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HomeMy WebLinkAboutECF_SEPA_Checklist_250131_v1SEPA Environmental checklist September 2023 Page 1
(WAC 197-11-960)
SEPA1 Environmental Checklist
Purpose of checklist
Governmental agencies use this checklist to help determine whether the environmental impacts of your
proposal are significant. This information is also helpful to determine if available avoidance, minimization, or
compensatory mitigation measures will address the prob able significant impacts or if an environmental impact
statement will be prepared to further analyze the proposal.
Instructions for applicants
This environmental checklist asks you to describe some basic information about your proposal. Please answer
each question accurately and carefully, to the best of your knowledge. You may need to consult with an
agency specialist or private consultant for some questions. You may use “not applicable” or “does not apply”
only when you can explain why it does not apply and not when the answer is unknown. You may also attach
or incorporate by reference additional studies reports. Complete and accurate answers to these questions
often avoid delays with the SEPA process as well as later in the decision-making process.
The checklist questions apply to all parts of your proposal, even if you plan to do them over a period of time
or on different parcels of land. Attach any additional information that will help describe your proposal or its
environmental effects. The agency to which you submit this checklist may ask you to explain your answers or
provide additional information reasonably related to determining if there may be significant adverse impact.
Instructions for lead agencies
Please adjust the format of this template as needed. Additional information may be necessary to evaluate the
existing environment, all interrelated aspects of the proposal and an analysis of adverse impacts. The checklist
is considered the first but not necessarily the only source of information needed to make an adequate
threshold determination. Once a threshold determination is made, the lead agency is responsible for the
completeness and accuracy of the checklist and other supporting documents.
Use of checklist for nonproject proposals
For nonproject proposals (such as ordinances, regulations, plans and programs), complete the applicable parts
of sections A and B, plus the Supplemental Sheet for Nonproject Actions (Part D). Please completely answer all
questions that apply and note that the words "project," "applicant," and "property or site" should be read as
"proposal," "proponent," and "affected geographic area," respectively. The lead agency may exclude (for non -
projects) questions in “Part B: Environmental Elements” that do not contribute meaningfully to the analysis of
the proposal.
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SEPA Environmental checklist September 2023 Page 2
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A. Background
Find help answering background questions2
1. Name of proposed project, if applicable:
Longacres Campus Master Plan
2. Name of applicant:
Unico Longacres Commercial East LLC, Unico Longacres Commercial South LLC, Unico
Longacres Residential SW LLC, Unico Longacres Residential NW LLC
3. Address and phone number of applicant and contact person:
Unico Properties
1326 5th Ave, Suite 800 Seattle WA 98101
Julia Reeve juliar@unicoprop.com
Shaun Duigan shaund@unicoprop.com
4. Date checklist prepared:
January 31, 2025. Master Site Plan Application
5. Agency requesting checklist:
City of Renton WA
6. Proposed timing of schedule (including phasing, if applicable):
The proposed schedule is to start Early Works for construction in Q4 of 2025. The Master
Plan has three phases over a 10-15 year duration.
7. Do you have any plans for future additions, expansion, or further activity related to or
connected with this proposal? If yes, explain.
Not currently.
8. List any environmental information you know about that has been prepared, or will be
prepared, directly related to this proposal.
Following Items were prepared for the Longacres Campus Master Plan Application
Alta Survey by NV5
Arborist Report by Salish Restoration Associates
Critical Areas Report by Pace Engineers
Drainage Report and Drainage Control Plan by Coughlin Porter Lundeen
Geotechnical Report by Geoengineers
Transportation and Parking Memo by TenW
Previous environmental Review for Longacres Site
SEPA application for Sounders FC Center at Longacres (December 2022)
Draft Environmental Impact Statement, Longacres Office Park (August, 1994)
Final Environmental Impact Statement, LOP (March, 1995)
LOP Environmental Impact Statement, LOP (March, 1995)
Environmental Checklist (December, 1996) and MDNS (January, 1997). Boeing BCAG
Headquarters Building
2 https://ecology.wa.gov/Regulations-Permits/SEPA/Environmental-review/SEPA-guidance/SEPA-checklist-
guidance/SEPA-Checklist-Section-A-Background
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(WAC 197-11-960)
Environmental Checklist (September, 1997) and MDNS (November, 1997), Boeing
Family Care Center
Environmental Checklist and MDNS (September, 1998) Boeing Surface Water
Management Project
Environmental Checklist for Development Agreement (2000)
Environmental Checklist for development of lots 27-31 in Longacres (2015)
9. Do you know whether applications are pending for governmental approvals of other
proposals directly affecting the property covered by your proposal? If yes, explain.
No other applications are pending at this time at the Longacres Campus. The Sounders FC
Center at Longacres completed a Conditional Use Permit and SEPA review in December
2022.
10. List any government approvals or permits that will be needed for your proposal, if known.
City of Renton Master Site Plan (Hearing Examiner), Planned Urban Development,
Development Agreement, Final Lot Boundary Adjustment.
11. Give brief, complete description of your proposal, including the proposed uses and the
size of the project and site. There are several questions later in this checklist that ask you
to describe certain aspects of your proposal. You do not need to repeat th ose answers on
this page. (Lead agencies may modify this form to include additional specific information
on project description.)
