HomeMy WebLinkAboutSR_HEX_Report_Exhibits_Combined_LUA18000188DEPARTMENT OF COMMUNITY
AND ECONOMIC DEVELOPMENT
Project Location Map
HEX ReportHEX_Report_18-000188_180417_v1
A. REPORT TO THE HEARING EXAMINER
HEARING DATE: April 17, 2018
Project Name: King County South Plant Biogas and Heating Systems Improvements Project
Owner/Applicant: Chris Dew, King County Wastewater Treatment Division, King Street Center, 201 S
Jackson St, Seattle, WA 98104
Contact: Karmen Martin, ESA | Environmental Science Associates, 5309 Shilshole Ave NW,
Suite 200, Seattle, WA 98107
Project File Number: PR16-000503
Land Use File Number: LUA18-000188, SA-A, CU-H, SME, MOD
Project Manager: Clark H. Close, Senior Planner
Project Summary: King County (KC) is requesting Administrative Site Plan Review, Hearing Examiner
Conditional Use Permit, Shoreline Exemption, and a Street Modification to replace
South Plant's Biogas Upgrading System and heating system to improve the beneficial
use of digester gas at KC Wastewater Treatment Division's South Treatment Plant
(STP) while also reliably supplying heat to meet process and space heating demands.
The proposed project is located on parcel nos. 423049006, -9097 and -9111). The
South Plant Biogas and Heating Systems Project would include the construction of a
Heat and Energy Recovery Building, a new thermal oxidizer, heating system
improvements within the Digester Equipment Building, and utility connections.
The parcel contains one Category IV wetland and a flood hazard area is mapped on
a portion of the project site. No work would be completed within either the wetland
or the wetland buffer. No permanent facilities or fill would be located within the
mapped flood hazard area. Roughly 17,000 cubic yards of soil would be excavated
and placed on a 1-acre area on open lawn within the center of the STP site. Spoils
would be compacted and seeded to match existing grades and vegetation type.
A temporary stabilized construction entrance would provide construction
machinery access to the proposed spoils placement area onsite and would require
approximately 290 cubic yards of cut soil and approximately 120 cubic yards of
quarry spalls. Following grading activities on the spoils placement site, the
temporary stabilized construction entrance would be removed, grades would be
restored to their preconstruction condition, and the area would be permanently
stabilized with mulch followed by seeding.
Project Location: 1200 Monster Rd SW, Renton, WA 98057
Site Area: 191,824 SF (4.4 acres of the 50-acre STP site)
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 2 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
B. EXHIBITS:
Exhibit 1: Hearing Examiner Staff Recommendation (dated April 17, 2018)
Exhibit 2: Environmental (SEPA) Determination of Nonsignificance (DNS) (dated March 5, 2018)
Exhibit 3: Environmental Checklist
Exhibit 4: Vicinity Map
Exhibit 5: Neighborhood Detail Map
Exhibit 6: Site Plan
Exhibit 7: Conceptual Color Building Renderings
Exhibit 8: Architectural Exterior Elevations
Exhibit 9: Floor Plans
Exhibit 10: Tree Report, prepared by Russell + Lambert Landscape Architecture, dated February 15,
2018
Exhibit 11: Landscape and Tree Retention Plans
Exhibit 12: Civil Construction Plans
Exhibit 13: Construction Mitigation Description
Exhibit 14: Geotechnical Engineering Report, prepared by Shannon & Wilson, Inc. dated January 6,
2017
Exhibit 15: Addendum to Geotechnical Engineering Report, prepared by Shannon & Wilson, Inc. dated
March 16, 2017
Exhibit 16: Geotechnical Engineering Report Addendum, prepared by Shannon & Wilson, Inc. dated
December 8, 2017
Exhibit 17: Technical Information Report (Full Drainage Review), prepared by Davido Consulting Group
(DCG), Inc., dated February 2018
Exhibit 18: Trip Generation Memorandum, prepared by Brown and Caldwell, dated November 30,
2017
Exhibit 19: Wetland Assessment Report, prepared by Environmental Science Associates (ESA), dated
January 2018
Exhibit 20: Standard Stream Study, prepared by ESA, dated January 5, 2018
Exhibit 21: Temporary Construction Entrance Site Plan
Exhibit 22: Street Modification Request
Exhibit 23: Advisory Notes to Applicant
C. GENERAL INFORMATION:
1. Owner(s) of Record: King County Wastewater Treatment Division
(WTD). Contact: Chris Dew, King County WTD, King
Street Center, 201 S Jackson St, Seattle, WA 98104
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 3 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
2. Owner(s) of Record: King County Wastewater Treatment Division
(WTD). Contact: Chris Dew, King County WTD, King
Street Center, 201 S Jackson St, Seattle, WA 98104
3. Zoning Classification: Heavy Industrial (IH)
4. Comprehensive Plan Land Use Designation: Employment Area (EA)
5. Existing Site Use: Public utility (the King County Treatment Plant)
6. Critical Areas: Regulated Slopes (>15% & <=90%), Regulated
Shorelines: Shoreline High Intensity, BRSC-A Black
River/Springbrook Creek Reaches, Moderate/High
Coal Mine Hazards, High Seismic Hazard Areas,
Moderate/High Landslide Hazards, 100-year flood
Hazard Areas (FEMA Zone – AE), Wetlands, and
Springbrook Creek Buffer
7. Neighborhood Characteristics:
a. North: Waterworks Gardens and Vacant Land north of Oakesdale Ave SW. Employment
Area (EA) land use designation and Commercial Office (CO) zoning.
b. East: Office Buildings east of Oakesdale Ave SW. Employment Area (EA) land use
designation and Commercial Office (CO) zoning.
c. South: Office Buildings, Warehouse and Vacant Land. Employment Area (EA) land use
designation and Medium Industrial (IM) zoning.
d. West:
Warehouse, Office, Packaging Plant, Minerals Yard, and Vacant Land west of
Monster Rd SW/Jackson Pl SW. Employment Area (EA) land use designation and
Medium Industrial (IM) zoning.
6. Site Area: 4.4 acres
D. HISTORICAL/BACKGROUND:
Action Land Use File No. Ordinance No. Date
Comprehensive Plan N/A 5758 06/22/2015
Zoning N/A 5758 06/22/2015
Annexation (S 180th) A-002-59 1745 04/19/1959
Conditional Use Permit
(Effluent Reuse Pilot Project)
LUA95-073 N/A 04/28/1995
Temporary Use Permit
(Install/Operate Sludge
Reduction Building)
LUA99-129 N/A 09/14/1999
Shoreline Substantial
Development Permit (Odor
Control System for the
Eastside Sewer Interceptor)
LUA00-017 N/A 02/08/2000
Temporary Use Permit
(Diesel Generators)
LUA01-022 N/A 02/20/2001
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 4 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
Conditional Use Permit
(Construct a Fuel Cell
Demonstration Project)
LUA01-138 N/A 10/03/2001
Conditional Use Permit
(Construct a cogeneration
facility)
LUA03-099 N/A 10/07/2003
E. PUBLIC SERVICES:
1. Existing Utilities
a. Water: Water service will be provided by the City of Renton. Water service for the existing building
shall be serviced by the existing private 12” CW line that loops around the property. Applicant is to
ensure that the water line that they connect to is the correct line.
b. Sewer: Sewer service is provided by the City of Renton. There is an existing 12-inch wastewater
main located in Oakesdale Ave SW (see City plan no. S-199807).
c. Surface/Storm Water: There is an existing storm water system within the property.
2. Streets: The applicant has submitted a street modification that was approved through the latest project
within the King County Waste Water treatment facility. This waiver was approved by the City of Renton
on January 20, 2017.
3. Fire Protection: Renton Regional Fire Authority (RRFA)
F. APPLICABLE SECTIONS OF THE RENTON MUNICIPAL CODE:
1. Chapter 2 Land Use Districts
a. Section 4-2-020: Purpose and Intent of Zoning Districts
b. Section 4-2-060: Zoning Use Table – Uses Allowed in Zoning Designations
c. Section 4-2-130: Industrial Development Standards
2. Chapter 4 City-Wide Property Development Standards
3. Chapter 6 Streets and Utility Standards
a. Section 4-6-060: Street Standards
4. Chapter 9 Permits – Specific
a. Section 4-9-030: Conditional Use Permits
b. Section 4-9-200: Master Plan and Site Plan Review
c. Section 4-9-250: Variances, Waivers, Modifications, and Alternates
5. Chapter 11 Definitions
G. APPLICABLE SECTIONS OF THE COMPREHENSIVE PLAN:
1. Land Use Element
H. FINDINGS OF FACT (FOF):
1. The Planning Division of the City of Renton accepted the above master application for review on March
12, 2018 and determined the application complete on March 15, 2018. The project complies with the
120-day review period.
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 5 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
2. The site area is approximately 4.4 acres and the site is located at 1200 Monster Rd SW near the
Renton/Tukwila border (Exhibits 3 and 4).
3. The project site is currently developed as King County South Treatment Plant.
4. No changes to vehicular or pedestrian access to the site would occur as a result of the project. Access to
the site is provided via Monster Rd SW and SW 7th St (Exhibit 5).
5. The project site is located towards the north/central portion of the lot. The construction of a new Heating
and Energy Recovery Building (HERB) and associated driveway, uncovered parking stalls, walkways,
concrete equipment pads, stormwater improvements, utility connections, and landscaping consists of
approximately 191,824 square feet of the site (Exhibit 6).
6. The property is located within the Employment Area (EA) Comprehensive Plan land use designations.
7. The site is located within the Heavy Industrial (IH) zoning classification.
8. There are approximately 180 significant trees located onsite of which the applicant is proposing to retain
138 trees (Exhibits 10 and 11).
9. The site is mapped with the following critical areas: regulated slopes (>15% & <=90%), regulated
shorelines: Shoreline High Intensity, BRSC-A Black River/Springbrook Creek Reaches, moderate/high coal
mine hazards, high seismic hazard areas, moderate/high landslide hazards, 100-year flood hazard area
(FEMA Zone – AE) associated with Springbrook Creek, and one Category IV wetland (Wetland A)
approximately 1,000 feet from the Black River and 250 to 450 feet from Springbrook Creek. No work
would be completed within either the wetland or the wetland buffer (Exhibits 19 and 20).
10. Approximately 17,000 cubic yards of soil would be excavated and placed on a 1-acre area on open lawn
within the center of the STP site. Spoils would be compacted and seeded to match existing grades and
vegetation type.
11. A temporary stabilized construction entrance would provide construction machinery access to the
proposed spoils placement area onsite. Construction and use of the temporary construction entrance
would occur within a portion of the shoreline jurisdiction of Springbrook Creek. The temporary
construction entrance would require approximately 290 cubic yards of cut soil and approximately 120
cubic yards of quarry spalls. Following grading activities on the spoils placement site, the temporary
stabilized construction entrance would be removed, grades would be restored to their preconstruction
condition, and the area would be permanently stabilized with mulch followed by seeding (Exhibit 21).
12. The applicant is proposing to begin construction in May 2019 and end in May 2021 (Exhibits 3 and 13).
13. No other public or agency comments were received.
14. On March 5, 2018, King County (SEPA lead agency), issued a Determination of Non-significance (DNS) for
the South Plant Biogas and Heating Systems Improvements (Exhibit 2). This decision was made after
review of a completed Environmental Checklist, the environmental reports and other information on file
with the lead agency (Exhibit 3).
15. Representatives from various city departments have reviewed the application materials to identify and
address issues raised by the proposed development. These comments are contained in the official file,
and the essence of the comments has been incorporated into the appropriate sections of this report and
the Departmental Recommendation at the end of this report (Exhibit 23).
16. Comprehensive Plan Compliance: The site is designated Employment Area (EA) on the City’s
Comprehensive Plan Map. The EA designation provides a significant economic development and
employment base for the City. Maintain a variety and balance of uses through zoning that promotes the
gradual transition of uses on sites with good access and visibility to more intensive commercial and office
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 6 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
uses. The proposal is compliant with the following development standards if all conditions of approval
are met:
Compliance Comprehensive Plan Analysis
Goal L-M: Strengthen Renton’s employment base and economic growth by achieving a
mix of industrial, high technology, office, and commercial activities in Employment
Areas.
Goal L-P: Minimize adverse impacts to natural systems, and address impacts of past
practice where feasible, through leadership, policy, regulation, and regional
coordination.
Goal L-U: Preserve, protect, and enhance the quality and functions of the City’s sensitive
areas including: lakes, rivers, major and minor creeks, intermittent stream courses and
their floodplains, wetlands, ground water resources, wildlife habitats, and areas of
seismic and geological hazards.
Policy L-35: Ensure buildings, roads, and other features are located on less sensitive
portions of a site when sensitive areas are present.
Policy L-37: Land uses in areas subject to flooding, seismic, geologic, and coal mine
hazards should be designed to prevent property damage and environmental
degradation before, during, and after construction.
