HomeMy WebLinkAboutEx09_Geotechnical_ReportMEMORANDUM
Project No. 190398 - Task 3
January 14, 2020
To: Russ Gaston, PE and Charles Dewey, PE, Otak
From:
Elson T. “Chip” Barnett, LEG
Senior Engineering Geologist
ebarnett@aspectconsulting.com
Erik O. Andersen, PE
Principal Geotechnical Engineer
eandersen@aspectconsulting.com
Re: City of Renton, Preliminary Stormwater Feasibility Evaluation
Monroe Avenue NE Storm System Improvements
This memorandum, prepared by Aspect Consulting, LLC (Aspect), provides Otak and the City of
Renton (City) with an overview of local geology, available geotechnical data, description of data
reviewed for the infiltration feasibility GIS-based analysis, the resulting shallow infiltration
feasibility map, and recommended next steps on the Monroe Avenue NE Storm System
Improvement Project (Project).
In support of the Project, Aspect completed a desktop-level GIS-based geological survey for an
approximately 245-acre stormwater subbasin (Subbasin) in Renton, Washington. We created maps
of surface conditions, including ground surface topography, aerial photography, surficial geology,
slopes, wetlands, critical areas, and existing facilities. Existing geotechnical reports and studies
within the area of study were included in the review to include measured data where available. We
evaluated the combination of this GIS data and existing reported soils data in combination to
develop a shallow infiltration feasibility map that identifies areas expected to have high, medium,
and low capacity for shallow infiltration. This memorandum is intended for use by the Otak team as
input to further investigate particular areas or sites within the Subbasin as preferential stormwater
infiltration areas.
The following sections provide background on the Project, an overview of local geology, available
geotechnical data, a description of data reviewed for the infiltration feasibility GIS-based analysis,
the resulting shallow infiltration feasibility map, and recommended next steps for the Project.
earth +w ater Aspect Consulting, LLC 710 2nd Avenue Suite 550 Seattle, WA 98104 206.328.7443 www.aspectconsulting.com
1/14/2020
1/14/2020
EXHIBIT 9
RECEIVED
Clark Close 08/18/2023
PLANNING DIVISION
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
Otak MEMORANDUM
January 14, 2020 Project No. 190398 - Task 3
Page 2
Project Background
The Project encompasses the Subbasin in the Renton Highlands area (Figure 1). A 670-foot, 36-
inch perforated pipe along NE 2nd Street and a 200-ft, 48-inch perforated pipe along King County
Access Road drain portions of the stormwater runoff. In addition, numerous areas throughout the
Subbasin are drained by points of infiltration and stormwater ponds (Figure 2).
In 1994, a large rain event caused flooding in the street along Monroe Avenue NE, south of NE 4th
Street, and erosion of the northeast corner of the Upper Balch Pit, a privately-owned gravel pit
(301 Monroe Avenue NE). In order to accommodate any future high-flow runoff, the City provided
the property owner with a temporary easement. The easement allowed construction of one 18-inch
and one 24-inch overflow pipe, which would discharge flows into the pit during high flow events.
This temporary system has prevented roadway and property flooding since the original event.
However, a recent Application to the City to redevelop the Upper Balch Pit site will remove the two
overflow pipes from operation. In order to minimize risk of property damage or incidents nearby, a
new approach to managing high flow runoff needs to be constructed prior to the removal of the
pipes to allow the City to continue to manage stormwater within the Subbasin.
Overview of Local Geology
Local soils will directly inform the feasibility for infiltration across the Subbasin. Based on our
review of the geologic map (Mullineaux, 1965), the Subbasin is underlain by Pleistocene Vashon
Stade continental recessional stratified drift, glaciofluvial deposits (Qpa), and Vashon Stade
continental glacial till (Qgt). The glaciofluvial deposits consist chiefly of well-sorted sand and
gravel with few fines. The unit is subdivided according to origin and topographic form with
outwash along the Cedar River. The glacial till deposits consist of a diamict of dense to very dense
silty sand with gravel.
The Subbasin is divided into two geologic units, glacial till and outwash (drift), as shown on
Figure 3.
Data Review
Aspect compiled and reviewed data, including GIS data from the City of Renton, King County, and
various state agencies, as well as geotechnical reports made available by the City of Renton. The
following sections describe the various data reviewed.
Topography
King County Light Detection and Ranging (LiDAR) data with a 3-ft cell size resolution covers the
Subbasin. Ground surface elevations developed from the 2016 King County LiDAR data (2019)
and 5-foot topographic contours from the City of Renton are shown on Figure 4. The Subbasin
topography ranges from Elevation 425 1 feet in the northeast to Elevation 320 feet in the southwest
portion of the Project area.
1 1 Elevations referenced to North American Vertical Datum of 1988 (NAVD88).
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
Otak MEMORANDUM
January 14, 2020 Project No. 190398 - Task 3
Page 3
Critical Areas
The City of Renton has established a set of Critical Areas Regulations protect health, safety,
welfare, and property by minimizing adverse environmental impacts due to development within and
near to critical areas. (City of Renton, 2019a)
The mapped extent of critical areas within the City of Renton are available on the City’s Critical
Area Inventory maps and GIS data from the City’s data download portal (City of Renton, 2019b).
Mapped critical areas for the Subbasin are shown on Figure 5.
• Flood Hazard Areas – The Federal Emergency Management Agency (FEMA) 100-year
Floodplain dataset shows no mapped floodplain areas within the Subbasin.
• Wetlands and Streams – City of Renton Wetland and Stream Corridor Critical Areas
Inventory shows one small wetland area (approximately 7800 sq ft) within the Subbasin. No
significant streams or rivers flow through the Subbasin.
• Erosion Hazard Areas – City of Renton Erosion Hazard Areas show areas subject to
erosion hazards. There are no high erosion hazard areas and only localized moderate
erosion hazard areas within the Subbasin.
• Landslide Hazard Areas – The City of Renton Landslide Hazard maps approximately
16 acres of areas with moderate risk of landslides within the Subbasin. The largest of which
is 4 acres.
