HomeMy WebLinkAboutSR_ERC_SEPA_Addendum_Apron R_190110.pdfDEPARTMENT OF COMMUNITY
AND ECONOMIC DEVELOPMENT
SR_ERC_SEPA_Addendum_Apron R_180110
ADDENDUM TO ENVIRONMENTAL (SEPA) DETERMINATION OF
NON-SIGNIFICANCE (DNS-M)
Pursuant to WAC 197-11-600(4)(c) and WAC 197-11-625
Addendum to Boeing Apron R Infrastructure Maintenance and Repair
(LUA17-000631, ECF) as Addended by the City of Renton
Determination of Non-Significance - Mitigated (DNS-M)
Date of Addendum: January 14, 2019
Date of Original Issuance of SEPA Threshold Determination: December 18, 2017
Proponent: Mark Clement, The Boeing Company
Project Number: LUA17-000631, ECF, SM, SMC-H
Project Name: Boeing Apron R Infrastructure Maintenance and Repair
Proposal / Purpose of Addendum: The subject property totals 6,677,748 square feet (153.3
acres) and is located in the Commercial Mixed Use Comprehensive Plan (COMP-CMU) land use
designation and Urban Center (UC) zoning classification. The site is currently developed with a
variety of industrial and office buildings related to the manufacturing of 737 airplanes at the
Boeing plant. The northern portion of the site where the work on Apron R will occur is located
within a Regulated Shoreline overlay area. The maintenance and repair work on Apron R will
include concrete replacement and outfall repair within 200 feet of the Lake Washington
shoreline, as well as in-water fill, bulkhead replacement, and riparian habitat installation below
the ordinary high water mark (OHWM). The original threshold determination for the Boeing
Apron R Infrastructure Maintenance and Repair project was issued on December 18, 2017
(Exhibit 2). After the issuance of the original threshold determination, it came to City staffs
attention that the applicant failed to disclose the need for the use of trucks to haul a substantial
amount of fill material. The fill material would be used for both preloading the area of work and
filling in a portion of Lake Washington for the apron expansion per the approved Shoreline
Conditional Use Permit (LUA17-000631).
The intended purpose of this SEPA Addendum is to disclose any proposed changes to the project.
The revised project requires a revision to the approved Shoreline Substantial Development
Permit (LUA17-000631) due to construction that would occur within Reach A of the Cedar River
in the Shoreline High Intensity Designation. In order to allow for construction dump trucks to
more easily access the Boeing plant site near Apron R, the applicant has proposed a temporary
access road embankment at the north end of the construction site across an existing drainage
ditch between Nishiwaki Lane and the project site. Construction of the temporary ditch crossing
SR_ERC_SEPA_Addendum_Apron R_180110
would require the installation of a 12” culvert encased in quarry spall material topped with a
gravel base and approximately 3” of asphalt (see Exhibit 5). A guard shack and rolling security
gate would also be installed on the Boeing plant side of the ditch in order to control access to the
site. The temporary guard shack would include one full-cut off light directed toward the ground
and away from the Cedar River. After project completion, the applicant wou ld remove the
temporary road crossing over the ditch and restore the ditch to its existing, natural state. In
addition, the applicant would be responsible for repaving and restriping approximately 0.5 miles
of Nishiwaki Ln per a future license agreement between the City and the applicant.
Truck hauling for the fill is expected to occur during eight separate construction phases between
January of 2019 and January of 2021. Concentrated high -volume traffic would occur at the start
and end of each phase and may consist of up to 120 trucks per day. Each truck trip would consist
of a fully loaded dump truck with a tandem wheel pup trailer. The proposed truck route (see
Exhibit 3) shows trucks exiting I-405 onto N Southport Dr (turns into Logan Ave N west of Park
Ave N). Trucks would then travel south on Logan Ave N until reaching N 6 th St and would then
turn right and continue straight approximately 1,000 feet until entering into the Cedar River Trail
Park on Nishiwaki Lane. Once on Nishiwaki Ln, trucks would continue traveling north until
reaching the temporary ditch crossing where they would turn right into the Boeing plant site and
dump their loads. Empty trucks leaving the site would follow the same route in reverse in order
to access I-405. The license agreement in-progress between the City and Boeing will include a
number of requirements related to safety that will be implemented such as the presence of
flaggers and spotters, time-of-day haul restrictions, speed restrictions, and various other
precautions.
Pursuant to the City of Renton's Environmental Ordinance and SEPA (RCW 43.21C, 1971 as
amended), on June 10, 2013, the Environmental Review Committee issued a Determination of
Non-Significance (DNS) for Northwest Gourmet. The 14-day appeal period ended on December
28, 2013. No appeals of the threshold determination were filed.
Analysis: It has been determined that the environmental impacts of the proposal were
adequately addressed under the analysis of significant impacts contained within the previously
adopted DNS-M. Based on WAC 197-11-600(4)(c), the addendum process may be used if analysis
or information is added that does not substantially change the analysis of significant impacts and
alternatives in the existing environmental document. The proposed transportation of fill through
the Cedar River Trail Park and removal of vegetation within 200 feet of the Cedar River OHWM is
temporary in nature would is directly related to the approved work for the Apron R
insfrastructure project, which was analyzed as part of the original SEPA theshold determination.
The proposed hauling would not change the original analysis or significantly impact the 1995
State Environmental Policy Act (SEPA) Review.
The City of Renton is hereby issuing a SEPA Addendum pursuant to WAC 197-11-600.
This Addendum is appropriate because it contains only minor information not included in the
original Determination and there are no additional environmental impacts related to inclusion of
the new information.
Location: 737 Logan Ave N, Renton, WA 98055 (APN 1823059254)
SR_ERC_SEPA_Addendum_Apron R_180110
Lead Agency: City of Renton, Department of Community & Economic Development
Review Process: Addendum to previously issued Determination of Non-Significance -
Mitigated (DNS-M)
Additional Information: If you would like additional information, please contact Alex Morganroth,
Associate Planner, City of Renton Planning Division, Department of Community & Economic
Development at (425) 430-7219.
There is no comment period for this Addendum, dated January 10, 2019 issued by the City of
Renton Environmental Review Committee.
