Drainage ReportDrainage and Erosion Control
Report
for
Washington Apartments
Yelm, WA
November 22, 2019
PO Box 12690
Olympia WA 98508
360.705.2474
www.olyeng.com
________________________________________________________________________________
November 2019 Drainage and Erosion Control Report 1
COVER SHEET
WASHINGTON APARTMENTS
Yelm, Washington
November 22, 2019
Owner/Applicant
Prepared for: Tim Fyrst
Contact: Tim Fyrst
PO Box 1276
Yelm, WA 98597
(360) 400-7767
Reviewing Agency
Jurisdiction: City of Yelm, Washington
Project Number: 20180337
Project Contact: Tami Merriman
(360) 458-8496
Contractor
Contact:
References
WSDOE Stormwater Management Manual for Western Washington (SWMMWW),
2014 ed.
Project Engineer
Prepared by: Olympic Engineering, Inc.
PO Box 12690
Olympia, WA 98508
(360) 705-2474
Contact: Chris Merritt, PE
Project Number: 17046
11/22/19
"I hereby certify that this Drainage and Erosion Control Plan and Report
and Construction SWPPP for the Washington Apartments project has
been prepared by me or under my supervision and meets the
requirements of the City of Yelm Stormwater Standards and the
standards of care and expertise which is usual and customary in this
community for professional engineers. I understand that the City of
Tumwater does not and will not assume liability for the sufficiency,
suitability, or performance of drainage facilities prepared by me.”
________________________________________________________________________________
November 2019 Drainage and Erosion Control Report 2
TABLE OF CONTENTS
COVER SHEET ........................................................................................................................ 1
TABLE OF CONTENTS ........................................................................................................... 2
SECTION 1 – PROPOSED PROJECT DESCRIPTION .......................................................... 3
Permit ................................................................................................................................................ 3
Project Location ................................................................................................................................. 3
Property Boundaries & Zoning ........................................................................................................... 3
Project Description ............................................................................................................................. 3
Minimum Requirements ..................................................................................................................... 3
Timing of the Project .......................................................................................................................... 5
SECTION 2 – EXISTING SITE CONDITIONS ......................................................................... 5
Topography ........................................................................................................................................ 5
Ground Cover .................................................................................................................................... 5
Drainage ............................................................................................................................................ 5
Soils ................................................................................................................................................... 5
Critical Areas ..................................................................................................................................... 6
Adjacent Areas .................................................................................................................................. 6
Precipitation Records ......................................................................................................................... 6
Reports and Studies .......................................................................................................................... 6
SECTION 3 – GEOTECHNICAL REPORT .............................................................................. 6
SECTION 4 – WELLS AND SEPTIC SYSTEMS ..................................................................... 6
SECTION 5 – FUEL TANKS .................................................................................................... 6
SECTION 6 – ANALYSIS OF THE 100-YEAR FLOOD .......................................................... 6
SECTION 7 – AESTHETIC CONSIDERATIONS FOR FACILITIES ....................................... 6
SECTION 8 – FACILITY SIZING AND OFF-SITE ANALYSIS ................................................ 7
Proposed Permanent BMP’s ............................................................................................................. 7
Off-Site Analysis ................................................................................................................................ 8
SECTION 9 – COVENANTS, DEDICATIONS, EASEMENTS ................................................ 8
SECTION 10 – PROPERTY OWNERS ASSOCIATION ARTICLES OF INCORPORATION 8
APPENDICES
Appendix 1 - Drainage Plans
Appendix 2 - Drainage Calculations
Appendix 3 - Soils Report
________________________________________________________________________________
November 2019 Drainage and Erosion Control Report 3
SECTION 1 – PROPOSED PROJECT DESCRIPTION
Permit
The applicant is applying for permits to construct two apartment buildings (15 units
total) with associated frontage, private/public utilities, parking lot, grading, and storm
drainage improvements.
Project Location
See Vicinity Map on plans for reference.
Site Address: ______ Washington St. SW
Yelm, WA 98594
Tax Parcel Number(s): 75300901200 & 75300901400
Section, Township, Range: Section 19
Township 17 North
Range 02 East, W.M.
Property Boundaries & Zoning
The zoning is Central Business District (CBD). The parcel boundaries are shown on
the drainage plans (see Appendix).
Project Description
The proposal is to construct two apartment buildings (15 units total) with associated
frontage, private/public utilities, grading, parking lot, and storm drainage
improvements. The project will be completed in one phase. It is anticipated that
construction will begin in spring 2020 with substantial completion by winter
2020/2021. See plans for additional information.
Minimum Requirements
The Minimum Requirements for stormwater development and redevelopment sites
are listed in Section I-2.4 of Volume I of the SWMMWW. The proposed project
creates and/or replaces more than 5,000 square-feet of new hard surface area;
therefore, the proposed project must address Minimum Requirements #1 through #9.
This project will meet the LID Performance Standard and flow control standard as the
majority of stormwater runoff from the new improvements will be infiltrated (see
WWHM output in Appendix).
The Minimum Requirements have been addressed as follows:
Minimum Requirement #1 – Preparation of Stormwater Site Plans
Drainage Plans have been prepared for this project (see Appendix).
Minimum Requirement #2 – Construction Stormwater Pollution Prevention
(SWPP)
A Construction Stormwater Pollution Prevention (SWPP) Plan has been
prepared.
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November 2019 Drainage and Erosion Control Report 4
Minimum Requirement #3 – Source Control of Pollution
A Permanent Source Control Plan will be provided with the storm drainage
maintenance agreement prior to final project approval.
Minimum Requirement #4 – Preservation of Natural Drainage Systems and
Outfalls
There are no existing natural drainage systems or outfalls located on or near
the subject parcel; therefore, this Minimum Requirement is not applicable.
Minimum Requirement #5 – On-Site Stormwater Management
This project will meet the LID Performance Standard as the majority of hard surface
areas are proposed to be infiltrated. The proposed BMP’s are as follows:
Lawn and Landscape Areas:
• All disturbed and/or new lawn and landscape areas will contain soils
meeting the Post-Construction Soil Quality and Depth (BMP T5.13)
requirements.
Roof Areas:
• Stormwater runoff from the roof areas will be tightlined to an Infiltration
Trench (BMP T7.20) consisting of 21 StormTech chambers for storage
and 100% infiltration.
Other Hard Surface Areas:
• Stormwater runoff from the new on-site parking lot and sidewalk areas,
along with one-half of Rice St. and Washington St. will be collected and
tightlined to a Type 2 catch basin containing one Baysaver Bayfilter™
cartridge for runoff treatment. Treated stormwater runoff will be
conveyed to a below-grade infiltration trench (BMP T7.20) consisting of
21 StormTech chambers for storage and 100% infiltration.
See Section 8 and the drainage plans for additional information.
Minimum Requirement #6 – Runoff Treatment
This project will create/replace more than 5,000 square-feet of new total
effective pollution-generating hard surface (PGHS) area; therefore, Runoff
Treatment is required.
See Minimum Requirement #5 above and Section 8 below for additional
information along with the WWHM modeling results in the Appendix for the
15-minute water quality flow rate treatment requirement.
Minimum Requirement #7 – Flow Control
This project will have less than 10,000 square-feet of “effective” impervious
surface area; will convert less than ¾-acre of vegetation to lawn/landscape;
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November 2019 Drainage and Erosion Control Report 5
convert less than 2.5-acres of native vegetation to pasture; and cause less
than a 0.15-cfs increase in the 100-year flow frequency; therefore, additional
Flow Control facilities (above what is proposed) is not required. Per WWHM,
this project will meet the LID Performance Standard and flow control
standard.
See Minimum Requirement #5 above and Section 8 below for additional
information along with the WWHM modeling results in the Appendix for
infiltration trench sizing.
Minimum Requirement #8 – Wetlands Protection
There are no known wetlands located on-site or within the immediate vicinity;
therefore, this Minimum Requirement is not applicable.
Minimum Requirement #9 – Operation and Maintenance
A storm drainage maintenance agreement, including a pollution source
control plan, will be prepared and recorded prior to final project approval.
Optional Guidance #1 – Financial Liability
A Financial Guarantee will be provided prior to final project approval, if
required.
Optional Guidance #2 – Off-Site Analysis and Mitigation
See Section 8 below. No downstream impacts are anticipated as a result of
this project.
Timing of the Project
The project will be completed in one phase. It is anticipated that construction will
begin in summer 2019 with substantial completion by spring 2020.
SECTION 2 – EXISTING SITE CONDITIONS
Topography
Site topography is gentle and rolling generally sloping down towards the west.
Ground Cover
Site vegetation consists mainly of scattered trees (mainly deciduous), scotch broom,
and field grass.
Drainage
See drainage plan and Section 8 below.
