MITIGATED NEGATIVE DECLARATION - PROPOSED
This report is presented in its entirety with the exception of several tabular checklists and illustrations. Summaries and findings from these checklists are included. Information presented here may be subject to change. Please contact the Dunsmuir Garden Club for the latest information.
City of Dunsmuir
5915 Dunsmuir Avenue
Dunsmuir, CA 96025
PROJECT: The proposed project entails construction of a new park and trail system in the City of Dunsmuir as well as restoration of adjacent meadow and floodplain areas. The ±8.7-acre site will contain about 3 acres of community park facilities, a 2-acre meadow restoration area, about 2.5 acres for levees and floodplain restoration, and about 1.2 acres for roads and upland habitat. Facilities will include two picnic sites, portable toilets, access for whitewater boating, parking for 19 vehicles, about 1000 feet of trail paralleling the river and another 500 feet of interior trails and sidewalks.
LOCATION: The proposed park will be located in Siskiyou County, California, within the City of Dunsmuir between Upper Soda Springs Road and the Sacramento River. The site is in the south-central portion of Section 24, Township 39 North, Range 4 West. (See Figure 1 of the Initial Study)
PROJECT NAME: Tauhindauli Park and Trail Project
As documented in the Initial Study, project implementation could result in temporary disturbance of riparian habitat and wetlands; disturbance of nesting migratory birds; possible disturbance of cultural resources; temporarily increased soil erosion and water quality degradation; increased traffic volumes on substandard roads; and increased noise levels and dust emissions during construction. Mitigation measures have been formulated to reduce these impacts to levels that are less than significant. Because the City of Dunsmuir will adopt mitigation measures as conditions of project approval and will be responsible for ensuring their implementation, it has been determined that the project will not have a significant adverse impact on the environment. A mitigation monitoring program will also be adopted and implemented by the City of Dunsmuir.
TAUHINDAULI PARK AND TRAIL PROJECT
1. Project Objectives and Proposed Improvements
The Dunsmuir Garden Club is proposing to develop a ±8.7-acre site in the City of Dunsmuir with a community park and trail system. The site is situated between Upper Soda Springs Road and the Sacramento River. The Garden Club does not own the land, but has leases and landowner agreements to proceed with the proposed development. The landowners are the City of Dunsmuir, State of California, PacifiCorp (previously Pacific Power and Light Company), Union Pacific Company and John W. and Patricia W. Rhinesmith. In addition to these lands, the Garden Club is attempting to obtain two small additions to the park site: Soda Springs, located on the north side of Upper Soda Springs Road, and a small extension at the east end of the site, which would be used to provide handicap fishing access. The project site and the two possible additions are shown in Figures 1, 2 and 3. Site plan details are illustrated on a map available for review at the Dunsmuir City Hall, Dunsmuir Branch Library and The Upper Sacramento River Exchange.
The Garden Club's objectives are to create a park and trail system that is ecologically viable, benefits local residents, is handicapped-accessible, provides historic restoration and interpretation, and promotes tourism. These objectives fit into the three main project components: 1) ecological restoration of the site, 2) recreational facilities development, and 3) infrastructure improvements. About 3 acres of the site will be used for park facilities, about 2 acres will be devoted to meadow restoration, 2.5 acres will be used for levee reconstruction and floodplain restoration and about 1.2 acres will be used as road and upland habitat.
Ecological restoration activities proposed for the project will focus primarily on the Sacramento River floodplain, a small unnamed stream and approximately two acres of meadow west and north of the substation. The goals of floodplain restoration are to restore the topography to approximate historic floodplains along the river and to re-establish associated riparian woodland vegetation. Floodplain restoration will occur at two sites within the project area. At the upstream site, an existing levee will be relocated and the grade of the adjacent meadow will be lowered. This work will compensate for historic floodplain loss, when the river channel was moved to accommodate railroad realignment in the 1930's. At the downstream site, fill material will be removed from the historic floodplain between the I-5 and Dunsmuir Avenue bridges.
Some of the fill removed from the floodplain will be used to improve the berm protecting the Rhinesmith's house and to create a new berm to protect PacifiCorp's on-site electrical substation from flooding. Mechanized equipment will be used for fill removal and levee construction as well as for removal of exotic vegetation. Work will occur no closer than five feet from the edge of the river. The disturbed areas will be revegetated with indigenous riparian species.
Stream restoration will include re-routing the unnamed channel from the culvert west of I-5 through the restored floodplain. The streambanks will be vegetated with indigenous riparian species.
Approximately two acres of meadow in the western portion of the site will be restored. Exotic species such as Himalayan blackberry will be removed by small tractor and hand, with minimal soil disturbance, and the disturbed areas will then be revegetated with indigenous meadow species.
Recreational facilities proposed for the site are two picnic areas, a graveled whitewater boating access area, portable chemical toilets, a concrete handicap-accessible fishing platform, and a 10-foot wide paved multi-use trail running the length of the park with connectors (6- to 8-foot wide) extending to the parking area, fishing platform and cobble beach on the river.
Infrastructure improvements will consist of construction of a paved parking area and changes to Upper Soda Springs Road. Upper Soda Springs Road currently has narrow pavement widths, steep grades and limited sight distances near the bridge undercrossings. The project proposal calls for the road to be improved between River Road and a point just west of the Dunsmuir Avenue bridge. Work will involve widening the road to 20 feet and re-aligning it to reduce the curve under the I-5 bridge. The road will also be raised under the I-5 bridge, which will reduce the steep grade of the adjoining road segment. The northern extension of River Road will also be widened and realigned to improve its intersection with Upper Soda Springs Road.
Access to the on-site parking area will be from the realigned portion of Upper Soda Springs Road. The paved parking area will accommodate 19 vehicles. Two of the parking spaces will be handicap-accessible. The parking area will incorporate an access road to the on-site substation. The access road will accommodate heavy equipment and vehicles that may be needed at the substation. Drainage from the parking area will be routed to a vegetative filter area in the river floodplain.
Principal funding for the project is being provided by grants from the Cantara Trustee Council and the Urban Streams Clean Water Act program. The existing grants include an endowment fund, which will be used to provide for long-term maintenance of the park. Additional funding may be obtained through other grants and/or 'Friends of Tauhindauli Park and Trail.' Grants that the Garden Club and City of Dunsmuir are currently pursuing would allow purchase of the two potential additions noted above as well as adjoining lands to the west. If lands to the west are acquired, possible improvements could include conversion of the existing residence to a small museum, expansion of the trail system, construction of permanent restrooms, and restoration of Upper Soda Spring and other features/structures associated with the historic Upper Soda Springs Resort.