Exhibits
Exhibits 1-25: Contained within the original ERC and HEX Documents
Exhibit 26: DNS Addendum
Exhibit 27: Environmental Review Committee Report (LUA17-000631, ECF), dated December 18,
2017
Exhibit 28: Haul Route Map
Exhibit 29: Site Plan
Exhibit 30: Culvert Cross-Section
ENVIRONMENTAL REVIEW COMMITTEE
SIGNATURES:
Gregg Zimmerman, Administrator
Public Works Department
Date
Kelly Beymer, Administrator
Community Services Department
Date
Rick M. Marshall, Administrator
Renton Regional Fire Authority
Date
C.E. “Chip” Vincent, Administrator
Department of Community & Economic Development
Date
DEPARTMENT OF COMMUNITY
AND ECONOMIC DEVELOPMENT
ERC REPORT 17-000631
ENVIRONMENTAL REVIEW COMMITTEE REPORT
ERC MEETING DATE: December 18, 2017
Project Name: Boeing Apron R Infrastructure Maintenance and Repair
Project Number: LUA17-000631, SSDP, CUP-H, ECF
Project Manager: Alex Morganroth, Associate Planner
Owner: The Boeing Company, 737 Logan Ave N, Renton, WA 98055
Applicant/Contact: Mark Clement, PO Box 3707, MC 96-01, Seattle, WA 98124
Project Location: 737 Logan Ave N, Renton, WA 98054
Project Summary: The applicant is requesting a Shoreline Substantial Development Permit, a Hearing
Examiner Shoreline Conditional Use Permit, and an Environmental Threshold
Determination (SEPA) for the proposed maintenance and repair of Apron R. Apron R is
located on northern portion of the Boeing Plant site (Parcel #0723059001) at 737 Logan
Ave N. The northern portion of the site where the proposed work would occur is located
within a Regulated Shoreline overlay area. Further identified as Reach I of Lake
Washington, the upland area has a Shoreline designation of Shoreline High Intensity and
the waterward area to the north has a designation of Aquatic. The 153.30 acre site is
zoned UC - Urban Center and is located in the Commercial Mixed Use land use
designation. The primary function of Apron R is the transportation of completed
airplanes from the Boeing Plant site to the Renton Municipal Airport. The towing of the
airplanes between the assembly line and the air field is a critical function of Apron R,
with an average of 42 airplanes per month utilizing the Apron R transportation corridor.
The aprons secondary function is to provide space for the staging of completed
airplanes when undergoing final checks and inspections. The proposed work on Apron
R would occur within 200 feet of the Lake Washington Shoreline, with additional work
occurring below the ordinary high water mark (OHWM). The proposed work within 200
feet of the shoreline includes the replacement of all concrete on the apron and various
stormwater improvements. The work proposed to occur below the OHWM includes the
conversion of the existing overwater pile-supported section of the apron to fill, a 3,165
sq. ft. water-ward expansion of the apron using in-water fill, construction of a 192 foot
long structural wall to contain the new fill, bulkhead replacement along a large section
of the apron, aquatic habitat enhancement, and riparian plant installation along the
new bulkhead. A Shoreline CUP is required for any excavation or fill below the OHWM.
The total new impervious surface proposed is approximately 3,200 sq. ft. Due to the
scope of the in-water work, the applicant has also submitted a Joint Aquatic Resources
Permit Application to the USACE (Permit #NWS-2017-37), which is currently in review.
The applicant has submitted an Arborist Report, a Technical Information Report, a
Geotechnical Engineering Study, a Standard Lake and Habitat Report, and a Draft
Biological Assessment with the application. Critical areas mapped on the site include a
high seismic hazard, and a habitat conservation area. The applicant has proposed the
removal of five trees and various vegetation on the DNR mitigation site to the north of
the apron as part of a utility removal project. The applicant has also proposed the
removal of non-native and invasive species located near the shoreline along the DNR
property.
City of Renton Department of Community & Economic Development Environmental Review Committee Report
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Report of December 14th, 2017 Page 2 of 15
ERC REPORT 17-000631
Site Area: 6,676,701 SF (153.3 acres)
STAFF
RECOMMENDATION:
Staff Recommends that the Environmental Review Committee issue a Determination
of Non-Significance - Mitigated (DNS-M).
Project Location Map:
PART ONE: PROJECT DESCRIPTION / BACKGROUND
The applicant is requesting Environmental (SEPA) Review for the repair and maintenance of Apron R – a critical piece
of infrastructure on the Boeing plant site. Apron R is located on the south shore of Lake Washington on the Boeing
Plant site. The primary function of Apron R is to provide a corridor for the transportation of Boeing 737 aircraft from
the Boeing Plant site to the Cedar River Bridge which connects the plant to the Renton Municipal Airport. The apron,
approximately 14 acres in size, was originally constructed in the early 1940s and is partially supported by wood piles
driven into the Lake Washington lake bed. Apron R also serves as an area for the staging of aircraft to undergo systems
checks, minor modifications, or the temporarily storage of airplanes prior to transportation to the airport.
Improvements proposed across the entire apron includes concrete replacement and utility trenching in order to
replace existing electrical, compressed air, fire, storm water, and communications utilities. The applicant provided a
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ERC REPORT 17-000631
breakdown of the proposed repair activities based on three distinct parts of the apron: Area 1 – West Apron
Improvements, Area 2 – East Apron Improvements, Area 3 – Central Apron Improvements (see map below).
Area 1 – West Apron Improvements
Improvements on the west portion of the apron would result in approximately 6.3 acres of pavement replacement,
the replacement of pile-supported structures with slab on grade, the replacement of the existing bulkhead, installation
of new storm-water treatment facilities, the installation of aquatic habitat and shoreline function enhancement in
Lake Washington, and the replacement of security fencing between the plant site and the airport. The applicant has
proposed the construction of a new 192-foot long structural wall in Lake Washington that would reclaim
approximately 10,765 sq. ft. of lake. The combined pile-supported apron and west ramp is a structure approximately
11,200 sq. ft. in size. Overwater coverage of the combined structure is approximately 7,600 sq. ft., and during a 2015
inspection, was determined to be supported primarily by untreated timber piling and concrete pile caps. The applicant
has proposed constructing a new structural wall and increasing the size of the current section of apron by
approximately 3,165 sq. ft. As part of the West Apron Improvements, the applicant has also proposed to fill the existing
overwater structure and new section of apron, resulting in a total of 10,765 of new lake fill. The area proposed for fill
contains a “pinch-point” between Building 4-41 and the lake that provides only 130 feet of clearance for the planes
when transported between the plant and the airport. According to the applicant, the extension of the apron further
into the lake represents the smallest possible area that will allow for an airplane bypass route during reconstruction
of the existing west apron. The bypass route is important in order to allow for continuous aircraft production during
the construction project.