Soils
The Natural Resources Conservation Service (NRCS) Soil Survey of Thurston
County classifies the on-site soils as Spanaway Gravelly/Stony Sandy Loam (HSG
A). A Geotechnical Investigation report has been prepared by Materials Testing &
Consulting, dated December 12, 2016 (see Appendix), and this report generally
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November 2019 Drainage and Erosion Control Report 6
confirms the NRCS classification. However, fill material was encountered throughout
the site extending to depths of 2.5 to 3.5-feet. This uncontrolled fill will be removed
as part of site development.
Critical Areas
There are no known critical areas (i.e. wetlands, steep slopes, streams, etc.) located
on-site or within the immediate vicinity of the site based on review of Thurston
County critical areas maps and a site visit.
Adjacent Areas
The project site is bounded by Washington St. to the south, by Rice St. to the west,
by an alley to the north, and by a developed residential parcel to the east.
Precipitation Records
Precipitation data is included within the WWHM model.
Reports and Studies
A Geotechnical Investigation report has been prepared by Materials Testing &
Consulting, dated December 12, 2016 (see Appendix).
SECTION 3 – GEOTECHNICAL REPORT
A Geotechnical Investigation report has been prepared by Materials Testing & Consulting,
dated December 12, 2016 (see Appendix).
SECTION 4 – WELLS AND SEPTIC SYSTEMS
There are no known on-site wells or septic systems located on-site or within the immediate
vicinity of the project site.
SECTION 5 – FUEL TANKS
No fuel tanks were located during a site inspection or during the soils evaluation work.
Olympic Engineering reviewed the latest “LUST” list (Leaking Underground Storage Tank)
and found no listing for the subject site.
SECTION 6 – ANALYSIS OF THE 100-YEAR FLOOD
According to FEMA FIRM #53067C0353E dated October 16, 2012, the project site and
surrounding area is located in Zone X (area outside the 0.2% annual chance floodplain).
SECTION 7 – AESTHETIC CONSIDERATIONS FOR FACILITIES
All storm facilities will be located below-grade. All disturbed pervious areas will be vegetated
and/or landscaped and will contain soils that meet the Post-Construction Soil Quality and
Depth (BMP T5.13) requirements.
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November 2019 Drainage and Erosion Control Report 7
SECTION 8 – FACILITY SIZING AND OFF-SITE ANALYSIS
Parcel Area: 30,005 sf (0.689 ac)
½ R/W Area: 12,382 sf (0.284 ac) (excludes alley area)
Project Area: 42,387 sf (0.973 ac)
Existing Areas
Roadway: 0.119 ac
Pasture: 0.427 ac
Forest: 0.427 ac
Total 0.973 ac
Proposed Areas
Land Coverage Table – Post-Developed
(Acres)
On-Site Off-Site Total
Roadway 0.172 0.172
Sidewalk 0.026 0.016 0.042
Parking Lot 0.144 0.144
Roof 0.206 0.206
Landscaping 0.312 0.096 0.408
Total 0.688 0.284 0.972*
*May not equal Project Area listed above due to rounding when converting from SF to AC
Proposed Permanent BMP’s
The following Permanent BMP’s have been incorporated into the design (see
drainage plans):
1. BMP T5.13 Post-Construction Soil Quality and Depth (all disturbed,
lawn/landscape, and stormwater dispersion areas)
2. BMP T7.20 Infiltration Trench (public roadway and on-site parking
lot and roof areas)
3. Baysaver Bayfilter™ Treatment System (public roadway and on-site parking
lot areas)
Flow Control & Runoff Treatment Facilities
One Baysaver Bayfilter™ cartridge (BFC 30 gpm) will provide treatment of
stormwater runoff from all pollution generating hard surface (PGHS) areas
(roadways & parking lot areas). Per WWHM modeling results, this project is
required to treat a 15-minute water quality flow rate of 0.0626 cfs.
0.0626 cfs / 0.067 cfs/cartridge = 0.93 (Use one 30 gpm cartridge)
The Washington State Department of Ecology issued a “General Use
Level Designation for Basic (TSS) Treatment” for this filter when
using a 30 gpm/cartridge design flow rate (see Appendix).
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November 2019 Drainage and Erosion Control Report 8
Treated stormwater runoff will be conveyed to an underground infiltration
trench system consisting of 21 StormTech chambers.
The Geotechnical Investigation Report prepared by Materials Testing &
Consulting recommends a design infiltration rate of 10”/hr be used. The 4’
high infiltration trench will provide for 1.2’ of freeboard. See WWHM
modeling results in the Appendix for infiltration trench sizing.
At a maximum ponding depth of 2.8’, the facility will draw down in 3.4 hours
(2.8’x12”)/10”/hr = 3.4 hours).
Modeling & Assumptions
• Stormwater runoff from the roadways, sidewalks, parking lot, and roof areas
will be infiltrated. These areas are considered “ineffective” and can be
excluded from the impervious area threshold determination of Minimum
Requirement #7.
• All infiltrated areas can be discounted from WWHM when comparing pre- to
post-developed runoff rates.
• All lawn/landscape areas that meet the Post-Construction Soil Quality and
Depth (BMP T5.13) requirements may be modeled as “pasture”.
For the LID analysis, all areas to be disturbed were modeled as forest.
Off-Site Analysis
The majority of stormwater runoff generated from the new on-site improvements,
along with existing and new improvements associated with one-half of Rice St. and
Washington St., will be infiltrated on-site and the project will meet the LID
Performance Standard. Stormwater runoff from Rice St. and Washington St.
currently sheet flows to adjacent lawn areas. There does not appear to be any
noticeable stormwater run-on from adjacent parcels.
Stormwater from a complete failure of the on-site infiltration system would
temporarily flood the on-site parking lot and then flow onto Washington Ave. No
downstream impacts, including impacts to structures, are anticipated as a result of
this project.
SECTION 9 – COVENANTS, DEDICATIONS, EASEMENTS
No easements are required for the storm drainage system components.
SECTION 10 – PROPERTY OWNERS ASSOCIATION ARTICLES OF INCORPORATION
The property owner will be required to maintain the stormwater system components
located outside of the public right-of-way. The City of Yelm will maintain the
stormwater collection and conveyance components located within the right-of-way.
Appendix 1
Drainage Plans
PO Box 12690Olympia, WA 98508360.705.2474 officewww.olyeng.com CHRIM.MERSTR
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PO Box 12690Olympia, WA 98508360.705.2474 officewww.olyeng.com CHRIM.MERSTR
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RACCEPTABLE FILL MATERIALS: STORMTECH SC-740 CHAMBER SYSTEMS
PLEASE NOTE:
1. THE LISTED AASHTO DESIGNATIONS ARE FOR GRADATIONS ONLY. THE STONE MUST ALSO BE CLEAN, CRUSHED, ANGULAR. FOR EXAMPLE, A SPECIFICATION FOR #4 STONE WOULD STATE: "CLEAN, CRUSHED,
ANGULAR NO. 4 (AASHTO M43) STONE".
2. STORMTECH COMPACTION REQUIREMENTS ARE MET FOR 'A' LOCATION MATERIALS WHEN PLACED AND COMPACTED IN 6" (150 mm) (MAX) LIFTS USING TWO FULL COVERAGES WITH A VIBRATORY COMPACTOR.
3. WHERE INFILTRATION SURFACES MAY BE COMPROMISED BY COMPACTION, FOR STANDARD DESIGN LOAD CONDITIONS, A FLAT SURFACE MAY BE ACHIEVED BY RAKING OR DRAGGING WITHOUT COMPACTION
EQUIPMENT. FOR SPECIAL LOAD DESIGNS, CONTACT STORMTECH FOR COMPACTION REQUIREMENTS.
NOTES:
1. SC-740 CHAMBERS SHALL CONFORM TO THE REQUIREMENTS OF ASTM F2418 "STANDARD SPECIFICATION FOR POLYPROPYLENE (PP) CORRUGATED WALL STORMWATER COLLECTION
CHAMBERS", OR ASTM F2922 "STANDARD SPECIFICATION FOR POLYETHYLENE (PE) CORRUGATED WALL STORMWATER COLLECTION CHAMBERS".
2. SC-740 CHAMBERS SHALL BE DESIGNED IN ACCORDANCE WITH ASTM F2787 "STANDARD PRACTICE FOR STRUCTURAL DESIGN OF THERMOPLASTIC CORRUGATED WALL STORMWATER
COLLECTION CHAMBERS".
3. "ACCEPTABLE FILL MATERIALS" TABLE ABOVE PROVIDES MATERIAL LOCATIONS, DESCRIPTIONS, GRADATIONS, AND COMPACTION REQUIREMENTS FOR FOUNDATION, EMBEDMENT, AND FILL
MATERIALS.
4. THE SITE DESIGN ENGINEER IS RESPONSIBLE FOR ASSESSING THE BEARING RESISTANCE (ALLOWABLE BEARING CAPACITY) OF THE SUBGRADE SOILS AND THE DEPTH OF FOUNDATION STONE
WITH CONSIDERATION FOR THE RANGE OF EXPECTED SOIL MOISTURE CONDITIONS.