Policy L-56: Preserve natural landforms, vegetation, distinctive stands of trees, natural
slopes, and scenic areas that contribute to the City’s identity, preserve property values,
and visually define the community and neighborhoods.
17. Zoning Development Standard Compliance: The purpose of the Heavy Industrial Zone (IH) is to provide
areas for high-intensity industrial activities involving heavy fabrication, processing of raw materials, bulk
handling and storage, construction, and heavy transportation. Uses in this zone may require large
outdoor areas in which to conduct operations. Environmental impacts may be produced that affect off-
site areas, requiring isolation of the industrial activity from more sensitive land uses. Compatible uses
that directly serve the needs of other uses permitted within the district are also allowed. The proposal is
compliant with the following development standards, as outlined in RMC 4-2-130A, if all conditions of
approval are met:
Compliance IH Zone Develop Standards and Analysis
Use: Pursuant to RMC 4-2-060, sewage disposal and treatment plants require a Hearing
Examiner Conditional Use Permit in the IH zone. A sewage disposal and treatment plant
is a facility designed for the collection, removal, treatment, and disposal of waterborne
sewage.
Staff Comment: The applicant is requesting a Hearing Examiner Conditional Use Permit
to replace the South Plant’s Biogas Upgrading System (BUS) and heating system to
improve the beneficial use of digester gas at King County Wastewater Treatment
Division’s South Treatment Plant (STP) while also reliably supplying heat to meet process
and space heating demands. The project would improve the plant’s ability to produce
biomethane gas, which can be used as fuel, from the wastewater treatment process.
The South Plant Biogas and Heating Systems Project includes construction of a Heat and
Energy Recovery Building (HERB), a new thermal oxidizer, heating system improvements
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 7 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
within the existing Digester Equipment Building, and utility connections (Exhibit 6). Site
Plan Review is required for all development in the EA designation.
Lot Dimensions: The minimum lot size required in the IM zone is 35,000 sq. ft. There
are no minimum lot width or depth requirements.
Staff Comment: At this time, the applicant is not proposing to alter the existing
dimensions or area of the parcels. A future declaration of lot combination would comply
with the minimum lot size requirement of 35,000 square feet in the IM zone.
Compliant
if condition
of approval
is met
Setbacks: The minimum front yard setbacks are 20 feet along principal arterial streets
and 15 feet along other streets. The minimum secondary front yard setbacks are 20 feet
along principal arterial streets and 15 feet along other streets. There are no side or rear
yard setback requirements, except 50 feet if abutting a lot zoned residential and 20 feet
if a lot abuts a lot zoned CN, CV, CA, CD, CO, COR, or a lot with Public Facilities.
Staff Comment: The project improvements are located interior to the site, more than 20
feet from a public street. The proposed HERB building would be constructed over the
shared or group property line between parcel nos. 423049006 and 423049097;
therefore, staff is recommending King County complete a subsequent recording of a
declaration of lot combination or lot line adjustment such that new or existing structures
are not located over property lines. This shall be completed prior to building permit
issuance.
Building Standards: There are no maximum lot coverage requirements for buildings in
the IM zone. There are no maximum building height requirements in the IM zone.
Staff Comment: The applicant is proposing the construction of a new building west of
the existing digesters and Solids Motor Control Center (MCC) Building, in the northern
part of the plant property, to house the biogas upgrading system (BUS) and new boilers
for the plant’s heating system. The approximately 9,782 square foot HERB would be
located within an unused area, previously designated for plant expansion, currently
comprised of lawn overtopping a mound formed by previously-placed construction fill.
The anticipated maximum building height for the HERB is less than 30 feet. The site
slopes gradually to the east towards the existing Solids MCC Building and is maintained
as lawn grass over the mounded spoils (Exhibit 12). Previously placed spoils would be
removed and the existing slope would be re-graded as part of building construction. The
building would be primarily reinforced concrete, with an architectural finish similar to
existing buildings at the plant. Existing utility tunnels that run under the nearby Digester
Equipment Building would be extended to provide utilities to the new building.
The project would install a new thermal oxidizer equipment outside on a new concrete
pad (approximately 2,437 square feet) immediately south of the existing waste gas
burners and west of the proposed HERB. The anticipated maximum building height for
thermal oxidizer would consist primarily of an exhaust stack approximately 32 feet tall.
The thermal oxidizer would combust waste gas from the BUS. The primary feature of the
thermal oxidizer is an elevated stack alongside a horizontal oxidation chamber.
Landscaping: The City’s landscape regulations (RMC 4-4-070) require a 10-foot
landscape strip along all public street frontages. Additional minimum planting strip
widths between the curb and sidewalk are established according to the street
development standards of RMC 4-6-060. Street trees and, at a minimum, groundcover,
are to be located in this area when present. Spacing standards shall be as stipulated by
the Department of Community and Economic Development, provided there shall be a
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 8 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
minimum of one street tree planted per address. Any additional undeveloped right-of-
way areas shall be landscaped unless otherwise determined by the Administrator.
All parking lots shall have perimeter landscaping as follows:
Such landscaping shall be at least ten feet (10') in width as measured from the street
right-of-way. Standards for planting shall be as follows:
a. Trees shall be two inches (2") in diameter at breast height (dbh) for multi-family,
commercial, and industrial uses at an average minimum rate of one tree per thirty (30)
lineal feet of street frontage.
b. Shrubs at the minimum rate of one per twenty (20) square feet of landscaped area.
Up to fifty percent (50%) of shrubs may be deciduous.
c. Ground cover in sufficient quantities to provide at least ninety percent (90%)
coverage of the landscaped area within three (3) years of installation.
Surface parking lots with more than fourteen (14) stalls shall be landscaped as follows:
Surface parking lots with between 15 and 50 spaces shall provide 15 sf of landscaping
per parking space, 51 and 99 spaces shall provide 25 sf of landscaping per parking space,
and 100 or more spaces shall provide 35 sf of landscaping per parking space. Perimeter
parking lot landscaping shall be at least 10 feet in width, interior parking lot landscaped
areas shall have a minimum width of 5 feet.
Staff Comment: A conceptual landscape plan was submitted with the project application
(Exhibit 11). The conceptual landscape plan illustrates plant materials that would be
used to enhance the visual character of the building and site improvements. Together
the retained and new landscaping consists of a variety of vegetation along the property
edges and around the proposed and existing structures to help create human scale, add
visual interest along the building façades.
As there are no vehicular parking requirements for a wastewater treatment plant and
the proposed number of stall is less than 14, no interior parking lot landscaping would
be required.
The landscape plan proposes 14 new sweetgum trees, 29 new Douglas fir trees and a
meadow seed mix for disturbed areas. At the time of building permit submittal, a
detailed landscape plan would be submitted to, and approved by, the Current Planning
Project Manager prior to engineering permit approval. Staff recommends as a condition
of approval, that the applicant provide a final detailed landscape plan to be reviewed
and approved by the Current Planning Project Manager prior to construction permit
approval.
The applicant has requested a street modification from RMC 4-6-060F.2 to waive the
required frontage improvements along the public street frontage. See FOF 21, Street
Modification Analysis for more information.
Tree Retention: The City’s adopted Tree Retention and Land Clearing Regulations (4-4-
130) require the retention of 10 percent of trees in a commercial development.
Significant trees shall be retained in the following priority order:
Priority One: Landmark trees; significant trees that form a continuous canopy;
significant trees on slopes greater than twenty percent (20%); significant trees adjacent
to critical areas and their associated buffers; and significant trees over sixty feet (60') in
height or greater than eighteen inches ( 18") caliper.
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 9 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
Priority Two: Healthy tree groupings whose associated undergrowth can be preserved;
other significant native evergreen or deciduous trees; and other significant non- native
trees.
Priority Three: Alders and cottonwoods shall be retained when all other trees have been
evaluated for retention and are not able to be retained, unless the alders and/ or
cottonwoods are used as part of an approved enhancement project within a critical area
or its buffer.
Staff Comment: A Tree Report was prepared by Russell + Lambert Landscape
Architecture (dated February 15, 2018; Exhibit 10), including a Level 1 (planning level)
tree risk assessment for the 180 existing trees at the King County South Treatment Plant
near impacts associated with the proposed Biogas and Heating System Improvements,
and submitted with the land use application. Of the 180 assessed trees, 42 trees with a
Diameter at Breast Height (DBH) greater than 6” are proposed for removal. 39 trees
would be removed due to impacts of construction, three (3) trees would be removed due
to the poor condition of the trees which makes their location near construction and
proposed facilities high risk.
This project proposes to retain all trees for which the impacts of development would be
minimal or none with high visibility Tree Protection Fencing as shown on the Landscape
and Tree Retention Plans. The assessed trees in the Tree Report did not include any
Landmark (priority one) trees. The trees to be retained consisted of 138 priority two
trees.
The existing assessed trees were planted as part of previous development projects with
sufficient space between them to allow development of even canopies. The proposed
tree removals would likely not impact the health or durability of existing trees to remain.
The project proposes to retain seventy six (76%) of the existing significant trees onsite.
The significant trees range in size from 6 to 17 DBH. The proposed percentage of retained
trees exceeds the minimum required threshold to retain 10 percent (10%) of the
significant trees per RMC 4‐4-130H. No replacement trees would be required by Renton
Municipal Code (RMC). Nevertheless, 43 new trees would be planted onsite as part of
the improvement project.
Screening: All on-site surface mounted utility equipment shall be screened from public
view. Screening shall consist of equipment cabinets enclosing the utility equipment,
solid fencing or a wall of a height at least as high as the equipment it screens, or a
landscaped visual barrier allowing for reasonable access to equipment. Equipment
cabinets, fencing, and walls shall be made of materials and/or colors compatible with
building materials. All operating equipment located on the roof of any building shall be
enclosed so as to be screened from public view.
Staff Comment: Surface mounted equipment located in industrial developments that are
greater than one hundred feet (100') from residentially zoned property and/or public
streets are exempted from general screening requirements.
The rooftop equipment located on top of the HERB is proposed to be screened using a
parapet as shown on the architectural plans (Exhibits 7 and 8). In addition, the new
onsite buildings and equipment are located internal to the site and would not be visible
from the public view. The proposed landscaping plan also provides added screening
without impacting operation of the new building and equipment.
Refuse and Recycling: In office, educational and institutional developments, a minimum
of two (2) square feet per every one thousand (1,000) square feet of building gross floor
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 10 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
area shall be provided for recyclables deposit areas and a minimum of four (4) square
feet per one thousand (1,000) square feet of building gross floor area shall be provided
for refuse deposit areas. A total minimum area of one hundred (100) square feet shall
be provided for recycling and refuse deposit areas.
Staff Comment: Approximately 140 people currently work at STP. The new system
improvements would not result in any additional staff employment. No new refuse and
recycling is proposed for the King County South Plant Biogas and Heating Systems
Improvement Project. It is anticipated that the existing King County Treatment Plant
contains adequate refuse and recycling areas plant wide. According to the applicant, the
refuse and recycling materials at existing collections points are transported by janitorial
staff to the central facilities for refuse, general recycling, and metal recycling storage
unit pick-up. The majority of the material collected is generated by the spaces that are
occupied on a regular basis, namely the Administration Building, Division Control
Building, Santler Building, Maintenance Building, and Maintenance Annex. Accessible,
but unoccupied, spaces such as the utility tunnels, equipment rooms, and process
buildings contain collection points but because they are not occupied they do not
generally generate large quantities of refuse or recycled materials. The recycling storage
facility is located near the ETS Pump Building and is picked up weekly by SEADRUNAR
Recycling. Recyclable metals are stored in a dumpster near the Santler Building. Because
of the limited amount of material generated pick-up is on an as needed basis. The County
contracts with Seattle Iron and Metals for metal recycling. The refuse collection facility
is located near the Butler Building. King County contracts with Republic Services to
empty the 40 cubic yard dumpster bi-monthly.
Parking: Parking regulations are not specified in Renton Municipal Code for a
Wastewater Treatment Plant.
Standard parking stall dimensions are 9 feet by 20 feet, compact stall dimensions are 8
½ feet by 16 feet.
Staff Comment: The applicant is proposing up to 10 new uncovered parking stalls (seven
(7) on the north side of the new HERB and potentially a few more east of the thermal
oxidizer). The new stalls would comply with the parking dimension of the code. The
project would not eliminate any existing parking spaces. The existing and proposed
designated parking spaces appear to provide adequate parking for employees. No
additional onsite or off-site parking spaces is recommended.
Fences and Retaining Walls: A maximum of eight feet (8') anywhere on the lot provided
the fence, retaining wall or hedge does not stand in or in front of any required
landscaping or pose a traffic vision hazard.
There shall be a minimum three-foot (3') landscaped setback at the base of retaining
walls abutting public rights-of-way.
Staff Comment: The applicant not proposing fencing or retaining walls.