Within Area 1, the applicant has also proposed the demolition of the center ramp and west ramp (approximately 7,800
sq. ft. in area), resulting in the removal of approximately 4,200 sq. ft. of overwater coverage. The area of the center
ramp would be converted to nearshore shallow water habitat and the west ramp would be replaced by a structural
wall and the associated fill. According to the studies provided by the applicant, the existing bulkhead wall along the
City of Renton Department of Community & Economic Development Environmental Review Committee Report
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Report of December 14th, 2017 Page 4 of 15
ERC REPORT 17-000631
shoreline of Area 1 has deteriorated and necessitates the replacement of approximately 500 linear feet of wall in order
to support the proposed new pavement on the apron. On the waterward side of the proposed new bulkhead, the
applicant has proposed the creation of a new riparian planting zone and habitat enhancement area that will slope
downwards into the water and significantly improve the ecological function of the shoreline in the project area. In
addition, a location for barges to load/unload materials will be formalized to the east of the existing center ramp by
reducing the amount of aquatic habitat enhancement material in the area of the barge slip and installing steel piles to
prevent barges from making contact with the bulkhead wall.
Area 2 – East Apron Improvements
Improvements on the east apron include the installation of a new stem wall to raise the apron elevation and relocation
of a storm water outfall in the lake. The existing bulkhead wall wraps across approximately 300 feet of the apron
shoreline. The existing inner sheet pile bulkhead that supports Apron R has deteriorated significantly and is in need of
replacement. The new stem wall along the east property line, approximately 263 feet long, would be located
approximately 10 feet landward of the existing inner-pile wall located near the west property line and would not
require any over- or in-water work. The replacement of pavement and utilities are also proposed for the east apron
area.
Area 3 – Central Apron Improvements
The central apron area is located adjacent to the DNR mitigation property. Improvements on the central apron would
be limited to the utility and pavement replacing proposed for the entire apron. Existing utilities would be completely
removed from the DNR mitigation property and relocated into a conduit on the Boeing plant property. The applicant
has proposed the removal of five trees on the DNR property as well as moderate disturbance to vegetation within the
utility easements. Disturbed or removed trees and vegetation would be replaced in order to provide no net loss of
ecological function for the property. Two new storm water outfalls would be installed within easements on the DNR
properties and drain into the lake further water-ward than the existing outfalls. Utility replacement and pavement
replacement, identical to the work to within the east and west apron areas, is proposed for the central apron area.
PART TWO: ENVIRONMENTAL REVIEW
In compliance with RCW 43.21C.240, the following environmental (SEPA) review addresses only those project impacts
that are not adequately addressed under existing development standards and environmental regulations.
A. Environmental Threshold Recommendation
Based on analysis of probable impacts from the proposal, staff recommends that the Responsible Officials:
Issue a DNS-M with a 14-day Appeal Period.
B. Mitigation Measures
1. If any Native American grave(s) or archaeological/cultural resources (Indian artifacts) are found all
construction activity shall stop in accordance with RCW 27.53.060 and 27.44.020, and the
owner/developer shall immediately notify the City of Renton planning department, concerned Tribes’
cultural committees, and the Washington State Department of Archeology and Historic Preservation.
2. The applicant shall submit an Archaeological Monitoring and Inadvertent Discovery Plan MIDP to DAHP
and any interested Tribes for review prior to the start of any ground disturbing activities.
Documentation of the submittal shall be provided to the City of Renton prior to the issuance of building
or construction permits, whichever comes first.
3. The applicant shall comply with the recommendations of the geotechnical report prepared by PanGEO,
dated September 2017, or an updated report submitted at a later date.
City of Renton Department of Community & Economic Development Environmental Review Committee Report
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4. The applicant shall comply with the recommendations of the Standard Lake Study and Habitat Report
prepared by BergerABAM and Amec Foster Wheeler, dated July 17, 2017, or an updated report
submitted at a later date.
5. All construction or restoration work to occur on the DNR property (parcel #0723059105) shall be in
accordance with a mitigation plan approved by the DNR. The approved mitigation plan shall be provided
to and approved by the Current Planning Project Manager prior to construction permit application
submittal.
6. The applicant shall comply with the recommendations included in the Draft Biological Assessment
prepared by BergerABAM and Amec Foster Wheeler, dated June 2017, or an updated report submitted
at a later date.
7. The applicant shall work with the City to relocate the existing easement (Recording #9609040765) to the
location of the original easement (Recording #9209171541) or another location approved by Community
Services Department. The relocated easement shall be recorded prior to Construction Permit issuance.
Alternatively, the applicant could proposed to incorporate the trail design into the mitigation plan and
build the trail in the location of the existing easement as a part of the Apron R construction permits.
8. The applicant shall grant the City a minimum 10-foot wide public trail easement running parallel to the
entirety of the proposed stem wall on the east side of property. The easement shall be reviewed and
approved by the Community Services Department and the City Attorney’s Office. Once approved the
easement shall be recorded prior to construction permit issuance.
C. Exhibits
Exhibit 1 Environmental Review Committee Report
Exhibit 2 Project Narrative
Exhibit 3 Neighborhood Detail Map
Exhibit 4 Construction Drawings (select pages)
Exhibit 5 Environmental Checklist
Exhibit 6 Shoreline Tracking Worksheet
Exhibit 7 Construction Mitigation Description
Exhibit 8 Geotechnical Report prepared by PanGEO Inc (dated September 2017)
Exhibit 9 Standard Lake Study Narrative and Habitat Report prepared by BergerABAM and Amec Foster
Wheeler (dated July 2017)
Exhibit 10 Draft Biological Assessment prepared by BergerABAM and Amec Foster Wheeler (dated June
2017)
Exhibit 11 Technical Information Report prepared by BergerABAM (dated September 2017)
Exhibit 12 Arborist Report prepared by Davey Group (dated November 2017)
Exhibit 13 Department of Archeological and Historic Preservation Comment Letter (dated October 24,
2017)
Exhibit 14 King County Wastewater Treatment Division Comment Letter (dated October 24, 2017)
Exhibit 15 Department of Natural Resources (DNR) Comment Letter (dated October 24, 2017)
Exhibit 16 Department of Transportation (WSDOT) Comment Letter (dated October 26, 2017)
Exhibit 17 Boeing Response Letter to DNR (dated November 20, 2017)
Exhibit 18 Boeing Response Letter to WSDOT (dated November 20, 2017)
Exhibit 19 Department of Natural Resources (DNR) 2nd Comment Letter (dated December 13, 2017)
Exhibit 20 Documents Relating to Sam Chastain Trail
Exhibit 21 Advisory notes to Applicant
City of Renton Department of Community & Economic Development Environmental Review Committee Report
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D. Environmental Impacts
The proposal was circulated and reviewed by various city departments and divisions to determine whether the
applicant has adequately identified and addressed environmental impacts anticipated to occur in conjunction with
the proposed development. Staff reviewers have identified that the proposal is likely to have the following probable
impacts:
1. Earth
Impacts: The subject site is located in an area of a known seismic hazard. As such the applicant submitted a
Geotechnical Report, prepared by PanGEO Inc, dated September 2017 (Exhibit 8). The analysis in the report
primarily focused on the area near the proposed Apron repair project. The recommendations contained
within the geotechnical report relied on the soil characteristics observed during borings used for prior
geotechnical reports prepared for Boeing, as well as new cone penetration tests conducted on the site in
May of 2017.