Longacres has been an important place in the history of the Puget Sound region for the
better part of the Century. Unico’s vision for the site is to continue and build upon that
legacy with an innovative and forward-looking Master Plan that would be implemented
over the next 10 years. The intent is to create a unique and vibrant mixed -use development
in Renton.
Currently there is +/- 330,000 SF of existing commercial office space (CO-Commercial Office)
on the site and existing maintenance and utility buildings (IM- Industrial Medium). The
Seattle Sounders FC Performance Center at Longacres (under separate Permit) is also a part
of the Longacres Campus occupying approximately 13 acres to the West of Office Building
25-20. The Master Plan would add approximately 3,000 new residential units,
approximately 1,400,000 sf of additional commercial office space, additional Light industrial
space, Medical Office Building, a music venue, hotels and Retail, Parking, Roadways and
Infrastructure.
In addition to the above proposed uses, Longacres includes substantial natural resources
that will be enhanced and expanded to serve as amenities to tenants and visitors of the
campus. These natural resources provide habitat and connectivity for animals as well as
places for people to be in nature. Additionally, these elements will be a part of the site
resiliency.
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12. Location of the proposal. Give sufficient information for a person to understand the
precise location of your proposed project, including a street address, if any, and section,
township, and range, if known. If a proposal would occur over a range of area, provide the
range or boundaries of the site(s). Provide a legal description, site plan, vicinity map, and
topographic map, if reasonably available. While you should submit any plans requi red by
the agency, you are not required to duplicate maps or detailed plans submitted with any
permit applications related to this checklist.
The project name is the Longacres Campus Masterplan. The project location is proposed for
the Longacres Office Park (LOP) in Renton, Washington. Within the LOP, the “Site” is
comprised of lots 3, 4, 6, 7, 8, 9, 10,11,12,13, 14, 15, 16, 17, 18, 19, 20, and 21, Tract 1 and
2 of City of Renton LLA No. LUA23-000366, King County Recording No. 20240322000285,
City of Renton, King County, WA.
The address of the site is 1901 Oakesdale Avenue SW. The Site includes one existing office
buildings. Building 25-20 (approximately 311,982 gsf) located at 1901 Oakesdale. The Site
includes maintenance building 25-02 (approximately 25,416 gsf) located at 1302 SW 16th
St. and building 25-03 (approximately 9,945 gsf) located at 1300 Southwest 16th St.
The Project Site overall is approximately 120 acres.
B. Environmental Elements
1. Earth
Find help answering earth questions3
a. General description of the site:
Circle or highlight one: Flat, rolling, hilly, steep slopes, mountainous, other:
The Site is generally flat and located in a floodplain.
b. What is the steepest slope on the site (approximate percent slope)?
Localized slopes adjacent to the existing ponds approach 33%, but generally the
topography is less than 5% with the majority of the area below 2%.
c. What general types of soils are found on the site (for example, clay, sand, gravel, peat,
muck)? If you know the classification of agricultural soils, specify them, and note any
agricultural land of long-term commercial significance and whether the proposal
results in removing any of these soils.
The general subsurface conditions consist of relatively shallow fill overlying alluvium.
The Fill generally consists of very soft to stiff silt with varying amounts of sand, gravel
and organic matter and loose to medium dense sand with varying amounts of silt, gravel
and organic matter. Fill thickness varies across the site and is up to approximately 6 feet
thick. Alluvium was encountered near the existing ground surface or beneath the fill. The
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(WAC 197-11-960)
alluvium generally consists of very soft to medium stiff silt with varying amounts of sand
and organic matter and very loose to medium dense sand with varying amounts of silt,
gravel and organic matter in the upper approximately 20 to 25 feet. Thin layers of peat
and organic silt were observed at various locations across the Longacres Campus within
this upper portion of alluvial soils. Beneath this upper generally fine-grained layer of
alluvium, the unit transitions to denser coarse-grained deposits consisting mostly of sand.
These deeper coarse-grained deposits generally consist of medium dense to dense sand
with varying amounts of silt and gravel. Occasional layers of gravel were observed within
the deeper alluvial soils. Some of the sand and gravel layers are very dense. Although not
encountered in many explorations, occasional large woody debris such as logs exist
within the alluvial soils, and rubble or other debris may be encountered in the fill from
previous grading and development activities.
The ground water levels in the vicinity of the site are expected to fluctuate seasonally and
be near the ground surface during the wet season.
See attached Geotechnical Report by Geotechnical Engineering
R_Geotechnical_Report_250131_v1 for additional information.
d. Are there surface indications or history of unstable soils in the immediate vicinity? If
so, describe.
See attached Geotechnical Report by Geotechnical Engineering
R_Geotechnical_Report_250131_v1 for additional information.
e. Describe the purpose, type, total area, and approximate quantities and total affected
area of any filling, excavation, and grading proposed. Indicate source of fill.
See attached Grading Plans by Coughlin Porter Lundeen for additional information. See
attached P_Civil_Plans_250131_v1
f. Could erosion occur because of clearing, construction, or use? If so, generally describe.
Standard risk of erosion exists due to the nature of construction. Any potential erosion
risk will be mitigated by best management practices as permitted and inspected by the
City of Renton. See attached Geotechnical Report R_Geotechnical_Report_250131_v1
for additional information.
g. About what percent of the site will be covered with impervious surfaces after project
construction (for example, asphalt or buildings)?
The site will target 71% impervious surfaces after project construction, maintaining the
campuses design requirements for this basin.
h. Proposed measures to reduce or control erosion, or other impacts to the earth, if any.