• Seismic Hazard Areas – The City of Renton Seismic Hazard Areas show no known
hazards in the Subbasin.
• Steep Slope Hazard Areas – The City of Renton Steep Slopes Areas, created from the 2016
King County LiDAR data, defined slopes greater than 25 percent as sensitive. There are
localized slopes greater than 25 percent and smaller areas greater than 40 percent that likely
represent areas of cut and fill slopes within the Subbasin.
• Wellfield Capture Zones – The City of Renton Wellfield Capture Zones do not lay within
the Subbasin.
• Group A and B drinking water – Well locations were downloaded from the Washington
State Department of Health (2019). There are no water sources located within the Subbasin.
• Environmental Data – The Washington State Department of Ecology’s Facility Index,
includes state Model Toxics Control Act (MTCA) cleanup and federal cleanup (Superfund)
sites. It includes facilities with known or suspected contamination to soil and groundwater
in any stage of cleanup. This data is shown on the map (star symbol) and may be useful in
site screening when considering potential infiltration feasibility.
Geotechnical, Soil, and Groundwater Data Review
Aspect reviewed available GIS data and reports to characterize the soil and the soil’s potential to
infiltrate stormwater runoff. Our methods and findings are described below.
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
Otak MEMORANDUM
January 14, 2020 Project No. 190398 - Task 3
Page 4
Geotechnical and Soil Data
Using the Washington Geological Survey 1:24,000 Surficial Geologic Units map and geotechnical
reports provided by the City, Aspect mapped 94 subsurface locations to assess feasibility for
stormwater infiltration. To assist in the infiltration assessment, information about the explorations,
including depth to groundwater, depth to glacial till, and infiltration rate testing, was incorporated
into a GIS database.
In general, the subsurface data corroborate the geologic mapping with outwash and till units
observed as mapped on Figure 3, with some exceptions. GeoEngineers (2006) observed outwash
deposits on the order of a few feet overlying glacial till at a depth of approximately 5 feet below
ground surface (bgs) in areas mapped as glacial till. Stratigraphically recessional outwash typically
overlies glacial till.
Just south of the Subbasin at the King County Regional Communications and Emergency
Coordination Center, HWA GeoSciences (HWA, 2002) reported a sequence of recessional outwash
overlying glacial till, over unsaturated advance outwash. HWA evaluated shallow infiltration
feasibility using pilot infiltration testing (PIT) methods and correlation to grain-size distribution.
Groundwater
There is no available GIS layer that maps depth to groundwater or areas of shallow groundwater
across the Subbasin. Areas of shallow groundwater are typically less than ideal for infiltration.
Figure 3 shows the available depth to groundwater information compiled by the 15 geotechnical
reports reviewed. In general, shallow groundwater perches on glacial till in the east areas of the
Subbasin. There is no groundwater data available within the western portion of the Subbasin that
includes deposits of outwash, however Aspect (2019) did observe groundwater immediately west of
the Subbasin within outwash at depths greater than 50 feet, as shown on Figure 3.
Shallow Infiltration Feasibility Assessment and Map
Three of the geotechnical studies we reviewed provided infiltration testing at exploration locations
completed in outwash (Aspect, 2019, GeoEngineers, 2006, and HWA, 2001) and glacial till (Otto
Rosenau and Associates, 2011). The infiltration rates for glacial till are considerably lower, at less
than 5 inches per hour compared to those measured in recessional outwash that are greater than the
maximum allowable design infiltration rate of 20 inches per hour. Available infiltration data are
provided below in Table 1.
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
Otak MEMORANDUM
January 14, 2020 Project No. 190398 - Task 3
Page 5
Table 1. Geotechnical Explorations and Infiltration Data
Exploration
Type Consultant Exploration
Name
Geologic
Unit
Infiltration Rate
(in/hr) Site Location
Monitoring
Well Aspect MW-1 Glacial
outwash
33.9
(20 design rate) 3005 NE 4th St
Monitoring
Well Aspect MW-2 Glacial
outwash
106.6
(20 design rate) 3005 NE 4th St
Test Pit HWA TP-6 Glacial
outwash
>150
(15 design rate) 3511 NE 2nd St
Hand Auger GeoEngineers HA-4 Glacial
outwash* 8.1* 475 Union Ave NE
Hand Auger GeoEngineers HA-5 Glacial
outwash* 7.7* 475 Union Ave NE
Hand Auger GeoEngineers HA-6 Glacial
outwash* 5.1* 475 Union Ave NE
Test Pit Otto Rosenau
& Assoc. TP-1 Glacial till 4.9 421 Union Ave NE
Test Pit Otto Rosenau
& Assoc. TP-3 Glacial till 1.3 421 Union Ave NE
Test Pit Otto Rosenau
& Assoc. TP-4 Glacial till 0.3 421 Union Ave NE
* GeoEngineers infiltration rates reflect testing in shallow glacial outwash overlying glacial till at a depth of
approximately 5 feet bgs.
We assimilated the mapped data and previous studies and assessed shallow infiltration feasibility
within the Subbasin. The unique combinations of the factors show areas that are more or less likely
to be feasible for infiltration. The combinations of the following input data within the Subbasin are
provided below:
• Soil Permeability
• Surface Slope Classification
• Geologic Hazard Areas
Soil Permeability
The permeability of a soil is the core factor in determining its feasibility for infiltration. Typically,
higher permeability soils are more feasible for shallow stormwater infiltration. If the soil cannot
infiltrate runoff effectively, flooding and water quality issues can occur. The properties of the
surface soils in the Subbains were evaluated for their permeability and categorized into two
permeability groups (Figure 8):
• Low permeability (infiltration observed at 0-5 inches/hour)
• High permeability (infiltration observed at greater than 5 inches/hour)
Surface Slope Classification
The steepness of a surface slope is a factor in the potential for runoff to effectively infiltrate. If the
ground surface is too steep, water can daylight down the slope from the point of infiltration. Steeper
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
Otak MEMORANDUM
January 14, 2020 Project No. 190398 - Task 3
Page 6
slopes can pose design challenges. The City of Renton Critical Area regulations define medium
landslide hazards as areas with slopes between 15 and 40 percent. Spatial analysis was used to
calculate the slope percentage over the Subbasin from the King County 2016 LiDAR data (King
County, 2019). Areas within the Subbasin fall within one of three categories:
• Good: Slopes less than 8 percent
• Moderate: Slopes between 8 and 15 percent
• Poor: Slopes greater than 15 percent
These categories reflect previous observations across the region of slopes in relation to infiltration
and potential hazard issues due to ground surface slope. The surface slope categories over the
Subbasin are shown on Figure 7.