PanGEO performed eight cone penetration tests (CPT) using a truck-mounted rig. A CPT uses an
instrumented one-inch diameter cone to test for properties such as tip resistance, friction ratio, and pore
pressure. The testing occurred across the Apron R work area at maximum depths ranging from 43 to 57 feet
below grade.
According to the new testing results and data from previous borings, the existing Apron pavement is
generally underlain by 4 to 10 feet of compacted structural fill over approximately 10 to 20 feet of very soft
organic and inorganic silt. The organic silt is generally underlain by loose to medium dense silty sand that
extends to 100-plus feet deep. Groundwater was indicated at about 3 feet below the ground surface in
previous borings and it is anticipate that due to the proximity of the lake, the groundwater level at Apron R
is very similar to the water level in Lake Washington. Levels are also likely to vary seasonally and are heavily
influenced by the water level in the lake.
According to the City of Renton Critical Areas Maps, the project site is located in a seismic hazard area. A
seismic evaluation of the site found a moderate to high potential for liquefaction during a seismic event due
to the presence of ground water and loose silty sand near the project site. Other potential liquefaction-
related hazards are possible without a seismic event include ground settlement and lateral spreading. The
applicant has not proposed any liquefaction mitigation methods.
PanGEO evaluated two types of pavement sections that may be used for the project: New Portland Cement
Concrete surfacing overlying crushed aggregate base course, and New Portland Cement Concrete surfacing
overlying soil-cement treated subgrade. Both options are required to conform to the FAA Advisory Circular
150/5320-6E issued in 2009 – a standard created for all infrastructure associated with commercial aircraft.
The report does not expect the potential load demand on the apron, including front loaders, aircraft, cranes,
or forklifts, to exceed the design loads of either pavement option. If option 1 is selected, the report
recommends that layer of construction geotextile be placed on the subgrade before placement and
compaction of the crushed aggregate. If option 2 is chosen, the report recommends that soil-cement
stabilization be applied to the subgrade soils once grading of the subgrade soils has occurred.
The report specifically evaluates the feasibility of the proposed replacement of the pile-supported apron
near the west ramp. Due to the significant presence of untreated timber piles currently supporting the
existing apron structure, the report recommends driving the majority of the piles below the mudline and
removing select piles that impede installation of the temporary sheet pile wall. After the piles are driven
below the mudline or removed, the fill used to support the new slabs is expected to range from four to eight
feet in depth. The report make recommendations on the appropriate types of backfill to use for both
submerged and above level placement. Additional subgrade stabilization may need to occur if the subgrade
appears soft or easy to disturb during construction.
Due to the presence of compressible soils, PanGEO anticipates immediate ground settlement as well as a
high probability of long-term secondary compression in the area where new in-water fill will be placed. The
City of Renton Department of Community & Economic Development Environmental Review Committee Report
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ERC REPORT 17-000631
report recommends adding several feet of surcharge fill on the area near the west ramp in order to reduce
the anticipated settlement period of the fill. Recommendations for the new 192-foot long bulkhead wall and
rock containment dike to be constructed in order to contain the new fill include overbuilding the
containment dike to accommodate the anticipated settlement, use of clean, well graded crushed rock, using
no greater than a 2H:1V slope.
The existing bulkhead system on the northeast corner of the site in Area 2 is proposed to be raised
approximately 3-4 feet on the landward side of the proposed stem wall. The report recommends that the
existing grades within at least 10 feet of the existing bulkhead wall should not be raised in order to avoid
adding additional pressure against the wall, unless the existing wall can be modified or a new bulkhead wall
is proposed to be built. The applicant has not proposed any modification to the existing bulkhead wall and
should therefore follow the recommendation of the report to raise the ground surface landward of the
existing bulkhead in Area 2
During the installation of the temporary or permanent sheetpiles, the report recommends the contractor
drive one pile at time in order to avoid liquefaction caused by the vibratory hammer. In addition, the
existing timber piles near the northeast corner of the project site should be closely monitored during
sheetpile constructing to ensure the vibratory hammer does not cause any movement.
Temporary excavation and shoring is likely to occur in wet conditions. Construction dewatering will likely be
necessary utility systems replacement. Groundwater collected during the excavations will be discharged into
temporary on-site infiltration trenches. The report recommends excavating the temporary trenches or pits
no more than two feet below the existing grade in order to avoid hitting groundwater. Temporary trenches
should be closely monitored and should be cleaned out regularly to avoid clogs. Infiltration trenches may
also be expanded to avoid potential overflow caused by higher than anticipated discharge rates.
The applicant ha s indicated the project would result in approximately 3,165 sq. ft. of new impervious area
and apprximately 527,000 sq. ft. of replaced impervious surface. Erosion control measures will need to be in
place prior to starting grading actitivies of the site. The report submitted at the time of contruction permit
application should disucss soil and groundwater characteristic in more depth, analyze infiltration potential,
and provide recommendations for project design and contruction.
Mitigation Measures: The applicant shall comply with the recommendations of the geotechnical report
prepared by PanGEO, dated September 2017, or an updated report submitted at a later date.
Nexus: SEPA Environmental Review, RMC 4-4-060 Grading, Excavation and Mining Regulations
2. Air
Impacts: It is anticipated that some temporary air quality impacts could be associated with site work and
building construction required to complete the proposed project at this site. Project development impacts
during construction activities may include dust as a result of concrete replacement, bulkhead installation,
and utility work, as well as exhaust from construction vehicles, equipment and/or machinery. These
emissions would be temporary and are anticipated to rapidly dissipate. Dust control would be mitigated
through the use of temporary erosion control measures, watering or other best management practices as
identified in the construction mitigation memo provided by the applicant (see Exhibit 7).
No further site specific mitigation is recommended for the identified impacts from typical vehicle and
construction exhaust.
Mitigation Measures: No further mitigation recommended.
Nexus: N/A
3. Water
a. Wetlands, Streams, Lakes
City of Renton Department of Community & Economic Development Environmental Review Committee Report
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Impacts: The project site is located along Lake Washington, a Shoreline of the State. The southern portion of
Lake Washington adjacent to the project site is designated High Intensity by the Shoreline Master Program.