Standard BMPs and code required measures will be implemented prior to earth moving
activated and monitoring will be provided as required by the State and City.
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2. Air
Find help answering air questions4
a. What types of emissions to the air would result from the proposal during construction,
operation, and maintenance when the project is completed? If any, generally describe
and give approximate quantities if known.
Emissions from construction machinery and trucks during construction activities at the
site as well as grading and fill activities could occur. New paving and associated street
and parking lot painting will occur on the site for the new roads and parking areas.
There will be soil removal and adding of soil during construction which will create dust
when there is excavation, grading and filling.
Typically building and site maintenance, and daily operations for the future office, retail
and residential buildings once the masterplan is complete could occur.
b. Are there any off-site sources of emissions or odor that may affect your proposal? If
so, generally describe.
No Off-site is expected.
c. Proposed measures to reduce or control emissions or other impacts to air, if any:
Standard measures will be put in place to reduce and control emissions. Temporary
controls and measures will be put in place during construction that could include wheel
wash stations, crushed rock construction entrances, maintaining clean roadways and
other standard measures.
3. Water
Find help answering water questions5
a. Surface:
Find help answering surface water questions6
1. Is there any surface water body on or in the immediate vicinity of the site
(including year-round and seasonal streams, saltwater, lakes, ponds, wetlands)? If
yes, describe type and provide names. If appropriate, state what stream or river it
flows into.
The site contains two large ponds, Wetland A and Storm Pond B which are located in the
middle of the Site. Additionally there are a number of wetlands of varying sizes and
4 https://ecology.wa.gov/Regulations-Permits/SEPA/Environmental-review/SEPA-guidance/SEPA-checklist-
guidance/SEPA-Checklist-Section-B-Environmental-elements/Environmental-elements-Air
5 https://ecology.wa.gov/Regulations-Permits/SEPA/Environmental-review/SEPA-guidance/SEPA-checklist-
guidance/SEPA-Checklist-Section-B-Environmental-elements/Environmental-elements-3-Water
6 https://ecology.wa.gov/Regulations-Permits/SEPA/Environmental-review/SEPA-guidance/SEPA-checklist-
guidance/SEPA-Checklist-Section-B-Environmental-elements/Environmental-elements-3-Water/Environmental-
elements-Surface-water
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various other stormwater features. At the Northeast corner the Site abuts Springbrook
Creek. See Critical Areas – Existing Conditions Report by PACE Engineers.
2. Will the project require any work over, in, or adjacent to (within 200 feet) the
described waters? If yes, please describe and attach available plans.
Yes, See attached Site Plans.
3. Estimate the amount of fill and dredge material that would be placed in or
removed from surface water or wetlands and indicate the area of the site that
would be affected. Indicate the source of fill material.
The project doesn’t currently propose to dredge or fill any existing wetlands.
Expansion of Pond B is planned to make up for the removal of a separate on-site
detention and floodplain mitigation pond (Kaiser Pond). The source of the fill
material will be determined closer to the expected construction date and further
details will be provided.
4. Will the proposal require surface water withdrawals or diversions? Give a general
description, purpose, and approximate quantities if known.
Additional details will be provided in the EIS process as needed.
5. Does the proposal lie within a 100-year floodplain? If so, note location on the site
plan.
Yes, a significant portion of the proposal lies within a 100-year floodplain. See Site
Plan prepared by Coughlin Porter Lundeen. See attached P_Civil_Plans_250131_v1.
6. Does the proposal involve any discharges of waste materials to surface waters? If
so, describe the type of waste and anticipated volume of discharge.
Additional details will be provided in the EIS process as needed.
b. Ground:
Find help answering ground water questions7
1. Will groundwater be withdrawn from a well for drinking water or other purposes?
If so, give a general description of the well, proposed uses and approximate
quantities withdrawn from the well. Will water be discharged to groundwater?
Give a general description, purpose, and approximate quantities if known.
The proposal does not include a well for groundwater use. The groundwater levels in
the vicinity of the site will fluctuate as a function of season, precipitation and water
levels in the Green River. Based on review of the available subsurface information,
the regional groundwater table in the project varies seasonally at the site and is near
the ground surface elevation during extended periods of wet weather.
2. Describe waste material that will be discharged into the ground from septic tanks
or other sources, if any (domestic sewage; industrial, containing the following
7 https://ecology.wa.gov/Regulations-Permits/SEPA/Environmental-review/SEPA-guidance/SEPA-checklist-
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elements-Groundwater
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chemicals…; agricultural; etc.). Describe the general size of the system, the number
of such systems, the number of houses to be served (if applicable), or the number
of animals or humans the system(s) are expected to serve.
No waste materials are planned to be discharged into the ground.
c. Water Runoff (including stormwater):
1. Describe the source of runoff (including storm water) and method of collection
and disposal, if any (include quantities, if known). Where will this water flow? Will
this water flow into other waters? If so, describe.
Runoff from stormwater will be collected in on-site conveyance systems. The runoff
collected from pollution generating sources will be treated for Enhanced Basic
requirements and discharged into the existing Wetland A and Pond B, both of which
were originally designed as part of the water quality system. Prior to construction, the
civil engineer will prepare a Temporary Erosion and Sediment Control Plan (TESCP) and a
Storm Water Pollution Prevention Plan (SWPPP) for the general contractor to use to
manage stormwater discharge during construction, consistent with applicable
regulations.