5. PERIMETER STONE MUST BE EXTENDED HORIZONTALLY TO THE EXCAVATION WALL FOR BOTH VERTICAL AND SLOPED EXCAVATION WALLS.
6. ONCE LAYER 'C' IS PLACED, ANY SOIL/MATERIAL CAN BE PLACED IN LAYER 'D' UP TO THE FINISHED GRADE. MOST PAVEMENT SUBBASE SOILS CAN BE USED TO REPLACE THE MATERIAL
REQUIREMENTS OF LAYER 'C' OR 'D' AT THE SITE DESIGN ENGINEER'S DISCRETION.
MATERIAL LOCATION DESCRIPTION
AASHTO MATERIAL
CLASSIFICATIONS
COMPACTION / DENSITY
REQUIREMENT
D
FINAL FILL: FILL MATERIAL FOR LAYER 'D' STARTS
FROM THE TOP OF THE 'C' LAYER TO THE BOTTOM
OF FLEXIBLE PAVEMENT OR UNPAVED FINISHED
GRADE ABOVE. NOTE THAT PAVEMENT SUBBASE
MAY BE PART OF THE 'D' LAYER
ANY SOIL/ROCK MATERIALS, NATIVE SOILS, OR PER
ENGINEER'S PLANS. CHECK PLANS FOR PAVEMENT
SUBGRADE REQUIREMENTS.
N/A
PREPARE PER SITE DESIGN ENGINEER'S PLANS.
PAVED INSTALLATIONS MAY HAVE STRINGENT
MATERIAL AND PREPARATION REQUIREMENTS.
C
INITIAL FILL: FILL MATERIAL FOR LAYER 'C'
STARTS FROM THE TOP OF THE EMBEDMENT
STONE ('B' LAYER) TO 18" (450 mm) ABOVE THE
TOP OF THE CHAMBER. NOTE THAT PAVEMENT
SUBBASE MAY BE A PART OF THE 'C' LAYER.
GRANULAR WELL-GRADED SOIL/AGGREGATE MIXTURES, <35%
FINES OR PROCESSED AGGREGATE.
MOST PAVEMENT SUBBASE MATERIALS CAN BE USED IN LIEU
OF THIS LAYER.
AASHTO M145¹
A-1, A-2-4, A-3
OR
AASHTO M43¹
3, 357, 4, 467, 5, 56, 57, 6, 67, 68, 7, 78, 8, 89,
9, 10
BEGIN COMPACTIONS AFTER 12" (300 mm) OF
MATERIAL OVER THE CHAMBERS IS REACHED.
COMPACT ADDITIONAL LAYERS IN 6" (150 mm) MAX
LIFTS TO A MIN. 95% PROCTOR DENSITY FOR
WELL GRADED MATERIAL AND 95% RELATIVE
DENSITY FOR PROCESSED AGGREGATE
MATERIALS. ROLLER GROSS VEHICLE WEIGHT
NOT TO EXCEED 12,000 lbs (53 kN). DYNAMIC
FORCE NOT TO EXCEED 20,000 lbs (89 kN).
B
EMBEDMENT STONE: FILL SURROUNDING THE
CHAMBERS FROM THE FOUNDATION STONE ('A'
LAYER) TO THE 'C' LAYER ABOVE.
CLEAN, CRUSHED, ANGULAR STONE, NOMINAL SIZE
DISTRIBUTION BETWEEN 3/4-2 INCH (20-50 mm)
AASHTO M43¹
3, 357, 4, 467, 5, 56, 57 NO COMPACTION REQUIRED.
A
FOUNDATION STONE: FILL BELOW CHAMBERS
FROM THE SUBGRADE UP TO THE FOOT (BOTTOM)
OF THE CHAMBER.
CLEAN, CRUSHED, ANGULAR STONE, NOMINAL SIZE
DISTRIBUTION BETWEEN 3/4-2 INCH (20-50 mm)
AASHTO M43¹
3, 357, 4, 467, 5, 56, 57
PLATE COMPACT OR ROLL TO ACHIEVE A FLAT
SURFACE. ² ³
18"
(450 mm) MIN*
8'
(2.4 m)
MAX
SUBGRADE SOILS
(SEE NOTE 5)
PAVEMENT LAYER (DESIGNED
BY SITE DESIGN ENGINEER)
SC-740
END CAP
6" (150 mm) MIN
D
C
B
A
PERIMETER STONE
(SEE NOTE 6)
EXCAVATION WALL
(CAN BE SLOPED OR VERTICAL)
12" (300 mm) MIN
ADS GEOSYNTHETICS 601T NON-WOVEN GEOTEXTILE ALL
AROUND CLEAN, CRUSHED, ANGULAR STONE IN A & B LAYERS
12" (300 mm) TYP51" (1295 mm)6"
(150 mm) MIN
30"
(760 mm)
12"
*TO BOTTOM OF FLEXIBLE PAVEMENT. FOR UNPAVED
INSTALLATIONS WHERE RUTTING FROM VEHICLES MAY OCCUR,
INCREASE COVER TO 24" (600 mm).
BOTTOM ELEV. = 340.0
NOTE:
SEE WSDOT STANDARD PLANS B-10.20-01
B-30.90-01 FOR ACCESS AND STEP/LADDER
LOCATION/ORIENTATION AND DETAILS.
BAYSAVER - BAYFILTER DETAIL (CB#1)
NTS
BAYFILTER
48-1 MANHOLE
PROJECT
LOCATION
WATER QUALITY FLOW 0.0626 CFS
DRAINAGE AREA
CARTRIDGE DESIGN FLOW RATE 30 GPM
# BAYFILTER CARTRIDGES 1
TREATED SEDIMENT CAPACITY
CB#1
WASHINGTON APARTMENTS
INSPECTION PORT
12" X 12" ADS N-12 MANIFOLD
WOVEN GEOTEXTILE OVER BEDDING STONE AND UNDERNEATH
CHAMBER FEET FOR SCOUR PROTECTION AT ALL CHAMBER INLET
ROWS
TYPE 2 CATCH BASIN #1
(WITH BAYSAVER
BAYFILTER CARTRIDGE)
FRAME AND COVER (MARKED
"STORM" PER WSDOT STANDARD
PLAN B-30.70-03
12"Ø OUTLET
12"Ø INLET
FRAME & COVER
OVERFLOW STANDPIPE
ELEV.=344.30
A A
SECTION A-A
12"Ø PIPE - OUTLET - 341.63
RIM - ±349.28
12"Ø PIPE - INLET - 344.30
NOTES:
1. INSPECTION PORTS MAY BE CONNECTED THROUGH ANY CHAMBER
CORRUGATION VALLEY
2. ALL SCHEDULE 40 FITTINGS TO BE SOLVENT CEMENTED.
CONNECTION DETAIL
NTS
8"
(200 mm)
4" (100 mm)
SCHED 40 PVC
COUPLING
4" (100 mm)
SCHED 40 PVC
4" (100 mm)
SCHED 40 PVC
CORE 4.5" (114 mm) Ø
HOLE IN CHAMBER
(4.5" HOLE SAW REQ'D)
ANY VALLEY
LOCATION
STORMTECH CHAMBER
4" (100 mm) SCHED 40
SCREW-IN CAP
NYLOPLAST 12" (300 mm)
INLINE DRAIN BODY W/SOLID
HINGED COVER OR GRATE
CONCRETE COLLAR
PAVEMENT
18" (450 mm) MIN WIDTH
8" (200 mm)
MIN THICKNESS
IINSPECTION PORT DETAIL
NTS
Appendix 2
Drainage Calculations
April 2017
GENERAL USE LEVEL DESIGNATON FOR BASIC TREATMENT
For
BaySaver Technologies, LLC BayFilter™ System using BayFilter Cartridge (BFC)
Ecology’s Decision:
1. Based on BaySaver Technologies’ application submissions, Ecology hereby issues a
Basic Treatment General Use Level Designation (GULD) for the BayFilter™.
As a stormwater treatment device for Basic treatment (TSS) removal.
The Basic Treatment GULD is for the BayFilter Cartridge (BFC) and is limited to
the following maximum flow rate:
a. BFC Cartridge maximum flow rate of 0.70 gpm/sq ft
o 30 gpm (0.067 cfs) per cartridge (example dimensions: 28-inches in diameter,
29-inches tall (43 sq ft filter area))
Canisters that provide 0.70 gpm per sq ft filter area, regardless of
dimensions meet this requirement
o Media Blend of Silica Sand, Perlite, and Activated Alumina
2. Ecology approves use of BayFilter™ Cartridges for treatment at the above flow rate
per cartridge. Designers shall calculate the water quality design flow rates using the
following procedures:
Western Washington: For treatment installed upstream of detention or retention,
the water quality design flow rate is the peak 15-minute flow rate as calculated using
the latest version of the Western Washington Hydrology Model or other Ecology-
approved continuous runoff model.
Eastern Washington: For treatment installed upstream of detention or retention,
the water quality design flow rate is the peak 15-minute flow rate as calculated using
one of the three methods described in Chapter 2.2.5 of the Stormwater Management
Manual for Eastern Washington (SWMMEW) or local manual.