This Initial Study addresses the proposed park site and two possible additions (the Soda Springs site and the potential handicap fishing access). Acquisition and development of the larger parcel to the west is speculative at this time and is not addressed in this study. If this land is acquired, a subsequent environmental document would be required.
2. Permits and Approvals
Prior to project implementation, discretionary permits and approvals will or may be needed from regulatory agencies, as listed below.
Certification by the City of Dunsmuir that the Initial Study/Mitigated Negative Declaration has been completed in compliance with the California Environmental Quality Act (CEQA), and has been reviewed and considered by the decision-makers.
Issuance of a Stream Alteration Agreement by the California Department of Fish and Game for work in the on-site streams and adjacent to the Sacramento River.
Issuance of an Individual ('404') or Nationwide Permit by the US Army Corps of Engineers for work undertaken within wetlands and other waters of the United States.
Issuance of a General Construction Activity Storm Water Permit and Water Quality Certification by the California Regional Water Quality Control Board, North Coast Region.
Issuance of an encroachment permit by Caltrans for work undertaken within the Interstate 5 right-of-way.
Issuance of a use permit by the City of Dunsmuir for siting of the park in area currently zoned R1.
The proposed park site is located within the Upper Sacramento Canyon and is adjacent to the Sacramento River. The dominant vegetation types in the area are mixed conifer, oak woodland, montane chaparral, riparian woodland and wet meadow. The surrounding area contains medium- and low-density residential development with some areas of dense tree cover.
The site is undeveloped except for the PacifiCorp substation (15,000 sq. ft.) and the City of Dunsmuir's sewer pump station (435 sq. ft.). The site is fairly open with most of the taller vegetation being concentrated in narrow bands along the river and on the steep slopes along Upper Soda Springs Road. The riverside vegetation consists of riparian species dominated by cottonwood, alder and willow, while the roadside vegetation consists of upland species dominated by Douglas fir, incense cedar, black oak and canyon live oak. The meadow area in the western third of the site contains many clumps of exotic Himalayan blackberry and native willows.
The elevation of the project site varies from approximately 2310 feet above sea level along the Sacramento River to approximately 2355 feet above sea level near the Upper Soda Spring outlet. The topography of the site is primarily flat with moderately steep sections along the banks of the river and to the north of Upper Soda Springs Road. The site has approximately 1600 feet of river frontage. A flood control levee runs along a portion of the riverbank.
Soils on the majority of the site are mapped by the Natural Resources Conservation Service (USDA, NRCS, 2000) as Stoner gravelly sandy loam, 2 to 15 percent slopes. This unit is characterized by slow to medium surface runoff and a low to moderate hazard for water erosion. The western tip of the site, south of the Rhinesmith residence, is mapped as Neer gravelly sandy loam, 50 to 75 percent slopes (although on-site slopes are not nearly this steep). Runoff from the Neer soil unit is very rapid and the hazard of water erosion is high to very high for this soil unit.
Most of site has been heavily disturbed in the past by use associated with the historic Upper Soda Springs Resort, construction of the I-5 and Dunsmuir Avenue bridges, river channel dredging, construction of the substation, and recreational use. Current uses (aside from the substation and pump station) include fishing, swimming, raft and kayak put-in, picnicking and dispersed recreation.
The project site has been highly disturbed in the past, which has greatly reduced its visual quality; the site is even identified as an 'eyesore' in the City of Dunsmuir General Plan (1985). Nonetheless, the site has a high aesthetic potential, primarily because of its proximity to the Sacramento River.
Project implementation will enhance the visual character of the site through landscaping, habitat restoration, weed control, visual screening of the substation, confining vehicle traffic to designated parking areas, and by emphasizing views of the river. The park will not include any night lighting nor are the planned facilities expected to create significant glare.
There are no lands designated as Farmland or zoned for agricultural use within the site or surrounding area. (California Department of Conservation, Division of Land Resource Protection, 1998; City of Dunsmuir, 1985)
The proposed project is located in the Northeast Plateau Air Basin. Air stagnation in the area is rare due to the small population and mountainous terrain. According to Siskiyou County Air Pollution Control District staff (E. Beck, Siskiyou County APCD, pers. comm.), the basin is considered 'Attainment' or 'Unclassified' for all pollutants except particulate matter less than 10 microns in size (PM10). Project implementation would result in temporarily increased air emissions due to equipment emissions and earthwork. Although the emissions would include PM10, Siskiyou County APCD staff has stated that impacts on air quality would be insignificant if particulate matter generation is properly controlled by implementing standard construction practices such as watering the disturbed soils, as called for in Mitigation Measure 1. In the unlikely event that dust generation is excessive, the Siskiyou County Air Quality Management District has the authority to require/enforce additional dust control measures.
In the long term, air emissions attributable to project development are not anticipated to increase significantly. Although more vehicle traffic may be attracted to the site, the parking area and access routes will be paved, which will reduce PM10 emissions.
Potential effects of project implementation on biological resources were evaluated through review of the California Natural Diversity Data Base records (DFG, 2000), discussions with Department of Fish and Game (DFG) staff and field reconnaissance. Work included a botanical field survey, wildlife evaluation and delineation of waters subject to US Army Corps of Engineers jurisdiction.
The dominant vegetation types in the project vicinity are mixed conifer/oak woodland and riparian. The project site likely supported these vegetation types in the past, but only remnants of these communities are currently present. Current on-site vegetation types include a narrow band of riparian forest along the Sacramento River, a wet meadow ringed by riparian scrub vegetation, mixed conifer/oak woodland, and an opportunistic mix of natives and exotics in the most highly disturbed portions of the site.
The riparian forest association occurs as a roughly 30-foot wide band along the Sacramento River. Vegetation nearest the river is characterized by herbaceous species such as sedges, with alder, black cottonwood, big-leaf maple and willows further inland. Similar riparian species occur in some of the wetlands north of Upper Soda Springs Road, along with black locust, cattail, rushes and dock. The riparian scrub association consists primarily of Himalayan blackberry and willows. It is most abundant adjacent to the wet meadow, but also occurs in other on-site wetlands. The wet meadow is characterized by perennial grasses such as orchard grass and bentgrass interspersed with patches of Himalayan blackberry and willows.