Geologic Hazard Areas
Three input datasets from the City’s available Critical Area Inventory were used to identify
geologic hazard areas to avoid from potential infiltration site locations. Erosion, Landslide, and
Seismic Hazard areas were considered poor for shallow infiltration (Figure 6).
Soil Infiltration Map
Figure 9 shows areas across the Subbasin that are expected to have good, moderate, and poor
capacity for shallow infiltration (generally less than 10 feet deep).
• Good – Shallow infiltration is expected to be feasible, unlikely to pose hazards, and cost
effective.
• Moderate – Shallow infiltration is expected to be feasible with slopes are between 8 and 15
percent
• Poor – Shallow infiltration is expected to be low or risks could be high. Areas shown
mapped as Poor may not necessarily exhibit poor infiltration upon further site investigation.
Recommendations and Next Steps
Our recommendations for next steps on the Project as follows:
• Complete a site reconnaissance in coordination with City staff to observe subsurface
conditions at the Greenwood Memorial Park and some of the City stormwater facility
discharge points.
• Identify explorations that include borings and monitoring wells in the southwest portion of
the Subbasin where infiltration appears most feasible. We anticipate five borings along
Monroe Ave NE south of NE 4th Street, along NE 4th Street west of Queen Avenue NE, and
along 3rd Avenue NE would be well suited for explorations and may be needed if mounding
analysis is required. We recommend two of the five monitoring wells be installed along NE
4th Street, one along Monroe Avenue, and one to two along NE 2nd Street. The monitoring
wells should be installed with data loggers and to record seasonal high groundwater.
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
Otak MEMORANDUM
January 14, 2020 Project No. 190398 - Task 3
Page 7
• Identify potential pilot infiltration testing locations.
References
Aspect Consulting, LLC, (Aspect) 2019, Geotechnical Evaluation – 60 Percent Design, King
County Parks and Recreation Division – Renton Shop, 3005 4th Street NE, Renton,
Washington, for Mr. Christopher Walling, Project Manager, HDR Architecture, Inc., May
31, 2019.
City of Renton, 2019a, Critical Areas Regulations, Chapter 4-03-5, accessed December 20, 2019.
City of Renton, 2019b Critical Area Data Download accessed on May 25, 2019,
https://rentonwa.gov/city_hall/administrative_services/Information_technology/maps___g_i
_s_data/data_download.
GeoEngineers, Inc., 2006, Geotechnical Engineering Services, President Park Substation, Renton,
Washington, File No. 0186-673-00, for Puget Sound Energy, February 22, 2006.
HWA GeoSciences, Inc. 2001, Geotechnical Engineering Report, King County Regional
Communications and Emergency Coordination Center, for Hewitt Architects,
August 16, 2001.
King County KCGIS Center GIS, 2016 LiDAR data, accessed on December 6, 2019,
http://www5.kingcounty.gov/gisdataportal/Default.aspx.
Mullineaux, D. R., 1965, Geologic map of the Renton quadrangle, King County, Washington, U.S.
Geological Survey, Geologic Quadrangle Map GQ-405, 1 sheet, scale 1:24,000.
Otto Rosenau & Associates, Inc., 2011, Infiltration Feasibility Study, Proposed Firestone Complete
Auto Care Facility, 421 Union Avenue Northeast, Renton, Washington, for FES Group,
January 17, 2011.
Washington State Department of Health, Division of Environmental Health, Office of Drinking
Water, 2019, Individual System Viewer, Accessed December 8, 2019.
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
Otak MEMORANDUM
January 14, 2020 Project No. 190398 - Task 3
Page 8
Reports Reviewed for Infiltration Mapping
Associated Earth Sciences, Inc., 2005, Subsurface Exploration, Geologic Hazard, and Geotechnical
Engineering Report, Proposed Le Development, Renton, Washington, Mr. Alex Le c/o Wu
Architecture, December 14, 2005.
Earth Solutions NW, LLC, 2006, Geotechnical Engineering Study, Proposed Highlands Square
Townhome Development, 343 Union Avenue Southeast, Renton, Washington, for Davis
Real Estate Group, September 27, 2006.
GeoEngineers, Inc., 2010, Geologic and Geotechnical Design, Olympic Pipe Line Milepost 109,
Landslide Stabilization Project, Renton, Washington, File No. 0894-188-00, for Olympic
Pipe Line Company, March 26, 2010.
Geospectrum Consultants, Inc., 2004, Geotechnical Consultations, Storm Water Infiltration
Feasibility, Tax Lots 518210-001, -0012, -0014, 254, 316 & 318 Union Avenue NE, Renton
Washington, for Redhawk Construction, December 17, 2004.
Geotech Consultants, Inc., 2013, Geotechnical Engineering Study, Proposed Taco Time Restaurant
and Second Retail Building, 4114 Northeast 4th Street, Renton, Washington, for Taco Time
Northwest, November 11, 2013.
Hong West & Associates, Inc., 1997, Geotechnical Report, King County Transfer Stations Seismic
Evaluation, First Ave. NE, Algona, Houghton, Factoria, and Renton Facilities, King
County, Washington, for ABKJ, Inc., July 18, 1997.
The Riley Group, Inc., 2007, Geotechnical Engineering Report, Proposed Walgreens Drugstore,
4105 & 4111 NE 4th Street, Renton, WA 98059, for Mr. Robert Sherry, Phillips Edison &
Company, November 14, 2007.
