercury concentrations) are handled, transported, and disposed of in accordance with applicable state regulations. Spoils with mercury levels below state hazardous materials thresholds may be reused as fill onsite; guidelines regarding reuse of spoils will be developed in collaboration with state and federal regulatory and resource agencies.

Alternative 1. Reduced Floodplain Excavation: This alternative focuses on modifying the channel and adjacent floodplain surfaces to create SRA cover vegetation and instream cover. The extent of floodplain excavation (i.e., the limit of grading) on the project site would be reduced from the proposed action. Physical modifications would include altering channel and floodplain surfaces (e.g., channel relocation, floodplain development, and bank stabilization). Existing and created channel banks and floodplain surfaces would be planted and instream structures would be installed.

The intent of reducing the extent of excavation from that defined in the proposed action is to address the uncertainty associated with the amount of mercury-contaminated soil and sediment on the project site and the degree of mercury contamination. In addition, reducing the amount of excavation would reduce the extent of mercury-contaminated spoils hauled offsite. Excavation of channel banks and floodplains would still occur to create conditions conducive to plant establishment.

Alternative 2. Raising the Bed of the Channel: This alternative focuses on modifying channel and floodplain surfaces to create SRA cover vegetation and instream cover. Like Alternative 1, this alternative would include relocating portions of the channel, creating floodplain surfaces, stabilizing eroding banks, and installing instream structures. An additional element of Alternative 2 includes raising the bed of the channel to reverse the channel incision that has apparently occurred since the late 1800s. To raise the bed of the channel, existing riparian vegetation, SRA cover vegetation, and instream cover would need to be removed in some areas of Reach 4. This alternative would likely require additional excavation on floodplain surfaces to maintain flood capacity and would likely increase the frequency of flooding on existing lands adjacent to the channel, including the Los Capitancillos site.

The intent of raising the bed of the channel is to reduce the extent of excavation of mercury-contaminated soils, reduce the amount of mercury-contaminated spoils hauled offsite, and reduce the tendency for bank erosion (and consequently reduce the transport of mercury-laden sediments downstream). In addition, this alternative is intended to restore the existing bed elevation to historical conditions.

Alternative 3. Channel Stabilization: This alternative emphasizes stabilizing the channel to support SRA cover vegetation and create instream cover. Elements of this alternative include installing bed and bank biotechnical structures with small amounts of rip-rap. These elements would maintain and control channel form, control bank erosion and bed incision, provide SRA cover planting sites, and create instream cover. Channel modifications would control hydraulic conditions by limiting pool depth, areas of slow-moving water, and channel width. The extent of channel realignments on the project site would be reduced in this alternative relative to those described in Alternatives 1 and 2 and the Proposed Action. The intent of stabilizing the channel is to reduce the tendency for bank and bed erosion and thereby reduce the transport of mercury-laden sediments downstream.

Alternative 4. No-Action/No-Project Alternative: Under the no-action/no-project alternative, existing conditions and operations in the project reach would continue unchanged.

Possible Environmental Effects: Based on the available information collected and analyzed to date, significant effects will be avoided or minimized by the project design and by implementation of mitigation measures that will be proposed for the project. The resources for which potential adverse effects were identified include the following:

1. Air Quality. (1) Construction of the proposed action (or the alternatives) would generate increased air emissions for all criteria pollutants. In addition, sampling and analysis conducted for the proposed action have shown that soil and sediments along Guadalupe Creek contain elevated levels of mercury.

(2) Dust emissions could be generated by excavation and grading of soils along Guadalupe Creek, and by stockpiling and offhauling of excavated soil and sediments.

2. Biology: (1) Construction activities associated with the proposed action (or the alternatives) could result in the removal of approximately 1.1 acres of existing low-quality riparian scrub and forest habitat. (2) Although no state or federally listed wildlife species have been observed within the project area, potential habitat for California red-legged frog and southwestern pond turtle does exist onsite, and construction activities associated with the proposed action may adversely affect these species. Furthermore, construction activities associated with the proposed action may adversely affect all life stages of anadromous fish (steelhead and chinook salmon). (3) The proposed action was designed to avoid impacts on existing mature trees to the extent possible. However, mature trees may be removed or adversely affected by construction activities. (4) The project could result in the temporary loss of less than 1 acre of jurisdictional riverine wetland that is scattered in small patches along the edge of the low-flow channel, on benches, and on the edges of gravel bars.

