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HomeMy WebLinkAboutPN_SPU_BCF_Geotech_Shoreline_Exemption_Narrative_v1 N:\MJA-SPU BCF\Permitting\Geotech Borings\Shoreline Exemption Request Working Document\01 text\SPU BCF_Geotech_Shoreline Exemption Request_2019- 0124.docx Page 1 of 7 To: Jeffrey Taylor, City of Renton Copies: Kay Yesuwan, Seattle Public Utilities Derek Nelson, McMillen Jacobs Associates From: Tessa Gardner-Brown and Ryan Crotty, Floyd|Snider Date: January 28, 2019 Re: Shoreline Permit Exemption Request for Focused Geotechnical Investigation 1.0 Purpose Seattle Public Utilities (SPU) seeks a shoreline letter of exemption to conduct a focused geotechnical investigation (the Proposed Project) to support design for a future upgrade to an existing broodstock collection facility on the Cedar River, within the City of Renton, Washington. The geotechnical investigation will enable SPU to make early design decisions, which will be represented in the future shoreline permit application for development authorization for the future upgrades. The existing broodstock collection facility was constructed to fulfill a mitigation agreement to offset habitat loss for spawning sockeye salmon resulting from the continued operation of the Landsburg Diversion Dam. SPU now intends to upgrade the existing broodstock collection facility to improve its function. This will increase broodstock capture in order to meet prescriptive fish collection quotas established in the mitigation agreement. It will also improve safety by minimizing the level of maintenance required during operation and the significant labor requirements of installation and removal. 2.0 Project Location The site subject to the requested shoreline exemption is located upland of the existing broodstock collection facility, which is on river mile 1.7 of the Cedar River in Renton, Washington, located immediately upstream of the Interstate 405 Bridge (the Project Site). The proposed geotechnical investigations would occur on the north and south side of the Cedar River. Geotechnical investigations on the north side of the Cedar River would occur on parcel 1723059013 (owned by the City of Renton); geotechnical investigations on the south side of the Cedar River would occur on parcel 1723059014 (also owned by the City of Renton), with an easement to SPU for ongoing access to the existing broodstock collection facility. Refer to the Proposed Project’s site plan (Attachment 1) for more details. Jeffrey Taylor, City of Renton January 28, 2019 N:\MJA-SPU BCF\Permitting\Geotech Borings\Shoreline Exemption Request Working Document\01 text\SPU BCF_Geotech_Shoreline Exemption Request_2019- 0124.docx Shoreline Permit Exemption Request for Focused Geotechnical Investigation Page 2 of 7 3.0 Existing Site Conditions 3.1 Land Uses The Project Site encompasses the land immediately to the north and south of the Cedar River, upland of the existing broodstock collection facility. The current land use to the north of the Cedar River includes the City of Renton Community Center. The current land use to the south of the Cedar River includes the Cedar River Trail (located approximately 60 feet to the south of the proposed borings) and a concrete boat ramp/driveway that provides access directly to the Cedar River. Site work for the Proposed Project would not interfere with the normal use of either the Cedar River Trail or the City of Renton Community Center. 3.2 Natural Features and Shoreline Conditions Within the boundaries of the Project Site, the shoreline ecology along the northern bank of the Cedar River at the City of Renton Community Center is limited, consisting primarily of regularly mowed grass. The bank along the north side of the Cedar River has been heavily altered by a retaining wall that extends along the length of the Project Site. The shoreline ecology along the southern bank of the Cedar River is vegetated with medium to dense brush and trees. The southern bank of the Cedar River is mostly natural and gently slopes down to the main channel of the Cedar River. The Project Site does not contain other notable natural features such as wetlands, steep slopes, or water bodies other than the Cedar River. 