The outflow of Lake Washington is the Lake Washington Ship Canal. Lake Washington has been altered
significantly over the past century and the development along the shoreline has contributed to loss of habitat
primarily due to new overwater structures, removal of riparian vegetation and large woody debris, and an
increase in shoreline armoring. Due to the majority of the proposed improvements being located within 200
feet of the Lake Washington OHWM and waterward of the OHWM, the applicant submitted a combination
Standard Lake Study Narrative and a Habitat Data Report, prepared by AMEC Foster Wheeler and dated July
2017. According to the study, no wetlands or streams were noted within the immediate vicinity of the project
area. Although not noted in the reports, the site is approximately x feet from the Cedar River a stream of sate
wide significant. The Standard Lake Study Narrative is provided under a separate section of the report and
includes information on the existing habitat conditions and functions of Lake Washington adjacent to the
proposed project site.
According to the report, approximately 1,500 of the 2,600 linear feet of the Lake Washington shoreline along
the project area consists of pile-supported concrete deck, concrete bulkhead, sheet-pile bulkhead, and riprap
armoring. The remaining 1,100 feet linear of shoreline is occupied by a DNR shoreline habitat restoration area.
The restoration area was constructed between 2013 and 2015 as part of required mitigation for the SR 520
floating bridge project. The report provides summaries of the potential impacts on the water and habitat in
addition to mitigation measures proposed to help offset the loss of aquatic resources due to the project.
In order to offset the loss of aquatic resources and lessen the impact of the proposed project, the applicant
has proposed multiple mitigation measures adjacent to Apron R that would be implemented after the
construction work is completed. The proposed mitigation is primarily designed to improve the nearshore
aquatic habitat for juvenile salmonids along the south Lake Washington. The mitigation would be comprised
of three elements: the installation of multiple fills to prevent undermining and to enhance the benthic habitat,
the installation of multi-level fill slopes, and the installation of riparian plantings to improve the ecological
function of the shoreline (see Exhibit 2).
The goal of the first two elements, using multi-level fill slopes to support the multi-sloped benthic
environment, would reduce wind/wave erosion in the new shoreline area while providing an improved, fish-
friendly habitat for juvenile salmonids. This would be accomplished by installing loose riprap on the lakebed
that would slope towards the water and away from the bulkhead and provide support for the benthic
environment. On top of the mechanically-compacted riprap, a 2-foot thick habitat mix would provide a
significantly improved environment for fish and other aquatic wildlife. Lastly, the enhancement plan would
create a new near shore environment averaging 10 feet in width as measured waterward from the edge or
the apron. The proposed shoreline would extend approximately 1 foot above the OHWM in order to create
an area suitable for the planting of new riparian plant species. The addition of the new riparian planting zone
would improve shoreline function by providing shade during the day, blocking artificial light sources at night,
and increasing organic matter put into the lake.
The primary focus of the report is to evaluate the proposed habitat mitigation measures in order to preserve
and enhance riparian and shallow-water habitats for juvenile salmonids in Lake Washington. Mitigation
measures proposed include the removal of invasive plant species and replacement with native riparian
vegetation, the removal of shoreline armoring and the center ramp structure, and the creation of nearshore
shallow-water habitat and riparian buffer. The study concludes with the installation and completion of the
identified mitigation the proposed lake fill and other site changes would be mitigated and result in no net loss
of ecological functions and values. Based on the recommendations included in the study, staff recommends
as a mitigation measures that the applicant comply with the recommendations included in the Lake Study.
Mitigation Measures:
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1. The applicant shall comply with the recommendations of the Standard Lake Study and Habitat Report
prepared by BergerABAM and Amec Foster Wheeler, dated July 17, 2017, or an updated report
submitted at a later date.
2. All construction or restoration work to occur on the DNR property (parcel #0723059105) shall be in
accordance with a mitigation plan approved by the DNR. The approved mitigation plan shall be provided
to and approved by the Current Planning Project Manager prior to construction permit application
submittal.
Nexus: SEPA Environmental Review, RMC 4-3-090 Shoreline Master Program Regulations
b. Storm Water
Impacts: The applicant submitted a Technical Information Report (TIR) prepared by DOWL, dated May 2017,
and revised the study May 2017 (see Exhibit 13). Based on the updated TIR, the project contains greater than
2,000 SF of replaced impervious surface and therefore Full Drainage Review is required and the development
is subject to the 2017 City of Renton Surface Water Design Manual (RSWDW). Based on the City’s flow control
map, this site falls within the Peak Rate Flow Control Standard matching Existing Site Conditions. A Full
Drainage Review was included in the report.
The project site is located within the Lake Washington and Cedar River Drainage basins. The flow-path from
the project site discharge point is less than 0.5 miles from the 100-year floodplain of Lake Washington and
therefore qualifies for the direct discharge exemption in accordance with Section 1.2.3.1 of the RSWDW and
must adhere to all requirements thereof.
The area of the site improvements discharge into two separate threshold discharge areas that converge
more than ¼ mile downstream. The project is classified as a redevelopment project in accordance with
RSWDM. As a redevelopment project, the improvements are exempt from Core Requirement #8, Water
Quality. Therefore, the development is exempt from the requirement to provide water quality treatment
prior to discharge for each separate threshold discharge area. However, the applicant has elected to provide
enhance water quality treatment prior to discharge in order to provide a benefit to Lake Washington and its
aquatic habitat. Water quality treatment will consist of conveyance to oil/water separator vaults, which will
direct surface water to several Linear Modular Wetland systems prior to discharge to the outfalls in Lake
Washington.
On-site BMPs will be required to help mitigate the new runoff created by the proposed improvements. The
final drainage report submitted at the time of construction permit application should address the
implementation of on-site BMPs. This includes analyzing the feasibility of basic dispersion for the target
impervious surface areas that may be able to disperse into added or existing landscaped areas.
A Stormwater Pollution Prevention Plan (SWPPP) is required for this site and the final drainage plan and
drainage report must be submitted with the utility construction permit application. A Construction
Stormwater General Permit from the Department of Ecology is required if grading and clearing of the site
exceeds one acre.
It is anticipated that the City’s current adopted 2017 City of Renton Surface Water Design Manual would
adequately mitigate any impacts that could result from the proposed development; therefore no further
mitigation is recommended.
Mitigation Measures: No further mitigation required.