Lands to be developed with the core park facilities have been subjected to extensive disturbance, including uncontrolled vehicle access. Much of this area is denuded and has compacted soils. Vegetation consists of some natives such as incense cedar, big-leaf maple and wildrye as well as numerous introduced species such as chicory, fennel, English plantain, starthistle and others. The mixed conifer/oak woodland association is most abundant at the far eastern and western ends of the project site. Species present include canyon live oak, Douglas fir, incense cedar and black oak.
Potential impacts of the project on plant communities are not considered significant. Work will be concentrated in areas that have been subjected to the most disturbance. Although some riparian vegetation will be removed during relocation of the levees, floodplain restoration work will result in a net increase of riparian habitat. Likewise, the planned removal of exotic species and restoration of the meadow and streams will further enhance on-site habitats. Further information regarding the proposed planting program and monitoring plan is presented in Appendix A. Because the project proposal includes significant restoration work, no further mitigation is necessary with respect to plant communities.
Wetlands and Other Water of the United States
The US Army Corps of Engineers has jurisdiction over 'Waters of the United States.' The definition of these waters is quite broad and includes streams, rivers, ponds, lakes and wetlands such as marshes, bogs, seeps, vernal pools, and wet meadows. Wetlands may be only seasonally saturated or inundated, but typically support specially adapted vegetation and have hydric soils (US Army Corps of Engineers, 1987).
The project site contains several occurrences of waters subject to Corps jurisdiction. These consist of the Sacramento River, Upper Soda Springs and its outflow channel, an unnamed drainage channel tributary to the river just west of the I-5 bridge, a narrow band of wetlands on the north side of Upper Soda Springs Road and a ±2-acre wet meadow-riparian scrub community to the west and north of the substation. The locations of these jurisdictional waters are shown on the site plan. Proposed activities that may affect jurisdictional waters include:
Restoration of the wet meadow-riparian scrub community west and north of the substation.
Rerouting the Upper Soda Spring outfall channel back to its historic location. (This work may be conducted as a subsequent phase of the project.)
Rerouting of the unnamed drainage channel.
Reworking the levees along the Sacramento River to restore portions of the historic floodplain.
Possible construction of a handicap-accessible fishing platform in or adjacent to the Sacramento River.
All work undertaken in wetlands or other jurisdictional waters will be in accordance with the standard terms and conditions of an Individual or Nationwide Permit issued by the US Army Corps of Engineers and a water quality certification issued by the Regional Water Quality Control Board. Conditions of the Section 1600 Stream Alteration Agreement to be issued by the Department of Fish and Game will also apply to all or most of the above activities. The standard conditions of these permits will minimize adverse effects on the jurisdictional waters; no additional mitigation measures are expected to be needed, particularly because wetland restoration and revegetation is included as part of the project proposal.
The standard permit conditions typically include:
Using appropriate soil erosion and sediment controls.
Prohibiting the disruption of the movements of aquatic life.
Prohibiting activities that result in the physical destruction of important spawning areas.
Removing all temporary fills and returning affected areas to their preexisting elevation.
Providing compensatory mitigation for all permanently impacted wetlands.
Prohibiting the discharge of petroleum products and excavated materials to surface waters.
Conducting activities during prescribed time frames.
Restoring streambeds and banks to their original contours.
Very few wildlife species were observed during the winter 2001, when field evaluations were undertaken. However, the project site is expected to support a number of wildlife species, particularly deer, small mammals and birds. Project implementation may result in short-term disturbance of wildlife and temporary loss of habitat; however, the project is expected to be beneficial to wildlife over the long term because it will entail significant habitat restoration.
Short-term impacts on wildlife could occur due to vegetation removal and increased erosion resulting from earthwork. The effects of vegetation removal are minimized because most work will be in the areas heavily disturbed by past activities. However, vegetation removal could potentially affect nesting migratory birds such as yellow-breasted chat, as discussed below.
The potential for erosion and subsequent sedimentation of the Sacramento River will be minimized because no work will occur within the active channel (with the exception of construction of the handicap-accessible fishing platform). Vegetation immediately adjacent to the channel will remain in place and will provide a minor amount of filtering for sediments that may be generated. Other erosion control provisions are discussed below under Section IV.8: Hydrology and Water Quality. According to DFG staff (T. Healy, pers. comm.) if standard erosion control measures, and any other conditions specified in the required Streambed Alteration Agreement are implemented, there should be no impacts to wildlife species within the river.
The local deer population may use the meadow area on the site for wintering and fawning. DFG staff (D. Smith, pers. comm.) stated that removal of Himalayan blackberry plants would not significantly affect the deer. The site has a low capacity to support fawning does, which require at least a 100-yard buffer separating them from other does at fawning time. Further, blackberries do not provide quality cover or forage for deer; the native vegetation that will be planted following blackberry removal is much more beneficial to the deer population.
Nesting Migratory Birds
Migratory birds are provided protection under the federal Migratory Bird Treaty Act, which established that all migratory birds and their parts (including eggs, nests, and feathers) are fully protected. To ensure that migratory birds are not adversely affected by project implementation, vegetation removal should be completed prior to arrival of the migratory birds or after the young have fledged. According to Department of Fish and Game staff, most birds nest between April 1 and July 15; removal of vegetation at other times of the year (July 15 through April 1) is unlikely to affect nesting (B. Deuel, pers. comm.). If vegetation clearance must occur between April 1 and July 15, a nest survey should be conducted prior to vegetation removal. This would consist of examining all suitable trees and shrubs for the presence of active nests. If active nests were present, removal of the supporting vegetation would have to be postponed until the young birds fledged. Steps to be taken to protect nesting migratory birds are prescribed in Mitigation Measure 2.
The special-status wildlife species reported from the Dunsmuir quadrangle consist of tailed frog, northern goshawk, black swift, pacific fisher, California wolverine, bilobed phyacophilan caddisfly and foothill yellow-legged frog. The plant species consist of Castle Crags harebell, Oregon fireweed, Castle Crags ivesia, pallid bird's-beak, thread-leaved beardtongue and Greene's mariposa lily. Based on the habitat types observed in the field and discussions with DFG staff (R. Lis, pers. comm.; B. Deuel, pers. comm.; T. Healy, pers. comm.), project implementation is not expected to adversely affect any special-status species.