3.3 Soils According to the U.S. Department of Agriculture (USDA) Web Soil Survey, soils within the Project Site along both the south and north bank of the Cedar River consist of riverwash and urban land. Riverwash is considered a hydric soil. Although riverwash is designated as a hydric soil by the USDA, neither the City of Renton mapping nor the National Wetlands Inventory wetland mapping tool identifies wetlands in the area around the Project Site (Project Area). Urban land is not considered a hydric soil. 4.0 Project Description The Proposed Project consists of collecting three geotechnical borings adjacent to the Cedar River for subsurface investigation. Three borings are expected to be sufficient for the geotechnical investigation; however, if bore logs at these locations are inadequate to determine subsurface conditions, additional boring may be required, not to exceed borings at three additional locations. This geotechnical investigation is required for the assessment of subsurface soil and groundwater conditions that would influence the design of the future upgrades to the existing broodstock collection facility. Refer to Attachment 1 for the approximate locations of the bore holes. Boring would be completed using a hollow stem auger operated by a drill rig, which would bore to depths of approximately 20 to 25 feet below ground surface. As shown on the Jeffrey Taylor, City of Renton January 28, 2019 N:\MJA-SPU BCF\Permitting\Geotech Borings\Shoreline Exemption Request Working Document\01 text\SPU BCF_Geotech_Shoreline Exemption Request_2019- 0124.docx Shoreline Permit Exemption Request for Focused Geotechnical Investigation Page 3 of 7 Proposed Project’s site plan (Attachment 1), bore hole B-101 would occur nearest to the delineated ordinary high water mark (OHWM) of the Cedar River (within approximately 20 feet). The existing pathways will be used largely to mobilize and move equipment, and equipment would not operate within the OHWM at any time. Further, it is not anticipated that vegetation would need to be removed to accommodate the drill rig. However, if vegetation removal is required, it would be limited to only what is necessary and completed using handheld equipment. Tree removal would not occur as a result of the Proposed Project. Once subsurface soil samples have been taken, bore holes B-101 and B-102 would be immediately backfilled and restored to their original condition. However, the third bore hole (B-103) would be temporarily converted to a groundwater monitoring well. Once the groundwater monitoring well is installed and capped, SPU staff would make six monthly site visits to collect groundwater data. After groundwater data collection is complete, the well would be decommissioned in accordance with Washington State Department of Ecology regulations and the land would be restored to its original condition. The geotechnical investigation is proposed to occur in mid-March or early April 2019, or once City of Renton approval has been granted. The geotechnical investigation work is anticipated to take approximately 2 days to complete (not including the groundwater monitoring period). An archaeologist would be on site during soil disturbing activities to ensure the protection of any cultural resources inadvertently discovered during the boring process. Other approvals that would be required before the geotechnical investigations could include a State Environmental Policy Act exemption and permission from the City of Renton to mobilize equipment and conduct geotechnical investigations at the Project Site, because it is within City of Renton ownership. It is anticipated that the cost for the Proposed Project, including all boring, groundwater monitoring, and permitting for the geotechnical investigation, would be approximately $23,000. 5.0 Exemption Type According to Washington Administrative Code (WAC) 173-27-040(2)(m) and Renton Municipal Code (RMC) 4-9-190(C)(12), investigation work within shoreline jurisdiction, which is necessary to support future development applications, is considered exempt from the need to obtain a shoreline permit. Because the Proposed Project includes only investigation activities that are required for the preparation of a future shoreline permit application for upgrades to the existing broodstock collection facility, the geotechnical investigation work would qualify for a shoreline letter of exemption by state law and the locally adopted shoreline master program (SMP). Although the Proposed Project is exempt from the need to obtain a shoreline permit, all shoreline activities, exempt or not, must be consistent with the locally adopted SMP and Shoreline Management Act (SMA). Therefore, a brief consistency analysis between pertinent SMP and SMA regulations and the Proposed Project is provided below. Jeffrey Taylor, City of Renton January 28, 2019 N:\MJA-SPU BCF\Permitting\Geotech Borings\Shoreline Exemption Request Working Document\01 text\SPU BCF_Geotech_Shoreline Exemption Request_2019- 0124.docx Shoreline Permit Exemption Request for Focused Geotechnical Investigation Page 4 of 7 6.0 Consistency with Pertinent Shoreline Management Regulations 6.1 Shoreline Management Act According to the SMA’s specific regulations regarding shoreline exemptions for site investigation work that is necessary to support future development applications, codified under WAC 173-27- 040(m)(i-v) and RMC 4-9-190(C)(12), the following prerequisites must be met for investigation work to be categorized as exempt per SMA standards: i. The activity does not interfere with the normal public use of the surface waters; The proposed geotechnical investigation would