2. Could waste materials enter ground or surface waters? If so, generally describe.
Waste materials will be prevented from entering the ground or surface waters with all
runoff from these areas captured and routed through the water quality Enhanced Basic
stormwater treatment vaults proposed.
3. Does the proposal alter or otherwise affect drainage patterns in the vicinity of the
site? If so, describe.
No, the proposal does not alter drainage patterns in the vicinity of the site.
d. Proposed measures to reduce or control surface, ground, and runoff water, and
drainage pattern impacts, if any:
See the attached Stormwater Management Plan and Drainage report prepared by
Coughlin Porter Lundeen. See attached P_Civil_Plans_250131_v1.
4. Plants
Find help answering plants questions
a. Check the types of vegetation found on the site:
☒ deciduous tree: alder, maple, aspen, other
☒ evergreen tree: fir, cedar, pine, other
☒ shrubs
☒ grass
☐ pasture
☐ crop or grain
SEPA Environmental checklist September 2023 Page 9
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☐ orchards, vineyards, or other permanent crops.
☒ wet soil plants: cattail, buttercup, bullrush, skunk cabbage, other
☒ water plants: water lily, eelgrass, milfoil, other
☒ other types of vegetation
b. What kind and amount of vegetation will be removed or altered?
c. List threatened and endangered species known to be on or near the site.
See Critical Areas Report with conceptual mitigation plan dated January 2025, prepare d
by PACE Engineers, Inc. The report includes a biological evaluation and habitat
assessment in Section 6. The biological and habitat assessment identifies six ESA -listed
species and essential fish habitat within the project area. The report concludes that t he
construction and operation of the proposed development is not likely to directly affect
any ESA-listed species or habitat and will not result in a “take” as defined by the
Endangered Species Act. See attached RS_Criticial_Areas_Report_250131_v1.
d. Proposed landscaping, use of native plants, or other measures to preserve or enhance
vegetation on the site, if any.
See attached Conceptual Landscape Plan by Hewitt Architects. See
P_Landscape_Plans_250131_v1.
e. List all noxious weeds and invasive species known to be on or near the site.
invasive Himalayan blackberry ( Rubus armeniacus), reed canary grass ( Phalaris
arundinacea), and English Ivy (Hedera helix) are on site and are listed as invasive. See
Critical Areas Report by PACE Engineers for additional information. See attached
RS_Criticial_Areas_Report_250131_v1.
5. Animals
Find help answering animal questions8
a. List any birds and other animals that have been observed on or near the site or are
known to be on or near the site.
Birds: Duck, Geese, Herons, Eagles, Hawks, Songbirds, Other
Mammals: Coyote, Rabbits, Squirrels, Raccoon, Moles
Fish: Trout, Other
Reptiles: Turtles, Other
Examples include:
• Birds: hawk, heron, eagle, songbirds, other:
8 https://ecology.wa.gov/Regulations-Permits/SEPA/Environmental-review/SEPA-guidance/SEPA-checklist-
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SEPA Environmental checklist September 2023 Page 10
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• Mammals: deer, bear, elk, beaver, other:
• Fish: bass, salmon, trout, herring, shellfish, other:
b. List any threatened and endangered species known to be on or near the site.
c. Six ESA-listed species are potentially within the project area as discussed in Section 6 –
Habitat, of the Critical Areas Report dated January 2025. The following species are
potentially present in the project area:
d. Puget Sound ESU Chinook Salmon (Oncorhynchus tshawytscha)
e. Puget Sound Steelhead DPS (Oncorhynchus mykiss)
f. Coastal/Puget Sound Bull Trout ( Salvelinus confluentus)
g. North American Wolverine (Gulo gulo luscus)
h. Marbled Murrelet (Brachyramphus marmoratus)
i. Western Yellow-billed Cuckoo (Coccyzus americanus)
j. While there is no fish access available to the site from adjacent streams, resident and
anadromous fish, including Chinook, pink, sockeye, chum and coho salmon, cutthroat
trout, and winter steelhead have been observed throughout the basin and in proximity
to the site (King County 2016). In addition, National Marine Fisheries NOAA have
designated the Puget Sound and its watershed as Essential Fish Habitat for Chinook,
coho, and pink salmon. Two ESA-listed salmon species have designated critical habitat
outside the Project area, at Springbrook Creek (70 FR 52629; 81 FR 9251). However, the
listed species and their habitat have not been documented within the area proposed for
redevelopment.
k. Is the site part of a migration route? If so, explain.
l. Yes. The Puget Sound is located within the Pacific Flyway Migratory Bird route.
m. Proposed measures to preserve or enhance wildlife, if any.
None. Impacts to wildlife are not anticipated.
n. List any invasive animal species known to be on or near the site.
None Known.
6. Energy and natural resources
Find help answering energy and natural resource questions9
a. What kinds of energy (electric, natural gas, oil, wood stove, solar) will be used to meet
the completed project's energy needs? Describe whether it will be used for heating,
manufacturing, etc.
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The Longacres Master Plan proposes to plan for electric and natural gas to be available
at the Site for future development. This will be used for heating, cooling and power in
typical residential, commercial, retail, music venue, light industrial and hotel use. The
site also has a Central Utility Plant that could be expanded to provide heating and
cooling to more buildings.
b. Would your project affect the potential use of solar energy by adjacent properties? If
so, generally describe.