The Riley Group, Inc., 2012, Geotechnical Engineering Report, QFC 871 Fuel Station, 4615
Northeast 4th Street, Renton, Washington 98059, for Kroger, Inc., August 22, 2012.
Pacific Geo Engineering, LLC, 2007, Geotechnical Engineering Study for Union Avenue Property,
Renton, King County, Washington, for American Classic Homes, LLC, February 15, 2007.
Shannon & Wilson, Inc., 2005, Geotechnical Report, Heather Downs Park Development, Renton,
Washington, for J.A. Brennan Associates, PLLC, October 10, 2005.
Terra Associates, Inc., 2018, Geotechnical Engineering Evaluation, Upper Balch Development,
3005 NE 4th Street, Renton, Washington, for Mr. Mark Seagle, Seagle Properties, LLC,
November 9, 2018.
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
Otak MEMORANDUM
January 14, 2020 Project No. 190398 - Task 3
Page 9
Limitations
Work for this project was performed for Otak (Client), and this report was prepared consistent with
recognized standards of professionals in the same locality and involving similar conditions, at the
time the work was performed. No other warranty, expressed or implied, is made by Aspect
Consulting, LLC (Aspect).
Recommendations presented herein are based on our interpretation of site conditions, geotechnical
engineering calculations, and judgment in accordance with our mutually agreed-upon scope of
work. Our recommendations are unique and specific to the project, site, and Client. Application of
this report for any purpose other than the project should be done only after consultation with
Aspect.
Variations may exist between the soil and groundwater conditions reported and those actually
underlying the site. The nature and extent of such soil variations may change over time and may not
be evident before construction begins. If any soil conditions are encountered at the site that are
different from those described in this report, Aspect should be notified immediately to review the
applicability of our recommendations.
It is the Client's responsibility to see that all parties to this project, including the designer,
contractor, subcontractors, and agents, are made aware of this report in its entirety. At the time of
this report, design plans and construction methods have not been finalized, and the
recommendations presented herein are based on preliminary project information. If project
developments result in changes from the preliminary project information, Aspect should be
contacted to determine if our recommendations contained in this report should be revised and/or
expanded upon.
The scope of work does not include services related to construction safety precautions. Site safety is
typically the responsibility of the contractor, and our recommendations are not intended to direct
the contractor’s site safety methods, techniques, sequences, or procedures. The scope of our work
also does not include the assessment of environmental characteristics, particularly those involving
potentially hazardous substances in soil or groundwater.
All reports prepared by Aspect for the Client apply only to the services described in the
Agreement(s) with the Client. Any use or reuse by any party other than the Client is at the sole risk
of that party, and without liability to Aspect. Aspect’s original files/reports shall govern in the event
of any dispute regarding the content of electronic documents furnished to others.
Please refer to Appendix A titled “Report Limitations and Guidelines for Use” for additional
information governing the use of this report.
We appreciate the opportunity to perform these services. If you have any questions please call Chip
Barnett, Senior Engineering Geologist, at 206-413-5398.
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
Otak MEMORANDUM
January 14, 2020 Project No. 190398 - Task 3
Page 10
Attachments: Figure 1 – Site Location Map
Figure 2 – Stormwater Map
Figure 3 – Surficial Geologic Units
Figure 4 – Surface Elevation
Figure 5 – Critical Areas
Figure 6 – Geologic Hazard Areas
Figure 7 – Surface Slope Classification
Figure 8 – Soil Permeability
Figure 9 – Shallow Infiltration Feasibility
Appendix A – Report Limitations and Guidelines for Use
V:\190398 City of Renton Monroe Ave NE Storm System Improvements\Deliverables\Preliminary Technical Memo\Final\Preliminary Stormwater Feasibility
Evaluation_20200114.docx
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
FIGURES
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
^GIS Path: T:\projects_8\CityofRenton\MonroeAveNEStormImprovements_190398\Delivered\PreliminarySWFeasibilityEvaluation\Fig 01 Site Location Map.mxd || Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Feet || Date Saved: 1/9/2020 || User: ecrumbaker || Print Date: 1/9/2020Site Location MapPreliminary Stormwater Feasibility EvaluationMonroe Avenue NE Storm System ImprovementsCity of Renton, Washington
FIGURE NO.1JAN-2020
PROJECT NO.190398
BY:EAC / ETB
REVISED BY:- - -
0 2,000 4,000
Feet
!
!
!
#!
!
!
!
!(
W A S H I N G T O N
SITELOCATION
Bellingham
Olympia
Port Angeles
Seattle Spokane
Tacoma Wenatchee
Yakima
!
!
!
!