not result in the construction of a structure or permanent alteration of land that would preclude the public’s normal use of the Cedar River or the surrounding environment. The geotechnical investigation is anticipated to last approximately 2 days and would be conducted upland of the OHWM of the Cedar River. Due to the short duration of shoreline investigation work and location that the work would take place, the Proposed Project would result in negligible interference to the public’s use of the Cedar River and its associated shoreline environment. ii. The activity will have no significant adverse impact on the environment including but not limited to fish, wildlife, fish or wildlife habitat, water quality, and aesthetic values; The Proposed Project would not have a significant adverse impact to the shoreline ecology. Work would be conducted upland of the OHWM of the Cedar River, which would result in total avoidance of in-water impacts to the Cedar River and the habitat that it provides. The drill rig used for the borings would use existing concrete paths to move, which would avoid and minimize upland shoreline ecology impacts. Although vegetation removal is not anticipated for the Proposed Project, if it is determined to be required once site work begins, it would be completed using handheld equipment. No tree removal would occur. There is no potential for long-term aesthetic impacts because the bore holes would be backfilled and the land restored to its original condition once investigation work is complete. Bore hole B-103 would be temporarily converted to a groundwater monitoring well before being restored to its original condition; however, the aesthetic impact resulting from the temporary groundwater monitoring well would be insignificant based on its small profile (the well would be flush with the ground surface). iii. The activity does not involve the installation of any structure, and upon completion of the activity the vegetation and land configuration of the site are restored to conditions existing before the activity; As stated previously, the Proposed Project would not result in the installation of a structure. Furthermore, any disturbed ground would be restored to its original condition once the investigation activities are complete. Jeffrey Taylor, City of Renton January 28, 2019 N:\MJA-SPU BCF\Permitting\Geotech Borings\Shoreline Exemption Request Working Document\01 text\SPU BCF_Geotech_Shoreline Exemption Request_2019- 0124.docx Shoreline Permit Exemption Request for Focused Geotechnical Investigation Page 5 of 7 iv. A private entity seeking development authorization under this section first posts a performance bond or provides other evidence of financial responsibility to the local jurisdiction to ensure that the site is restored to preexisting conditions; and The applicant is a public agency that has included a plan to restore areas subject to ground disturbance immediately following the conclusion of onsite geotechnical investigation activities. v. The activity is not subject to the permit requirements of RCW 90.58.550; The permit requirements outlined in RCW 90.58.550 pertain to oil or natural gas exploration in marine waters. The Proposed Project is not subject to these requirements. 6.2 City of Renton Shoreline Master Program A consistency analysis between pertinent City of Renton SMP development standards that apply to all activities within the shoreline (RMC 4-3-090(D)), and the Proposed Project is provided below. Environmental Effects The following measures would be taken to ensure that the Proposed Project would result in no net loss of ecological function: 1. The extent of ground disturbance would be kept to the minimum practicable to conduct the geotechnical investigations. The Proposed Project would not require more than six total bore holes to conduct the site investigation work. Ground disturbance would be limited to a hole diameter of approximately 9 inches. No other earthwork is proposed. 2. The Proposed Project is not expected to require the alteration/removal of vegetation along the shoreline. In the instance that vegetation would need to be removed, it would be removed by handheld equipment. Tree removal would not occur. 3. Bore holes would be backfilled with bentonite and restored to their original conditions once the investigation activities are complete. It is anticipated that approximately 1.07 cubic yards of material would be imported to the site in order to backfill and restore the bore holes to their original condition. 