18. Critical Areas: Project sites which contain critical areas are required to comply with the Critical Areas
Regulations (RMC 4-3-050). The proposal is consistent with the Critical Areas Regulations, if all conditions
of approval are complied with:
Compliant
if condition
of
Geologically Hazardous Areas: Based upon the results of a geotechnical report and/or
independent review, conditions of approval for developments may include buffers
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 11 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
approval is
met
and/or setbacks from buffers. A standard 15-foot building setback is required for all
structures from Protected Slope areas.
A 50-foot buffer and 15-foot building setback are required from Very High Landslide
Hazard Areas.
Staff Comment: The site is underlain by rock consisting of the Renton Formation, which
is part of the Puget Rock Group. Fill at the project site consists of silty sand layer of
variable thickness. Given the nature of these sediments and their susceptibility to
liquefaction, the geotechnical engineer classified the site as “Site Class E” and the site-
class adjusted peak ground acceleration is 0.55g for the 2,475 -year return period and
0.36g for the 475-year return period.
Subsurface explorations, conducted by Shannon & Wilson, Inc. indicate the fill is present
to depths of about eight to 25 feet below ground surface at the location of the proposed
facility (Exhibit 14). Current plans call for the existing mound to be removed and the
proposed facility to be constructed on a relatively flat site. The new structure and
concrete pad would not be constructed on protected slopes. According to the
Geotechnical Report, slope instability due to ground shaking is low and not considered a
design issue for this project due to its distance to the fault zone (5 to 6 miles south to
southwest of the Seattle Fault Zone) and the relatively long repeat time for fault
movement. Therefore, the geotechnical engineer is recommending that the facility be
supported on a mat foundation. A mat foundation would reduce the potential for
differential settlement by evenly distributing structural loads. This foundation type offers
more structural continuity and flexural strength than a system of spread footings, and
would provide better stability on loose soils and soils that may liquefy. A mat foundation
would limit overall settlement at the proposed facility, including settlement brought on
by seismic conditions. A mat foundation may be designed for a maximum allowable
bearing pressure of 1,000 pounds per square foot, which is intended to not exceed the
preload stress that the bearing soils have experience in the past due to the mound of fill
that currently exists on the building site. The structural engineer would perform a finite
element modelling of the building and mat foundation.
Overall the submitted geotechnical report and addendums provide recommendations for
geologic hazards, seismic design considerations, foundations, lateral load resistance,
site grading and excavation, fill placement and compaction, wet weather earthwork, and
construction monitoring, drainage, pavements and coal mine hazards (Exhibits 14-16).
Staff recommends as a condition of approval that project construction be required to
comply with the recommendations found in the Geotechnical Engineering Study and
Addendums prepared by Shannon & Wilson, Inc. (dated January 6, 2017, March 16, 2017
and December 8, 2017) or an updated report(s) submitted at a later date.
According to City of Renton (COR) Maps, the site is located within a critical area
consisting of a moderate coal mine hazard because the site is within approximately 200
feet of a mapped historical coal mine consisting of a series of mine adits extending north
from the former mine entrance near the northeast corner of the Cogeneration Building
(Exhibit 16). The geotechnical engineer states that they are of the opinion that the mine
adits do not extend beneath the footprint of the proposed Heat and Energy Recovery
Building or the proposed thermal oxidizer as a result of advanced borings. The conclusion
of the Geotechnical Report Addendum indicated that there was no subsurface or surface
evidence of past mining activity at the proposed Facility site and there is low probability
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 12 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
that construction of the proposed Facility is at risk of coal mine hazards such as
subsidence.
Streams: The following buffer requirements are applicable to streams in accordance
with RMC 4-3-050G.2: Type F streams require a 115-foot buffer, Type Np streams
require a 75-foot buffer, and Type Ns streams require a 50-foot buffer. An additional 15-
foot building setback is required from the edge of all stream buffer areas.
Staff Comment: See FOF 22, Shoreline Exemption for more information related to
Springbrook Creek a Shoreline regulated under Shoreline Management Act.
Wetlands: The following buffer requirements are applicable to wetlands in accordance
with RMC 4-3-050G.2:
Wetland Category Buffer Width Structure
Setback
beyond
buffer
High
Habitat
Function
(8-9
points)
Moderate
Habitat
Function
(5-7
points)
Low
Habitat
Function
(3-4
points)
All Other
Scores
15 ft.
Category I – Bogs
& Natural
Heritage
Wetlands
200 ft.
Category I – All
Others
200 ft. 150 ft. 115 ft. 115 ft.
Category II 175 ft. 150 ft. 100 ft. n/a
Category III 125 ft. 100 ft. 75 ft. n/a
Category IV 50 ft. n/a
Staff Comment: A Wetland Assessment Report was prepared by ESA (dated January
2018) and submitted with the land use application. The entire site is located within
Water Resource Inventory Area (WRIA) 9, the Green – Duwamish Watershed and the
Lower Green River Subwaterdshed. ESA biologists identified one onsite wetland
(Wetland A) as a small palustrine scrub-shrub, depressional wetland located within a
swale at the south end of the grassy slope west of the proposed HERB building and one
off-site wetland (Wetland B) to the north. According to ESA, Wetland B appears to be
an enhanced or modified wetland feature associated with the constructed Waterworks
Gardens (see Figure 3, Wetland Locations of the Report). Wetland A is approximately
1,248 square feet in size and the primary source of hydrology was found to be
precipitation, although shallow groundwater source is also possible. This wetland
received and overall score of 15 points, which corresponds to a Category IV rating.
Wetland B consists of a series of depressions separated by a gravel pedestrian path,
located north of the South Plant fence. This wetland has a gentle slope to the east,
towards Spring Creek. The total wetland size was not estimated due to its off-site
location (only the southern boundary was delineated by ESA). Wetland B was rated as
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 13 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
a depressional wetland and received an overall score of 20 points, which corresponds
to a Category II rating with moderate habitat function. Wetland A requires a standard
buffer width of 50 feet and Wetland B requires a standard buffer width of 150 feet. A
condition of approval shall be installation of a wood, split-rail fence along the buffer of
Wetland A and a Native Growth Protection Easement (NGPE) shall be recorded over the
top of Wetland A and Wetland B and their associated buffers. The fence and the NGPE
shall be submitted with the construction permit application to be reviewed and
approved by the Current Planning Project Manager prior to construction permit
approval.
The proposed project would be located outside the standard 50-foot buffer for Wetland
A. According to RMC 4-3-050B.1.g, the City or Renton has the authority to not regulate
certain upland sites separated from critical area, if the site is separated from critical
areas by pre-existing, intervening, and lawfully created structures, roads, or other
substantial existing improvements. In this case, the project is separated from Wetland
B by the paved 20-foot wide north plant road with raised vertical curbs. In addition, an
approximately 8-foot wide paved path is located adjacent to the road. The substantive
width of the existing impervious road with vertical curbs, combined with the width of
the existing paved trail, serves as an effective barrier. These improvements completely
restrict and redirect the flow of ground and surface water, and otherwise impair delivery
of functions from upland sites located within the project area to Wetland B.
Upon final review the Wetland Assessment Report, staff concurs with the report findings
that the existing road creates a barrier and the buffer does not extend beyond the road
onto the project site. However, according to RMC 4-3-050B.1.g.b, for applications that
are subject to notices of application, the buffer determination or request for
determination shall be included with notice of application. Upon determination,
notification of parties of record, if any, shall be made. Therefore, staff intends to provide
onsite notification and notification mailings to parties of records disclosing this finding
following the public hearing date and land use decision date, in order to comply with
this notification requirement of the code.
According to the Report, stormwater from the plant road is collected and directed to
the Waterworks Gardens locate north of the plant. Current buffer functions performed
by the buffer area north of the existing plant road would not be altered by the proposed
project actions.
19. Conditional Use Analysis: The applicant is requesting a conditional use permit for the subject property
to replace South Plant’s Biogas Upgrading System and heating system. The project includes construction
of a Heat and Energy Recovery Building, a new thermal oxidizer, heating system improvements within
the existing Digester Equipment Building, and utility connections. The estimated project value is 5.5
million to complete the improvements. The proposal is compliant with the following conditional use
criteria, pursuant to RMC 4-9-030. Therefore, staff recommends approval of the requested Conditional
Use Permit.
Compliance Conditional Use Criteria and Analysis
Compliant
if condition
of approval
is met
a. Consistency with Plans and Regulations: The proposed use shall be compatible with
the general goals, objectives, policies and standards of the Comprehensive Plan, the
zoning regulations and any other plans, programs, maps or ordinances of the City of
Renton.
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 14 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
Staff Comment: The new and replaced improvements to King County’s Wastewater
Treatment Facility are consistent with the stated goals and policies of the City of Renton
Comprehensive Plan. See also FOF 16, Comprehensive Plan Analysis above.
The project would replace the existing South Treatment Plant (STP) systems to improve
the beneficial use of digester gas at STP while also reliably supplying heat to meet
process and space heating demands. As such, the project is directly serving the existing
wastewater treatment facility and is compatible with these purposes and goals. The
proposal is consistent with zoning regulations, development standards and all other
plans, programs, maps and ordinances of the City of Renton if all conditions are complied
with. See discussion above under FOF 17, Zoning Development Standard Compliance.
b. Appropriate Location: The proposed location shall not result in the detrimental
overconcentration of a particular use within the City or within the immediate area
of the proposed use. The proposed location shall be suited for the proposed use.
Staff Comment: The proposed location for the project would not result in detrimental
overconcentration of a particular use within the City or within the immediate area of the
proposed use. The project would serve to improve existing systems at the wastewater
treatment plant. Because the project requires byproduct from the wastewater treatment
facility, the location identified (vacant land located next to the existing wastewater
treatment plant) is suited for the proposed use.
c. Effect on Adjacent Properties: The proposed use at the proposed location shall not
result in substantial or undue adverse effects on adjacent property.
Staff Comment: The project is similar in scale to the existing wastewater treatment plant
improvements and would not result in substantial or undue adverse effects on adjacent
property. The project is located in the IH zone and is surrounded by King County owned
land associated with South Plant, and commercial and industrial uses. The City of Renton
anticipates that the surrounding area will continue to be used for commercial and light
industrial uses. The existing facility or the proposed addition to the facility is not
expected to be incompatible with existing or future land use plans of the area.
d. Compatibility: The proposed use shall be compatible with the scale and character
of the neighborhood.
Staff Comment: The proposed use would be compatible with the scale and character of
the neighborhood. The anticipated maximum building height is 30 feet. The exterior wall
treatment has been designed to match the other existing buildings onsite using similar
massing and materials.
e. Parking: Adequate parking is, or will be made, available.
Staff Comment: Adequate parking would be provided onsite. The project would not
result in any additional employees at the wastewater treatment facility. However, the
new facility would include seven new parking stalls (6 standard and 1 ADA) on the north
side of the building.
f. Traffic: The use shall ensure safe movement for vehicles and pedestrians and shall
mitigate potential effects on the surrounding area.
Staff Comment: A trip generation memorandum, prepared by Brown and Caldwell
(dated November 30, 2017; Exhibit 18) and submitted with the land use application,
estimated that the new facilities would not have any impact on the number of traffic
trips following construction. The project design included utilizing existing roads and
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
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Report of April 17, 2018 Page 15 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
driveways. It is anticipated that temporary impacts to traffic would result from the
proposed project during construction. According to the Memo, the project is generally
expected to require roughly 20 workers travelling to the site each weekday in personal
vehicles (on average). Truck traffic would almost be exclusively for delivery of materials
and equipment to the site and is expected to be on the order of 750 trips over the course
of the two-year construction period. The project currently does not include any removal
of excavation material from the site and as a result, truck traffic for hauling spoils off-
site is not expected by the project manager.
g. Noise, Light and Glare: Potential noise, light and glare impacts from the proposed
use shall be evaluated and mitigated.
Staff Comment: All impacts from noise generated by construction would be short-term,
temporary in nature and would take place during daylight hours. Construction noise
would likely exceed existing background noise levels. Noise levels would vary depending
on the specific equipment use for particular activities. Based on similar construction
projects, typical noise levels can be expected to range from 70 to 90 decibels (dBA)
measured at a distance of 50 feet from the source. Throughout the project construction,
short-term, intermittent construction related noise may include engine and mechanical
equipment noises associated with the use of heavy equipment such as bulldozers,
excavators, cranes, haul trucks, generators, chainsaws, and air compressors.
Construction-related noises would be limited to the City of Renton construction hours.
Work outside of normal construction hours is by City of Renton permission only. No
hauling or work is allowed on Sunday (Exhibit 23). Construction BMPs would be used to
minimize construction noise. See the Environmental Checklist for a list of BMPs (Exhibit
3). The noises generated, as a result of the proposed completed facilities, are not
anticipated to exceed City of Renton maximum permissible sound levels.
Temporary site lighting may be used at the beginning and end of work days during
construction when daylight hours are short. As a part of the completed project, the
entrances to HERB would be lit similar to existing site lighting at STP for safety and
security. All exterior lights would be focused or shielded as necessary to cast light only
in areas that require it and to minimize light spilling onto neighboring properties. No
glare impacts are anticipated by the project.
h. Landscaping: Landscaping shall be provided in all areas not occupied by buildings,
paving, or critical areas. Additional landscaping may be required to buffer adjacent
properties from potentially adverse effects of the proposed use.