#
!(
SITELOCATION
PugetSoundLake WashingtonElliottBay Bellevue
Kent
Renton
Seattle
C edar Riv
e
r
GreenRiverBasemap Layer Credits || Esri, HERE, Garmin, (c) OpenStreetMap contributors, and the GIS user communitySources: Esri, HERE, Garmin, Intermap, increment P Corp., GEBCO, USGS, FAO, NPS, NRCAN, GeoBase, IGN, Kadaster NL, Ordnance Survey, Esri Japan, METI, Esri China (Hong Kong), (c) OpenStreetMap contributors, and theGIS User Community
SITE LOCATION
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
,,,,,,,,,,,,,,,,,,,,
,,,,
,,,,,,
,,,,,,,,
,,
,,,,,,!D,,,,,,,,,,,,,,,,,,!D,,,,,,,,,,,,,,,,,,,,
,,
,,!D,,,,,,!D,,,,,,
,,!D,,!D,,,,
,
,
,,,,!D,,,,,,,,!D,,,,,,,,,,,,!D,,,,,,,,,,,,,,,,!D,,,,!D,,
,
,,,,,,,,,,,,,,,,,,,,,,,!D,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,!D,,,,!D,,
,,,,,,
,,!D,,!D,,,,,,!D,,,,,,,,!D,,,,,,,,,,,,
,,
,,
,,,,,,,,!D,,,,,,,,!D,,,,,,,,!D,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,!D,,,,,,!D,,!D,,,,!D,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,
,,,,,,,,,,,,
,,
,,,,!D,,
,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,!D,,,,,,,,!D,,,,,,!D,,!D,,,,,,,,,,,,,,,,,,,,!D,,,,,,!D,,!D,,,,!D,,,,,,,,,,!D,,,,,,,,
,
,,,!D
,,!D,,!D,,!D,,!D,,!D,,,,,,,,!D,,,,,,
,,,,!D,,!D,,,,
,,,,,,,,!D,,,,,,!D,,,,!D,,,,,,
,
,!D,,!D,,,,,,!D,,,,,,,,
,,,,,,,,,,,,,,,,!D,,!D,,!D,,,,!D,,!D,,,,!D,,,,!D,,,,,,!D,,!D,,!D
,,,,!D,,,,,,,,,,!D,,,,!D,,!D,,!D,,!D,,!D,,!D,,!D,,
,,
,,,,!D,,,,!D,,!D,,!D,,,,,,,,!D
,,,,,,!D,,,,,,!D,,,,!D,,!D,,,,,,,,!D,,!D,,
,,,,
,,
,,,,!D
,,,,,,,,!D,,
,,
,,,,,,,,,,,,")
")
")
")
")
")
")
")
")
")
")
")
")
")")
")
")
")
")
")
")
")
!(
")
")
")
")
")
")
")
")
!(
!(
!(
")
!(
")
")
!(
")
!(
")
")
")
")
")
")
")
")
")
")
")
")
!(
!(
")
!(
")
")
")
")
")
")
")
!(
")
")
")
")
")
!(
!(
")
")")
")
")
!(
!(
")
")")
")")
")")
!(
!(
")
!(
")
!(
!(
")
")
!(
!(
!(
!(
")
")")
!(
")
!(
!(
")
!(
!(
")!(
")
")
")
!(
")
")
!(
")
")
")
")
!(
")
")
")
!(
!(
")
!(
")
!(
!(
")
")
")
")
")
")
!(
"/!(
")
")
")
")
!(
")
")
")
")")
!(
!(
!(
!(
!(
!(
!(
!(
!(")
")
")
!(
!(
")
")
!(
")
")
")
")
")
®f
")
!(
")
")
!(
!(
!(
!(
!(
!(
")
")
")
!(
")
")
")
")
"/
")
!(
")
")
!(
")
")
")
")")
"/
®f
!(
®f
!(
!(
")
")
")
")
")
!(
!(
")
")
")
!(
")
®f
")
!(
")
")
")
!(
")
")
")")
")
!(
!(
")
")
")
")
")
")
")
")
")
")
!(
!(
!(
!(
!(
")
")
!(
!(
!(
!(
")
")
!(
")
")
®f
!(
")
!(
!(
")
")
!(
")
!(
!(
!(
!(
!(
")
!(")
!(
")
")
")
")
")
")
")
!(
!(
")
")
")
")
")
")")
")
")")")!(
")
")
")!(
!(
")
")
")
")
")
")
")
!(
")
!(
")
!(
")
!(
!(
")
!(
")
")
")
")
")
")")
!(
")!(
!(
")!(
!(
")
")
")
")
")
!(!(
")
!(
")
")
!(
")
!(
")
")
!(
!(
!(
")
")
")
")
!(
")
")
")
")
!(
")
!(
")
")
")
!(
")
!(
")
")")!(
")
")")
!(
!(
")
")
!(
!(!(
")
")
")
!(
")
")
")
!(
!(
")
")
")
")")
!(
")
!(
")
")
")
")
!(")
")")
")")")")")")
!(
!(
")")
")")")")!(
")")
")
")")")
")
")
")")")
")!(!(
")!(!(
!(")
!(
")
")!(!(!(!(")
!(!(!(
!(!(!(
")")
!(!(
!(
!(!(
!(
!(
!(!(!(
")
")
")
")
")
")
")
")
")
")
")
")
")
")
")
")")
!(
!(
!(
")
!(
!(
"/
!(
")
")
")
")
!(
")
")
")
")
")
")
")
")
")")
")
!(
!(
")
!(
!(
!(
")
")
")
")
")
")!(!(
")
!(
")
")!(
")
!(
")
")
!(
!(
")
")
")
")
!(
")
!(
")
")
!(
")
")
")
")
")
")
")
!(
")
!(
")
!(
")
!(
")
")
")
")
")
")
")
")
!(
")
")
")
")
!(
")
!(
!(
")
")
!(
")
")
!(")
")
")
")
")")
")
!(
")
")
")
")
!(
!(
")
")
")
")
")
")
!(
")
")
")
!(
!(
")
!(
")
")
")
!(
!(
")
")
")
")
")
!(
")
")
")
")
!(
")
!(
!(
!(
")
!(
")
")
")
")
")
!(
!(
!(
!(
")
")
")
")
")
!(
")
")
")
")
")
")
")
")
")
")
")
")
")
")
!(
")
")
!(
")
")
")
!(
")
!(
!(
")
")
!(
")
")
!(
!(
"/!(
")
")
!(
")
!(
")
!(
")
!(
")!(
!(
")
!(
!(
")
!(")!(
")
")
")
!(
")
!(
")
!(
!(
!(
!(
")
!(
")
!(
!(
")
!(
")
")!(
!(
")
")
")
")
!(
!(
")
!(
!(
!(
!(
")
")")
")
")
")
")
")
")
")
")
")
")
")
")")
")
!(
")
")
!(
")
!(
")
!(
!(
")
")
")!(
")
!(
")
!(
")
")
!(
!(
!(
")
")
!(
")
")
")
")
")
")
")
")
")
")
")
")
!(")
!(
!(
")
")
")
!(
")")
")
!(
!(
")
")
")
!(
!(
!(
")
!(
!(
")
")
")
")
")
")
!(
")
!(
!(
")
!(
!(
")
")
")
")
!(
")")
!(
")
")
!(
")
!(
!(")
")
!(")
!(
")
")
!(
")
")
")
")
")
")
!(
!(
!(
")
!(
")
")
!(")
")
!(
")
!(
!(
!(
")
!(
")
")
")
")
!(
!(
!(
")
")
")
")
")
!(
")
!(
")
!(
!(
")
")
!(
")
!(
!(
")")
")
")
!(
")
")
!(
")!(
")
")
")
")
!(
")
")
!(
")
")
!(
!(
")
")
")
")
")
!(
")
")
")
!(
")
")")
!(
")
")
")
")
!(
")
")
")
!(
")
")
")
")
")
")
!(
")")
")
")
")
")!(
")
")
")
")
")
")
")
")
")
")
")
")
")")
")")
")
")
")
")
")
")
!(
")
")
")
")
")
")
")
!(
!(
")")
!(")!(!(
!(
")")")
")
!(
")
")
!(
")
")
!(
!(")
")
")
")
")
!(
")
")
!(
")
")
")
!(
!(
")
")
")
")")
")
!(
")!(
")
")
")
!(
")
")
")
!(
")
")
")
!(
")
")
")
")
!(
!(
!(
")
")
")")
!(
")
")
")
")
!(
")
!(
")
!(
!(
")
")
")")
")
")
")