One other special-status species, the yellow-breasted chat, could nest on the project site. The chat is a migratory species known to nest in blackberry thickets. The temporary loss of habitat due to removal of blackberries will not significantly affect the chat since the area will be replanted with native vegetation that the chat will also use for nesting activities. However, as specified in Mitigation Measure 2, removal of the blackberries should be conducted outside the nesting season unless a nesting survey conducted prior to vegetation removal shows that the birds are not present.
An archaeological records search and field survey were conducted by Coyote & Fox Enterprises in October and November 2000. All fieldwork was conducted in accordance with the guidelines of the State Historic Preservation Office and accepted professional standards.
The records search entailed review of archaeological records maintained by the Northeast Center of the California Historical Resources Information System at CSU, Chico. Other sources consulted included the National Register of Historic Places (NRHP), the California Register of Historical Resources, the California Points of Historical Interest, the California Historical Landmarks, the NE/CHRIS Historic Property Data File for Siskiyou County, and a Caltrans report documenting the NRHP evaluation of the 1916 Sacramento River Bridge/Overhead. Contacts were also made with local Native American representatives, Siskiyou County Historical Society, and various individuals interested in the project and knowledgeable about the ethnography and history of the area.
Records indicate that a portion of downtown Dunsmuir is listed on the National Register of Historic Places, but the project area had not been previously surveyed for cultural resources, and no sites had been previously recorded within the project area. However, the Upper Soda Springs Resort and the spring itself, which was used by native tribes, are known unrecorded sites in the project area.
As a result of the survey, two historic sites were documented. One site is identified as Upper Soda Springs Resort and will be assigned a formal identification number by the State of California. Features noted to date are: 1) the developed spring box, 2) stone walls, 3) remains of the footbridge which crossed the river from the train tracks, 4) a garage/shed structure and 5) a magnolia tree and fruit trees. The other site, identified as the 'Yellow Crane,' documents a tall metal crane painted yellow and the remains of an associated wood platform beneath. The Yellow Crane site is considered ineligible to the NRHP. The documentation completed for this survey is believed to have recorded the significant field information relative to the Yellow Crane site.
The 1916 Sacramento River Bridge/Overhead, the footings of which are within the project area, has been previously recorded. It has been determined ineligible for inclusion on the NRHP, due in part to widening and alteration of the bridge in the mid-1950s. Other potentially historic materials identified in the study area after completion of the initial field study include the remnants of a wooden diversion pipe used to provide water to the Copco Pelton Wheel and an old fire hydrant partially overcovered by Himalayan blackberries. Although neither of these features is expected to be significant with respect to the project site (the diversion pipe originated off-site and the hydrant is still in active use), they will be further addressed in an addendum to the cultural resources study report.
The Upper Soda Springs Resort site should be considered potentially eligible for inclusion on the National Register of Historic Places because of its local historical significance. However, due to previous disturbance and dense vegetation, the ground surface in many areas could not be adequately inspected for the potential presence of cultural resources. This archaeological survey, therefore, is not considered complete. It is quite likely that additional artifacts and features associated with the resort site are buried in the area and may be exposed as park development proceeds. The most likely areas are those around the spring, in the area west of the lawn and orchard, under the developed residential buildings and landscaping on the Rhinesmith property, and along (and perhaps under) the roads. Other areas of the project site may also contain prehistoric or historic cultural resources, such as the graveled area around the substation. Therefore, as specified in Mitigation Measure 3, a professional archaeologist will be contacted when initial vegetation removal and/or ground disturbance occurs in any portion of the project area. The professional archaeologist will make a determination as to whether the planned activities require monitoring. If monitoring is required, a qualified archaeologist will be on-site during the work to check for the presence of cultural resources.
An addendum report will be prepared upon completion of the archaeological field survey. The addendum will include documentation of any new archaeological sites and/or isolated artifacts and cultural features, as well as an addendum to the Archaeological Site Record for Upper Soda Springs Resort, if additional artifacts and features are found in association with that site. The addendum may also include additional mitigation measures to cover additional survey findings and/or changes in park design.
It is possible that potentially significant subsurface cultural materials could be encountered during construction activities when an archaeologist is not present. As called for under Mitigation Measure 4, if subsurface cultural materials are encountered during construction, all ground-disturbing activities will be halted in the vicinity until a qualified archaeologist can examine the materials, make a determination of their significance, and recommend/implement further mitigation measures as needed.
Data reviewed to evaluate the potential for soil and geologic hazards at the project site included the City of Dunsmuir General Plan (1985) as well as geologic and soils mapping (California Department of Conservation, Division of Mines and Geology, 1997; USDA, Natural Resources Conservation Service, 2000). The City of Dunsmuir is situated about 2300 feet above sea level in the canyon of the Sacramento River. Since the area is bisected by the Upper Sacramento River, the predominant rock type is recent alluvium.
The City of Dunsmuir General Plan identifies four faults in the vicinity of the city, none of which underlie the project site. The General Plan states that ground rupturing is not thought to be a serious concern, however landslides and subsidence resulting from ground shaking may be of concern. The General Plan does not indicate areas of subsidence, but shows two recurring landslide areas in the vicinity of Tauhindauli Park. One of these is south of the park, on the opposite side of the Sacramento River and will not affect project implementation. The second is located east of Interstate 5, near the intersection of Upper Soda Springs Road and River Avenue. The project engineer noted that the slide area is east of the intersection and would not affect or be affected by the planned intersection improvements (C. Schlumpberger, Schlumpberger Engineering, pers. comm.).
Two soil units have been mapped on the site (USDA, Natural Resources Conservation Service, 2000). The most prevalent soil type is Stoner gravelly sandy loam, 2 to 15 percent slopes, which is mapped as occurring throughout all but the far western tip of the project site. The other soil type mapped on the site is Neer gravelly sandy loam, 50 to 75 percent slopes. Table 2 summarizes the characteristics of these soil types.
Although the majority of the site is on nearly level to gently sloping land with low to moderate potential for soil erosion, project implementation has some potential to cause increased soil erosion and subsequent sedimentation of the Sacramento River. Of most concern would be creation of bare soil surfaces near the river as a result of levee relocation and floodplain restoration activities. Other disturbed areas will be better protected from high flows and erosive action. Proposed erosion control measures are discussed under Section IV. 8: Hydrology and Water Quality.