Staff Comment: Landscaping would be provided in all disturbed areas not occupied by
buildings, paving, or critical areas. The proposed landscaping includes plantings
adjacent to the new building and new paved areas and responds to grading of the
eastern portion of the hill in the center of the project site to provide a level area for the
new building. The regraded hill would be stabilized with a selection of drought-tolerant
shrubs and groundcovers. Other areas of disturbance would be restored with a grass and
herbaceous plant seed mix similar to the existing groundcover found on the site.
Landscape plantings would be a combination of native Pacific Northwest species and
drought-resistant ornamentals. According to the applicant, plants would be selected for
adaptation to the different growing conditions present across the project site, including
shaded areas within and adjacent to existing stands of mature trees, sunny areas within
new landscape buffers and plantings adjacent to paved areas, and seasonally wet areas
within the stormwater treatment and infiltration areas. See also discussion under FOF
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 16 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
17, Zoning Development Standard Compliance: Landscaping, Tree Retention and
Screening.
20. Site Plan Review: Pursuant to RMC 4-9-200.B, Site Plan Review is required for all development within the
Employment Area (EA) zoning classification when it is not exempt from Environmental (SEPA) Review.
Given Site Plan applications are evaluated for compliance with the specific requirements of the RMC 4-
9-200E.3 the following table contains project elements intended to comply with level of detail needed
for Site Plan requests:
Compliance Site Plan Criteria and Analysis
Compliant if
Conditions
of Approval
are Met
a. Comprehensive Plan Compliance and consistency.
Staff Comment: See previous discussion under FOF 16, Comprehensive Plan Analysis.
Compliant if
Conditions
of Approval
are Met
b. Zoning Compliance and Consistency.
Staff Comment: See discussion above under FOF 17, Zoning Development Standard
Compliance.
N/A
c. Design Regulation Compliance and Consistency.
Staff Comment: The project location does not fall within one of the four (4) possible
design districts nor does RMC 4-2-115 Residential Design and Open Space Standards
apply, see applicability.
N/A d. Planned action ordinance and Development agreement Compliance and
Consistency.
Compliant if
Conditions
of Approval
are Met
e. Off Site Impacts.
Structures: Restricting overscale structures and overconcentration of development on
a particular portion of the site.
Staff Comment: The proposed development includes a 9,782 square foot HERB located
within an unused portion of the site. Spaces in the HERB would include gas compression
rooms, a boiler room, a control room, an electrical room, a bathroom, a gas analyzer
room, and space for heating, ventilation, and air conditioning (HVAC) equipment. The
project would also install a new thermal oxidizer equipment outside on a new concrete
pad (approximately 2,437 square feet). The proposed new structures are similar in scale
to the existing wastewater treatment plant improvements and the proposal does not
exceed development standards of the IH zone.
Circulation: Providing desirable transitions and linkages between uses, streets,
walkways and adjacent properties.
Staff Comment: The proposal utilizes existing interior linkages and public roads to get
to and circulate the South Plant. The existing circulation allows for safe ingress and
egress movements to and from the site. The primary access to the northern portion of
the Plant, where the project would be developed, is via SW 7th St. However, there are
additional driveways located off of Monster Rd SW, Longacres Dr SW and SW Grady
Way. No off-site improvements are proposed.
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 17 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
Loading and Storage Areas: Locating, designing and screening storage areas, utilities,
rooftop equipment, loading areas, and refuse and recyclables to minimize views from
surrounding properties.
Staff Comment: The proposal includes screening rooftop equipment with a parapet and
other site improvements with sufficient landscaping. The facility improvements are
located interior to the site and would not be visible from nearby non-King County
properties. See also discussion under FOF 17, Zoning Development Standard
Compliance: Screening and Refuse and Recycling.
Views: Recognizing the public benefit and desirability of maintaining visual accessibility
to attractive natural features.
Staff Comment: The proposed HERB includes a basement and the overall building height
would be less than 30 feet (Exhibits 7-9). The facility improvements would not impact
territorial views. Staff received no comments from adjacent properties regarding views.
Landscaping: Using landscaping to provide transitions between the development and
surrounding properties to reduce noise and glare, maintain privacy, and generally
enhance the appearance of the project.
Staff Comment: See discussion above under FOF 17, Zoning Development Standard
Compliance: Landscaping.
Lighting: Designing and/or placing exterior lighting and glazing in order to avoid
excessive brightness or glare to adjacent properties and streets.
Staff Comment: A lighting plan was not provided with the application; therefore staff
recommends that a lighting plan that adequately provides for public safety without
casting excessive glare on adjacent properties or critical areas be provided by the
applicant. Pedestrian scale and down-lighting shall be used in all cases to assure safe
pedestrian and vehicular movement. The lighting plan shall be submitted with the
construction permit application to be reviewed and approved by the Current Planning
Project Manager prior to construction permit approval.
f. On Site Impacts.
Structure Placement: Provisions for privacy and noise reduction by building placement,
spacing and orientation.
Staff Comment: The developed site conditions would be placed in areas that work in
conjunction with existing facilities on the South Plant. The applicant has submitted a
Construction Mitigation Plan (Exhibit 13) that provides measures to reduce construction
impacts such as noise, control of dust, traffic controls, etc. In addition, the project would
be required to comply with the City’s noise ordinance regarding construction hours.
Structure Scale: Consideration of the scale of proposed structures in relation to natural
characteristics, views and vistas, site amenities, sunlight, prevailing winds, and
pedestrian and vehicle needs.
Staff Comment: The proposed improvements would add approximately 34,617 square
feet of impervious surface area to the 191,824 square foot site. The proposed
development would be consistent with scale of the existing structures at the South
Plant. The new building and other site improvements are anticipated to provide for
access of sunlight, winds, and vehicle movement across the site.
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 18 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
Natural Features: Protection of the natural landscape by retaining existing vegetation
and soils, using topography to reduce undue cutting and filling, and limiting impervious
surfaces.
Staff Comment: The majority of the landscaping and improvements to the site would
be undisturbed as a result of the proposed development. Minor grading changes are
proposed to excavate the HERB to a depth of approximately 7 feet below ground
surface. The project proposes to move the spoils excavated from the HERB and
associated facilities (approximately 17,000 cubic yards) to a separate spoils placement
location, located approximately one-acre area south of the HERB and the existing
digesters within an open lawn area of the STP site. Spoils would be compacted and
seeded to match existing grades and vegetation type. The developer is anticipating the
following impact areas: HERB (11,862 SF), associated new driveway and parking area
(10,251 SF), concrete walkways and equipment pad (3,677 SF), asphalt walkway (407
SF), and thermal oxidizer pad (2,437 SF) located west of the West Spoils Area. New
landscaping is proposed on disturbed areas not occupied by buildings or impervious
areas.
Landscaping: Use of landscaping to soften the appearance of parking areas, to provide
shade and privacy where needed, to define and enhance open spaces, and generally to
enhance the appearance of the project. Landscaping also includes the design and
protection of planting areas so that they are less susceptible to damage from vehicles
or pedestrian movements.
Staff Comment: See discussion above under FOF 17, Zoning Development Standard
Compliance: Landscaping.
g. Access
Location and Consolidation: Providing access points on side streets or frontage streets
rather than directly onto arterial streets and consolidation of ingress and egress points
on the site and, when feasible, with adjacent properties.
Staff Comment: All vehicular access entering the property would be provided from
private internal streets within the South Plant. The proposed development is expected
to maintain the safety and efficiency of pedestrian, bicycle and vehicle circulation on
the site.
Internal Circulation: Promoting safety and efficiency of the internal circulation system,
including the location, design and dimensions of vehicular and pedestrian access
points, drives, parking, turnarounds, walkways, bikeways, and emergency access ways.
Staff Comment: See Location and Consolidation discussion above.
Loading and Delivery: Separating loading and delivery areas from parking and
pedestrian areas.
Staff Comment: The proposed facility improvements are not anticipating areas
necessary for loading and delivery. Following construction, the 50.2-acre facility would
contains adequate areas for both loading and delivery separate from parking and
pedestrian areas.
Transit and Bicycles: Providing transit, carpools and bicycle facilities and access.
Staff Comment: Per RMC 4-4-080F.11.a bicycle parking spaces are required at 10
percent (10%) of the number of required off-street parking spaces. The applicant is not
proposing new bicycle parking with the new building. As there are no vehicular parking
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
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Report of April 17, 2018 Page 19 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
requirements specified in RMC for a wastewater treatment plant, staff is not
recommending bicycle parking.
The facility is served by King County Metro, RapidRide F Line.
Pedestrians: Providing safe and attractive pedestrian connections between parking
areas, buildings, public sidewalks and adjacent properties.
Staff Comment: See discussion above under FOF 17, Zoning Development Standard
Compliance: Pedestrian Access.
h. Open Space: Incorporating open spaces to serve as distinctive project focal
points and to provide adequate areas for passive and active recreation by the
occupants/users of the site.
Staff Comment: The proposed project improvements still allow for adequate passive
and active recreation by the occupants/users of the site.
i. Views and Public Access: When possible, providing view corridors to shorelines and
Mt. Rainier, and incorporating public access to shorelines.
Staff Comment: The proposed structure would not block views. The public access
requirement is not applicable to the proposal.
j. Natural Systems: Arranging project elements to protect existing natural systems
where applicable.
Staff Comment: The proposed project elements, such as the temporary construction
access, would be designed to protect existing natural systems where applicable.
k. Services and Infrastructure: Making available public services and facilities to
accommodate the proposed use:
Police and Fire.
Staff Comment: Police and Fire Prevention staff indicated that sufficient resources exist
to furnish services to the proposed development; if the applicant provides Code required
improvements and fees.
Water and Sewer.
Staff Comment: The site is served by the City of Renton for all utilities. It has been
determined that the preliminary fire flow is 2,000 gpm. Water service for the existing
building shall be serviced by the existing private 12-inch water line that loops around
the property. The applicant must ensure that the water line that they connect to is the
correct line. Plans for the building permit would need to clearly show the connections
to the private lines for domestic water as well as the sprinkler system (if required).
These plans must also indicate the locations of the City of Renton 12-inch water
meter.
See also Advisory Notes to Applicant (Exhibit 23) for more water and sewer review
comments.
Drainage.
Staff Comment: A Technical Information Report (Full Drainage Review) was prepared
by Davido Consulting Group (DCG), Inc. (dated February 2018; Exhibit 17) and
submitted with the land use application.
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 20 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
The drainage report was completed in accordance with the standards found in the
2017 Renton Surface Water Design Manual (RSWDM) and all nine (9) core and six (6)
special requirements were addressed. Based on the City’s flow control map, the site
falls within the Peak Rate Flow Control Standard area matching Existing Site
Conditions and is within the Black River Drainage Basin. The submitted geotechnical
report and two (2) addendums provided information on the water table and soil
permeability with recommendations of appropriate flow control BMP options with
typical designs for the site from the geotechnical engineer. There were three (3) PIT
tests taken to measure the permeability of the soil and the infiltration rates were
measured at approximately 0.02 inch/hour (without correction factors). The applicant
is proposing to do a Treatment Trade as described in section 1.2.8.2C that meets the
City of Renton requirements as outlined in the Surface Water design manual. For City
approval, the applicant must show the 2,935 SF area of the offsite roadway that
would flow onsite and be collected and treated to compensate for the 2,844 SF of
onsite area not collected and treated. A Civil Construction Plan and Permit would be
required for the storm system improvements proposed by the project.
See Advisory Notes to Applicant for more storm drainage comments (Exhibit 23).
Transportation.
Staff Comment: A trip generation memorandum, prepared by Brown and Caldwell
(dated November 30, 2017; Exhibit 18) and submitted with the land use application.
See discussion above under FOF 19, Conditional Use Analysis: Traffic.
Under building permits B16006588 and B16006723, King County submitted a street
modification request that was approved by the City of Renton in 2017 for the previous
project within the King County Waste Water treatment facility (Exhibit 23). See also FOF
21, Street Modification Analysis for more information.
l. Phasing: The applicant is proposing to phase the construction project. The
project construction is scheduled to begin in mid-2019 and the new biogas and heating
system is scheduled to be operational by the end of 2021. A minor element of the
project, the installation of a third heating boiler, would occur in a future construction
contract with a schedule yet to be determined.
m. Stormwater: Providing optimal locations of stormwater infiltrating low impact
development facilities. Avoiding placement of buildings or impervious areas on soils
with infiltration capability to the maximum extent practicable.
Staff Comment: See Drainage discussion above.