Entire State: For treatment installed downstream of detention, the water quality
design flow rate is the full 2-year release rate of the detention facility.
3. The GULD has no expiration date, but it may be amended or revoked by Ecology, and
is subject to the conditions specified below.
Ecology’s Conditions of Use:
BayFilter™ units shall comply with these conditions:
1. Design, assemble, install, operate, and maintain BayFilter™ units in accordance with
BaySaver Technologies’ applicable manuals and documents and the Ecology Decision.
2. Maintenance: The required inspection/maintenance interval for stormwater treatment
devices is often dependent upon the efficiency of the device and the degree of pollutant
loading from a particular drainage basin. Therefore, Ecology does not endorse or
recommend a “one size fits all” maintenance cycle for a particular model/size of
manufactured filter treatment device.
BaySaver recommends that the following be considered during the design
application of the BayFilter Cartridge systems:
o Water Quality Flow Rate
o Anticipated Pollutant Load
o Maintenance Frequency
A BayFilter System tested adjacent to construction activity required maintenance
after 4-months of operation. Monitoring personnel observed construction washout
in the device during the testing period; the construction activity may have resulted
in a shorter maintenance interval.
Ecology has found that pre-treatment device prior to the BayFilter system can
provide a reduction in pollutant loads on these systems, thereby extending the
maintenance interval.
Test results provided to Ecology from other BayFilter Systems, including the above
mentioned system that was evaluated again after construction activities had been
completed, have indicated the BayFilter System typically has longer maintenance
intervals, sometimes exceeding 12-months.
The BayFilter system contains filter fabric that is highly oleophilic (oil absorptive).
When sufficient quantities of oils are present in the runoff, the oil and subsequent
sediment particles may become attached to the fabric. As a result, it may
compromise the maintenance interval of the BayFilter system. Oil control BMP’s
should be installed upstream of BayFilter installations if warranted, and/or the
BayFilter system should be inspected after any known oil spill or release.
Owners/operators must inspect BayFilter systems for a minimum of twelve months
from the start of post-construction operation to determine site-specific
inspection/maintenance schedules and requirements. Owners/operators must
conduct inspections monthly during the wet season, and every other month during
the dry season. (According to the SWMMWW, the wet season in western
Washington is October 1 to April 30. According to SWMMEW, the wet season in
eastern Washington is October 1 to June 30.) After the first year of operation,
owners/operators must conduct inspections based on the findings during the first
year of inspections or the manufacturer’s anticipated maintenance interval,
whichever is more frequent.
Conduct inspections by qualified personnel, follow manufacturer’s guidelines, and
must use methods capable of determining either a decrease in treated effluent
flowrate and/or a decrease in pollutant removal ability.
3. When inspections are performed, the following findings typically serve as maintenance
triggers:
Accumulated vault sediment depths exceed an average of 2 inches, or
Accumulated sediment depths on the tops of the cartridges exceed an average of 0.5
inches, or
Standing water remains in the vault between rain events.
Bypass during storms smaller than the design storm.
Note: If excessive floatables (trash and debris) are present, perform minor
maintenance consisting of gross solids removal, not cartridge replacement.
4. Discharges from the BayFilter™ units shall not cause or contribute to water quality
standards violations in receiving waters.
Applicant: Advanced Drainage Systems - BaySaver
Applicant’s Address: 4640 Trueman Blvd
Hilliard, Ohio 43065
Application Documents:
Technical Evaluation Report BayFilter System, Grandview Place Apartments, Vancouver,
Washington and Appendices A through O (May 18, 2011)
Washington State Department of Ecology Technology Assessment Protocol –
Environmental BayFilter™ Conditional Use Designation Application (March 2007)
BaySaver Technologies, Inc. BayFilter™ System Washington State Technical and Design
Manual, Version 1.1 (December 2006)
Efficiency Assessment of BaySeparator and Bay filter Systems in the Richard Montgomery
High School January 6.2009.
Evaluation of MASWRC Sample Collection, Sample Analysis, and Data Analysis,
December 27, 2008
Letter from Mid-Atlantic Stormwater Research Center to BaySaver Technologies, In.
dated October 22, 2009.
Letter from Mid-Atlantic Stormwater Research Center to BaySaver Technologies, In.
dated November 5, 2009.
Maryland Department of the Environment letter to BaySaver Technologies dated Jan. 13,
2008 regarding approval of BayFilter as a standalone BMP for Stormwater treatment.
NJCAT letter to BaySaver Technologies dated June 18, 2009 regarding Interim
Certification.
Applicant’s Use Level Request:
General use level designation as a basic treatment device in accordance with Ecology’s
Stormwater Management Manual for Western Washington.
Applicant’s Performance Claims:
Removes and retains 80% of TSS based on laboratory testing using Sil-Co-Sil 106 as a
laboratory stimulant.
Removes 42% of dissolved Copper and 38% of dissolved Zinc.
Expected to remove 50% of the influent phosphorus load.
Ecology’s Recommendations:
BaySaver Technologies, Inc. has shown Ecology, through laboratory and field testing, that
the BayFilter™ System using BayFilter Cartridge (BFC) is capable of attaining Ecology’s
Basic Treatment goals.
Findings of Fact:
Based on field testing in Vancouver, WA, at a flow rate less than or equal to 30 gpm per
canister, the BayFilter™ system demonstrated a total suspended solids removal efficiency
of greater than 80% for influent concentrations between 100 and 200 mg/l and an effluent
concentration < 20 mg/l for influent concentration < 100 mg/l.
Based on laboratory testing, at a flowrate of 30 GPM per filter, the BayFilter™ system
demonstrated a total suspended solids removal efficiency of 81.5% using Sil-Co-Sil 106
with an average influent concentration of 268 mg/L and zero initial sediment loading.
Based on laboratory testing, at a flowrate of 30 GPM per filter, the BayFilter™ system
demonstrated a dissolved phosphorus removal efficiency of 55% using data from the
Richard Montgomery High School field-testing. The average influent concentration was
0.31 mg/L phosphorus and zero initial sediment loading.
Based on data from field-testing at Richard Montgomery High School in Rockville, MD
the BayFilter system demonstrated a Cu removal efficiency of 51% and 41% for total and
dissolved Cu respectively. Average influent concentrations are 41.6 µg/l total and 17.5
µg/l dissolved.
Based on data from field-testing at Richard Montgomery High School in Rockville, MD
the BayFilter system demonstrated a Zn removal efficiency of 45% and 38% for total and
dissolved Cu, respectively. Average influent concentrations are 354 µg/l total and 251
µg/l dissolved, respectively.
Other BayFilter™ Related Issues to be Addressed By the Company:
1. BaySaver should continue monitoring the system for a longer period to help establish a
maintenance period and to obtain data from additional qualified storms. Conduct testing to
obtain information about maintenance requirements in order to come up with a maintenance
cycle.
2. Conduct loading tests on the filter to determine maximum treatment life of the system.
3. Conduct testing to determine if oils and grease affect the treatment ability of the filter. This
should include a determination of how oil and grease may affect the ion-exchange capacity of
the system if BaySaver wishes to make claims for phosphorus removal.
4. BaySaver should develop easy-to-implement methods of determining when a BayFilter system
requires maintenance (cleaning and filter replacement).
5. BaySaver must update their O&M documents to include information and instructions on the
“24-hour draw-down” method to determine if cartridges need replacing.
Technology Description: Download at www.BaySaver.com
Contact Information:
Applicant: Daniel Figola
Advanced Drainage Systems - BaySaver
4640 Trueman Blvd
Hilliard, Ohio 43065
(614) 658-0265
dfigola@ads-pipe.com
Applicant website: www.BaySaver.com
Ecology web link: http://www.ecy.wa.gov/programs/wq/stormwater/newtech/index.html
Ecology: Douglas C. Howie, P.E.
Department of Ecology
Water Quality Program
(360) 407-6444
douglas.howie@ecy.wa.gov
Revision History
Date Revision
April 2008 Original use-level-designation document
February 2010 Revision
August 2011 GULD awarded for Basic Treatment
April 2012 Maintenance requirements updated.