Hazards and Hazardous Materials
The potential for the project site to have been impaired by the release of hazardous materials was investigated through review of federal, state and local records as well as field inspection. No evidence of hazardous materials release was observed during the site inspection. As documented in Table 3, three facilities within a half-mile radius of the project site are known to have had releases of fuel from underground storage tanks. One release, at the old Dunsmuir Elementary School, affected soil only; this case has now been closed. The other two releases affected groundwater. One of these cases involved a release of diesel at the Cave Springs BP station. Remediation has been undertaken and post-remediation groundwater monitoring is now occurring. The release occurred about 1500 feet upstream from the project site; because of the distance separation and status of remediation efforts, this release is not expected to adversely affect the subject site. The other release, at Frank's Shell, is currently being investigated. Although the extent of the release is undetermined, it occurred 1800 feet down-gradient of the subject site and thus has no potential to adversely affect the subject site.
Project implementation will not involve routine use, transport or disposal of hazardous materials, create a significant risk of hazardous materials release, create significant safety hazards, interfere with implementation of emergency response plans or significantly increase the threat of wildfires. However, fuels and hazardous materials may be used on the site during project construction. As noted in Section I.2 of this document, a Storm Water Pollution Prevention Plan (SWPPP) acceptable to the Regional Water Quality Control Board must be prepared prior to construction. The SWPPP must establish provisions for dealing with hazardous materials and other contaminants. Given these existing requirements and the low potential for a release of fuels or other hazardous materials, no mitigation measures are warranted.
Hydrology and Water Quality
Project implementation will not affect groundwater quantity or quality, increase the exposure of people or property to flooding, or violate water quality standards or waste discharge requirements. However, the project will alter existing drainage patterns, could create minor increases in stormwater runoff, and has the potential to temporarily degrade water quality due to increased erosion.
Proposed project elements that could affect hydrology and water quality include relocating the onsite stream channels; reworking the levees along the Sacramento River to restore the historic floodplain; and paving of the access road, parking lot and principal trails, which could increase site runoff. A hydraulic study addressing potential effects on flood levels has been completed by Hydmet, Inc. (2001). This involved use of site-specific surveyed river cross-sections and previous flood-flow data in conjunction with the US Army Corps of Engineers' HECRAS computer model. The calibrated model was used to determine the 100-year water surface elevations for pre- and post-project conditions.
The study showed that the existing 100-year flood elevations differ slightly from those mapped by the Federal Emergency Management Agency (FEMA) due in part to the greater accuracy of the current mapping as well as to channel changes over the past 25 years since the FEMA survey. Modeling showed that main channel velocities during the 100-year flood event would range from 11 to 21 feet per second, which would flatten exposed vegetation and move even extremely large boulders. Highest velocities would occur at and immediately downstream of the Interstate 5 bridge. After project implementation, the lowest velocities would occur in the restored floodplain area, which would have a wider channel and be outside of the main current. Projected velocities in the floodplain restoration areas are 3 to 7 feet per second.
Modeling also demonstrated that project implementation would not significantly alter the 100-year flood elevations. The post-project flood elevations would remain unchanged from the pre-project condition at the lowermost three of the ten cross-sections studied, be up to 0.3 foot higher at two cross-sections and be up to 1.6 feet lower than the pre-project condition at the other five cross-sections. These changes are not considered significant (J. Humphrey, pers. comm.).
The planned levee work will not increase flooding with respect to the Rhinesmith residence, railroad tracks, substation, roads and/or other existing facilities. Instead, relocating and raising the levees will reduce the potential for flooding, particularly with respect to the Rhinesmith residence and substation. Further, provision of levees around the City's sewage pump station and manholes will minimize the potential for release of raw sewage into the river as a result of pump failure.
Although the project will increase stormwater runoff due to overcovering of the parking area, access roads and some trails with impervious surfacing, this minor effect will be offset by the creation of berms that will tend to slow the flow of runoff.
Project implementation is expected to result in increased erosion in the short term, until disturbed areas are sufficiently vegetated. In the long term, the potential for erosion may decrease because the floodplain will be widened, decreasing overbank flow velocities. Measures to minimize soil erosion have been developed for specific project activities by Tom Hesseldenz and Associates and are presented in Appendix B. Most of the measures are quite standard, calling for earthwork to occur in the dry season with the disturbed areas being planted, mulched with weed-free straw and irrigated for the remainder of the dry season. Monitoring will be conducted for five years, with any dead plants being replaced.
A different procedure will be implemented in the planned floodplain restoration areas. Excavation will be completed during the 2001 dry season. The finished grade will be left in a compacted state rather then being ripped or loosened to promote revegetation, and no topsoil will be imported. The exposed soil will be covered with weed-free straw. The straw will be criss-crossed with large branches and small trees saved from site clearing, which will be staked and wired in place. The floodplain restoration areas will be allowed to go through the winter with this surface cover. This should promote deposition of good planting soil and will eliminate the possibility of high flows washing out planted material. The areas will be planted with containerized and transplanted plants in the Spring 2001. The plants will be irrigated throughout the first dry season. Plants that die or are washed out will be replaced as needed for five years, and the stakes and wires will be removed after five years. This plan has been reviewed with Department of Fish and Game and Regional Water Quality Control Board staff and found to be appropriate and feasible, given the anticipated velocities in the river (T. Healey, DFG, pers. comm.).
Land Use and Planning
The project site is currently used for dispersed recreational activities and as open space. Recreational activities include fishing, swimming, walking, kayaking, rafting and picnicking. Roughly two-thirds of the lands planned for core park facilities are nearly devoid of vegetation because of unrestricted vehicle access. Woody vegetation is most abundant in the eastern tip of the site and along the riverbank. The proposed meadow restoration area currently receives only minimal human use, although it is adjacent to the historic Soda Springs Resort site. It consists of a meadow with extensive patches of Himalayan blackberry and some willows.
Lands in the vicinity of the study site are used primarily as open space or for residential use and transportation corridors. The nearest residence is just west of the proposed meadow restoration site. Additional single-family residences are present on the north side of Upper Soda Springs Road. About a dozen residences are within 250 feet of the project site. Nearby transportation corridors include Upper Soda Springs Road, River Road, Interstate 5 and Dunsmuir Avenue (the latter two extending over the site on bridges) and the Union Pacific Railroad on the opposite side of the river.