3. Cultural Resources. All ground-disturbing project activities, such as excavation, planting, installation of instream structures, bank stabilization, channel modification, and floodplain alteration, have the potential to directly affect unknown cultural resources that may be covered by soil deposits or vegetation and thus could not be identified during previous field surveys or test excavations.

4. Hazardous Materials. (1) Construction activities associated with the proposed action (or the alternatives) may result in the exposure of soils with higher mercury concentrations than those found at the pre-excavation surface level. (2) Because historic and existing land use in the project area has been primarily agricultural and/or residential, it is unlikely that hazardous materials other than mercury-contaminated soils, sediments, and water could be found in the project area. However, during construction, subsurface hazards such as abandoned underground storage tanks and piping and contaminated material from undocumented dumping and landfilling may be encountered. (3) The project area is located approximately 0.25-0.3 miles from three schools: Pioneer High School, Vineland School, and Cinnabar School. (4) No hazardous emissions will be generated by the proposed action; however, excavation and the stockpiling, sampling, and disposal of excavated materials could require handling of mercury-contaminated soil and sediments.

5. Hydrology and Water Quality. (1) Site preparation and construction activities, including excavation and grading, could result in substantial soil disturbance and could lead to temporary discharges of soil and sediment directly into stormwater runoff or the stream channel. Construction activities also have the potential to discharge hazardous substances into water, such as fuel, oils, greases, and other petroleum products that may be released from machinery. (2) Implementation of the proposed action will require that Guadalupe Creek be dewatered during construction. Groundwater levels in the project area are affected by streamflow because the stream is a key recharge point for the aquifer. (3) The proposed action could alter hydraulic conditions in the project reach of the Guadalupe Creek, changing patterns of erosion and sediment deposition. (4) The proposed action could increase the potential for the formation of methyl mercury in the project reach.

6. Socioeconomics. Recent health advisories have indicated that human consumption of fish caught in the Guadalupe River watershed may pose a hazard to human health.

7. Traffic. (1) The proposed action could generate approximately 10 commute trips by construction/restoration workers during both the a.m. and p.m. peak commute hours. Additionally, between 292 and 350 one-way truck trips per day could be required to haul excavated material to and from the site. As much as 10% or 29-35 of the heavy truck trips could occur during the a.m. and p.m. peak commute hours. Implementation of the proposed action could temporarily add between 312 and 370 total daily vehicle and truck trips to local and regional roadways. (2) Restoration site access points involving heavy trucks (Camden Avenue and Almaden Expressway) may create roadway operation safety hazards.

Proposed Scoping Process: 1. This NOI initiates a 30-day period during which the District and the Corps will take comments on the issues to be addressed in the Draft EIR/EIS and the environmental issues related to the proposed action.

2. Public comment is encouraged on the proposal to prepare the Draft EIR/EIS and on the scope of issues to be included. Please provide comments within 30 days of publication of this notice to Mr. Al Gurevich at the Santa Clara Valley Water District (see ADDRESS above).

3. The District and the Corps will continue to consult local, state, and federal agencies with regulatory or implementation responsibility for, or expertise with, the resources in the area of investigation. These include, but are not limited to, the California Department of Fish and Game, U.S. Fish and Wildlife Service, National Marine Fisheries Service, and San Francisco Bay Regional Water Quality Control Board.

Previous Scoping Meetings: The District held two public scoping meetings during the IS/EA process to introduce the public and interested organizations to the project and to gather feedback. The meetings were held on February 17 and April 11, 2000. Public comments received at these meetings were recorded in scoping reports by the District.

Availability: 1. The Draft EIR/EIS is expected to be available for a public review and comment period beginning in November 2000.

2. The Final EIR/EIS is expected to be available for public review beginning in January 2001.