The additional buildings and trees planned on the Site for the Longacres Master Plan
could cast shadows on adjacent properties. The Site is bordered by 405 to the North,
BNSF Railway to the West and Springbrook Creek and a few Industrial Buildings to the
East, greatly reducing the affect on potential use of solar energy.
c. What kinds of energy conservation features are included in the plans of this proposal?
List other proposed measures to reduce or control energy impacts, if any.
None.
7. Environmental health
Health Find help with answering environmental health questions10
a. Are there any environmental health hazards, including exposure to toxic chemicals,
risk of fire and explosion, spill, or hazardous waste, that could occur because of this
proposal? If so, describe.
1. Describe any known or possible contamination at the site from present or past
uses.
The broader Longacres Site has been the subject of subsurface environmental
assessments completed for Boeing. The assessments identified limited soil and
groundwater impacts associated with former racetrack operations, specifically in
areas of former maintenance operations. Remediation activities were subsequently
completed by Boeing in areas of maintenance shops, which included the removal of
five underground storage tanks and excavation of petroleum contaminated soil and
groundwater monitoring. No Further Action determinations were issued by the WA
State Dept. of Ecology in 2011 for releases associated with the former USTs. There is
a NFA from the WA Dept of Ecology to address contamination on the Longacres site
where a previous racetrack was located.
In addition, all construction activities will be subject to a construction mitigation
plan and BMPs. When required supplemental soil management plans as identified in
the Unico-Boeing CCRs, which exceed any obligations required under federal, state,
or local regulations will be prepared and implemented.
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Information from the Ecology Tacoma Smelter Plume website indicates the site is in
the area potentially impacted by the ASARCO Company smelter Plume. There is no
site-specific information regarding concentrations of arsenic and lead, but such
contaminants could be present on the site. Reports show that sampling was
completed at the Bright Horizons Daycare Center across Oakesdale by King County
Health Department under Ecology’s Soil Safety Program for childcare centers that
meet state standards. Soil testing and soil management plans will meet any
obligations under federal, state or local regulations, including the Tacoma Smelter
Plume Remedies Guidance prepared by the Department of Ecology.
2. Describe existing hazardous chemicals/conditions that might affect project
development and design. This includes underground hazardous liquid and gas
transmission pipelines located within the project area and in the vicinity.
None are known at this time.
3. Describe any toxic or hazardous chemicals that might be stored, used, or produced
during the project's development or construction, or at any time during the
operating life of the project.
Not known at this time, but the applicant does expect that fuel for equipment may
be stored on site during construction and would be subject to proper spill control
measures per the Department of Ecology requirements. When needed any toxic or
hazardous chemicals being used, stored or produced on site during construction or
operation would be handled in accordance with applicable regulations.
4. Describe special emergency services that might be required.
None known at this time to be required.
5. Proposed measures to reduce or control environmental health hazards, if any.
During the construction process personnel will attend to fueling process to ensure
any spills will be limited volume and a full spill response kit will be maintained on
site in case of any accident.
b. Noise
1. What types of noise exist in the area which may affect your project (for example:
traffic, equipment, operation, other)?
Traffic.
2. What types and levels of noise would be created by or associated with the project
on a short-term or a long-term basis (for example: traffic, construction, operation,
other)? Indicate what hours noise would come from the site)?
Construction noise during the construction phases at the Site. Typically traffic and
operation noise are expected with the types of proposed site uses during the day.
The proposed music venue will have evening shows on weekend days and evenings
from approximately May to October.
3. Proposed measures to reduce or control noise impacts, if any:
SEPA Environmental checklist September 2023 Page 13
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Noise impacts outside of the music venue will be avoided by compliance with the
Renton noise code (RMC ch. 8-7). With no immediate neighbors in the office park,
no nearby residential receiving sites, and given the proximity and noise generated by
Interstate 405, noise is not anticipated to affect, burden or create a nuisance to any
other property owner or user. The proposed location of the music venue which is
away from residential uses, the limited yearly schedule and evening hours are
proposed to help minimize and control the noise impacts at the site.
8. Land and shoreline use
Find help answering land and shoreline use questions11
a. What is the current use of the site and adjacent properties? Will the proposal affect
current land uses on nearby or adjacent properties? If so, describe.
The Site has been used as office space and industrial. Adjacent properties include
medical offices, daycare, and commercial airlines uses, and are separated from the
Project site by, right of way, vacant, or undevelopable land. The proposed use is office
space, retail, hotel, music venue, residential, medical office building and light industrial.
The proposal is not expected to affect current land uses on nearby or adjacent
properties.
b. Has the project site been used as working farmlands or working forest lands? If so,
describe. How much agricultural or forest land of long-term commercial significance
will be converted to other uses because of the proposal, if any? If resource lands have
not been designated, how many acres in farmland or forest land tax status will be
converted to nonfarm or nonforest use?
The Site was used as farmland in the early 20th Century. Any farmland on the Site was
converted decades ago with the development of the Longacres racetrack and the
subsequent redevelopment of the Boeing Headquarters.
No agricultural or forest land of long-term significance will be converted to other uses as
a result of this proposal.
1. Will the proposal affect or be affected by surrounding working farm or forest
land normal business operations, such as oversize equipment access, the
application of pesticides, tilling, and harvesting? If so, how?
No.
c. Describe any structures on the site.