4. Ground-disturbing activities would be completed within 2 days of the initiation of site work. The short work window would ensure that local fauna is not exposed to long-term noise impacts, and exposed soils would be restored in a timely manner. In addition to the no-net-loss requirement for any development or activity within shoreline jurisdiction, RMC 4-3-090(D)(2)(c) includes a provision that requires compliance with the City of Renton’s critical areas regulations even if the subject activity is exempt from a shoreline Jeffrey Taylor, City of Renton January 28, 2019 N:\MJA-SPU BCF\Permitting\Geotech Borings\Shoreline Exemption Request Working Document\01 text\SPU BCF_Geotech_Shoreline Exemption Request_2019- 0124.docx Shoreline Permit Exemption Request for Focused Geotechnical Investigation Page 6 of 7 development permit. Because the Proposed Project would occur within the buffer of the Cedar River, compliance with the RMC’s critical areas regulations is required. According to the exempt activities table in the City’s critical areas regulations (RMC 4-3-050(C)), site investigative work necessary for land use application submittals such as surveys, soil logs, percolation tests, and other related activities is considered an activity exempt from the critical areas regulations, provided that the investigative work does not disturb more than 5 percent of the critical area and associated buffer. This regulation also requires impacts to be minimized and disturbed areas to be immediately restored at a one-to-one ratio. The Proposed Project would disturb significantly less than 5 percent of the buffer extending from the Cedar River, and all disturbed areas would be restored to their original condition once the data have been retrieved from the bore holes or groundwater monitoring well. Use Compatibility and Aesthetic Effects The Proposed Project consists of geotechnical investigation work that would influence the design for upgrades to an existing use at the site; therefore, a new use would not directly result from the Proposed Project. Furthermore, the investigation work would not permanently alter the shoreline ecology or require the establishment of a structure. This would ensure that aesthetic qualities in the area would remain consistent with the pre-work conditions at the Project Site. Public Access The Project Site is currently accessible by the public; no changes to permanent public access points would occur. However, during the 2-day investigation work window, the public would be prohibited from accessing the boring sites or interfering with the drill rig/boring equipment. This temporary disturbance to public accessibility within the Project Site would be short term and would not result in an adverse effect on the shoreline’s overall availability for public access. Building and Development Location – Shoreline Orientation The Proposed Project would not directly result in the establishment of a permanent structure or site use; therefore, these standards do not apply. However, the proposed boring locations were chosen partially based on the absence of native vegetation and accessibility for construction equipment. Archaeological, Historical, and Cultural Resources A cultural resources assessment was completed for the Project Area in 2008; no significant cultural or historic resources were identified at that time. Although there are no recorded significant cultural or historic resources within the Project Area, an archaeologist would be on site during ground-disturbing activities to ensure the protection of any resources inadvertently discovered during the boring process. Jeffrey Taylor, City of Renton January 28, 2019 N:\MJA-SPU BCF\Permitting\Geotech Borings\Shoreline Exemption Request Working Document\01 text\SPU BCF_Geotech_Shoreline Exemption Request_2019- 0124.docx Shoreline Permit Exemption Request for Focused Geotechnical Investigation Page 7 of 7 Standards for Density, Setbacks, and Height The Proposed Project would not result in the establishment of a permanent structure or substantial alteration of the Project Site’s natural topography; therefore, these standards do not apply. 7.0 Conclusion As demonstrated in this narrative and the supporting materials that compose the application package, the proposed geotechnical investigation activities are compliant with applicable provisions from the SMA and City of Renton SMP. Therefore, SPU respectfully requests issuance of a shoreline letter of exemption. LIST OF ATTACHMENTS Attachment 1 Proposed Project Site Plan Attachment 1 Proposed Project Site Plan !. !. !<I-405HouserWayNCedarRiverTrail Renton Community Center Cedar R i v e r5050 50 110 50 100 40 5050 90 60 70 80 50 40 60 50 40 30 B-101,25 Feet B-102,20 Feet B-103,20 Feet Document Path: P:\MatLab\Secure\GEOTECH\Geotechnical Projects\SPU\Watershed\Cedar River Watershed\(E114068) Cedar BCF\Preliminary Engineering\Field & Lab Work\Site Maps\Broodstock Site Map.mxdLegendProposed Explorations !.Boring !<Boring w/ Well Existing Broodstock Collection Facility OHWMShoreline Jurisdiction10 Foot Contours2 Foot ContoursParcels Proposed Geotechnical Investigation Site Map Cedar River Hatchery Broodstock Collection Facility Upgrade Renton, Washington FIGURE 2January 2019Project No. E114068 Seattle Public Utilities Geotechnical Engineering 50 0 50 10025 Feet NAVD88-