The proposed project is in conformance with applicable plans and policies for the area, including the City of Dunsmuir General Plan land use designations and zoning, and is compatible with surrounding land uses (City of Dunsmuir, 1985; M. Powers, City of Dunsmuir, pers. comm.). Accordingly, no adverse effects with respect to land use and planning issues are anticipated and no mitigation measures are warranted.
The City of Dunsmuir General Plan (1985) does not identify any important mineral resources on or near the project site.
Noise levels are typically measured on a logarithmic scale called the decibel (dB) scale. To approximate the response of the human hearing system, noise levels are measured on the 'A-weighted scale' which de-emphasizes the importance of low and extremely high frequencies that are not readily heard by humans. The A-weighted noise level is expressed as 'dBA.' Daytime noise levels of less than 40 dBA are generally perceived as quiet, 60 dBA as moderate and greater than 70 dBA as loud. Several noise rating methods have been developed to describe average noise levels over a given time period. The Equivalent Sound Level (Leq) is the equivalent, steady-state sound level that would contain the same acoustic energy as fluctuating noise levels measured over a given time period (the average noise level over a given time period). Leq is reported in units of dBA. The Day-Night Average Sound Level (Ldn) is a rating system that accounts for increased human sensitivity to nighttime noise. The Ldn is a single number rating reported in dBA that describes the perceived average noise level over a 24-hour period by splitting that period into a daytime period (7 AM – 10 PM) and a nighttime period (10 PM – 7 AM). Nighttime noise levels are weighted with a 10 dBA increase to reflect the increase in human sensitivity during these hours.
The noise environment of the study corridor is dominated by traffic noise from Interstate 5 and, to a lesser extent, Dunsmuir Avenue. Trains on the Union Pacific Railroad tracks south of the Sacramento River generate higher noise levels than freeway traffic, but are only intermittently present. Other noise sources in the vicinity include the PacifiCorp substation as well as natural sources such as wind and water. Noise-sensitive users near the study area include residents to the immediate west of the park site and those to the north of Upper Soda Springs Road.
Suitability of the Site for Recreational Use
On-site noise measurements confirmed that the noise environment of the subject site is suitable for recreational use. Although the City of Dunsmuir General Plan does not indicate noise levels acceptable for recreational development, 70 dBA Ldn is generally considered acceptable for parks, without mitigation measures (State of California, Office of Planning and Research, 1990).
Long-duration on-site noise measurements from which an Ldn could be calculated were not possible due to strong breezes that significantly raised therecorded noise levels. Nonetheless, during lulls, representative noise measurements were obtained. These indicated that the Sacramento River (under moderate flow conditions) generates a noise level of about 66 dBA at a distance of 30 feet from the water's edge. Between the Interstate 5 and Dunsmuir Avenue bridges, lows ranged from about 64 dBA near the river to about 60 dBA near Upper Soda Springs Road. Trucks typically generated noise levels of about 68 dBA, but were occasionally up to 72 dBA. Noise levels were lower east of the bridges in the vicinity of the planned picnic area, ranging from about 58 to 65 dBA. The substation was found to generate a noise level of about 57 dBA at its fenceline.
No trains passed the study site during the monitoring period. However, based on data from the City of Mt. Shasta General Plan (1993), trains on the UPRR mainline are expected to generate a noise level of about 65 dBA Ldn at a distance of 240 feet. This approximates the location of the planned multi-use trail paralleling the river; all of the other developed park facilities, including the picnic areas will be outside this noise contour.
In summary, the park site has a relatively high ambient noise level due to more or less continuous freeway traffic and intermittent train operations. Although some trucks and all train operations will cause on-site noise levels to exceed 70 dBA, average noise levels will be below 70 dBA, which is considered acceptable for recreational uses.
Short-term Construction-Related Noise Impacts
Short-term noise impacts on nearby residents may occur during project construction. Construction equipment typically generates on the order of 80 to 95 dBA at a distance of 50 feet, but the noise level decreases significantly with increasing distance from the source. At a distance of 200 feet, peak noise levels would range from about 67 to 82 dBA. Residences in the site vicinity are at least 200 feet from the principal on-site work areas or are topographically shielded from these areas, so actual noise levels experienced at the residences would be less. Compliance with Mitigation Measure 6, which limits construction to the daytime hours of 7 AM to 7 PM, will adequately mitigate the potential for short-term noise impacts on residents.
Long Term Noise Impacts
In the long term, noise impacts could result from increased traffic and increased on-site recreational activities. Recreational opportunities offered at the site will be passive (picnicking, walking, raft put-in, etc.) and not generate excessive noise levels. Further, the relatively high ambient noise level caused by freeway traffic will serve to mask noises generated on the site. Consequently, on-site noise generation is not expected to be significant and no mitigation measures are warranted.
Traffic noise on Upper Soda Springs Road has been projected by incorporating data from the traffic analysis (wba Engineering, 2001) into the Caltrans LEQV2 traffic noise model. The traffic analysis predicts that peak-hour traffic volumes on Upper Soda Springs Road may increase from about 68 vehicles under the pre-development condition to about 82 vehicles following project completion. This would raise the traffic-related noise level on Upper Soda Springs Road from 46 dBA to 47 dBA. This increase is not significant and no mitigation measures are warranted with respect to traffic-related noise generation.
Population and Housing
Project implementation will not displace existing housing or induce substantial population growth.
Project implementation may result in a minor increase in the need for maintenance of public facilities (e.g., roads) as well as a possible increase in demand for police services. Because an endowment fund has been established to provide for long-term maintenance of the park, effects on the City's maintenance abilities are not significant. The Dunsmuir Fire Chief (M. Cascarina, pers. comm.) has commented that the proposed project will benefit fire protection services in the area because plans include relocating some fire hydrants to more accessible sites. Public schools will not be adversely affected; to the extent that schools are able to use the facilities in conjunction with their curricula, the net effect may be beneficial.