The Site includes one existing office buildings. Building 25-20 (approximately 311,982
gsf) located at 1901 Oakesdale Ave SW. The Site includes maintenance building 25-02
(approximately 25,416 gsf) located at 1302 SW 16th St. and building 25 -03
(approximately 9,945 gsf) located at 1300 SW 16th St. and building 25-01
(approximately 21,083 gsf) at 1900 Oakesdale Ave SW.
11 https://ecology.wa.gov/Regulations-Permits/SEPA/Environmental-review/SEPA-guidance/SEPA-checklist-
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d. Will any structures be demolished? If so, what?
Yes, building 25-01 located at 1900 Oakesdale Ave SW and the maintenance building
1300 SW 16th St. will be demolished.
e. What is the current zoning classification of the site?
CO-commercial Office and IM- Industrial Medium are the current zoning classification of
the Site.
What is the current comprehensive plan designation of the site?
The Comprehensive Plan Land Use Designation for the Site is Employment Area (“EA”)
f. If applicable, what is the current shoreline master program designation of the site?
A portion of the Site is withing the Shoreline Jurisdiction for the City of Renton. Parcel
2423049022 is adjacent to Springbrook Creek to the East and a section of regulated
Shoreline, BRSC-B Black River/Springbrook Creek Reaches.
g. Has any part of the site been classified as a critical area by the city or county? If so,
specify.
Yes, Wetlands and Streams on or adjacent to the Site are classified as critical areas by
the City of Renton.
h. Approximately how many people would reside or work in the completed project?
Approximately 10,000-12,000 people would reside or work in the completed project.
i. Approximately how many people would the completed project displace?
The completed project will displace no people.
j. Proposed measures to avoid or reduce displacement impacts, if any.
The completed project will displace no people.
k. Proposed measures to ensure the proposal is compatible with existing and projected
land uses and plans, if any.
None.
l. Proposed measures to reduce or control impacts to agricultural and forest lands of
long-term commercial significance, if any:
None.
9. Housing
Find help answering housing questions12
Approximately how many units would be provided, if any? Indicate whether high,
middle, or low-income housing.
Approximately 3,000 units are proposed to be provided at the Site.
12 https://ecology.wa.gov/Regulations-Permits/SEPA/Environmental-review/SEPA-guidance/SEPA-checklist-
guidance/SEPA-Checklist-Section-B-Environmental-elements/Environmental-elements-9-Housing
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(WAC 197-11-960)
a. Approximately how many units, if any, would be eliminated? Indicate whether high,
middle, or low-income housing.
No units are eliminated in this proposal.
b. Proposed measures to reduce or control housing impacts, if any:
None. No units are eliminated in this proposal.
10. Aesthetics
Find help answering aesthetics questions13
a. What is the tallest height of any proposed structure(s), not including antennas; what is
the principal exterior building material(s) proposed?
All parcels are restricted by the FAA airport height restrictions. All illustrative
buildings are below this elevation which varies based on the overlay of this
requirement. The building heights exemplified in the illustrative plan vary from 56-
feet to 170-feet. There are no materials currently designated for the illustrative plan
since the buildings shown are not final designs. Any future design will comply with
the design guidelines outlines in RMC 4-3-100.
b. What views in the immediate vicinity would be altered or obstructed?
The interior parcels associated with the Longacres parcels are illustratively proposed
to consolidate and define building massing and provide a vantage point to view the
natural common open space of the wetlands. Those parcels located along Oaksdale
demonstrate building massing which further define the public way. These buildings
are proposed to be tall enough to create a vantage point for viewing the campus of
buildings and the shared natural common space.
c. Proposed measures to reduce or control aesthetic impacts, if any :
There will be future opportunities to review aesthetic impacts once individual parcels
are developed. The Master Plan Development Agreement, The Planned Urban
Development Plan will also be put in place and are proposed measure to control
aesthetic impacts for the Longacres Campus.
11. Light and glare
Find help answering light and glare questions14
a. What type of light or glare will the proposal produce? What time of day would it
mainly occur?
Although the site and building lighting system and fixtures have not yet been chosen,
lighting will be selected to reduce glare and light pollution. Lighting will be directed to
focus on streets, sidewalks and public plazas to provide a night-time safe environment.
13 https://ecology.wa.gov/Regulations-Permits/SEPA/Environmental-review/SEPA-guidance/SEPA-checklist-
guidance/SEPA-Checklist-Section-B-Environmental-elements/Environmental-elements-10-Aesthetics
14 https://ecology.wa.gov/Regulations-Permits/SEPA/Environmental-review/SEPA-guidance/SEPA-checklist-
guidance/SEPA-Checklist-Section-B-Environmental-elements/Environmental-elements-11-Light-glare
SEPA Environmental checklist September 2023 Page 16
(WAC 197-11-960)
b. Could light or glare from the finished project be a safety hazard or interfere with
views?
None known at this time.
c. What existing off-site sources of light or glare may affect your proposal?
There are no known off-site sources of light or glare that would affect the current
proposal.
d. Proposed measures to reduce or control light and glare impacts, if any:
It is the intention that any future measures to control light and glare would implement
dark-sky compliance and be designed to limit impact on wetlands and critical areas.
12. Recreation
Find help answering recreation questions
a. What designated and informal recreational opportunities are in the immediate
vicinity?