")
")
")
!(
")
")
!(")
!(
!(")
")
")
")
")
")
")
")
")!(
!(
")
")
")
")
")
!(!(
")
!(
")
")
")!(
!(
")
")
")
!(
")
")
")
")
")
")
!(
")
")
")
")
!(
")
")
")!(
")
")
")
")
!(
!(
")
!(
")")
!(
!(
")
")
")
")
!(
")")
!(
")
")
!(
")
")
")
")
")
!(
!(
!(
")!(
")
")")!(
!(
!(
!(
!(!(
!(
!(
")
")!(!(
")
")
")
")
")!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(!(
!(
!(!(!(!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(!(!(
!(
!(
!(
!(!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(!(
!(!(
!(!(!(!(!(!(!(!(
!(
!(!(!(
!(
!(!(!(!(
!(
!(!(
!(
!(!(
!(
!(
!(!(
!(
!(
!(
!(
!(!(!(!(!(
!(!(
!(
!(!(!(
!(
!(
!(
!(!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(!(!(!(!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(!(
!(
!(
!(
!(
!(!(
!(
!(!(
!(
!(!(
!(
!(
!(!(!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(!(!(!(!(!(!(!(!(
!(!(!(!(!(!(!(!(!(!(!(!(!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(!(
!(
!(
!(!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(!(
!(!(
!(
!(
!(!(!(!(
!(
!(!(
!(
!(
!(!(!(!(!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(!(!(
!(
!(
!(
!(
!(!(
!(
!(!(!(!(
!(!(!(
!(
!(!(
!(!(
!(
!(
!(
!(
!(!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(!(!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(!(
!(
!(
!(!(
!(!(
!(
!(!(
!(!(
!(
!(
!(
!(!(!(
!(!(!(
!(!(!(!(!(!(
!(
!(!(!(!(!(
!(!(!(
!(
!(
!(!(
!(!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(
!(!(
!(
!(
!(
!(
!(
!U
")
")
")
")
")
")
")
")
!!(
!!(
!!(
!!(
!!(
!!(
!!(!!(
!!(
!!(
!!(
!!(!!(!!(
!!(!!(
!!(!!(
!!(
!!(
!!(!!(!!(
!!(
!!(
!!(
!!(!!(
!!(
!!(
!!(
!!(
!!(
!!(
!!(
!!(
!!(!!(
!!(!!(
!!(
!!(
!!(
!!(!!(
!!(
!!(
!!(
!!(
!!(
!!(
!!(
!!(
!!(
!!(
!!(
!!(
!!(
!!(!!(!!(
!!(
!!(
!!(
!!(
!!(
!!(
!!(!!(
!!(!!(
!\
!\
!\
!\
!\
!\
!\
!\!\
!\
!\!\
!\
!\
!\
!\!\!\
!\
!\!\
!\
!\
!\!\
!\
!\!\
!\
!\
!\!\
!\!\
!\!\!\!\
!\!\!\
!\!\
!\!\!\
!\
!\!\
!\
!\
!\
!\
!\!\
!\
!\
!\
!\
!\
!\
!\
!\
!\
NE 4TH ST
QUEEN AVE NEMONROE AVE NENE 2ND ST
NE 6TH ST
NE 8TH ST
Upper Balch Pit UNION AVE NEGIS Path: T:\projects_8\CityofRenton\MonroeAveNEStormImprovements_190398\Delivered\PreliminarySWFeasibilityEvaluation\Fig 02 Stormwater Map.mxd || Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Feet || Date Saved: 1/9/2020 || User: ecrumbaker || Print Date: 1/9/2020FIGURE NO.2JAN-2020
PROJECT NO.190398
BY:EAC / ETB
REVISED BY:- - -
Stormwater MapPreliminary Stormwater Feasibility EvaluationMonroe Avenue NE Storm System ImprovementsCity of Renton, Washington
0 440220
Feet
")Inlet
!(Manhole
"/Utility Vault
®f Unknown Structure
!U Lift Station
!\Existing Flow Control BMP
!!(Outlet
Culvert
,,Pipe
Ditch
Stormwater Ponds
Project Boundary
Project Boundary(1000-ft Buffer)
Stream/river
Lake or pond
Basemap Layer Credits || Pictometry, King County
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
""")
"J
"J
"J
"J"J "J
"J
"J"J
"J"J"J"J
"J
"J"J"J"J
"J"J"J"J"J"J"J"J"J"J"J"J "J"J !<!<!<""")
""")
"J
""")""")""")
""")""")
""")
""")
""")
""")
"J"J"J"J
"J"J
"J"J
"J
"J "J
"J
"J
"J"J
""")
""")""")
""")
""")
""")
""")
""")""")""")
""")
""")
""")
""")
"J"J
"J
"J
"J
""")
""")""")""")
&<&<
!<!<!<""")
""")
NE 4TH ST QUEEN AVE NEMONROE AVE NENE 2ND ST
NE 6TH ST
NE 8TH ST
UNION AVE NE67.29 67.88
8
3.51
10.5
3.5
46
4
3
6
0.5
3030
2438.5
47
7.6
7.5
5
5
6
0.5
8
12
12.5
8
1010
158
9.55
11.5 5
11.5
11.5
4.5
1940
2629
33
Qac
af Qmc
Qac
Qpa
Qgt
Qu
Qu
Qu
Qlp
Qgt
Qgt
QpaGIS Path: T:\projects_8\CityofRenton\MonroeAveNEStormImprovements_190398\Delivered\PreliminarySWFeasibilityEvaluation\Fig 03 Surficial Geologic Units.mxd || Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Feet || Date Saved: 1/9/2020 || User: ecrumbaker || Print Date: 1/9/2020FIGURE NO.3JAN-2020
PROJECT NO.190398
BY:EAC / ETB
REVISED BY:- - -
Surficial Geologic UnitsPreliminary Stormwater Feasibility EvaluationMonroe Avenue NE Storm System ImprovementsCity of Renton, Washington
0 600300
Feet
Explorations from Previous Geotechnical Reports
")Blue Color IndicatesExploration with Infiltration Test
"J Boring_____
!<Hand Auger_____
&<Monitoring Well_____
""")Test Pit_____
Surficial Geology (WADNR 1:24,000)
Quaternary Rocks and Deposits
Quaternary bog, marsh, swamp, or lake deposits
Holocene artificial fill and modified land
Quaternary alluviumQuaternary mass-wastingdeposits
Pleistocene continental glacial driftPleistocene continentalglacial tillPleistocene glacial andnonglacial deposits
Project Boundary
Project Boundary1000-ft Buffer
Basemap Layer Credits || Esri, HERE, Garmin, (c) OpenStreetMap contributors, and the GIS user community
12
11Depth toGroundwater (ft)
Till Depth (ft)(If Observed)