21. Street Modification Analysis: Pursuant to Renton Municipal Code (RMC) 4-9-250D, the applicant is
requesting Modification from RMC 4-6-060F.2, Minimum Design Standards for Public Streets and Alleys,
to waive the required street improvements on Monster Rd SW (Exhibit 22). Improvements would include
17 feet of right-of-way dedication, 11-foot center turn lane, 8-foot wide sidewalk, 8-foot wide planter
strip, 0.5-foot curb and gutter, 10-foot wide travel lane, 5-foot wide bike lane, and 8-foot wide parking
lane on both sides of the road. RMC 4-9-250D allows for a modification of the required street
improvements subject to six (6) decision criteria. Therefore, staff is recommending approval of the
requested modification, if all conditions of approval are met, as noted below:
Compliance Street and Driveway Modification Criteria and Analysis
a. Substantially implements the policy direction of the policies and objectives of the
Comprehensive Plan Land Use Element and the Community Design Element and the
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 21 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
proposed modification is the minimum adjustment necessary to implement these
policies and objectives.
Staff Comment: The Community Design Element has applicable policies listed under a
separate section labeled Promoting a Safe, Healthy, and Attractive Community. These
policies address walkable neighborhoods, safety, and shared uses. The intent of the
policies are to promote new development with walkable places that support grid and
flexible grid street and pathway patterns, and are visually attractive, safe, and healthy
environments. The requested street modification is consistent with these policy
guidelines.
b. Will meet the objectives and safety, function, appearance, environmental
protection and maintainability intended by the Code requirements, based upon
sound engineering judgment.
Staff Comment: The City’s Public Works Transportation Department and Community and
Economic Development have reviewed Monster Rd SW. Much of the property frontage
along Monster Rd SW is located within a regulated or steep slope making additional
frontage improvements infeasible. In areas where there is no regulated steep slope,
there is an existing curb/gutter and five foot wide sidewalk providing pedestrian
connectivity which meets the intent of the City’s Comprehensive Plan and Municipal
Code. In addition, in order to construct complete streets along Monster Rd SW the
roadway would need to be shifted west within the right-of-way, which would impact the
properties on the west side of the right-of-way, or large walls would need to be
constructed on the east side of the roadway reducing the existing vegetation along the
roadway.
Moreover, there is an existing five foot wide sidewalk along the east side of Monster Rd
SW. In areas along Monster Rd SW, where there is no sidewalk adjacent to the regulated
steep slope, the pedestrian needs are met by an existing public 10-foot wide asphalt
pedestrian path that traverses the steep slope along Monster Rd SW.
c. Will not be injurious to other property(ies) in the vicinity.
Staff Comment: Existing pavement width and existing pedestrian sidewalks and
pathway provide for safe vehicular and pedestrian travel. There are no identified adverse
impacts to other properties from the requested modification.
d. Conforms to the intent and purpose of the Code.
Staff Comment: This modification accounts for pedestrian circulation around the
perimeter of the site and conforms to the intent and purpose of the code.
e. Can be shown to be justified and required for the use and situation intended; and
Staff Comment: See comments above under criterion ‘b’.
f. Will not create adverse impacts to other property(ies) in the vicinity.
Staff Comment: The modification would not create adverse impacts to other properties
in the vicinity. See also comments above under criterion ‘c’.
22. Shoreline Exemption: Springbrook Creek flows along the east perimeter of the plant site before joining
the Black River to the north. A Standard Stream Study was prepared by Environmental Science Associates
(ESA), (dated January 5, 2018; Exhibit 20) and submitted with the land use application.
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 22 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
The applicant is proposing a temporary construction entrance within a portion of the shoreline
jurisdiction of Springbrook Creek. According to the Standard Stream Study, Springbrook Creek was
extensively modified and straightened for agricultural drainage in the 1920s by King County Drainage
District No. 1. The channel area abutting the project was improved in the 1980s and 1990s for flood
control by the City of Renton in cooperation with the Natural Resource Conservation Service. The stream
is constrained and channelized throughout the shoreline. Levees that define the streambank limit the
width of the riparian corridor.
Springbrook Creek is classified as Shoreline High Intensity under the City’s Shoreline Management
Program. Existing vegetation along the shoreline is typical native riparian forest species and includes a
mixture of red alder, willow species, Himalayan blackberry and sedges (Carex spp.) along with some
ornamental trees. Conifers are almost exclusively absent, and in those areas where shade is absent, reed
canary grass is abundant. The Springbrook Creek vegetated riparian area is separated from the project
site by the plant driveway (Road “N”). Chinook, Chum, Coho, Steelhead Trout, and Cutthroat Trout are
found in Springbrook Creek, utilizing the habitat primarily for migration. According to Washington
Department of Fish and Wildlife (WDFW), SalmonScape fish distribution data, fall Chinook, fall chum, and
winter steelhead are present and coho rear in the creek. Under Washington State Water Quality
Standards, Springbrook Creek is categorized as “Spawning Rearing and Migration Habitat” for aquatic life
use and “Primary Contact” for recreational use. The Creek is on Washington Department of Ecology’s
303(d) list for violation of dissolved oxygen and fecal coliform bacteria standards (Category 5).
According to the Report, construction and use of the temporary construction entrance would result in no
net loss of ecological functions or processes. Specifically, by avoiding and minimizing impacts to shoreline
resources. Existing vegetation on the proposed temporary construction entrance site consists of
herbaceous species (grasses). The structural and species diversity was identified as low. No trees would
be removed within the shoreline, and there would be no impacts to the existing vegetated riparian buffer.
Minor grading would be required for construction of the temporary construction entrance. As part of the
civil construction plans, the applicant would develop and implement a temporary erosion and sediment
control plan during construction and operation of the temporary construction entrance to ensure no
changes in turbidity or water quality. The site of the proposed temporary construction entrance is located
in an area that was filled, to a depth of 25 feet with silty sand and gravel, and graded as part of the
previous STP construction projects. There are no wetlands, water bodies or steep slopes present within
the proposed temporary construction access.
Following construction, the temporary construction entrance (approximately 290 cubic yards of soil and
120 yards of quarry spalls) would be removed and the area be regraded to existing grades and
revegetated consistent with previously existing vegetation. No permanent changes are proposed to the
existing onsite drainage conditions. Project effects in relation to shoreline processes and ecological
functions outlined in RMC 4-8-090 are provided in Table 1 of the Report, as shown in the table, the project
would have neutral effects on each process or function.
Work will be restricted to temporary grading for installation of the temporary construction entrance.
Construction and use of the temporary construction entrance would occur within a portion of the
shoreline jurisdiction of Springbrook Creek. The 4,375 square foot (175-foot x 25-foot) temporary
stabilized construction entrance would extend from the existing South Treatment Plant (STP) road west
of Springbrook Creek to provide access to the spoils placement location within an open lawn area of the
STP site further to the west. The construction entrance would consist of 4-inch to 8-inch quarry spalls
that are 12 inches thick and underlain by geotextile. Hog fuel may be substituted for or combined with
quarry spalls. Fencing would be installed to restrict traffic to the construction entrance. If the entrance
does not prevent sediment from being tracked onto pavement, alternative measures will be used to keep
the streets free of sediment (e.g., street sweeping, increase in dimensions of the entrance, installation of
a wheel wash). If washing is done, it would occur on an area covered with crushed rock and washed water
would drain into a sediment trap or pond. Following grading activities on the spoils placement site, the
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 23 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
temporary stabilized construction entrance would be removed, grades would be restored to their
preconstruction condition, and the area would be permanently stabilized with mulch followed by seeding
per Sections C.3.2 and C.3.10, respectively, of the 2017 City of Renton Surface Water Design Manual.
Total cost of the activity is $6,900.00, which is less than the current Washington Department of Ecology
shoreline exemption threshold of $7,047.00.
23. Availability and Impact on Public Services:
Compliance Availability and Impact on Public Services Analysis
Police and Fire: Police and Fire Prevention staff indicates that sufficient resources exist
to furnish services to the proposed development; subject to the condition that the
applicant provides Code required improvements and fees. No fire impact fees are
applicable for this project.
Schools: The South Plant Biogas and Heating Systems Improvements Project would not
add new students to the Renton School District.
Parks: No park impact fees would be required for the South Plant Biogas and Heating
Systems Improvements Project.
Storm Water: An adequate drainage system shall be provided for the proper drainage
of all surface water.
Staff Comment: See discussion above under FOF 20, Site Plan Review: Drainage.
Water: See discussion above under FOF 20, Site Plan Review: Water and Sewer.
Sanitary Sewer: See discussion above under FOF 20, Site Plan Review: Water and Sewer.
I. CONCLUSIONS:
1. The subject site is located in the Employment Area (EA) Comprehensive Plan designation and complies
with the goals and policies established with this designation, see FOF 16.
2. The subject site is located in the Heavy Industrial (IH) zoning designation and complies with the zoning
and development standards established with this designation provided the applicant complies with City
Code and conditions of approval, see FOF 17.
3. The proposed South Plant Biogas and Heating Systems Improvements Project complies with the Critical
Areas Regulations provided the applicant complies with City Code and conditions of approval, see FOF
18.
4. The proposed South Plant Biogas and Heating Systems Improvements Project complies with the
Conditional Use Permit criteria as established by City Code and state law provided all advisory notes
and conditions are complied with, see FOF 19.
5. The proposed South Plant Biogas and Heating Systems Improvements Project complies with the Site
Plan Review criteria as established by City Code and state law provided all advisory notes and
conditions are complied with, see FOF 20.
6. The proposed South Plant Biogas and Heating Systems Improvements Project complies with the six (6)
decision criteria of street improvements per RMC 4-9-250D, to approve a street modification, see FOF
21.
City of Renton Department of Community & Economic Development Hearing Examiner Recommendation
KING COUNTY SOUTH PLANT BIOGAS AND HEATING SYSTEMS IMPROVEMENTS PROJECT LUA18-000188, SA-A, CU-H, SME, MOD
Report of April 17, 2018 Page 24 of 24
HEX Report South Plant Biogas and Heating Systems Improvements Project
7. The proposed South Plant Biogas and Heating Systems Improvements Project temporary construction
entrance complies with the current Washington Department of Ecology shoreline exemption threshold,
see FOF 22.
8. There are adequate public services and facilities to accommodate the proposed development, see FOF
23.
9. The proposed South Plant Biogas and Heating Systems Improvements would improve the plant’s
heating systems to more reliably meet process and space heating demands.
J. RECOMMENDATION:
Staff recommends approval of the South Plant Biogas and Heating Systems Improvements Project, File No.
LUA18-000188, as depicted in Exhibit 6, subject to the following conditions:
1. The applicant, King County Wastewater Treatment Division's South Treatment Plant (STP), shall complete
a recording of a declaration of lot combination or lot line adjustment prior to building permit issuance.
2. The applicant shall provide a final detailed landscape plan for review and approval by the Current
Planning Project Manager prior to construction permit approval.
3. Project construction shall be required to comply with the recommendations found in the Geotechnical
Engineering Study and Addendums prepared by Shannon & Wilson, Inc. (dated January 6, 2017, March
16, 2017 and December 8, 2017) or an updated report(s) submitted at a later date.
4. A wood, split-rail fence shall be installed along the buffer of Wetland A and a Native Growth Protection
Easement (NGPE) shall be recorded over the top of Wetland A and Wetland B and their associated
buffers. The fence and the NGPE shall be submitted with the construction permit application to be
reviewed and approved by the Current Planning Project Manager prior to construction permit approval.
5. The applicant shall provide a lighting plan that adequately provides for public safety without casting
excessive glare on adjacent properties or critical areas. Pedestrian scale and down-lighting shall be used
in all cases to assure safe pedestrian and vehicular movement. The lighting plan shall be submitted with
the construction permit application to be reviewed and approved by the Current Planning Project
Manager prior to construction permit approval.