August 2012 Revised design storm criteria
December 2012 Revised contact information and document formatting
December 2013 Revised expiration and submittal dates
December 2014 Revised Inspection/maintenance discussion, Updated cartridge
descriptions
January 2015 Revised discussion for flow rate controls
December 2015 Revised Expiration date
January 2016 Revised Manufacturer Contact Information and expiration date
January 2017 Revised Expiration, QAPP and TER due dates
April 2017 Updated to create separate ULDs for the BayFilter™ using BayFilter
Cartridge (BFC) and the BayFilter™ using Enhanced Media Cartridge
(EMC)
Project:
Chamber Model - SC-740
Units -Imperial
Number of chambers -21
Voids in the stone (porosity) - 40 %
Base of Stone Elevation -0.00 ft
Amount of Stone Above Chambers - 6 in
Amount of Stone Below Chambers -12 in
Area of system -841 sf Min. Area -
Height of
System
Incremental Single
Chamber
Incremental
Total Chamber
Incremental
Stone
Incremental Ch
& St
Cumulative
Chamber Elevation
(inches)(cubic feet)(cubic feet)(cubic feet)(cubic feet)(cubic feet)(feet)
48 0.00 0.00 28.05 28.05 1925.28 4.00
47 0.00 0.00 28.05 28.05 1897.24 3.92
46 0.00 0.00 28.05 28.05 1869.19 3.83
45 0.00 0.00 28.05 28.05 1841.14 3.75
44 0.00 0.00 28.05 28.05 1813.09 3.67
43 0.00 0.00 28.05 28.05 1785.04 3.58
42 0.05 1.15 27.59 28.74 1757.00 3.50
41 0.16 3.42 26.68 30.10 1728.26 3.42
40 0.28 5.92 25.68 31.60 1698.15 3.33
39 0.60 12.68 22.97 35.66 1666.55 3.25
38 0.80 16.84 21.31 38.15 1630.90 3.17
37 0.95 19.96 20.06 40.03 1592.75 3.08
36 1.07 22.56 19.02 41.59 1552.72 3.00
35 1.18 24.79 18.13 42.92 1511.13 2.92
34 1.27 26.58 17.42 44.00 1468.21 2.83
33 1.36 28.46 16.67 45.12 1424.22 2.75
32 1.45 30.54 15.83 46.37 1379.09 2.67
31 1.52 32.02 15.24 47.26 1332.73 2.58
30 1.58 33.23 14.76 47.99 1285.47 2.50
29 1.64 34.49 14.25 48.74 1237.48 2.42
28 1.70 35.69 13.77 49.46 1188.74 2.33
27 1.75 36.81 13.32 50.13 1139.28 2.25
26 1.80 37.86 12.90 50.76 1089.14 2.17
25 1.85 38.95 12.47 51.42 1038.38 2.08
24 1.89 39.75 12.15 51.90 986.96 2.00
23 1.93 40.61 11.80 52.42 935.06 1.92
22 1.97 41.47 11.46 52.93 882.64 1.83
21 2.01 42.21 11.16 53.37 829.71 1.75
20 2.04 42.94 10.87 53.81 776.34 1.67
19 2.07 43.57 10.62 54.19 722.52 1.58
18 2.10 44.20 10.37 54.57 668.33 1.50
17 2.13 44.77 10.14 54.91 613.76 1.42
16 2.15 45.23 9.96 55.19 558.85 1.33
15 2.18 45.72 9.76 55.48 503.66 1.25
14 2.20 46.17 9.58 55.75 448.18 1.17
13 2.21 46.35 9.51 55.86 392.44 1.08
Washington Apartments
710 sf min. area
StormTech SC-740 Cumulative Storage Volumes
Include Perimeter Stone in Calculations
12 0.00 0.00 28.05 28.05 336.58 1.00
11 0.00 0.00 28.05 28.05 308.53 0.92
10 0.00 0.00 28.05 28.05 280.48 0.83
9 0.00 0.00 28.05 28.05 252.43 0.75
8 0.00 0.00 28.05 28.05 224.38 0.67
7 0.00 0.00 28.05 28.05 196.34 0.58
6 0.00 0.00 28.05 28.05 168.29 0.50
5 0.00 0.00 28.05 28.05 140.24 0.42
4 0.00 0.00 28.05 28.05 112.19 0.33
3 0.00 0.00 28.05 28.05 84.14 0.25
2 0.00 0.00 28.05 28.05 56.10 0.17
1 0.00 0.00 28.05 28.05 28.05 0.08
Orifice 1 0 0
Orifice 2 0 0
Orifice 3 0 0
NOTE: If system height is greater than 15 ft
contact ADS Technical Services at (860) 257-2151
To Be Copied as SSD Table (copy to new spreadhseet and save as csv file)
Stage
(ft)
Area
(acres)
Storage
(ac-ft)
Dis
(cfs)Infil
0.000 0.019317 0.000000 0.000
0.083 0.019317 0.000644 0.000
0.167 0.019317 0.001288 0.000
0.250 0.019317 0.001932 0.000
0.333 0.019317 0.002576 0.000
0.417 0.019317 0.003219 0.000
0.500 0.019317 0.003863 0.000
0.583 0.019317 0.004507 0.000
0.667 0.019317 0.005151 0.000
0.750 0.019317 0.005795 0.000
0.833 0.019317 0.006439 0.000
0.917 0.019317 0.007083 0.000
1.000 0.019317 0.007727 0.000
1.083 0.019317 0.009009 0.000
1.167 0.019317 0.010289 0.000
1.250 0.019317 0.011563 0.000
1.333 0.019317 0.012829 0.000
1.417 0.019317 0.014090 0.000
1.500 0.019317 0.015343 0.000
1.583 0.019317 0.016587 0.000
1.667 0.019317 0.017822 0.000
1.750 0.019317 0.019047 0.000
1.833 0.019317 0.020263 0.000
1.917 0.019317 0.021466 0.000
2.000 0.019317 0.022657 0.000
2.083 0.019317 0.023838 0.000
2.167 0.019317 0.025003 0.000
2.250 0.019317 0.026154 0.000
2.333 0.019317 0.027290 0.000
2.417 0.019317 0.028409 0.000
2.500 0.019317 0.029510 0.000
2.583 0.019317 0.030595 0.000
2.667 0.019317 0.031660 0.000
2.750 0.019317 0.032696 0.000
2.833 0.019317 0.033705 0.000
2.917 0.019317 0.034691 0.000
3.000 0.019317 0.035646 0.000
* Note use whole numbers -
Invert to be entered as height
from bottom of system in inches
Orifice
Diameter*
(in)
Invert*
(in)
Click here for MC-3500 and
MC-4500 Chambers
3.083 0.019317 0.036564 0.000
3.167 0.019317 0.037440 0.000
3.250 0.019317 0.038259 0.000
3.333 0.019317 0.038984 0.000
3.417 0.019317 0.039675 0.000
3.500 0.019317 0.040335 0.000
3.583 0.019317 0.041 0.000
3.667 0.019317 0.042 0.000
3.750 0.019317 0.042 0.000
3.833 0.019317 0.043 0.000
3.917 0.019317 0.044 0.000
4.000 0.019317 0.044 0.000
WWHM2012
PROJECT REPORT
112219 WWHM 11/22/2019 12:12:51 PM Page 2
General Model Information
Project Name:112219 WWHM
Site Name:Washington Apartments
Site Address:__Washington St.
City:Yelm
Report Date:11/22/2019
Gage:Lake Lawrence
Data Start:1955/10/01
Data End:2008/09/30
Timestep:15 Minute
Precip Scale:0.857
Version Date:2018/10/10
Version:4.2.16
POC Thresholds
Low Flow Threshold for POC1:50 Percent of the 2 Year
High Flow Threshold for POC1:50 Year
Low Flow Threshold for POC2:50 Percent of the 2 Year
High Flow Threshold for POC2:50 Year
112219 WWHM 11/22/2019 12:12:51 PM Page 3
Landuse Basin Data
Predeveloped Land Use
Basin 1
Bypass:No
GroundWater:No
Pervious Land Use acre
A B, Forest, Flat 0.772
A B, Forest, Mod 0.082
Pervious Total 0.854
Impervious Land Use acre
ROADS FLAT 0.119
Impervious Total 0.119
Basin Total 0.973
Element Flows To:
Surface Interflow Groundwater
112219 WWHM 11/22/2019 12:12:51 PM Page 4
Water Quality "dummy" basin
Bypass:No
GroundWater:No
Pervious Land Use acre
Pervious Total 0
Impervious Land Use acre
ROADS FLAT 0.172
SIDEWALKS FLAT 0.036
SIDEWALKS MOD 0.006
PARKING FLAT 0.091
PARKING MOD 0.053
Impervious Total 0.358
Basin Total 0.358
Element Flows To:
Surface Interflow Groundwater
112219 WWHM 11/22/2019 12:12:51 PM Page 5
Mitigated Land Use
Basin 1
Bypass:No
GroundWater:No
Pervious Land Use acre
Pervious Total 0
Impervious Land Use acre
ROADS FLAT 0.172
ROOF TOPS FLAT 0.206
SIDEWALKS FLAT 0.036
SIDEWALKS MOD 0.006
PARKING FLAT 0.091
PARKING MOD 0.053
Impervious Total 0.564
Basin Total 0.564
Element Flows To:
Surface Interflow Groundwater
SSD Table 1 SSD Table 1
112219 WWHM 11/22/2019 12:12:51 PM Page 6
Landscaping
Bypass:Yes
GroundWater:No
Pervious Land Use acre
A B, Pasture, Flat 0.386
A B, Pasture, Mod 0.023
Pervious Total 0.409
Impervious Land Use acre
Impervious Total 0
Basin Total 0.409
Element Flows To:
Surface Interflow Groundwater
112219 WWHM 11/22/2019 12:12:51 PM Page 7
Water Quality
Bypass:No
GroundWater:No
Pervious Land Use acre
Pervious Total 0
Impervious Land Use acre
ROADS FLAT 0.172
SIDEWALKS FLAT 0.036
SIDEWALKS MOD 0.006
PARKING FLAT 0.091
PARKING MOD 0.053
Impervious Total 0.358
Basin Total 0.358
Element Flows To:
Surface Interflow Groundwater
112219 WWHM 11/22/2019 12:12:51 PM Page 8
Routing Elements
Predeveloped Routing
112219 WWHM 11/22/2019 12:12:51 PM Page 9
Mitigated Routing
SSD Table 1
Depth:4 ft.