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
NE 4TH ST QUEEN AVE NEMONROE AVE NENE 2ND ST
NE 6TH ST
NE 8TH ST
300
15
0
12
5
100
75
35
0
32
5
275
200175325
27542
5
40
0
400375250225
3004
0
0
4
0
0
35
0
5
3
0
0
300
27530027522550GIS Path: T:\projects_8\CityofRenton\MonroeAveNEStormImprovements_190398\Delivered\PreliminarySWFeasibilityEvaluation\Fig 04 Surface Elevation.mxd || Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Feet || Date Saved: 1/9/2020 || User: ecrumbaker || Print Date: 1/9/2020FIGURE NO.4JAN-2020
PROJECT NO.190398
BY:EAC / ETB
REVISED BY:- - -
Surface ElevationPreliminary Stormwater Feasibility EvaluationMonroe Avenue NE Storm System ImprovementsCity of Renton, Washington
0 600300
Feet
Project Boundary
Project Boundary 1000-ft Buffer
5-ft Contour (City of Renton)
Surface Elevation (King County Lidar, 2016)
Value High : 440.507
Low : 44.2797
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
!\
!\
!\
!\
!\
!\
!\
!\
!\
!\
!\
!\
!\!\
!\
!\
!\!\
!\!\!\
!\
!\
!\
!\
!\
!\
!\
!\
!\
!\
!\!\
!\
!\!\!\!\!\!\
!\
!\
NE 4TH ST QUEEN AVE NEMONROE AVE NENE 2ND ST
NE 6TH ST
NE 8TH ST
UNION AVE NEGIS Path: T:\projects_8\CityofRenton\MonroeAveNEStormImprovements_190398\Delivered\PreliminarySWFeasibilityEvaluation\Fig 05 Critical Areas.mxd || Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Feet || Date Saved: 1/9/2020 || User: ecrumbaker || Print Date: 1/9/2020FIGURE NO.5JAN-2020
PROJECT NO.190398
BY:EAC / ETB
REVISED BY:- - -
Critical AreasPreliminary Stormwater Feasibility EvaluationMonroe Avenue NE Storm System ImprovementsCity of Renton, Washington
0 600300
Feet
!\Facilities (WA Ecology)
Project Boundary
Project Boundary1000-ft Buffer
Wetland (City of Renton)
Classified Streams (City of Renton)
Stream (no Classification)
Wellfield Capture Zones (City of Renton)
Ten Year Capture Zone
Steep Slopes (City of Renton)
Percent Range
>15% & <=25%
>25% & <=40%
>40% & <=90%
High Erosion Hazard Area(City of Renton)
Moderate Landslide Severity(City of Renton)
Basemap Layer Credits || Esri, HERE, Garmin, (c) OpenStreetMap contributors, and the GIS user community
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
NE 4TH ST QUEEN AVE NEMONROE AVE NENE 2ND ST
NE 6TH ST
NE 8TH ST
UNION AVE NEGIS Path: T:\projects_8\CityofRenton\MonroeAveNEStormImprovements_190398\Delivered\PreliminarySWFeasibilityEvaluation\Fig 06 Hazard Areas.mxd || Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Feet || Date Saved: 1/9/2020 || User: ecrumbaker || Print Date: 1/9/2020FIGURE NO.6JAN-2020
PROJECT NO.190398
BY:EAC / ETB
REVISED BY:- - -
Geologic Hazard AreasPreliminary Stormwater Feasibility EvaluationMonroe Avenue NE Storm System ImprovementsCity of Renton, Washington
0 600300
Feet
Geologic Hazard Areas
Low Hazard
Elevated Hazard
Project Boundary
Project Boundary 1000-ft Buffer
Basemap Layer Credits || Esri, HERE, Garmin, (c) OpenStreetMap contributors, and the GIS user community
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
NE 4TH ST QUEEN AVE NEMONROE AVE NENE 2ND ST
NE 6TH ST
NE 8TH ST
Upper Balch Pit
UNION AVE NEGIS Path: T:\projects_8\CityofRenton\MonroeAveNEStormImprovements_190398\Delivered\PreliminarySWFeasibilityEvaluation\Fig 07 Surface Slope.mxd || Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Feet || Date Saved: 1/9/2020 || User: ecrumbaker || Print Date: 1/9/2020FIGURE NO.7JAN-2020
PROJECT NO.190398
BY:EAC / ETB
REVISED BY:- - -
Surface Slope ClassificationPreliminary Stormwater Feasibility EvaluationMonroe Avenue NE Storm System ImprovementsCity of Renton, Washington
0 600300
Feet
Surface Slope Classification
Good: less than 8%
Moderate: 8 - 15 %
Poor: Greater than 15%
Project Boundary
Project Boundary 1000-ft Buffer
Basemap Layer Credits || Esri, HERE, Garmin, (c) OpenStreetMap contributors, and the GIS user community
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
""")
NE 4TH ST QUEEN AVE NEMONROE AVE NENE 2ND ST
NE 6TH ST
NE 8TH ST
UNION AVE NE4.88 1.250.25
33.91 106.56
8.17.7 5.1
150GIS Path: T:\projects_8\CityofRenton\MonroeAveNEStormImprovements_190398\Delivered\PreliminarySWFeasibilityEvaluation\Fig 08 Soil Permeability.mxd || Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Feet || Date Saved: 1/12/2020 || User: ecrumbaker || Print Date: 1/12/2020FIGURE NO.8JAN-2020
PROJECT NO.190398
BY:EAC / ETB
REVISED BY:- - -
Soil PermeabilityPreliminary Stormwater Feasibility EvaluationMonroe Avenue NE Storm System ImprovementsCity of Renton, Washington
0 600300
Feet
Surface Permeabilty
High Permeability
Low Permeability
Project Boundary
Project Boundary 1000-ft Buffer
Explorations with Infiltration Test
""")Test Pit