The proposed facilities have some potential to generate a demand for police services. However, because the site is currently used for dispersed recreation and has uncontrolled access, the demand for such services is not expected to change significantly. Because the project will result in better control of access (the parking lot entrance will be gated at night), the need for such services could decrease. Siskiyou County Sheriff's Department has been involved in the planning process for the park and has made recommendations for lighting and parking lot/road orientation for safe ingress/egress. Department staff (M. Rokes, pers. comm.) commented that although they would prefer that night lighting be installed, the park is acceptable without lighting. No mitigation measures are warranted with respect to public services.
Project implementation will provide increased recreational opportunities in the City of Dunsmuir, which is considered a beneficial effect. Although maintenance will be required for the facility, an endowment fund has been established to provide for long-term maintenance needs. Thus, the proposed project is not expected to diminish the ability of the City to maintain existing facilities.
The Park and Trail project has some potential to create adverse effects on the environment; however, implementation of mitigation measures presented in this Initial Study will ensure that such impacts are not significant.
A traffic impact analysis addressing the project proposal has been completed by wba Engineering (2001). A complete copy of the report is on file with the City of Dunsmuir. The analysis focused on potential safety hazards and the potential for traffic delays at intersections used to access the project site.
Primary access to the park site is expected to be from Dunsmuir Avenue via Stagecoach Road and Upper Soda Springs Road. Additionally, some visitors may access the site from Dunsmuir Avenue via Sacramento Avenue and River Avenue. As a possible alternative route to the site, the traffic analysis also addressed access from Dunsmuir Avenue via Pioneer Way, Masson Avenue and Upper Soda Springs Road. Traffic volumes and turning movements at the three intersections with Dunsmuir Avenue were manually counted on August 17, 2001.
Trip generation rates for the Tauhindauli Park were based on data provided by the Institute of Transportation Engineers (1997). Trip generation rates reflect conditions on Sundays, which (for parks) have higher traffic flow than weekdays. For a 3.5-acre park and two picnic sites, Sunday trip generation is projected at 46 trips. Up to about 39 percent of the traffic (18 trips) may occur during the peak hour, and would be evenly split between entering and exiting vehicles. The number of parking spaces (19) limits the potential for special events with unusually high traffic volumes.
The traffic engineer assigned four of the peak-hour trips to the Pioneer Way intersection and 14 to the Stagecoach Road intersection. No trips were assigned to the Sacramento Avenue intersection because this access route is substandard. With these trip assignments, the delay at the Stagecoach Road/Dunsmuir Avenue intersection will increase on average from 9.2 to 9.7 seconds, while the average delay at the Pioneer Way/Dunsmuir Avenue will remain unchanged at 7.5 seconds. Delays of less than 10 seconds are indicative of smoothly operating intersection and are designated as providing a Level of Service 'A.' No intersection improvements are needed as a result of project implementation.
The traffic analysis determined that both Upper Soda Springs Road and Sacramento Avenue are deficient. Deficiencies noted regarding Sacramento Avenue are that it is narrow (16.5 feet) throughout and constricts to an effective width of 12 feet near its crest, where there is an old foundation adjacent to the street. Further, it is steep (13.6 percent grade) and has no gates at the railroad crossing. Accordingly, the engineer recommended that Sacramento Avenue be posted as unsuitable for trucks, buses, recreational vehicles and motor homes.
Deficiencies noted regarding Upper Soda Springs Road are that it has a substandard width (14 feet wide between the east side of the Interstate 5 bridge and River Avenue). Further, the grade on the hill east of the I-5 bridge is up to 15 percent and the curve under the bridges has limited sight distance. The project proposal calls for widening the road to 20 feet and for horizontal and vertical realignment of the segment below the bridges to improve sight distances and grades. The traffic engineer also recommends, and the City is expected to concur, that Upper Soda Springs Road be posted to prohibit on-street parking and that it and other roads proximate to the park be posted with a 15-mph speed limit. With these improvements, conditions on Upper Soda Springs Road would be acceptable for passenger vehicles, light-duty trucks and vehicles pulling small trailers. Maximum vehicle lengths were assumed to be 25 feet because parking for larger vehicles will not be provided and is not available elsewhere in the site vicinity. Mitigation Measures 7 and 8 summarize the recommendations of the traffic engineer.
Utilities and Service Systems
Project implementation may result in a minor increase in demand for potable water supply, wastewater disposal and solid waste disposal. Water will be used primarily for irrigation, although a drinking fountain may be provided in the picnic area. Portable toilets will be used on the site, with disposal services provided by a private company. Solid waste disposal will be provided by Clemens Waste Removal. Demand for such services is expected to be equivalent to one to two single-family households, and is not considered significant (J. Clemens, Clemens Waste Removal). No electrical service will be required. No mitigation measures are warranted with respect to utilities and service systems.
17. Mandatory Findings of Significance
This study revealed that the proposed project could potentially result in temporary disturbance of riparian habitat and wetlands; disturbance of nesting migratory birds; disturbance of cultural resources; increased soil erosion and water quality degradation; increased traffic volumes on substandard roads; and increased noise levels and dust emissions during construction. However, mitigation measures have been formulated to reduce these impacts to levels that are less than significant. Adoption and implementation of the mitigation measures presented in this report, or other equally effective measures, will ensure that the project does not result in significant adverse environmental impacts.
Control Particulate Matter Emissions. Particulate matter emissions shall be controlled by watering disturbed areas, including on-site vehicle/equipment travel routes; curtailing earth-moving activities on windy days; chipping vegetative debris or, if burning of vegetative debris is necessary, burning only on designated burn days; and/or by implementing other effective particulate matter control measures.
Avoid Effects on Nesting Migratory Birds. Disturbance of nesting migratory birds shall be avoided through proper timing of vegetation clearing activities. If vegetation removal occurs outside the nesting season (which typically extends from April 15 through July 15), no special measures are necessary. If vegetation clearing must occur during the nesting season, a migratory bird nesting survey shall be conducted prior to initiation of clearing. If active nests are present, they shall not be disturbed until the young birds are fully fledged.
Conduct Additional Cultural Resource Surveys. A professional archaeologist shall be contacted when initial vegetation removal and/or ground disturbance occurs in any portion of the project area. The archaeologist will monitor the work to check for the presence of cultural resources. An addendum report will be prepared when the archaeological survey is considered by the archaeologist to be complete. The addendum will include documentation of any new archaeological sites and/or isolated artifacts and cultural features, and an addendum to the Archaeological Site Record for Upper Soda Springs Resort if additional artifacts and features are found in association with that site. If sensitive cultural resources are found, the Dunsmuir Garden Club and its contractors shall implement additional mitigation measures recommended by the archaeologist.
