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3.4.13 Environmental Consequences: No Project Alternative The No Project Alternative will not involve a change in the Baseline Condition. Maintenance of the existing condition for fish will involve continued operation of three major unscreened water diversions from early spring through late summer to early fall. The consequences of this operation will be continued entrainment of eggs, larvae, juveniles, and some adult fish of all species. This is an inherently adverse effect, as entrained fish are stranded in irrigation and drainage facilities where they experience prolonged exposure to poor water temperature and water quality and high rates of predation. In addition, the No Project Alternative will not convert about 100 feet of riprapped levee to a vertical fish screen and thus juvenile fish of all species will be subject to predation by non-native piscavores that prefer riprapped habitat for ambush-type predation. At the same time, the No Project Alternative will not create an exposed area adjacent to the proposed fish screen where small fish may be more visible to mid-channel predators such as resident trout. There will be no noise and sediment effects. There will be no potential for disturbance of nesting raptors during construction. The No Project Alternative will also not temporarily or permanently convert ruderal habitats along the Sacramento River levees and along the canal alignments. There will be no potential reduction of movement corridors between riparian zones along the river. 3.5 Air Quality 3.5.1 Affected Environment Air Quality in the project area is influenced by development in the south and west of the Sacramento Basin and by pollutants from these areas blown into the project area by the prevailing southwest winds, particularly during the summer. In addition, agricultural operations may, at times, generate dust. The pollutants of greatest concern in the project area are ozone and inhalable particulate matter (PM10). Ozone precursors, reactive organic gases (ROB) and oxides of nitrogen (NOx) react in the atmosphere in the presence of sunlight to form ozone. Because photochemical reaction rates depend on the intensity of ultraviolet light and air temperature, ozone is primarily a summer air pollution problem. PM10 emissions are generated by a variety of sources, including agricultural activities, construction, and traffic. Carbon monoxide concentrations are generally elevated near heavily traveled intersections. Because the positive barrier fish screen would be located in a rural area, carbon monoxide is not a concern. The EPA has promulgated a rule requiring that all Federal actions in Federally designated non-attainment areas comply with applicable state implementation plans (SIPs) (40 Code of Federal Regulations [CFR] Parts 6, 51, and 93). Federally funded projects in Federal attainment areas are potentially subject to the conformity rule. Northern Yolo and southern Colusa County, where the proposed project site is located, is a Federal attainment area for carbon monoxide. Thresholds are 100 tons/year for offsets and Best Available Control Technology (BACT) threshold of 500 ppb. Northern Yolo and southern Colusa County is a non-attainment area for PM10 and ozone. Implementation of the proposed project would result in the following impacts to air quality:
3.5.3 Environmental Consequences of No Action Implementation of the No-Action Alternative would avoid the temporary construction-related air quality impacts of the proposed project. 3.6 Land Use 3.6.1 Affected Environment Land use in the vicinity of the proposed action is agricultural, with 4 scattered residences/farm operation facilities. Crops include row crops, orchards, and rice (primarily south and west of Tyndall Mound. On the west side of the Sacramento River, there are no towns or residential communities within 5 miles. 3.6.2 Environmental Consequences of Proposed Action There is no mechanism by which the project would change general land uses. The project would not change economic or social conditions; it does not increase or decrease irrigation deliveries, not would it affect the timing of deliveries. Conditions for agriculture would not, thus, be affected and no change in agricultural uses would result from the project. The project would not affect growth or development. The project would not increase population in the general region, nor increase demand for recreation. The net effect of the proposed project on agricultural lands is that about 15 acres of land will be permanently converted to right-of-way for new and modified canals. This is the result of permanent conversion of 22 acres to right-of-way, offset by (a) enhancement of agricultural land at the 2 borrow sites and (b) offset by enhanced irrigation facilities. Much of the agricultural land needed for right-of-way for the new and modified canals is now disturbed, consisting of perimeter access roads along the existing canals. The net amount of land currently in production and affected by the proposed project will thus be less than 15 acres. This is approximately 0.01 percent of the total acreage in production within RD 108. 3.6.3 Environmental Consequences of No Action The No Action Alternative would have no impacts to land use and planning. 3.7 Cultural Resources 3.7.1 Affected Environment 3.7.1.1 Potential Area of Effect From the perspective of cultural resources, the potential area of effect (PAE) for the project is limited to sites where construction activity will involve excavation of previously undisturbed soils and/or where above-ground structures will be removed or modified. Elements of the Proposed Project that do not meet these criteria include:
The PAE for the Proposed Project thus consists of the following areas:
3.7.1.2 Cultural Setting In pre-history, an abundance of natural resources in the Sacramento River Valley supported large numbers of native peoples and there is evidence of high population densities in the valley. Prior to European contact, the Sacramento and San Joaquin valleys were characterized by massive wetland complexes surrounded by dry, often desert-like, grasslands and scrublands. At Euro-American contact, the Native Americans that lived in the area settled in close proximity to the major rivers, occupying permanent or winter settlements of 15 to 20 individuals (Moratto 1984). Native American archaeological sites in the region including the proposed project area tend to be on alluvial terraces or fans adjacent to the Sacramento River. At these locations, Native American peoples had access to abundance fish, wildlife, and plant foods. The project area contains terraces adjacent to the Sacramento River. Given the environmental setting of the project area, Native American sites would generally be expected in the general project area, and numerous sites are recorded within several miles of the Proposed Project facilities. Most of the known sites are on the east side of the river, on marginally higher ground. On the western side of the river in the vicinity of the Proposed Project, known prehistoric cultural sites include 5 historic middens. Of these, one is in the PAE. The remaining middens are 500 to 2500 feet outside of the PAE. Within the PAE, CA-COL-2 (Locus A and Locus B) is a large midden mound on the landward side of the Sacramento River levee, about 4 meters high, 130 meters long, and 100 meters wide. It was first recorded in 1934. There is some confusion about the location of the site, and thus there are two recorded loci (about 0.5 miles apart). The only site which has the characteristics of a large midden mound is the southern site. The northern locus recorded for this site does not have midden mound characteristics and currently consists of a flat agricultural field. The mound at the southern locus (CA-COL-2, Locus A) was partially excavated in 1935 and found to contain ash lenses, house pits, and at least 60 burials. This mound should be considered a highly significant prehistoric resource. The Locus A site is currently occupied by a mobile home and there are several concrete pads in place as well. The existing RD 108 canal and access road runs along the base of this mound and was constructed in part with materials from the mound. Following the arrival of the Spanish in 1772, the proposed project area remained somewhat isolated from European influence because of its distance from San Francisco and frequent flooding conditions within the Proposed Project area. Permanent Spanish-era settlements are thus unlikely in the Proposed Project area. European settlement of the area north of Sacramento begins in earnest following discover of gold (1849), which resulted in a significant influx of people to California, although cities and towns were generally located on high ground outside of the floodplain-marsh complexes of the Sacramento River. The river functioned as a transportation corridor, but itself was affected by mining and upstream development as millions of cubic yards of sediment from gold mining operations was transported from the mountains to the floodplain and river. The present configuration of the valley floor is the result of land reclamation efforts that began in the early 1900's, when levees were constructed along the major rivers and streams and the marshes of the historic floodplain were drained and converted to agricultural uses. In the Proposed Project area, development generally occurred following these reclamation efforts. Historic records search identified four known historic resources, including RD 108's 2047 Pump House, the El Dorado Ranch, the Colusa Drainage Canal, and an old-growth oak grove. None of these known resources are within the PAE, the closest being about 1,500 feet from the borrow site along the Main Drain. Within the PAE, the only structures over 50-years in age which may be affected by the Proposed Project are:
The existing irrigation canal system has been modified and routinely maintained during the past 50 years on a regular basis. Both of the historic pumping plants over 50 years in age (Boyers Bend and Tyndall Mound) were evaluated to determine with they would be considered eligible for listing on the National Register of Historic Places (National Register), based on evaluation of 4 criteria:
Although the two pumping plants are associated with the regional reclamation programs that resulted in the conversion of historic marshes to agricultural uses, the plants themselves do not meet the remaining criteria for listing in the National Register. All three pumping plants were recorded on Department of Parks and recreation site forms. 3.7.2 Environmental Consequences of Proposed Action As noted in the letter from the State Historic Preservation Office (SHPO; Appendix A), it is probable that there are Native American and/or historic cultural resources within the general region covered by the SHPO literature review, specifically along portions of the canal alignments. Although pedestrian surveys conducted in 2004 found no evidence for previously unrecorded prehistoric artifacts, two isolated artifacts were observed. A projectile point was found on the west side of a small irrigation ditch about 1,500 feet from the Combined Pumping Plant and Fish Screen and a stone pestle with evidence of scaring from agricultural machinery was found in the concrete-lined canal between Howells Landing and Tyndall Mound. In some instances, crops obscured surveyors. Because prehistoric peoples are known to have occupied the Proposed Project area for an extended period of time, subsurface excavations in the new canal alignments have moderate to high probability of encountering significant buried prehistoric cultural resources. In the vicinity of CA-COL-2 (Locus A), the known extent of potentially significant prehistoric resources extends from the base of the mound itself to the Canal/Access Road. To the landward side of the access road, the ground is an actively farmed field and surface evaluations of the site found no surface evidence of prehistoric cultural resources. The Proposed Project provides for the existing canal and road to be covered following construction of a new canal segment which will be connected to the existing canal from 50 to 150 feet north of the site, run across the open agricultural field 50 to 150 feet from the known boundary of the Locus A site, and the connect to the existing canal 50 to 150 feet from the southern end of the Locus A site. As a result, the Proposed Project will be outside of and will not affect the known CA-COL-2 Locus A site. However, the existence of a large midden site is an indicator of continuous prehistoric occupation, and subsurface excavations for the new segment of canal have a probability of encountering buried prehistoric cultural resources. Because the Proposed Project is located in the historically active Sacramento River floodplain which has experienced significant recent sediment deposition, it is not likely that excavations for construction will reach depths at which paleontological resources will be found. No project effects on paleontological resources are anticipated. 3.7.3 Proposed Mitigation 3.7.3.1 General Prior to construction, USBR and RD 108 will consult with the State Historic Preservation Office (SHPO) to develop procedures for (a) protection and avoidance of known cultural resources, (b) evaluation and treatment of unexpected subsurface cultural resources (including Native American burials), (c) construction monitoring requirements, (d) detailed reporting requirements, and (e) curation of any cultural materials collected. These procedures will be defined in a Historic Properties Treatment Plan (Cultural Resources Management Plan) or in another suitable format as directed by the SHPO. The procedures will ensure compliance with all of the relevant requirements of the Historic Preservation Act and of California Environmental Quality Act Guidelines Section 15064. The procedures will specifically define construction practices and monitoring requirements for areas within 100 feet of known/recorded cultural sites, including flagging of the site as an Environmentally Sensitive Area and exclusion of all construction activities from the flagged area. Procedures will also include:
3.7.3.2 Effects at CA-COL-2 (Locus A) In consultation with a qualified archeologist, RD 108 has designed the Proposed Project to avoid effects to the CA-COL-2 (Locus A) site by abandoning the existing canal and access road, re-routing the canal around the known boundary of the site, and providing for the existing canal and access road to be covered to protect resources which may be in these structures. In addition to this impact avoidance measure, RD 108 would:
3.7.3.2 Effects after Mitigation The combination of preconstruction training of construction personnel, continuous construction monitoring in the vicinity of known cultural resource sites, and intermittent construction monitoring in other construction areas where subsurface disturbance is possible during construction will serve to achieve compliance with monitoring and notification requirements of Section 106 of the National Historic Preservation Act, the California Environmental Quality Act, and the California Health and Safety Code regarding treatment of human remains. The procedures outlined for avoidance and minimization of impacts to known cultural resources and procedures for resources treatment, recovery, and curation developed during consultation among USBR, the SHPO, RD 108, and Native Americans will reduce potential impacts to known cultural resources to a level of less-than-significant under the California Environmental Quality Act. The already accomplished recordation of the three existing water diversions will reduce potential impacts associated with removal of these structures to a less-than-significant level. |