Discharge Structure: 1
Riser Height:3 ft.
Riser Diameter:6 in.
Element Flows To:
Outlet 1 Outlet 2
SSD Table Hydraulic Table
Stage Area Volume Outlet Infilt
(feet) (ac.) (ac-ft.) Struct (cfs) NotUsed NotUsed NotUsed
0.000 0.019 0.000 0.000 0.195 0.000 0.000 0.000
0.083 0.019 0.001 0.000 0.195 0.000 0.000 0.000
0.167 0.019 0.001 0.000 0.195 0.000 0.000 0.000
0.250 0.019 0.002 0.000 0.195 0.000 0.000 0.000
0.333 0.019 0.003 0.000 0.195 0.000 0.000 0.000
0.417 0.019 0.003 0.000 0.195 0.000 0.000 0.000
0.500 0.019 0.004 0.000 0.195 0.000 0.000 0.000
0.583 0.019 0.005 0.000 0.195 0.000 0.000 0.000
0.667 0.019 0.005 0.000 0.195 0.000 0.000 0.000
0.750 0.019 0.006 0.000 0.195 0.000 0.000 0.000
0.833 0.019 0.006 0.000 0.195 0.000 0.000 0.000
0.917 0.019 0.007 0.000 0.195 0.000 0.000 0.000
1.000 0.019 0.008 0.000 0.195 0.000 0.000 0.000
1.083 0.019 0.009 0.000 0.195 0.000 0.000 0.000
1.167 0.019 0.010 0.000 0.195 0.000 0.000 0.000
1.250 0.019 0.012 0.000 0.195 0.000 0.000 0.000
1.333 0.019 0.013 0.000 0.195 0.000 0.000 0.000
1.417 0.019 0.014 0.000 0.195 0.000 0.000 0.000
1.500 0.019 0.015 0.000 0.195 0.000 0.000 0.000
1.583 0.019 0.017 0.000 0.195 0.000 0.000 0.000
1.667 0.019 0.018 0.000 0.195 0.000 0.000 0.000
1.750 0.019 0.019 0.000 0.195 0.000 0.000 0.000
1.833 0.019 0.020 0.000 0.195 0.000 0.000 0.000
1.917 0.019 0.021 0.000 0.195 0.000 0.000 0.000
2.000 0.019 0.023 0.000 0.195 0.000 0.000 0.000
2.083 0.019 0.024 0.000 0.195 0.000 0.000 0.000
2.167 0.019 0.025 0.000 0.195 0.000 0.000 0.000
2.250 0.019 0.026 0.000 0.195 0.000 0.000 0.000
2.333 0.019 0.027 0.000 0.195 0.000 0.000 0.000
2.417 0.019 0.028 0.000 0.195 0.000 0.000 0.000
2.500 0.019 0.030 0.000 0.195 0.000 0.000 0.000
2.583 0.019 0.031 0.000 0.195 0.000 0.000 0.000
2.667 0.019 0.032 0.000 0.195 0.000 0.000 0.000
2.750 0.019 0.033 0.000 0.195 0.000 0.000 0.000
2.833 0.019 0.034 0.000 0.195 0.000 0.000 0.000
2.917 0.019 0.035 0.000 0.195 0.000 0.000 0.000
3.000 0.019 0.036 0.000 0.195 0.000 0.000 0.000
3.083 0.019 0.037 0.124 0.195 0.000 0.000 0.000
3.167 0.019 0.037 0.298 0.195 0.000 0.000 0.000
3.250 0.019 0.038 0.389 0.195 0.000 0.000 0.000
3.333 0.019 0.039 0.455 0.195 0.000 0.000 0.000
3.417 0.019 0.040 0.508 0.195 0.000 0.000 0.000
112219 WWHM 11/22/2019 12:12:51 PM Page 10
3.500 0.019 0.040 0.557 0.195 0.000 0.000 0.000
3.583 0.019 0.041 0.601 0.195 0.000 0.000 0.000
3.667 0.019 0.042 0.643 0.195 0.000 0.000 0.000
3.750 0.019 0.042 0.682 0.195 0.000 0.000 0.000
3.833 0.019 0.043 0.719 0.195 0.000 0.000 0.000
3.917 0.019 0.044 0.754 0.195 0.000 0.000 0.000
4.000 0.019 0.044 0.787 0.195 0.000 0.000 0.000
112219 WWHM 11/22/2019 12:12:51 PM Page 11
Analysis Results
POC 1
+ Predeveloped x Mitigated
Predeveloped Landuse Totals for POC #1
Total Pervious Area:0.854
Total Impervious Area:0.119
Mitigated Landuse Totals for POC #1
Total Pervious Area:0.409
Total Impervious Area:0.564
Flow Frequency Method:Log Pearson Type III 17B
Flow Frequency Return Periods for Predeveloped. POC #1
Return Period Flow(cfs)
2 year 0.050677
5 year 0.071083
10 year 0.086745
25 year 0.109154
50 year 0.127866
100 year 0.148409
Flow Frequency Return Periods for Mitigated. POC #1
Return Period Flow(cfs)
2 year 0.001711
5 year 0.006094
10 year 0.012344
25 year 0.027068
50 year 0.045769
100 year 0.074312
Annual Peaks
112219 WWHM 11/22/2019 12:13:46 PM Page 12
Annual Peaks for Predeveloped and Mitigated. POC #1
Year Predeveloped Mitigated
1956 0.043 0.004
1957 0.070 0.005
1958 0.051 0.002
1959 0.048 0.002
1960 0.068 0.001
1961 0.035 0.003
1962 0.038 0.000
1963 0.067 0.006
1964 0.049 0.001
1965 0.049 0.003
1966 0.041 0.000
1967 0.047 0.002
1968 0.031 0.000
1969 0.032 0.000
1970 0.038 0.000
1971 0.036 0.005
1972 0.052 0.009
1973 0.037 0.001
1974 0.075 0.002
1975 0.051 0.001
1976 0.043 0.001
1977 0.063 0.000
1978 0.051 0.004
1979 0.066 0.000
1980 0.038 0.001
1981 0.061 0.005
1982 0.051 0.003
1983 0.090 0.001
1984 0.048 0.001
1985 0.045 0.000
1986 0.062 0.004
1987 0.045 0.004
1988 0.026 0.000
1989 0.033 0.000
1990 0.125 0.018
1991 0.062 0.006
1992 0.049 0.000
1993 0.030 0.000
1994 0.043 0.000
1995 0.066 0.005
1996 0.068 0.008
1997 0.051 0.008
1998 0.077 0.011
1999 0.043 0.000
2000 0.050 0.001
2001 0.045 0.000
2002 0.051 0.003
2003 0.036 0.001
2004 0.158 0.074
2005 0.140 0.035
2006 0.101 0.029
2007 0.070 0.015
2008 0.069 0.004
Ranked Annual Peaks
Ranked Annual Peaks for Predeveloped and Mitigated. POC #1
112219 WWHM 11/22/2019 12:13:46 PM Page 13
Rank Predeveloped Mitigated
1 0.1583 0.0742
2 0.1397 0.0347
3 0.1252 0.0290
4 0.1011 0.0176
5 0.0897 0.0146
6 0.0767 0.0115
7 0.0753 0.0093
8 0.0699 0.0085
9 0.0696 0.0078
10 0.0695 0.0064
11 0.0684 0.0062
12 0.0684 0.0053
13 0.0671 0.0051
14 0.0664 0.0046
15 0.0660 0.0045
16 0.0625 0.0043
17 0.0622 0.0042
18 0.0618 0.0040
19 0.0610 0.0038
20 0.0519 0.0035
21 0.0512 0.0034
22 0.0507 0.0033
23 0.0507 0.0030
24 0.0507 0.0029
25 0.0506 0.0022
26 0.0505 0.0021
27 0.0500 0.0019
28 0.0493 0.0017
29 0.0488 0.0014
30 0.0485 0.0014
31 0.0478 0.0010