Nexus: No applicable
4. Trees and Vegetation
Impacts: The project site is primarily comprised of impervious, non-vegetated surface. A habitat survey of the
site was conducted in order to assess the conditions and vegetative cover along the entire length (~2,600
City of Renton Department of Community & Economic Development Environmental Review Committee Report
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Report of December 14th, 2017 Page 10 of 15
ERC REPORT 17-000631
linear feet) of the proposed Apron R project site. Approximately 1,500 feet of the 2,600 linear feet of the area
along the north boundary of the site is comprised of pile-supported concreted deck, concrete bulkheads, or
riprap sections. The remaining 1,100 linear feet of shoreline is occupied by a DNR shoreline habitat restoration
area established as part of the SR 520 Bridge Replacement project. Aside from the DNR shoreline property
adjacent to the area of work, riparian vegetation along the shoreline adjacent to the site is generally sparse
and consists primarily of invasive, non-native species such as Himalayan blackberry, Japanese knotweed, and
English ivy. Removal of the invasive species is proposed as a part of the project and would be replanted with
native species.
The WSDNR property contains a fifteen (15) foot wide easement along the apron granted to Boeing for
electrical, water, and mechanical utilities. The majority of the DNR property, including the area around
Boeing’s existing utility easement, is planted with trees and other native species as part of a WSDOT mitigation
project required for the SR 520 Bridge Replacement completed in 2016. Boeing has been working with WSDNR
on a plan to remove the utilities and relinquish the easement since 2016. As part of the Apron R project,
Boeing agreed to relocate the utility lines onto Boeing property and install the lines in a buried conduit under
the apron pavement.
In the originally submitted Environmental Checklist and various studies, the applicant did not address the
potential impacts to the vegetation and trees on the DNR property (Parcel #0723059105) that could result
from the utility removal. Both WSDOT and the DNR both submitted comment letters requesting additional
information on the potential impacts of the proposed work (see Exhibit 15 and 16). Boeing resubmitted an
amended Environmental Checklist, Standard Lake Study and Habitat Data Report, and Arborist Report (all
included as exhibits of this report) that included additional information on the impacts to trees and vegetation
on the DNR property. Boeing also included official response letters to each agency that addressed the issues
raised by the agencies during their first-round reviews. The City provided the response letters and new studies
to WSDOT and DNR. The DNR provided a letter dated December 13, 2017 stating that Boeing’s response to
the initial comment letter sufficiently addressed the agency’s concerns regarding restoration of the DNR
property (see Exhibit 19). In addition, staff was informed on December 7, 2017 that Boeing, the DNR, and
WSDOT will meet within the next few weeks to discuss the technical aspects of restoring the mitigation area
on the DNR site after utility removal. The applicant has worked with DNR and WSDOT over the past few
months to determine the more effective and least disruptive method to remove the utilities without
negatively impacting the mitigation area. However, the parties have not been able to come to an agreement
on the exact scope of work. After a mitigation plan is approved by the DNR, the applicant or DNR should
provide copy of the plan to the city to ensure compliance with the Shoreline Master Program regulations or
other approved plans.
According the updated Standard Lake Study and Habitat Data Report and Arborist Report, the excavation of
the utilities and expansion of the paved apron areas into critical root zones will necessitate both the removal
and pruning of various trees on the DNR site. According the updated Arborist Report prepared by the Davey
Group, the site has a total of 57 trees, 29 of which are classified as significant trees per City of Renton
classifications (see Exhibit 12). Five trees have been identified for removal including the species bigleaf maple,
Cascara buckthorn, vine maple, Scouler’s willow, and black cottonwood (see Exhibit 9, Figure 1). None of the
trees proposed for removal are classified as landmark trees (under 30” DBH) and only two are classified as
significant trees (over 6” DBH). In addition to the trees proposed for removal, another 37 trees have been
identified for crown-raise pruning. Crown pruning removes the lower limbs of the tree and would reduce the
likelihood of conflict and mechanical damage to tree limbs. According to the Arborist Report, crown-raising
does not permanently damage the tree and will significantly increase the chance of the tree’s survival during
the construction process.
After the utilities are removed, the excavated material would be replaced and restored to its previous
condition. In order to compensate for the disturbance, plant species matching existing conditions would be
replanted at a higher density and size than what is currently on the site. In addition, removed trees would be
replaced at a 1:1 ratio. The replacement trees will be installed slightly further water-ward in order to ensure
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Report of December 14th, 2017 Page 11 of 15
ERC REPORT 17-000631
they are replanted outside of the wing-tip clearance zone. Tree protection fencing will be installed around
the retained trees prior to the start of construction activities and would coincide with the critical root zones
areas identified for each tree.
Based on the recommendations included in the Stream Study, Habitat Report and Arborist Report, staff
recommends as mitigation measures that the applicant comply with the recommendations included in these
studies including but not limited to re-vegetation of the DNR property and tree replacement at 1:1 ratio.
Above under “Water” staff has already added a mitigation measure to comply with the stream study.
Mitigation Measures:
1. The applicant shall comply with the recommendations included in the Standard Lake Study and Habitat
Report prepared BergerABAM and Amec Foster Wheeler, dated July 17, 2017.
2. The applicant shall comply with the recommendations of the Arborists Report prepared by the Davey
Group, dated November 2017, or an updated report submitted at a later date.
3. All construction or restoration work to occur on the DNR property (Parcel #0723059105) shall be in
accordance with a mitigation plan approved by the DNR. The mitigation plan shall be provided to the
Current Planning Project Manager prior to construction permit application submittal in order to review
for compliance with City of Renton’s Tree Retention and Land Clearing Regulations in section RMC 4-4-
130.
Nexus: SEPA Environmental Review, RMC 4-3-090 Shoreline Master Program Regulations, RMC 4-4-130 Tree
Retention and Land Clearing Regulation”.
5. Wildlife
Impacts: The project is located in an area of threatened species under the Endangered Species Act, the
Puget Sound Chinook salmon and Puget Sound steelhead trout. In addition to the two threatened species
WDFW Wildlife’s Priority Habitat and Species database identified five salmonid species that use the lower
Cedar River, Chinook salmon, Coho salmon, Sockeye salmon, Steelhead, rainbow trout, and Coastal
cutthroat trout. The study also identified the potential presence of bull trout in the upper Cedar River
watershed. However, due to extremely limited reports of bull trout in the past few decades, the occurrence
of bull trout in Lake Washington adjacent to the project site is expected to be minimal. The provided Lake
Study and Habitat Report includes a wildlife analysis for area near the Lake Washington and the Cedar River
in the project site vicinity (see Exhibit 9). The entire project area is highly developed and disturbed due to
the presence of the Boeing plant site. The report concludes that with the exception of the WSDNR site, the
shoreline area near the project site provides very low habitat value and function due to the sparse riparian
vegetation and extensive development along the shoreline of both Lake Washington and the Cedar River.
Within the DNR site shoreline area, biologists observed several bird species including the American crow,
gulls, and European starlines. No mammals were observed near the project site but are likely to be present.