CITY OF RENTON
DEPARTMENT OF COMMUNITY AND
ECONOMIC DEVELOPMENT
REPORT TO THE HEARING EXAMINER, EXHIBITS
Project Name:
King County South Plant Biogas and Heating
Systems Improvements Project
Project and Land Use File Numbers:
PR16-000503 / LUA18-000188, SA-A, CU-H, SME,
MOD
Date of Hearing
April 17, 2018
Staff Contact
Clark H. Close
Senior Planner
Project Contact
Chris Dew, King County
Wastewater Treatment
Division, 201 S Jackson St,
Seattle, WA 98104
Project Location
1200 Monster Rd SW,
Renton, WA 98057
The following exhibits were entered into the record:
Exhibit 1: Hearing Examiner Staff Recommendation (dated April 17, 2018)
Exhibit 2: Environmental (SEPA) Determination of Nonsignificance (DNS) (dated March
5, 2018)
Exhibit 3: Environmental Checklist
Exhibit 4: Vicinity Map
Exhibit 5: Neighborhood Detail Map
Exhibit 6: Site Plan
Exhibit 7: Conceptual Color Building Renderings
Exhibit 8: Architectural Exterior Elevations
Exhibit 9: Floor Plans
Exhibit 10: Tree Report, prepared by Russell Lambert Landscape Architecture, dated
February 15, 2018
Exhibit 11: Landscape and Tree Retention Plans
Exhibit 12: Civil Construction Plans
Exhibit 13: Construction Mitigation Description
Exhibit 14: Geotechnical Engineering Report, prepared by Shannon & Wilson, Inc. dated
January 6, 2017
Exhibit 15: Addendum to Geotechnical Engineering Report, prepared by Shannon &
Wilson, Inc. dated March 16, 2017
Exhibit 16: Geotechnical Engineering Report Addendum, prepared by Shannon & Wilson,
Inc. dated December 8, 2017
Exhibit 17: Technical Information Report (Full Drainage Review), prepared by Davido
Consulting Group (DCG), Inc., dated February 2018
Exhibit 18: Trip Generation Memorandum, prepared by Brown and Caldwell, dated
November 30, 2017
Page 2
Exhibit 19: Wetland Assessment Report, prepared by ESA, dated January 2018
Exhibit 20: Standard Stream Study, prepared by ESA, dated January 5, 2018
Exhibit 21: Temporary Construction Entrance Site Plan
Exhibit 22: Street Modification Request
Exhibit 23: Advisory Notes to Applicant
tQ King County
Department of Natural Resources and Parks • Wastewater Treatment Division
Environmental Services • 201 South Jackson Street, MS KSC-NR-0505
Seattle, WA 98104-3855
DETERMINATION OF NONSIGNIFICANCE
TITLE OF PROPOSAL: South Plant Biogas and Heating Systems Improvements
DESCRIPTION OF PROPOSAL: The King County Wastewater Treatment Division (KCWTD) proposes to replace the existing biogas
upgrading system (BUS) and heating systems at KCWTD's South Treatment Plant (STP) in Renton, WA. The project will improve the
plant's ability to produce biomethane gas, which can be used as fuel, from the wastewater treatment process. The project will also improve
the plant's heating systems to mot'e reliably meet process and space heating demands. The project includes construction of the Heat and
Energy Recovery Building (HERB), a new thermal oxidizer, heating system improvements within the existing Digester Equipment
Building, stormwater management facilities, and utility connections. Project construction is scheduled to begin in mid-2019, and the new
biogas and heating system is scheduled to be operational by the end of 2021.
LOCATION OF PROPOSAL, INCLUDING STREET ADDRESS, IF ANY: The proposed project is located in Renton W A, at 1200
Monster Road SW. The project will occupy King County Parcel Numbers 2423049097 and 2423049006, which are located in NE Quarter-
Section, Section 24, Township 23 North, Range 9 East.
SEP A Responsible Official:
Position/Title:
Address:
Proponent and Lead Agency:
Contact Person:
Issue Date:
Mark Isaacson
Director, King County Wastewater Treatment Division
King County ID1epartment ofNatural Resources and Parks
Wastewater TUatment Division
Jacob Sheppard, Water Quality Planner
King County Wastewater Treatment Division
201 South Jackson Street, MS KSC-NR-0505
Seattle, WA 98104
phone: (206) 477-5395; e-mail: jacob.sheppard@kiligcounty.gov
March 9, 2018
The State Environmental Policy Act (SEP A) lead agency for this proposal has determined that it does not have a probable significant
adverse impact on the environment. An environmental impact statement is not required under RCW 43.21C.030(2)(c). This decision was
made after review of a completed enviromnental checklist, the environmental reports listed in Section A.8 of the environmental checklist,
and other information on file with the lead agency. This infmmation is available to the public on request.
[g) This Determination ofNonsignificance (DNS) is issued under WAC 197-11-340 (2); the lead agency will not act on this proposal for
14 days from the issue date. Comments must be submitted by March 23, 2018. Submit comments to Katherine Fischer, Supervisor,
Environmental Services, King County Wastewater Treatment Division, 201 South Jackson Street, MS KSC-NR-0505, Seattle, WA 98104-
3855. Contact Jacob Sheppard, Water Quality Planner, at (206) 477-5395 or jacob.sheppard@kingcounty.gov for questions or information
on how to submit comments electronically.
[g) The King County Wastewater Treatment Division recently submitted a conditional use permit application for this project to the City of
Renton. Therefore, there is no administrative appeal of this DNS pursuant to RCW 43.21 C.075, WAC 197-11-680, KCC 20.44.120, and
King County Public Rule 7-4-1. The public rule may be viewed at http://www.kingcounty.gov/about/policies/rules/utilities/put741pr.aspx
or contact Jacob Sheppard, Water Quality Plam1er, at (206) 477-5395 or jacob.sheppard@kingcounty.gov to obtain a copy of the rule.
[Statutory authority: RCW 43.21 C.llO. 84-05-020 (Order DE 83-39), § 197-11-970, filed 2/10/84, effective 4/4/84.]
ENVIRONMENTAL CHECKLIST
A. BACKGROUND
1. Name of proposed project, if applicable:
South Plant Biogas and Heating Systems Improvements
2. Name of applicant:
King County Department of Natural Resources and Parks
Wastewater Treatment Division
3. Address and phone number of applicant and contact person:
King County Department of Natural Resources and Parks
Wastewater Treatment Division
Environmental Services Unit
KSC-NR-0505
201 S. Jackson Street
Seattle, WA 98104
CONTACT: Jacob Sheppard, Environmental Planner
Phone: (206) 477-5395
Email: jacob.sheppard@kingcounty.gov
4. Date checklist prepared:
February 9, 2018
5. Agency requesting checklist:
King County Department of Natural Resources and Parks
Wastewater Treatment Division
6. Proposed timing or schedule (including phasing, if applicable):
Project construction is scheduled to begin in mid-2019. The new biogas and heating
system is scheduled to be operational by the end of 2021. A minor element of the
project, the installation of a third heating boiler, will occur in a future construction
contract with a schedule yet to be determined.
7. Do you have any plans for future additions, expansions, or further activity
related to or connected with this proposal? If yes, explain.
No
2/9/2018 1
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DUVALL01OREGON80395PASCO129039512234SCALE IN MILESLOCATION MAPALBERTACOLUMBIASPOKANE97395ANATNOM2020BRITISH40 6080PROJECTLOCATIONPROJECT LOCATION1200 MONSTER RD SW, RENTON, WA 98057SW 16TH ST (S 153RD ST)INTERSTATE HWY 405WS DR RETSNOMSPRINGBROOK CREEKOAKESDALE AVE SW SW GRADY WAYSCALE: 1"=100'PLANT GRID NORTHLAMBERT NORTH16°20'58"PUBLICINFORMATIONSIGNLOCATIONSITE MAPSW 7TH STREETPROPERTYLINE46506PROPOSEDTHERMAL OXIDIZERSPOILSPLACEMENTPROPOSED HEAT & ENERGYRECOVERY BUILDING
^
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South Treatment Plant
Neighborhood Detail Map
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Proposed ThermalOxidizer
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0 200
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Figure 1
South Plant Biogas and Heat Systems Improvements
Neighborhood Detail Map
N Project Site
12345DESIGNED/DRAWN:PROJECT ENGINEER:PROJECT ACCEPTANCE:DESIGN APPROVAL:CONTRACT NO:DRAWING NO:PROJECT FILE NO:SCALE:FACILITY NUMBER:DEPARTMENT OF NATURAL RESOURCES & PARKSWASTEWATER TREATMENT DIVISIONDATE:SHT NO / TOTALREVNO:BORDER FILE EDITION: KCWTD-2015R0-Dsize-TB-Border12345EFGHBCDACHECKED:REFERENCE1"0P:\Clients\king county\B C\on-call bc\south plant wwtp\_CAD\02-SHEETS\G-GENERAL\224-1123626G0000017.dwg | Layout: G0000017 OVERALL SITE PLANPLOTTED: Dec 22, 2017-06:44:53pm By dsaarenasXREFS: KCWTD-2015R0-Dsize-TB-Border.dwg; 224-1123626ExistSurv.dwg; 224-1123626CivilExistingBasemap.dwg; 224-1123626CivilSitePlan_C3D.dwg; 224-1123626CivilPipe_C3D.dwg; WWTP Key Plan.dwg; _WASHINGTON-SEAL_ED.dwg; 224-1123626CivilSiteIndex.dwg; 224-1123626CivilLimits.dwg; 224-1123626CivilWipeout.dwgIMAGES:SOUTH TREATMENT PLANTBIOGAS AND HEAT SYSTEMS IMPROVEMENTSJAN 201815-xxxxxxxNO REVISION DESCRIPTION BY APVD DATEEFGHBCDAS. HildrethPRELIMINARY ISSUE DRAWING60% REVIEWJANUARY 2018G0000017D. SaarenasB. IddinsE. Davido1" = 80'0E. DavidoSCALE: 1" = 80'OVERALL SITE PLANAREA SHOWN ON THIS PLANWWTP KEY PLANNO SCALE33723OAKESDALEAVE SWSW 7T
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T LIMITS OFCONSTRUCTION50FT WETLANDBUFFERAPPROX 200-FT SHORELINEJURISDICTION PER COR GISMAPPING100-YR FLOODPLAIN PERCOR GIS MAPPINGEXISTING SPOILSLOCATIONEX FIREHYDRANTEX FIREHYDRANTEX FIREHYDRANTAPPROXIMATE OHWM(NOT SURVEYED)EXISTING DIGESTERFACILITYSPRINGBROOKCREEKPROPOSEDTHERMAL OXIDIZERPROPOSED HEAT & ENERGYRECOVERY BUILDINGPROPOSEDSPOILS LOCATION
Tree Report Page 1 of 6 King County South Treatment Plant
Tree Report
King County South Treatment Plant Biogas and Heat Systems Improvements
February 15, 2018
Prepared by: Mary Ellen Russell
Landscape Architect, Washington no. 1149, 2009
Tree Risk Assessment Qualification, International Society of Arboriculture, 2015
On November 15, 2017, I completed a level 1 (planning level) tree risk assessment for 180 existing trees
at the King County South Treatment Plant near impacts associated with proposed Biogas and Heat
System Improvements. This report details the results of those tree assessments. This report is written in
accordance with the requirements of Renton Municipal Code section 4‐4‐130, Tree Retention and Land
Clearing Regulations. Locations of assessed trees are shown on the Landscape and Tree Retention Plan.
A summary and details of the assessment are shown in the table below.
Of the 180 assessed trees, 42 trees with a Diameter at Breast Height (DBH) greater than 6” are proposed
for removal. 39 trees will be removed due to impacts of construction, 3 trees will be removed due to the
poor condition of the trees which makes their location near construction and proposed facilities high
risk.
All trees proposed to be retained will be protected with high visibility Tree Protection Fencing as shown
on the Landscape and Tree Retention Plans. Wherever possible, tree protection fencing shall be located
10’ from the base of the trunk or at the dripline, whichever is greater, to protect the critical root zone.
For trees to remain, no impacts shall be located closer than 5’ to be base of the trunk or in more than
25% of the critical root zone.
This project proposes to retain all trees for which the impacts of development will be minimal or none.
The tree retention priorities specified in RMC 4‐4‐130H.1.b have been considered as part of this report.
The assessed trees in this report do not include any Landmark (priority one) trees. The trees to be
retained consist of 138 priority two trees.
The existing assessed trees were planted as part of previous development projects with sufficient space
between them to allow development of even canopies. The proposed tree removals will likely not
impact the health or durability of existing trees to remain. The project proposes to retain 76% of the
existing significant trees on site. This is well above the minimum required threshold of 10% per RMC 4‐4‐
130H. No replacement trees are required.
7901 Woodlawn Ave NE, Ste 202
Seattle, WA 98115
206.898.6312
maryellen@russell‐lambert.com
EXISTING
MEADOW AREA
TREE RETENTION LEGEND
TREE RETENTION NOTES:
1.WHEREVER FEASIBLE, TREE PROTECTION FENCING SHALL BE LOCATED A
MINIMUM OF 10' FROM THE TRUNK OR AT THE DRIP LINE, WHICHEVER IS
GREATER. WHERE SITE IMPACTS OCCUR LESS THAN 10' FROM THE TREE
TRUNK, TREE PROTECTION FENCING SHALL BE LOCATED A MINIMUM OF 5'
FROM THE TRUNK. TREES THAT WILL BE IMPACTED CLOSER THAN 5' FROM
THE TRUNK, OR TREES WHO WILL BE IMPACTED IN MORE THAN 25% OF THE
CRITICAL ROOT ZONE SHALL BE REMOVED.