32 0.0476 0.0009
33 0.0466 0.0009
34 0.0454 0.0009
35 0.0449 0.0009
36 0.0448 0.0007
37 0.0434 0.0005
38 0.0433 0.0005
39 0.0432 0.0005
40 0.0430 0.0004
41 0.0414 0.0004
42 0.0384 0.0003
43 0.0382 0.0003
44 0.0377 0.0003
45 0.0371 0.0003
46 0.0359 0.0003
47 0.0358 0.0003
48 0.0351 0.0003
49 0.0329 0.0003
50 0.0322 0.0003
51 0.0307 0.0003
52 0.0296 0.0003
53 0.0259 0.0003
112219 WWHM 11/22/2019 12:13:46 PM Page 14
LID Duration Flows
The Facility PASSED
Flow(cfs)Predev Mit Percentage Pass/Fail
0.0041 75231 36 0 Pass
0.0043 71309 34 0 Pass
0.0045 67704 31 0 Pass
0.0047 64284 29 0 Pass
0.0049 61032 27 0 Pass
0.0051 57984 26 0 Pass
0.0053 55085 24 0 Pass
0.0056 52427 24 0 Pass
0.0058 49844 23 0 Pass
0.0060 47465 22 0 Pass
0.0062 45235 18 0 Pass
0.0064 43116 17 0 Pass
0.0066 41109 17 0 Pass
0.0068 39158 14 0 Pass
0.0071 37299 14 0 Pass
0.0073 35664 13 0 Pass
0.0075 34066 13 0 Pass
0.0077 32523 13 0 Pass
0.0079 31092 12 0 Pass
0.0081 29810 11 0 Pass
0.0084 28583 11 0 Pass
0.0086 27412 9 0 Pass
0.0088 26297 9 0 Pass
0.0090 25219 9 0 Pass
0.0092 24160 9 0 Pass
0.0094 23194 8 0 Pass
0.0096 22171 8 0 Pass
0.0099 21279 8 0 Pass
0.0101 20369 8 0 Pass
0.0103 19625 7 0 Pass
0.0105 18845 7 0 Pass
0.0107 18109 7 0 Pass
0.0109 17380 7 0 Pass
0.0111 16639 7 0 Pass
0.0114 15972 7 0 Pass
0.0116 15358 6 0 Pass
0.0118 14792 6 0 Pass
0.0120 14234 6 0 Pass
0.0122 13745 6 0 Pass
0.0124 13229 6 0 Pass
0.0127 12714 6 0 Pass
0.0129 12270 6 0 Pass
0.0131 11788 6 0 Pass
0.0133 11381 6 0 Pass
0.0135 10987 6 0 Pass
0.0137 10567 6 0 Pass
0.0139 10166 6 0 Pass
0.0142 9802 6 0 Pass
0.0144 9422 6 0 Pass
0.0146 9132 5 0 Pass
0.0148 8789 5 0 Pass
0.0150 8454 5 0 Pass
0.0152 8142 5 0 Pass
112219 WWHM 11/22/2019 12:13:46 PM Page 15
0.0154 7884 5 0 Pass
0.0157 7601 5 0 Pass
0.0159 7332 5 0 Pass
0.0161 7060 5 0 Pass
0.0163 6826 5 0 Pass
0.0165 6572 5 0 Pass
0.0167 6341 5 0 Pass
0.0170 6103 5 0 Pass
0.0172 5889 5 0 Pass
0.0174 5653 5 0 Pass
0.0176 5469 5 0 Pass
0.0178 5263 4 0 Pass
0.0180 5038 4 0 Pass
0.0182 4854 4 0 Pass
0.0185 4698 4 0 Pass
0.0187 4535 4 0 Pass
0.0189 4366 4 0 Pass
0.0191 4230 4 0 Pass
0.0193 4092 4 0 Pass
0.0195 3946 3 0 Pass
0.0197 3827 3 0 Pass
0.0200 3689 3 0 Pass
0.0202 3570 3 0 Pass
0.0204 3468 3 0 Pass
0.0206 3351 3 0 Pass
0.0208 3239 3 0 Pass
0.0210 3124 3 0 Pass
0.0213 3022 3 0 Pass
0.0215 2933 3 0 Pass
0.0217 2808 3 0 Pass
0.0219 2697 3 0 Pass
0.0221 2615 3 0 Pass
0.0223 2541 3 0 Pass
0.0225 2462 3 0 Pass
0.0228 2383 3 0 Pass
0.0230 2303 3 0 Pass
0.0232 2228 3 0 Pass
0.0234 2145 3 0 Pass
0.0236 2068 3 0 Pass
0.0238 2013 3 0 Pass
0.0240 1963 3 0 Pass
0.0243 1897 3 0 Pass
0.0245 1840 3 0 Pass
0.0247 1788 3 0 Pass
0.0249 1745 3 0 Pass
0.0251 1685 3 0 Pass
0.0253 1632 3 0 Pass
112219 WWHM 11/22/2019 12:14:02 PM Page 16
Duration Flows
The Facility PASSED
Flow(cfs)Predev Mit Percentage Pass/Fail
0.0253 1632 3 0 Pass
0.0264 1388 3 0 Pass
0.0274 1216 3 0 Pass
0.0284 1064 3 0 Pass
0.0295 923 2 0 Pass
0.0305 816 2 0 Pass
0.0316 721 2 0 Pass
0.0326 640 2 0 Pass
0.0336 551 2 0 Pass
0.0347 485 2 0 Pass
0.0357 434 1 0 Pass
0.0367 393 1 0 Pass
0.0378 340 1 0 Pass
0.0388 303 1 0 Pass
0.0398 270 1 0 Pass
0.0409 241 1 0 Pass
0.0419 209 1 0 Pass
0.0429 188 1 0 Pass
0.0440 160 1 0 Pass
0.0450 145 1 0 Pass
0.0461 134 1 0 Pass
0.0471 118 1 0 Pass
0.0481 108 1 0 Pass
0.0492 94 1 1 Pass
0.0502 83 1 1 Pass
0.0512 70 1 1 Pass
0.0523 67 1 1 Pass
0.0533 61 1 1 Pass
0.0543 56 1 1 Pass
0.0554 52 1 1 Pass
0.0564 47 1 2 Pass
0.0574 45 1 2 Pass
0.0585 39 1 2 Pass
0.0595 34 1 2 Pass
0.0605 34 1 2 Pass
0.0616 28 1 3 Pass
0.0626 25 1 4 Pass
0.0637 24 1 4 Pass
0.0647 24 1 4 Pass
0.0657 23 1 4 Pass
0.0668 20 1 5 Pass
0.0678 16 1 6 Pass
0.0688 13 1 7 Pass
0.0699 11 1 9 Pass
0.0709 10 1 10 Pass
0.0719 9 1 11 Pass
0.0730 8 1 12 Pass
0.0740 8 1 12 Pass
0.0750 8 0 0 Pass
0.0761 7 0 0 Pass
0.0771 6 0 0 Pass
0.0782 6 0 0 Pass
0.0792 6 0 0 Pass
112219 WWHM 11/22/2019 12:14:02 PM Page 17
0.0802 6 0 0 Pass
0.0813 5 0 0 Pass
0.0823 5 0 0 Pass
0.0833 5 0 0 Pass
0.0844 5 0 0 Pass
0.0854 5 0 0 Pass
0.0864 5 0 0 Pass
0.0875 5 0 0 Pass
0.0885 5 0 0 Pass
0.0895 5 0 0 Pass
0.0906 4 0 0 Pass
0.0916 4 0 0 Pass
0.0927 4 0 0 Pass
0.0937 4 0 0 Pass
0.0947 4 0 0 Pass
0.0958 4 0 0 Pass
0.0968 4 0 0 Pass
0.0978 4 0 0 Pass
0.0989 4 0 0 Pass
0.0999 4 0 0 Pass
0.1009 4 0 0 Pass
0.1020 3 0 0 Pass
0.1030 3 0 0 Pass
0.1040 3 0 0 Pass
0.1051 3 0 0 Pass
0.1061 3 0 0 Pass
0.1072 3 0 0 Pass
0.1082 3 0 0 Pass
0.1092 3 0 0 Pass
0.1103 3 0 0 Pass
0.1113 3 0 0 Pass
0.1123 3 0 0 Pass
0.1134 3 0 0 Pass
0.1144 3 0 0 Pass
0.1154 3 0 0 Pass
0.1165 3 0 0 Pass
0.1175 3 0 0 Pass
0.1185 3 0 0 Pass
0.1196 3 0 0 Pass
0.1206 3 0 0 Pass
0.1217 3 0 0 Pass
0.1227 3 0 0 Pass
0.1237 3 0 0 Pass
0.1248 3 0 0 Pass
0.1258 2 0 0 Pass
0.1268 2 0 0 Pass
0.1279 2 0 0 Pass
112219 WWHM 11/22/2019 12:14:02 PM Page 18
Water Quality
Water Quality BMP Flow and Volume for POC #1
On-line facility volume:0 acre-feet
On-line facility target flow:0 cfs.
Adjusted for 15 min:0 cfs.
Off-line facility target flow:0 cfs.
Adjusted for 15 min:0 cfs.