There are walking and biking trails in the Longacres Campus. There is a pedestrian and bike
path that connects the Tukwila Sounder Train station to the West of the property with the
Eastern side of the property. There are a number of opportunities along th e various walking
and biking paths on the property to view the wetlands, ponds and wildlife. See Site Plan for
map of paths. To the Northwest of the Site is Tukwila Park and to the West the Green River
and Green River Trail. To the Northwest is the Starfire Sports Fields, which are the Sounders
current practice facilities. The east is the Springbrook trail and Springbrook Creek.
b. Would the proposed project displace any existing recreational uses? If so, describe.
The Project proposes to keep the existing trails through the Site. There may be some
impacts to wildlife viewing with added trails, roads and building.
c. Proposed measures to reduce or control impacts on recreation, including recreation
opportunities to be provided by the project or applicant, if any:
The project proposes to maintain existing opportunities for wildlife viewing when feasible
as well as add more trails and park areas to the Site.
13. Historic and cultural preservation
Find help answering historic and cultural preservation questions15
a. Are there any buildings, structures, or sites, located on or near the site that are over
45 years old listed in or eligible for listing in national, state, or local preservation
registers? If so, specifically describe.
None. Boeing constructed the existing buildings and related infrastructure on the Site
within the last 45 years. None of the building, structures, or site is listed on or eligible
for listing in the National or state preservation registers.
15 https://ecology.wa.gov/Regulations-Permits/SEPA/Environmental-review/SEPA-guidance/SEPA-checklist-
guidance/SEPA-Checklist-Section-B-Environmental-elements/Environmental-elements-13-Historic-cultural-p
SEPA Environmental checklist September 2023 Page 17
(WAC 197-11-960)
b. Are there any landmarks, features, or other evidence of Indian or historic use or
occupation? This may include human burials or old cemeteries. Are there any material
evidence, artifacts, or areas of cultural importance on or near the site? Please list any
professional studies conducted at the site to identify such resources.
None known. See Renton/Boeing 1994 DEIS for the Longacres Office Park, Ch. 13 (
Historical Resources) and the 1995 FEIS for an extensive study of historical and cultural
resources for the Longacres Campus.
Professional Studies are associated with the SHPO Determination 072192-01-K1
Resource Inventory 10/7/1992 ( SHPO Determined date 06/16/2008). Longacres Park
was not included in the State or National Registers of Historic Places because the
collective alterations to the site were too great to meet the integrity criteria as
described in a Letter from the Office of Archaeology and Historic Preservation dated
May 18, 1993, which provided the outcome of the council’s review. Construction since
1992 would be less than 45 years old and thereby excluded.
c. Describe the methods used to assess the potential impacts to cultural and historic
resources on or near the project site. Examples include consultation with tribes and
the department of archeology and historic preservation, archaeological surveys,
historic maps, GIS data, etc.
Review and analysis of the following:
• Renton/Boeing 1994 DEIS, Ch. 13 ( Historical Resources), Renton/Boeing FEIS,
and other environmental review documents associated with Longacres ( with
attention to historical resources)
• Muckleshoot Indian Tribe Comment letters regarding proposed development at
Longacres requesting notification if any resources are found during excavation)
Subsequent SEPA checklists for proposed Longacres improvements.
• DAHP WISSARD database.
• Puget Sound archives.
• King County GIS Maps and City of Renton Maps.
The DEIS, DAHP database, and the archives included historical materials on the
development and use of the Site and broader Campus dating back to “Western”
settlement. The site has been redeveloped on at least three separate occasions: ( 1)
farming, ( 2) Longacres horse racetrack, ( 3) Boeing Headquarters, which included
extensive stormwater and drainage facilities in the fields surrounding Building 25 -20.
The Boeing Longacres Campus was developed in phases. The checklist associated with
each phase notes that previous development did not find any potential archeological
evidence. Thus, it is highly likely that this proposal will not encounter any potential
archeological evidence, especially since this area of the Campus was already developed.
d. Proposed measures to avoid, minimize, or compensate for loss, changes to, and
disturbance to resources. Please include plans for the above and any permits that may
be required.
No permits are required. Extensive redevelopment activity has already occurred at the
Site with no findings of any resources. However, the applicant will halt work and contact
SEPA Environmental checklist September 2023 Page 18
(WAC 197-11-960)
the City of Renton, DAHP, and the Muckleshoot Indian Tribe if any potential
archeological evidence is encountered during site work.
14. Transportation
Find help with answering transportation questions16
a. Identify public streets and highways serving the site or affected geographic area and
describe proposed access to the existing street system. Show on site plans, if any.
Traffic Engineers North West has prepared the attached traffic scoping memo and will
work to develop the study for the Project. Additional information will be provided
during the EIS process. See attached
RS_Longacres_Master_Plan_Trip_Generation_and_Scoping_Memorandum_250131_v1
b. Is the site or affected geographic area currently served by public transit? If so,
generally describe. If not, what is the approximate distance to the nearest transit
stop?
The Tukwila Sounders Train Stop is within approximately ¼ mile of the site and
Oakesdale has a bus route with the nearest stop adjacent to Eastern board of the site
(within 100’).
c. Will the proposal require any new or improvements to existing roads, streets,
pedestrian, bicycle, or state transportation facilities, not including driveways? If so,
generally describe (indicate whether public or private).
Yes, the proposal will require new roads, paths, stormwater conveyance, lighting,
signage and other roadway infrastructure. See attached Site Plan for proposed road
layout. The Project proposes that there will be a combination of public and private
ownership. See attached P_Civil_Plans_250131_v1.
d. Will the project or proposal use (or occur in the immediate vicinity of) water, rail, or
air transportation? If so, generally describe.