Given the level of development in the project area, it is likely that only small mammals such as squirrels,
mice, rats, etc, use the riparian areas along the lower Cedar River and Lake Washington shoreline within 100
feet of the project area. In addition, no amphibians or reptiles were observed during the site visits, but
many species are found in the Lake Washington basin and are likely present within the site vicinity. The
report concludes that impacts to land-based animals is expected to be minimal and temporary in nature.
As part of the Apron R rehabilitation project, significant in-water work will occur below the OHWM. In-water
work will include bulkhead replacement, construction of new structural wall, conversion of a 7,600 sq. ft.
overwater coverage to fill, demolition of the existing center ramp, and aquatic habitat enhancement. The
only portion of the project that could potentially affect aquatic biota is light impingement from the
additional lighting proposed for the Apron project. In order to mitigate light impingement from the new and
City of Renton Department of Community & Economic Development Environmental Review Committee Report
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Report of December 14th, 2017 Page 12 of 15
ERC REPORT 17-000631
existing light sources, riparian vegetation will be planted along the entire span of the bulkhead in order to
shield the near-shore area during nighttime hours.
In order to reduce the impact of the in-water work on the wildlife and habitat near the project site, the work
would be completed over three construction seasons. In-water work windows are designated in order to
protect species and their habitats and are assigned during times when there is less likelihood of disturbance.
Due to the scope of the work to be completed below the OHWM, Boeing has requested extensions for the
in-water work windows either on the back or front end of the standard work windows. The agencies with
authority to grant the extension include the National Oceanic and Atmospheric Administration, National
Marine Fisheries Service, and the U.S. Fish and Wildlife Service, and will make a determination as part of the
JARPA permit decision. Additional impacts to wildlife are identified in Section 7(a) Noise below.
The Draft Biological Study prepared by Amec Foster Wheeler concludes that short-term impacts to the three
salmonid species in the Lake Washington basin may including increased turbidity causing a decrease in
water quality, temporary obstructions from machinery, and a change in behavior responses from juvenile
salmonids due the noise caused by pile driving and use of a vibratory hammer (see Exhibit 9). The report
identifies twenty (20) best management practices recommended for implementation in order to mitigate for
the impacts to fish and other wildlife during construction. The study finds that the proposed project has the
potential to affect the species identified within the project area (see Exhibit 9). The study concludes that
project does not have the potential to adversely affect the Puget Sound Chinook Salmon or Puget Sound
Steelhead Trout in the long term and will instead benefit the two species due to the coinciding shoreline
habitat restoration that is part of the project. In addition, the project concludes that the proposed project
will provide minimal, if any, long-term beneficial or adverse effects to Coastal/Puget Sound bull trout.
Mitigation Measures:
1. The applicant shall comply with the recommendations included in the Standard Lake Study and Habitat
Report prepared BergerABAM and Amec Foster Wheeler, dated July 17, 2017.
2. The applicant shall comply with the recommendations included in the Draft Biological Assessment
prepared by BergerABAM and Amec Foster Wheeler, dated June 2017.
Nexus: SEPA Environmental Review, RMC 4-3-090 Shoreline Master Program Regulations
6. Energy and Natural Resources
Impacts: The types of energy likely to be used to implement the proposed project include gas-powered and
diesel-powered vehicles and machinery. The use of these vehicles would be temporary. The completed
project is not expected to require any energy.
Mitigation Measures: No further mitigation recommended.
Nexus: N/A
7. Environmental Health
a. Noise
Impacts: Noise and vibration impacts would primarily result from removal of the existing piles and the
driving of the steel sheet pile wall installed against the existing timber sheet pile wall. The equipment noise
would be regulated through the City’s adopted noise level regulations per Chapter 8-7, RMC. The City’s noise
regulations limit haul hours between 8:30 am to 3:30 pm, Monday through Friday unless otherwise
approved by the Development Services Division. Work on Saturdays is restricted to the hours between 9:00
a.m. and 8:00 p.m. No work is permitted on Sundays.
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Generally, noise impacts would come from the operation of the heavy construction equipment that would
generate expected noise levels of up to 94 decibels. Underwater noise from vibratory extraction and driving
of piles would be greater than that of other construction equipment. Underwater noise generated from the
vibratory pile driving would be expected to be less than 150 decibels. The applicant indicates that all the
construction noise impacts are anticipated to occur during normal daytime working hours and may occur on
nights and/or weekends in order to complete the project within the restricted fish window (no in-water
construction from January 1st through July 15th and August 1st through November 15th). The short 45-day
construction window dictates the impacts would be temporary. If noise levels exceed maximum permissible
levels as outlined in RMC 8-7, a noise variance would be required. A request for a noise variance lasting
longer than two (2) days would require a public hearing and would be publicly noticed.
Noise impacts are anticipated to be short-term impacts that would be completed within the approved fish
windows. Additional staff analysis on noise impacts can be found under section “Wildflie”.
Mitigation Measures: No further mitigation recommended.
Nexus: N/A
8. Historic and Cultural Preservation
Impacts: The SEPA checklist submitted by the applicant indicated that they completed a search of the
Washington State Information System of Architectural and Archaeological Records Data. The Checklist
concludes that the system did not identify any properties within the project area as being on the historic
property inventory or register. A letter received from the State Historic Preservation Officer on behalf of the
Department of Archaeology and Historic Preservation (DAHP), dated October 24, 2017 (see Exhibit 13 ),
contained analysis and a recommendation related to the proposed improvements.
There are two precontact archaeological sites recorded within 3,000 feet of the project area, as well as
precontact trail systems. The presence of these sites and trails indicates that there is a high probability that
the project site contains various precontact archaeological resources. As such, staff recommends as a
mitigation measure that if any Native American grave(s) or archaeological/cultural resources (Indian
artifacts) are found all construction activity shall stop in accordance with RCW 27.53.060 and 27.44.020, and
the owner/developer shall immediately notify the City of Renton planning department, concerned Tribes’
cultural committees, and the Washington State Department of Archeology and Historic Preservation. The
SEPA check list indicates that if any archaeological resources are encountered a professional Archaeologist
would be called to assess the significance of the find.
Due to parts of the proposed project that would occur under the existing impervious surface, DAHP has
recommended that the applicant hire a professional archeologist to monitor ground disturbing activities. In
addition, DAHP recommended the applicant prepare an archaeological monitoring and inadvertent
discovery plan (MIDP) to be submitted to DAHP and the interested Tribes for review prior to any ground
disturbance.
Mitigation Measures:
1) If any Native American grave(s) or archaeological/cultural resources (Indian artifacts) are found all
construction activity shall stop in accordance with RCW 27.53.060 and 27.44.020, and the
owner/developer shall immediately notify the City of Renton planning department, concerned Tribes’
cultural committees, and the Washington State Department of Archeology and Historic Preservation.