EXISTING DECIDUOUS TREE TO REMAIN
EXISTING EVERGREEN TREE TO REMAIN
EXISTING DECIDUOUS TREE TO BE REMOVED
EXISTING EVERGREEN TREE TO BE REMOVED
EXISTING DECIDUOUS TREE LESS THAN 6" DBH TO REMAIN
EXISTING EVERGREEN TREE LESS THAN 6" DBH TO REMAIN
EXISTING DECIDUOUS TREE LESS THAN 6" DBH TO BE REMOVED
EXISTING EVERGREEN TREE LESS THAN 6" DBH TO BE REMOVED
TREE PROTECTION FENCING
AREA SHOWN ON THIS PLAN
WWTP KEY PLAN
NO SCALE
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DESIGNED/DRAWN:
PROJECT ENGINEER:
PROJECT ACCEPTANCE:
DESIGN APPROVAL:
CONTRACT NO:
DRAWING NO:
PROJECT FILE NO:SCALE:
FACILITY NUMBER:
DEPARTMENT OF NATURAL RESOURCES & PARKS
WASTEWATER TREATMENT DIVISION
DATE:
SHT NO / TOTAL REV
NO:BORDER FILE EDITION: KCWTD-2015R0-Dsize-TB-Border1
2
3
4
5
E F G HBCDA
CHECKED:REFERENCE1"0P:\King County\148642 KC SP Biogas and Heat Sys Imp\_CAD\02-SHEETS\L-LANDSCAPE\Newer 60-pct Archive\224-1123626L2240101.dwg | Layout: L2240101 LANDSCAPE IRRIGATION AND TREE RETENTION PLAN AREA 15PLOTTED: Feb 16, 2018-03:15:53pm By SPlancicXREFS: KCWTD-2015R0-Dsize-TB-Border.dwg; 224-1123626ExistSurv.dwg; 224-1123626CivilExistingBasemap.dwg; WWTP Key Plan.dwg; 224-1123626CivilSitePlan.dwg; 224-1123626LandscapeSitePlan.dwg; 224-1123626ExistTreeReport.dwgIMAGES:SOUTH TREATMENT PLANT
BIOGAS AND HEAT SYSTEMS IMPROVEMENTS
FEB 2018
15-xxxxxxx
NO REVISION DESCRIPTION BY APVD DATE
E F G HBCDA
S. Hildreth
PRELIMINARY ISSUE DRAWING
INFORMATION ONLY
90% REVIEW
FEBRUARY 2018
I. McKelvey
C01248C18
LANDSCAPE AND TREE RETENTION PLAN
AREA 15 L2240101
R. Lambert
R. Lambert 1" = 20'
0
R. Bard
MATCH LINE - SEE DWG L2240102
MATCH LINE - SEE DWG L2240105STATE OF
WASHINGTON
REGISTERED
LANDSCAPE ARCHITECT
RYAN D. LAMBERT
CERTIFICATE NO. 1190
AREA SHOWN ON THIS PLANWWTP KEY PLANNO SCALE12345DESIGNED/DRAWN:PROJECT ENGINEER:PROJECT ACCEPTANCE:DESIGN APPROVAL:CONTRACT NO:DRAWING NO:PROJECT FILE NO:SCALE:FACILITY NUMBER:DEPARTMENT OF NATURAL RESOURCES & PARKSWASTEWATER TREATMENT DIVISIONDATE:SHT NO / TOTALREVNO:BORDER FILE EDITION: KCWTD-2015R0-Dsize-TB-Border12345EFGHBCDACHECKED:REFERENCE1"0P:\Clients\king county\B C\on-call bc\south plant wwtp\_CAD\02-SHEETS\C-CIVIL\224-1123626C2240101.dwg | Layout: C2240101 DEMO AND TESC PLAN AREA 16PLOTTED: Dec 22, 2017-06:45:49pm By dsaarenasXREFS: KCWTD-2015R0-Dsize-TB-Border.dwg; 224-1123626ExistSurv.dwg; 224-1123626CivilExistingBasemap.dwg; _WASHINGTON-SEAL_ED.dwg; WWTP Key Plan.dwg; 224-1123626CivilLimits.dwg; 224-1123626CivilTESC.dwg; 224-1123626CivilSheetNotes.dwgIMAGES:SOUTH TREATMENT PLANTBIOGAS AND HEAT SYSTEMS IMPROVEMENTSJAN 201815-xxxxxxxNO REVISION DESCRIPTION BY APVD DATEEFGHBCDAS. HildrethPRELIMINARY ISSUE DRAWING60% REVIEWJANUARY 2018C2240101D. SaarenasB. IddinsE. Davido1" = 20'.0E. DavidoMATCH LINE - SEE DWG C224010233723MATCH LINE - SEE DWG C2240105.KEY NOTES:INSTALL 132 LFPERIMETER PROTECTION(36 THIS SHEET) PERGENERAL NOTE 1INSTALL 44 LF PERIMETERPROTECTION PERGENERAL NOTE 1INSTALL 95 LF PERIMETERPROTECTION PERGENERAL NOTE 1DELINEATE DISTURBANCELIMITS WITHHIGH-VISIBILITY FENCE INPERVIOUS AREASINSTALL CATCH BASINFILTER123451253543C22401515C22401511C22401513C22401513C22401515C22401515C2240151
King County South Plant Biogas and Heating System Improvements 1 ESA / D150513.00
CUP / Site Plan Review Submittal February 2018
Construction Mitigation Description
Proposed construction dates (begin and end dates)
Project construction is scheduled to occur from May 2019 to May 2021.
Hours and days of operation
Construction is expected to be limited to normal working hours (7:00 am to 5:00 pm) and weekdays (no
weekend work or work on legal holidays).
Proposed hauling/transportation routes
Project construction will require approximately 750 truck trips over approximately two years in order to
deliver materials including concrete, asphalt, and other building materials. Haul routes will be determined
by the contractor. The construction contractor will be required to develop a detailed traffic control plan
for review and approval by the City of Renton prior to commencing any work or traffic control within the
City’s right-of-way, though not anticipated. These plans would be required to conform with all City of
Renton requirements and would document the construction contractor’s proposed haul routes.
Measures to be implemented to minimize dust, traffic and
transportation impacts, erosion, mud, noise, and other
noxious characteristics
The construction contractor will be required to develop a detailed traffic control plan as well as an
environmental mitigation plan prior to commencing the work on site. These plans will be required to
conform with all City of Renton requirements and will document the construction contractor’s procedures
for minimizing dust, traffic, erosion, noise, and other impacts resulting from construction traffic. Best
Management Practices (BMPs) identified in the SEPA Checklist for the project are detailed below. Other
BMPs may be identified by the contractor.
BMPs to Minimize Dust
Street sweeping, watering exposed soil surfaces, and covering soil stockpiles to help minimize the amount
of fugitive dust and particulate pollution to the surrounding areas.
BMPs to Minimize Traffic and Transportation impacts
Truck trips will be substantially minimized by relocating spoils excavated as part of the project to another
location on the South Treatment Plant (STP) site. Spoils excavated for construction of the Heat and
Energy Recovery Building (HERB) will be placed on an approximately 1-acre area south of the digesters
located within an open lawn area in the center of the STP site (and compacted and seeded to match
existing grades and slopes). BMPs related to truck trips required for materials and equipment will be
identified in the traffic control plan.
Revised Geotechnical Report
King County South Treatment Plant
Biogas and Heat Systems Improvements
Renton, Washington
January 6, 2017
Submitted To:
Mr. Ian McKelvey
Brown and Caldwell
701 Pike Street, Suite 1200
Seattle, Washington 98101
By:
Shannon & Wilson, Inc.
400 N 34th Street, Suite 100
Seattle, W ashington 98103
21-1-22210-001
400 NORTH 34TH STREET, SUITE 100
P.O. BOX 300303
SEATTLE, WASHINGTON 98103
206-632-8020 FAX 206-695-6777
TDD 1-800-833-6388
www.shannonwilson.com 21-1-22210-002
December 8, 2017
Mr. Ian McKelvey
Brown and Caldwell
701 Pike Street, Suite 1200
Seattle, WA 98101
RE: GEOTECHNICAL REPORT ADDENDUM, BIOGAS AND HEAT SYSTEMS
IMPROVEMENTS PROJECTS, KING COUNTY SOUTH TREATMENT PLANT,
RENTON, WASHINGTON
Dear Mr. McKelvey:
We are pleased to submit this letter to serve as an addendum to our Revised Geotechnical Report
for the South Treatment Plant Biogas and Heat Systems Improvements project dated
January 6, 2017. This addendum summarizes our recent geotechnical evaluation of three
geotechnical issues that were not addressed in our previous report:
1. Infiltration rates to aid in the design of stormwater infiltration facilities
2. Pavement sections for a small area of driveway/parking
3. Evaluation of coal mine hazards
Our services were performed in accordance with Amendment No. Three to the Subcontract
between Brown and Caldwell and Shannon & Wilson, Inc. for Geotechnical Services, dated
June 5, 2017.
STORMWATER INFILTRATION RATES
Shannon & Wilson staff visited the proposed project site from October 9 to 12, 2017, to perform
pilot infiltration tests (PITs) to evaluate suitability of soils for infiltration facilities. Clearcreek
Contractors (Clearcreek), under subcontract to Shannon & Wilson, Inc., excavated three test pits
designated TP-1, TP-2, and TP-3 at locations determined by the project civil engineer, Davido
Consulting Group. The approximate locations of the test pits are shown on the attached
TECHNICAL INFORMATION REPORT
(FULL DRAINAGE REVIEW)
KING COUNTY SOUTH TREATMENT PLANT –BIOGAS AND HEAT SYSTEMS IMPROVEMENTS
PARCEL #:2423049006 &2423049097
ADDRESS:1200 MONSTER RD SW,RENTON,WA 98057
PROJECT #TBD
February 2018
For Submittal to
City of Renton
D AVIDO CONSULTING GROUP,INC.
15029 Bothell Way NE, Ste 600
Lake Forest Park, WA 98155
Phone: 206.523.0024
Fax: 206.523.1012
Owner:
King County Dept. of Natural
Resources & Parks
Wastewater Treatment Div.
Attn: Susan Hildreth
201 South Jackson Street
Seattle, Washington 98104
Phone: (206) 477-5537
701 Pike Street, Suite 1200
Seattle, Washington 98101
T: 206.624.0100
F: 206.749.2200
rs_trip_generation_memo_171130_v1
November 30, 2017
Susan Hildreth
King County Department of Natural Resources and Parks
Wastewater Treatment Division
King Street Center, Room 503
201 South Jackson Street
Seattle, Washington 98104 148642.630.2
Subject: South Plant Biogas and Heat Systems Improvements Project
Trip Generation Memo
Dear Ms. Hildreth:
In accordance with the City of Renton’s conditional use permit and site plan review ap-
plication requirements for the subject project, Brown and Caldwell developed the follow-
ing evaluation of expected traffic generation. As the new facilities are a replacement
and upgrade of existing biogas utilization and plant heating systems, and not new pro-
cesses, this project is not expected to have any impact on the number of traffic trips dur-
ing operation of the facility. As such, this evaluation is focused solely on construction
traffic trips.
At present, the expected construction dates for the project are from May 2019 to May
2021. Construction is expected to be limited to normal working hours (7:00 am to 5:00
pm) and weekdays (no weekend work or work on legal holidays). Work associated with
the project is confined within the plant boundaries and as a result, there are no signifi-
cant traffic impacts to public right-of-way as part of this project. The construction con-
tractor will be required to develop a detailed traffic control plan as well as an environ-
mental mitigation plan for review and approval by King County prior to commencing the
work on site. These plans will be required to conform with all City of Renton require-
ments and will document the construction contractor’s procedures for minimizing dust,
traffic, erosion, noise, and other impacts resulting from construction traffic.
The total number of construction trips will depend on the final staffing and means and
methods selected by the construction contractor. Generally, the project is expected to
require on average roughly 20 workers travelling to the site each weekday in personal
vehicles. Truck traffic will almost exclusively be for the delivery of materials and equip-
ment to the site and is expected to be on the order of 750 trips over the course of the
two-year construction period. The project currently does not include any removal of ex-
cavation materials from the site and as a result, truck traffic for hauling spoils off-site is
not expected.
Final
SOUTH TREATMENT PLANT BIOGAS AND HEAT
SYSTEMS IMPROVEMENT PROJECT
Wetland Assessment Report
Prepared for January 2018
King County Wastewater Treatment
Division
January 5, 2018
Chris Dew, King County WTD
Jessica Conquest, Environmental Science Associates
Karmen Martin, Environmental Science Associates
South Plant Biogas and Heating Systems (Temporary Construction Entrance) - Standard Stream Study
(for Shoreline Exemption Submittal)
As part of King County’s South Plant Biogas and Heating System Project, King County proposes to construct a
temporary construction entrance which will provide construction machinery access to the proposed onsite spoils
placement area. Work will be restricted to temporary grading for installation of the temporary construction
entrance. Construction and use of the temporary construction entrance would occur within a portion of the
shoreline jurisdiction of Springbrook Creek. This memorandum was prepared by Environmental Science
Associates to address information specified in RMC Section 4-8-120D.19 for a “Standard Stream Study”, and as
identified in the City of Renton Shoreline Exemption Submittal Requirements Bulletin.
Springbrook Creek was extensively modified and straightened for agricultural drainage in the 1920s by King
County Drainage District No. 1. The channel area abutting the project was improved in the 1980s and 1990s for
flood control by the City of Renton in cooperation with the Natural Resource Conservation Service. The stream is
constrained and channelized throughout the shoreline (City of Renton, 2010). Levees that define the streambank
limit the width of the riparian corridor (Parametrix, 2010).