Basemap Layer Credits || Esri, HERE, Garmin, (c) OpenStreetMap contributors, and the GIS user community
150
Infiltration Rate(in/hr)
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
NE 4TH ST QUEEN AVE NEMONROE AVE NENE 2ND ST
NE 6TH ST
NE 8TH ST
UNION AVE NEGIS Path: T:\projects_8\CityofRenton\MonroeAveNEStormImprovements_190398\Delivered\PreliminarySWFeasibilityEvaluation\Fig 09 Shallow Infiltration Feasibilty.mxd || Coordinate System: NAD 1983 StatePlane Washington North FIPS 4601 Feet || Date Saved: 1/9/2020 || User: ecrumbaker || Print Date: 1/9/2020FIGURE NO.9JAN-2020
PROJECT NO.190398
BY:EAC / ETB
REVISED BY:- - -
Shallow Infiltration FeasibilityPreliminary Stormwater Feasibility Evaluation Monroe Avenue NE Storm System Improvements City of Renton, Washington
0 600300
Feet
Shallow Infiltration Feasibility
Good Potential
Moderate Potential
Poor Potential
Project Boundary
Project Boundary 1000-ft Buffer
Basemap Layer Credits || Esri, HERE, Garmin, (c) OpenStreetMap contributors, and the GIS user community
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
APPENDIX A
Report Limitations
and Guidelines for Use
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
ASPECT CONSULTING
REPORT LIMITATIONS AND GUIDELINES FOR
USE
This Report and Project-Specific Factors
Aspect Consulting, LLC (Aspect) considered a number of unique, project-specific factors
when establishing the Scope of Work for this project and report. You should not rely on
this report if it was:
•Not prepared for you
•Not prepared for the specific purpose identified in the Agreement
•Not prepared for the specific real property assessed
•Completed before important changes occurred concerning the subjectproperty, project or governmental regulatory actions
Geoscience Interpretations
The geoscience practices (geotechnical engineering, geology, and environmental science)
require interpretation of spatial information that can make them less exact than other
engineering and natural science disciplines. It is important to recognize this limitation in
evaluating the content of the report. If you are unclear how these "Report Limitations
and Use Guidelines" apply to your project or site, you should contact Aspect.
Reliance Conditions for Third Parties
This report was prepared for the exclusive use of the Client. No other party may rely on
the product of our services unless we agree in advance to such reliance in writing. This is
to provide our firm with reasonable protection against liability claims by third parties
with whom there would otherwise be no contractual limitations. Within the limitations of
scope, schedule, and budget, our services have been executed in accordance with our
Agreement with the Client and recognized geoscience practices in the same locality and
involving similar conditions at the time this report was prepared.
Property Conditions Change Over Time
This report is based on conditions that existed at the time the study was performed. The
findings and conclusions of this report may be affected by the passage of time, by events
such as a change in property use or occupancy, or by natural events, such as floods,
earthquakes, slope instability, or groundwater fluctuations. If any of the described events
may have occurred following the issuance of the report, you should contact Aspect so
that we may evaluate whether changed conditions affect the continued reliability or
applicability of our conclusions and recommendations.
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
ASPECT CONSULTING
Discipline-Specific Reports Are Not Interchangeable
The equipment, techniques, and personnel used to perform a geotechnical or geologic
study differ significantly from those used to perform an environmental study and vice
versa. For that reason, a geotechnical engineering or geologic report does not usually
address any environmental findings, conclusions, or recommendations (e.g., about the
likelihood of encountering underground storage tanks or regulated contaminants).
Similarly, environmental reports are not used to address geotechnical or geologic
concerns regarding the subject property.
We appreciate the opportunity to perform these services. If you have any questions please
contact the Aspect Project Manager for this project.
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
k:\project\33200\33201a\projectdocs\reports\field work and modeling memo\21_0415 field work and modeling memo.docx
Appendix B – Geotechnical Evaluation for Potential Stormwater Facilities
Technical Memorandum
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C
DocuSign Envelope ID: 00997718-9B11-4D89-AD86-5EF6CC7CC14C