2) The applicant shall submit an Archaeological Monitoring and Inadvertent Discovery Plan MIDP to DAHP
and any interested Tribes for review prior to the start of any ground disturbing activities.
Documentation of the submittal shall be provided to the City of Renton prior to the issuance of building
or construction permits.
Nexus: SEPA Environmental Review, RCW 27.53 Archaeological Sites and Resources, and RCW 27.44 Indian
Graves and Records
City of Renton Department of Community & Economic Development Environmental Review Committee Report
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ERC REPORT 17-000631
9. Recreation and Public Access
Impacts: The Sam Chastain Trail is a regional, multiuse trail that circumnavigates Lake Washington. The trail
is completely built out except for a small segment in Renton planned to extend along the Lake Washington
shoreline near the Boeing Plant. The unfinished trail segment lies between the Hyatt Regency Hotel on the
adjacent parcel to the east of the Boeing Plant site and the Cedar River Trail Park to the west of the Boeing
Plant (see Exhibit 20). The planned route for the unfinished segment includes an overwater trail stretching
between the Renton Rowing Club dock and the DNR property, then over land on the DNR property,
extending across the northeast corner of Boeing Apron R, to where it connects to the easements on the
Hyatt Regency site. In order to construct the trail across the section of Boeing property that extends into the
lake, the City of Renton obtained an easement from Boeing in 1992 for a nearly 30-foot wide trail connecting
the Rowing Club Dock with the DNR property. In 1996, the two parties amended agreement and relocated
the easement so as to remain over water but to shift the location to a route directly adjacent to the
bulkhead associated with Apron R (see Exhibit 20).
In order to mitigate for the approximate 11,000 sq. ft. of lake fill proposed as part of the expansion of Apron
R, the applicant has proposed mitigation along the Apron R bulkhead in Area 1. Mitigation proposed
includes the addition of a sloped fish habitat enhancement area and a 10 foot wide riparian habitat zone
adjacent to the Apron R bulkhead. As proposed, the mitigation would be located within the existing trail
easement and would impede the ability of the City to exercise its right to construct the last remaining
section of the Sam Chastain Trail. In order to ensure that the City retains the ability to construct this critical
linkage, staff recommends as a mitigation measure that the applicant agree to relocate the overwater
easement to the original location as depicted in the King County Record #9209171541 (see Exhibit 20) which
would move the trail outside the proposed mitigation site.
The proposed construction of a stem wall in Area 2 on the east side of the property would also impact the
City’s ability to make the trail connection and provide recreational access to Lake Washington via the Sam
Chastain Trail. Proposed construction in Area 2 includes the raising of the northeast corner of the apron in
order to direct surface water to new a stormwater conveyance system. The proposed grade change and
associated retaining/stem wall would impact access to the shoreline and could impede public access to Lake
Washington as required by the Shoreline Master Program Regulations in RMC 4-3-090. In order to preserve
public access to Lake Washington and the opportunity to complete a planned regional trail connection, staff
recommends as a mitigation measure that the applicant grant the city a 10-foot access easement between
the proposed new stemwall and east property line.
Mitigation Measures:
1) The applicant shall work with the City to relocate the existing easement (Recording #9609040765) to the
location of the original easement (Recording #9209171541) or another location approved by Community
Services Department. The relocated easement shall be recorded prior to Construction Permit issuance.
Alternatively, the applicant could proposed to incorporate the trail design into the mitigation plan and
build the trail in the location of the existing easement as a part of the Apron R construction permits.
2) The applicant shall grant the City a minimum 10-foot wide public trail easement running parallel to the
entirety of the proposed stem wall on the east side of property. The easement shall be reviewed and
approved by the Community Services Department and the City Attorney’s Office. Once approved the
easement shall be recorded prior to construction permit issuance.
Nexus: SEPA Environmental Review, RMC 4-3-090 Shoreline Master Program Regulations, Trails and Bicycle
Master Plan, Chastain Waterfront Trail Plan.
E. Comments of Reviewing Departments
The proposal has been circulated to City Department and Division Reviewers. Where applicable, their comments
have been incorporated into the text of this report and/or listed under Exhibit 21 “Plan Review Comments to
Applicant.”
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ERC REPORT 17-000631
Copies of all Review Comments are contained in the Official File and may be attached to this report.
The Environmental Determination decision will become final if the decision is not appealed within the 14-day
appeal period (RCW 43.21.C.075(3); WAC 197-11-680).
Environmental Determination Appeal Process: Appeals of the environmental determination must be filed in writing
together with the required fee to: Hearing Examiner, City of Renton, 1055 South Grady Way, Renton, WA 98057, on
or before 5:00 p.m. on January 5, 2017. RMC 4-8-110 governs appeals to the Hearing Examiner and additional
information regarding the appeal process may be obtained from the City Clerk’s Office, Renton City Hall – 7th Floor,
(425) 430-6510.
Goals:
- Left turns only at major intersections
for pedestrian safety.
- No staging area.
Proposed
Ingress and
Egress Route
Page 43 - Trucking Route
Page 42 of 61
Page 42 - Trucking Route
38'-6"
60'-0"
Security Guard
Shack. Power to
be provided.
Rolling Security
Gate Closed
Position
Existing CB Rim
(ELV-99.75')
10'-0"
POC 10' South of
existing MH
75' - 12" DI STS Culvert
Insert
1:2 Slope
max
1:2 Slope max
POT
Relocate
PEDESTRAIN Xing
Sign & Bollards
New stripe
TBM EL 100.0' (Valve Access Rim)
ELV-99.94'
ELV-99.95'
ELV-98.36'ELV-98.36'ELV-98.37 ELV-98.36'ELV-98.33'ELV-98.36'
ELV-98.35'
ELV-98.33'
ELV-99.35'ELV-99.62'ELV-99.81'
ELV-99.82'
ELV-99.85'
ELV-99.87'ELV-99.84'
ELV-99.80'
ELV-99.92'
ELV-99.35'
ELV-99.91
ELV-100.07'
Existing CB Rim
(ELV-99.83')
ELV-97.03'INV ELV-97.04'INV ELV-97.18'
INV ELV-97.24'INV ELV-97.99'INV ELV-97.03'
Gate Work Plan
Rock and
asphalt
infill
Gate Fence
Post
Gate Fence
Post
Rolling Security
Gate Open
Position
Space
allocated for
two Boeing
Security
Parking Stalls
Remove
current
motorcycle
parking
33'18'
Space
allocated for
motorcycle
parking
Page 40 – Temporary Construction Entrance Design
Page 40 of 61
Page 41 - PBS Engineering – Preliminary Culvert Design
Page 41 of 61