Subsurface Cultural Resources. The Dunsmuir Garden Club shall notify the project contractor of the possibility of encountering subsurface cultural materials. If such materials are encountered, all ground-disturbing activities shall be halted within a 100-foot radius of the discovery until a qualified archaeologist can examine the materials, make a determination of their significance, and recommend/implement further mitigation measures as needed.
Implement and Monitor Erosion Control Measures. The erosion control measures presented in Appendix B shall be implemented in conjunction with project construction. Monitoring shall be conducted following each major storm during the first winter season to ensure that the control measures are effective. Any observed problems shall be promptly rectified.
Minimize Construction-Related Noise Impacts. Noise-level increases during project construction shall be minimized by confining construction to the hours between 7 AM and 7 PM, and requiring all vehicles and equipment to be equipped with mufflers in good condition.
Improve Upper Soda Springs Road. In addition to widening and improving the horizontal and vertical alignment of Upper Soda Springs Road, the road shall be posted by City of Dunsmuir staff to prohibit on-street parking and, with City Council approval, shall be posted with a 15-mph speed limit.
Discourage Use of Sacramento Avenue for Park Access. Sacramento Avenue shall be posted by the City of Dunsmuir as unsuitable for large vehicles such as trucks, buses, recreational vehicles and motor homes.
VI. Draft Mitigation Monitoring Program
Implementation of a mitigation monitoring or reporting program is required under CEQA whenever a public agency approves a project that may have a significant adverse effect on the environment and the agency requires modification of the project or implementation of mitigation measures to avoid or substantially lessen the adverse effects of the project. The requirement to prepare a mitigation monitoring or reporting program applies to projects for which either a mitigated negative declaration or environmental impact report has been prepared. The objective of the program is to ensure that the required modifications and/or mitigation measures are indeed implemented.
Monitoring and reporting may be conducted by the lead agency, or the agency may delegate its responsibility to another public agency or private entity that accepts the delegation. Nonetheless, the lead agency remains ultimately responsible for ensuring that the mitigation measures are implemented in accordance with the program.
The mitigation monitoring program described herein is designed to satisfy the monitoring program requirements as they relate to the adoption of specified environmental findings for the Tauhindauli Park and Trail Project. Monitoring will be carried out by City of Dunsmuir staff or the City's designated representative. Monitoring will involve review and approval of the construction bid package and other documentation, as well as site inspections, follow-up studies and/or other actions.
The following table identifies the specific measures recommended for adoption by the City, describes the monitoring actions to be taken and identifies the timing and frequency of monitoring actions. In some cases, a single review of written documentation will satisfy the monitoring requirement. In other cases, monitoring will involve site-specific resource surveys followed by periodic field checks during construction and beyond. The indicated monitoring frequency is a minimum; additional monitoring may be required as a condition of project permits or may otherwise be warranted, particularly if there are repeated violations of conditions.
Where inspection indicates that mitigation measures have not been fully implemented, the environmental monitor will submit a written description of all noted deficiencies to the Dunsmuir City Manager, who will be responsible for working with the Dunsmuir Garden Club and/or the contractor to remedy any lack of compliance. Following this, a verification inspection will be conducted and the results will be documented.
All inspection reports, noncompliance notices, and verification reports prepared following rectification of noncompliance will be kept on file at the Dunsmuir City Hall, located at 5915 Dunsmuir Avenue, Dunsmuir, California. The documentation will be kept up to date at all times, and will be made available to the public upon request.
City of Dunsmuir. 1985. General Plan and Environmental Impact Report.
City of Mount Shasta. 1993. General Plan Noise Element.
Coyote and Fox Enterprises. 2001. Archaeological Reconnaissance for the Proposed Tauhindauli Park and Trail Project on the Sacramento River, Dunsmuir, Siskiyou County, California.
Hydmet, Inc. 2001. Tauhindauli Park and Trail Project: Sacramento River Hydraulic Investigations.
State of California Department of Conservation, Division of Mines and Geology. 1997. Fault-Rupture Hazard Zones in California. Special Publication 42.
State of California Department of Conservation, Division of Land Resource Protection. 1998. Important Farmland Map.
State of California Department of Fish and Game. 2000. California Natural Diversity Data Base RareFind Printout, dated November 2000.
State of California Office of Planning and Research. 1990. State of California General Plan Guidelines.
U.S. Department of the Army, Corps of Engineers. 1987. Corps of Engineers Wetlands Delineation Manual. Technical Report Y-87-1.
U.S. Department of Agriculture, Natural Resources Conservation Service. 2000. Soil Survey of Intermountain Area, California, parts of Lassen, Modoc, Shasta, and Siskiyou Counties. U.S. Government Printing Office, Washington, D.C.
wba Engineering. 2001. Traffic Impact Analysis, Dunsmuir Garden Club, City of Dunsmuir.
VIII. Report Preparation Personnel and Persons Contacted
Report Preparation Personnel
Donald Burk, Environmental Services Manager
Cindy Luzietti, Environmental Planner
Jeff Perry, Graphic Designer
Keith Henderson, AutoCAD Technician
Denise Dethlefsen, Office Manager
Coyote and Fox Enterprises
Trudy Vaughan, Principal Archaeologist
Virgil Weld, Principal Engineer
Persons and Organizations Contacted
City of Dunsmuir
Mike Powers, City Manager
Mike Cascarina, Fire Chief
Dunsmuir Garden Club
Cheryl Petty, Project Manager
Chuck Schlumpberger, P.E.
Tom Hesseldenz and Associates
Tom Hesseldenz, Landscape Architect
Clemens Waste Removal
Jerry Clemens, Owner
Siskiyou County Air Pollution Control District
Eldon Beck, Air Pollution Control Officer
Siskiyou County Sheriff's Department
Matt Rokes, Sergeant
State of California Department of Fish and Game
Bruce Deuel, Wildlife Biologist
Terry Healey, Fisheries Biologist
Rich Lis, Plant Ecologist
Dave Smith, Wildlife Biologist
U.S. Department of the Army
Deborah O'Leary, Regulatory Specialist
©copyright 2001 Dunsmuir Garden Club