Springbrook Creek is classified as Shoreline High Intensity under the City’s Shoreline Management Program.
Existing vegetation along the shoreline is typical native riparian forest species and includes a mixture of red alder,
willow species, Himalayan blackberry and sedges (Carex spp.) along with some ornamental trees. Conifers are
almost exclusively absent, and in those areas where shade is absent, reed canary grass is abundant. The
Springbrook Creek vegetated riparian area is separated from the project site by the plant driveway (Road “N”).
Chinook, Chum, Coho, Steelhead Trout, and Cutthroat Trout are found in Springbrook Creek, utilizing the habitat
primarily for migration (City of Renton, 2010). According to Washington Department of Fish and Wildlife
(WDFW) SalmonScape fish distribution data, fall Chinook, fall chum, and winter steelhead are present and coho
rear in the creek (WDFW, 2017). Under Washington State Water Quality Standards, Springbrook Creek is
categorized as “Spawning Rearing and Migration Habitat” for aquatic life use and “Primary Contact” for
recreational use. The Creek is on Washington Department of Ecology’s 303(d) list for violation of dissolved
oxygen and fecal coliform bacteria standards (Category 5) (King County, 2017).
AREA SHOWN ON THIS PLANWWTP KEY PLANNO SCALE12345DESIGNED/DRAWN:PROJECT ENGINEER:PROJECT ACCEPTANCE:DESIGN APPROVAL:CONTRACT NO:DRAWING NO:PROJECT FILE NO:SCALE:FACILITY NUMBER:DEPARTMENT OF NATURAL RESOURCES & PARKSWASTEWATER TREATMENT DIVISIONDATE:SHT NO / TOTALREVNO:BORDER FILE EDITION: KCWTD-2015R0-Dsize-TB-Border12345EFGHBCDACHECKED:REFERENCE1"0P:\Clients\king county\B C\on-call bc\south plant wwtp\_CAD\02-SHEETS\C-CIVIL\224-1123626C2240103.dwg | Layout: C2240103 DEMO AND TESC PLAN AREA 18PLOTTED: Dec 22, 2017-06:46:44pm By dsaarenasXREFS: KCWTD-2015R0-Dsize-TB-Border.dwg; 224-1123626ExistSurv.dwg; 224-1123626CivilExistingBasemap.dwg; _WASHINGTON-SEAL_ED.dwg; WWTP Key Plan.dwg; 224-1123626CivilLimits.dwg; 224-1123626CivilTESC.dwg; 224-1123626CivilSheetNotes.dwgIMAGES:SOUTH TREATMENT PLANTBIOGAS AND HEAT SYSTEMS IMPROVEMENTSJAN 201815-xxxxxxxNO REVISION DESCRIPTION BY APVD DATEEFGHBCDAS. HildrethPRELIMINARY ISSUE DRAWING60% REVIEWJANUARY 2018C2240103D. SaarenasB. IddinsE. Davido1" = 20'.0E. Davido33723MATCH LINE - SEE DWG C2240102.KEY NOTES:CONSTRUCTION EQUIPMENT ENTRY/EXIT(FROM SW 7TH ST)INSTALL CATCH BASIN FILTERCONTRACTOR TO SWEEP STREETS DAILY ORMORE FREQUENTLY AS REQUIRED TO REMOVETRACKED SEDIMENTEX CURB TO BE REMOVED FORCONSTRUCTION ACCESSINSTALL 335 LF (221 LF THIS SHEET)PERIMETER PROTECTION PER GENERALNOTE 1CONSTRUCTION STAGING & STOCKPILINGAREADELINEATE DISTURBANCE LIMITS WITHHIGH-VISIBILITY FENCE IN PERVIOUS AREASINSTALL 175'L x 25'W STABILIZEDCONSTRUCTION ENTRANCELAY BACK SLOPE FOR CONSTRUCTIONENTRANCE TO BE 3H:1V MAX12345678912432567831C22401514C22401513C22401515C2240151APPROX 200-FT SHORELINEJURISDICTION PER COR GISMAPPINGAPPROXIMATE OHWM(NOT SURVEYED)9Site Plan — Temporary Construction Entrance128'PLANT DRIVEWAYSPRINGBROOK CREEKAPPROXIMATE OHWM(NOT SURVEYED)APPROXIMATE 200-FT SHORELINEJURISDICTION PER COR GIS MAPPINGTEMPORARYCONSTRUCTIONENTRANCE
DEPARTMENT OF COMMUNITY
AND ECONOMIC DEVELOPMENT
Page 1 of 2 LUA18-000188
ADVISORY NOTES TO APPLICANT
The following notes are supplemental information provided in conjunction with the administrative land use
action. Because these notes are provided as information only, they are not subject to the appeal process for
the land use action.
Planning:
(Contact: Clark H. Close, 425-430-7289, cclose@rentonwa.gov)
1. RMC section 4-4-030.C.2 limits haul hours between 8:30 am to 3:30 pm, Monday through Friday unless
otherwise approved by the Development Services Division.
2. Commercial and other nonresidential construction activities are restricted to the hours between seven
o’clock (7:00) a.m. and eight o’clock (8:00) p.m., Monday through Friday. Work on Saturdays shall be
restricted to the hours between nine o’clock (9:00) a.m. and eight o’clock (8:00) p.m. No work shall be
permitted on Sundays.
3. Within thirty (30) days of completion of grading work, the applicant shall hydroseed or plant an
appropriate ground cover over any portion of the site that is graded or cleared of vegetation and where
no further construction work will occur within ninety (90) days. Alternative measures such as mulch,
sodding, or plastic covering as specified in the current King County Surface Water Management Design
Manual as adopted by the City of Renton may be proposed between the dates of November 1st and
March 31st of each year. The Development Services Division’s approval of this work is required prior to
final inspection and approval of the permit.
4. A National Permit Discharge Elimination System (NPDES) permit is required when more than one acre is
being cleared.
5. The applicant may not fill, excavate, stack or store any equipment, dispose of any materials, supplies or
fluids, operate any equipment, install impervious surfaces, or compact the earth in any way within the
area defined by the drip line of any tree to be retained.
6. The applicant shall erect and maintain six foot (6') high chain link temporary construction fencing around
the drip lines of all retained trees, or along the perimeter of a stand of retained trees. Placards shall be
placed on fencing every fifty feet (50') indicating the words, “NO TRESPASSING – Protected Trees” or on
each side of the fencing if less than fifty feet (50'). Site access to individually protected trees or groups
of trees shall be fenced and signed. Individual trees shall be fenced on four (4) sides. In addition, the
applicant shall provide supervision whenever equipment or trucks are moving near trees.
7. This permit is shall comply with the Bald and Golden Eagle Protection Act. The permitted is responsible
for adhering to the U.S. Fish and Wildlife Service National Bald Eagle Management Guidelines (2007) and
/or your U.S. Fish and Wildlife Service permit.
Development Engineering:
(Contact: Justin Johnson, 425-430-7291, JTJohnson@rentonwa.gov)
1. See Attached Development Engineering Memo dated April 16, 2018.
Fire Authority:
(Contact: Corey Thomas, 425-430-7024, cthomas@rentonwa.gov)
1. Fire impact fees are applicable at the rate of $ 0.15 per square foot for retail. This fee is paid at time of
building permit issuance.
ADVISORY NOTES TO APPLICANT
Page 2 of 2 LUA18-000188
2. The preliminary fire flow is 2,000 gpm. A minimum of two fire hydrants are required. One within 150-
feet and one within 300-feet of the building. One hydrant must be within 50 feet of the fire
department connection.
3. Approved fire sprinkler and fire alarm systems are required throughout the building. Direct outside
access is required to the fire sprinkler riser room. Fire alarm system is required to be fully addressable
and full detection is required. Separate plans and permits required by the fire department.
4. Fire department apparatus access roadways are required. Roadways shall be modified to meet or
exceed the fire code minimum in and around the proposed new building. Fire lanes are required to
meet 20-feet width with 25-foot inside and 45-feet outside turning radius. Roadways shall support a
minimum of a 30-ton vehicle and 75-psi point loading. Fire Lane signage required for onsite roadways.
Technical Services:
(Contact: Amanda Askren, 425-430-7369, aaskren@rentonwa.gov)
1. Reviewed.
Community Services:
(Contact: Leslie Betlach, 425-430-6619, lbetlach@rentonwa.gov)
1. Regarding the request for the Street Modification, there is currently a discontinuous sidewalk/trail
system (missing link) along Oakesdale Ave SW (south side) east of Monster Rd SW, to approximately
300 feet west of SW 7th St. Completing this missing sidewalk link with street landscaping is
recommended for safe pedestrian access along a heavily traveled street.
2. Coordination with King County regarding the Lake to Sound Trail construction and roadway access,
detours, etc. is recommended.
Police:
(Contact: Cyndie Parks, 425-430-7521, cparks@rentonwa.gov)
1. Reviewed.
Building:
(Contact: Craig Burnell, 425-430-7290, cburnell@rentonwa.gov)
1. Recommendations of the geotechnical report must be followed as a condition of building permits.
DEPARTMENT OF COMMUNITY
AND ECONOMIC DEVELOPMENT
M E M O R A N D U M
DATE:April 16, 2018
TO:Clark Close, Senior Planner
FROM:Justin Johnson, Civil Plan Reviewer
SUBJECT:Utility and Transportation Comments for King County
LUA18-000188
NOTE: The applicant is cautioned that information contained in this summary is preliminary and non-
binding and may be subject to modification and/or concurrence by official City decision-makers. Review
comments may also need to be revised based on site planning and other design changes required by
City staff or made by the applicant.
I have completed a preliminary review of the application for the King County Biogas and Heat Systems
Improvements.
WATER COMMENTS
1. Water service for the existing building shall be serviced by the existing private 12” CW line that
loops around the property. Applicant is to ensure that the water line that they connect to is the
correct line.
2. The applicant will not need to pay additional SDC Fees as long as their connection point is on
their private system.
3. Plans for the Building permit will need to clearly show the connections to the private lines for
domestic water as well as the sprinkler system (if required). These plans will also need to
indicate the locations of the City of Renton 12” water meter.
SEWER COMMENTS
1. Sewer service is provided by City of Renton.
2. There is an existing 12-inch wastewater main located in Oakesdale Ave SW (see City plan no. S-
199807).
3. Since the sewer line will be connected to the system within the treatment plant there will be no
SDC fees for sewer are required to be paid.
King County Biogas and Heat Systems Improvements – LUA18-000188
Page 2 of 2
April 16, 2018
STORM DRAINAGE COMMENTS
1. There is an existing storm water system within the property.
2. A drainage report complying with the 2017 City of Renton Surface Water Manual and City
Amendments was prepared by Davido Consulting Group, Inc. Based on the City’s flow control
map, the site falls within the Peak Rate Flow Control Standard area matching Existing Site
Conditions and is within the Black River Drainage Basin.
3. A geotechnical report was prepared by Shannon & Wilson, Inc. dated January 6 2017. There has
been two addendums submitted as well. Information on the water table and soil permeability,
with recommendations of appropriate flow control BMP options with typical designs for the site
from the geotechnical engineer, were submitted within the second addendum of the geotechnical
report. There were three PIT tests taken to measure the permeability of the soil and the
infiltration rates were measured at approximately 0.02 inch/hour (without correction factors).
4. Applicant is proposing to do a Treatment Trade as described in section 1.2.8.2C that meets the
City of Renton requirements as outlined in the Surface Water design manual. For City approval,
the applicant must show the 2,935 SF area of the offsite roadway that will flow onsite and be
collected and treated to compensate for the 2,844 SF of onsite area not collected and treated.
5. Surface water system development fee is $0.641 per square foot with a minimum fee of $1,608.00
for the new impervious surface. This is payable prior to issuance of the construction permit.
6. Construction Storm water General Permit from the Department of Ecology is required if clearing
and grading of the site exceeds one acre.
7. A Civil Construction Plan and Permit is required for the storm system improvements proposed by
the project.
TRANSPORTATION/STREET COMMENTS
1. Applicant has submitted a street modification that was approved through the latest project within
the King County Waste Water treatment facility. This waiver was approved.
GENERAL COMMENTS
1. The fees listed are for 2017. The fees that are current at the time of the respective permit issuance
will be levied. Please see the City of Renton website for the current development fee schedule.
2. Retaining walls that are 4’ or taller from bottom of footing and stormwater detention vaults will
require a separate building permit. Structural calculations and plans prepared by a licensed
engineer will be required as part of the building permit review.
3. All civil plans shall conform to the current City of Renton survey and drafting standards. Current
drafting standards can be found on the City of Renton website.
4. A separate plan submittal will be required for a construction permit for utility work and street
improvements. All plans shall be prepared by a licensed Civil Engineer in the State of Washington.
5. Please see the City of Renton Development Engineering website for the Construction Permit
Application and Construction Permit Process and Submittal Requirements. Please contact the City
to schedule a construction permit intake meeting.
6. All plan review for the City is now paperless. Please see http://rentonwa.gov/paperless/ for more
information.