The project will use the Sounders Train for people to commute to and from the site or
visit the site from Seattle and other stations on the Sounders Train Line. There is also a
bus stop for the King County Metro F Bus Rapidride on Oakesdale near Building 2 5-20,
which links to the Tukwila Transit Center, and Burien Transit Center, and the Landing.
e. How many vehicular trips per day would be generated by the completed project or
proposal? If known, indicate when peak volumes would occur and what percentage of
the volume would be trucks (such as commercial and nonpassenger vehicles). What
data or transportation models were used to make these estimates?
Traffic Engineers North West has prepared the attached traffic scoping memo and will
work to develop the study for the Project. Additional information will be provided
during the EIS process. See attached
RS_Longacres_Master_Plan_Trip_Generation_and_Scoping_Memorandum_250131_v1
16 https://ecology.wa.gov/Regulations-Permits/SEPA/Environmental-review/SEPA-guidance/SEPA-checklist-
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f. Will the proposal interfere with, affect, or be affected by the movement of agricultural
and forest products on roads or streets in the area? If so, generally describe.
No.
g. Proposed measures to reduce or control transportation impacts, if any:
Traffic Engineers North West has prepared the attached traffic scoping memo and will
work to develop the study for the Project. Additional information will be provided
during the EIS process. See attached
RS_Longacres_Master_Plan_Trip_Generation_and_Scoping_Memorandum_250131_v1
15. Public services
Find help answering public service questions17
a. Would the project result in an increased need for public services (for example: fire
protection, police protection, public transit, health care, schools, other)? If so,
generally describe.
Yes with the additional buildings there will be an increase in the need for fire protection
and police protection. Additionally, there will be an increase in the need for schools with
the addition of residential units.
b. Proposed measures to reduce or control direct impacts on public services, if any.
These measures are anticipated to be defined and put in place during the EIS and
permitting process.
16. Utilities
Find help answering utilities questions18
a. Circle utilities currently available at the site: electricity, natural gas, water, refuse
service, telephone, sanitary sewer, septic system, other:
b. Describe the utilities that are proposed for the project, the utility providing the
service, and the general construction activities on the site or in the immediate vicinity
which might be needed.
The proposal includes expansion of existing utilities currently available at the site. New
electrical, natural gas, water, refuse service, telephone, and sanitary sewer networks
will be constructed as proposed in the Master Plan drawings. See attached
P_Civil_Plans_250131_v1.
17 https://ecology.wa.gov/regulations-permits/sepa/environmental-review/sepa-guidance/sepa-checklist-
guidance/sepa-checklist-section-b-environmental-elements/environmental-elements-15-public-services
18 https://ecology.wa.gov/regulations-permits/sepa/environmental-review/sepa-guidance/sepa-checklist-
guidance/sepa-checklist-section-b-environmental-elements/environmental-elements-16-utilities
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C. Signature
Find help about who should sign19
The above answers are true and complete to the best of my knowledge. I understand that the
lead agency is relying on them to make its decision.
Recoverable Signature
X Julia Reeve
Signed by: 45668a6a-d28e-448c-b130-0fc12de17265
Type name of signee:
Position and agency/organization:
Date submitted:
D. Supplemental sheet for nonproject actions
Find help for the nonproject actions worksheet20
Do not use this section for project actions.
Because these questions are very general, it may be helpful to read them in conjunction with
the list of the elements of the environment.
When answering these questions, be aware of the extent the proposal, or the types of activities
likely to result from the proposal, would affect the item at a greater intensity or at a faster rate
than if the proposal were not implemented. Respond briefly and in general terms.
1. How would the proposal be likely to increase discharge to water; emissions to air;
production, storage, or release of toxic or hazardous substances; or production of
noise?
• Proposed measures to avoid or reduce such increases are:
2. How would the proposal be likely to affect plants, animals, fish, or marine life?
• Proposed measures to protect or conserve plants, animals, fish, or marine life are:
19 https://ecology.wa.gov/Regulations-Permits/SEPA/Environmental-review/SEPA-guidance/SEPA-checklist-
guidance/SEPA-Checklist-Section-C-Signature
20 https://ecology.wa.gov/regulations-permits/sepa/environmental-review/sepa-guidance/sepa-checklist-
guidance/sepa-checklist-section-d-non-project-actions
SEPA Environmental checklist September 2023 Page 21
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3. How would the proposal be likely to deplete energy or natural resources?
• Proposed measures to protect or conserve energy and natural resources are:
4. How would the proposal be likely to use or affect environmentally sensitive areas or
areas designated (or eligible or under study) for governmental protection, such as
parks, wilderness, wild and scenic rivers, threatened or endangered species habitat,
historic or cultural sites, wetlands, floodplains, or prime farmlands?
• Proposed measures to protect such resources or to avoid or reduce impacts are:
5. How would the proposal be likely to affect land and shoreline use, including whether it
would allow or encourage land or shoreline uses incompatible with existing plans ?
• Proposed measures to avoid or reduce shoreline and land use impacts are:
6. How would the proposal be likely to increase demands on transportation or public
services and utilities?
• Proposed measures to reduce or respond to such demand(s) are:
7. Identify, if possible, whether the proposal may conflict with local, state, or federal laws
or requirements for the protection of the environment.