112219 WWHM 11/22/2019 12:14:02 PM Page 19
LID Report
112219 WWHM 11/22/2019 12:14:36 PM Page 20
POC 2
+ Predeveloped x Mitigated
Predeveloped Landuse Totals for POC #2
Total Pervious Area:0
Total Impervious Area:0.358
Mitigated Landuse Totals for POC #2
Total Pervious Area:0
Total Impervious Area:0.358
Flow Frequency Method:Log Pearson Type III 17B
Flow Frequency Return Periods for Predeveloped. POC #2
Return Period Flow(cfs)
2 year 0.15511
5 year 0.211097
10 year 0.252224
25 year 0.308995
50 year 0.354903
100 year 0.40402
Flow Frequency Return Periods for Mitigated. POC #2
Return Period Flow(cfs)
2 year 0.15511
5 year 0.211097
10 year 0.252224
25 year 0.308995
50 year 0.354903
100 year 0.40402
Annual Peaks
Annual Peaks for Predeveloped and Mitigated. POC #2
Year Predeveloped Mitigated
112219 WWHM 11/22/2019 12:15:34 PM Page 21
1956 0.120 0.120
1957 0.220 0.220
1958 0.156 0.156
1959 0.148 0.148
1960 0.211 0.211
1961 0.114 0.114
1962 0.118 0.118
1963 0.206 0.206
1964 0.152 0.152
1965 0.152 0.152
1966 0.126 0.126
1967 0.146 0.146
1968 0.097 0.097
1969 0.101 0.101
1970 0.118 0.118
1971 0.110 0.110
1972 0.139 0.139
1973 0.115 0.115
1974 0.248 0.248
1975 0.159 0.159
1976 0.136 0.136
1977 0.195 0.195
1978 0.157 0.157
1979 0.205 0.205
1980 0.114 0.114
1981 0.192 0.192
1982 0.158 0.158
1983 0.283 0.283
1984 0.148 0.148
1985 0.139 0.139
1986 0.190 0.190
1987 0.139 0.139
1988 0.081 0.081
1989 0.102 0.102
1990 0.373 0.373
1991 0.191 0.191
1992 0.154 0.154
1993 0.091 0.091
1994 0.137 0.137
1995 0.206 0.206
1996 0.184 0.184
1997 0.159 0.159
1998 0.240 0.240
1999 0.134 0.134
2000 0.163 0.163
2001 0.140 0.140
2002 0.158 0.158
2003 0.112 0.112
2004 0.357 0.357
2005 0.416 0.416
2006 0.216 0.216
2007 0.174 0.174
2008 0.212 0.212
Ranked Annual Peaks
Ranked Annual Peaks for Predeveloped and Mitigated. POC #2
Rank Predeveloped Mitigated
1 0.4158 0.4158
112219 WWHM 11/22/2019 12:15:34 PM Page 22
2 0.3727 0.3727
3 0.3567 0.3567
4 0.2833 0.2833
5 0.2478 0.2478
6 0.2403 0.2403
7 0.2203 0.2203
8 0.2164 0.2164
9 0.2119 0.2119
10 0.2114 0.2114
11 0.2063 0.2063
12 0.2056 0.2056
13 0.2052 0.2052
14 0.1951 0.1951
15 0.1922 0.1922
16 0.1908 0.1908
17 0.1898 0.1898
18 0.1838 0.1838
19 0.1737 0.1737
20 0.1632 0.1632
21 0.1593 0.1593
22 0.1585 0.1585
23 0.1583 0.1583
24 0.1580 0.1580
25 0.1568 0.1568
26 0.1562 0.1562
27 0.1538 0.1538
28 0.1522 0.1522
29 0.1520 0.1520
30 0.1483 0.1483
31 0.1476 0.1476
32 0.1455 0.1455
33 0.1403 0.1403
34 0.1393 0.1393
35 0.1393 0.1393
36 0.1387 0.1387
37 0.1374 0.1374
38 0.1361 0.1361
39 0.1339 0.1339
40 0.1261 0.1261
41 0.1201 0.1201
42 0.1180 0.1180
43 0.1180 0.1180
44 0.1151 0.1151
45 0.1143 0.1143
46 0.1139 0.1139
47 0.1115 0.1115
48 0.1104 0.1104
49 0.1021 0.1021
50 0.1011 0.1011
51 0.0970 0.0970
52 0.0909 0.0909
53 0.0809 0.0809
112219 WWHM 11/22/2019 12:15:34 PM Page 23
LID Duration Flows
The Facility PASSED
Flow(cfs)Predev Mit Percentage Pass/Fail
0.0124 73614 73614 100 Pass
0.0131 69730 69730 100 Pass
0.0137 66106 66106 100 Pass
0.0144 62705 62705 100 Pass
0.0150 59452 59452 100 Pass
0.0157 56516 56516 100 Pass
0.0164 53654 53654 100 Pass
0.0170 50996 50996 100 Pass
0.0177 48506 48506 100 Pass
0.0183 46164 46164 100 Pass
0.0190 43953 43953 100 Pass
0.0196 41853 41853 100 Pass
0.0203 39771 39771 100 Pass
0.0210 37894 37894 100 Pass
0.0216 36147 36147 100 Pass
0.0223 34530 34530 100 Pass
0.0229 32913 32913 100 Pass
0.0236 31482 31482 100 Pass
0.0243 30107 30107 100 Pass
0.0249 28825 28825 100 Pass
0.0256 27654 27654 100 Pass
0.0262 26520 26520 100 Pass
0.0269 25387 25387 100 Pass
0.0275 24309 24309 100 Pass
0.0282 23231 23231 100 Pass
0.0289 22246 22246 100 Pass
0.0295 21354 21354 100 Pass
0.0302 20443 20443 100 Pass
0.0308 19644 19644 100 Pass
0.0315 18845 18845 100 Pass
0.0322 18087 18087 100 Pass
0.0328 17347 17347 100 Pass
0.0335 16631 16631 100 Pass
0.0341 15938 15938 100 Pass
0.0348 15340 15340 100 Pass
0.0354 14749 14749 100 Pass
0.0361 14230 14230 100 Pass
0.0368 13634 13634 100 Pass
0.0374 13106 13106 100 Pass
0.0381 12600 12600 100 Pass
0.0387 12138 12138 100 Pass
0.0394 11719 11719 100 Pass
0.0400 11290 11290 100 Pass
0.0407 10866 10866 100 Pass
0.0414 10435 10435 100 Pass
0.0420 10017 10017 100 Pass
0.0427 9671 9671 100 Pass
0.0433 9320 9320 100 Pass
0.0440 8978 8978 100 Pass
0.0447 8647 8647 100 Pass
0.0453 8318 8318 100 Pass
0.0460 8038 8038 100 Pass
0.0466 7763 7763 100 Pass
112219 WWHM 11/22/2019 12:15:34 PM Page 24
0.0473 7499 7499 100 Pass
0.0479 7177 7177 100 Pass
0.0486 6938 6938 100 Pass
0.0493 6711 6711 100 Pass
0.0499 6458 6458 100 Pass
0.0506 6226 6226 100 Pass
0.0512 6005 6005 100 Pass
0.0519 5785 5785 100 Pass
0.0525 5562 5562 100 Pass
0.0532 5338 5338 100 Pass
0.0539 5129 5129 100 Pass
0.0545 4919 4919 100 Pass
0.0552 4761 4761 100 Pass
0.0558 4592 4592 100 Pass
0.0565 4444 4444 100 Pass
0.0572 4282 4282 100 Pass
0.0578 4135 4135 100 Pass
0.0585 3972 3972 100 Pass
0.0591 3832 3832 100 Pass
0.0598 3708 3708 100 Pass
0.0604 3602 3602 100 Pass
0.0611 3496 3496 100 Pass
0.0618 3379 3379 100 Pass
0.0624 3271 3271 100 Pass
0.0631 3165 3165 100 Pass
0.0637 3042 3042 100 Pass
0.0644 2936 2936 100 Pass
0.0651 2838 2838 100 Pass
0.0657 2738 2738 100 Pass
0.0664 2658 2658 100 Pass
0.0670 2565 2565 100 Pass
0.0677 2487 2487 100 Pass
0.0683 2401 2401 100 Pass
0.0690 2308 2308 100 Pass
0.0697 2232 2232 100 Pass
0.0703 2158 2158 100 Pass
0.0710 2089 2089 100 Pass
0.0716 2022 2022 100 Pass
0.0723 1974 1974 100 Pass
0.0729 1905 1905 100 Pass
0.0736 1864 1864 100 Pass
0.0743 1804 1804 100 Pass
0.0749 1752 1752 100 Pass
0.0756 1707 1707 100 Pass
0.0762 1646 1646 100 Pass
0.0769 1599 1599 100 Pass
0.0776 1555 1555 100 Pass
112219 WWHM 11/22/2019 12:15:50 PM Page 25
Duration Flows
The Facility PASSED
Flow(cfs)Predev Mit Percentage Pass/Fail
0.0776 1555 1555 100 Pass
0.0804 1331 1331 100 Pass
0.0832 1193 1193 100 Pass
0.0860 1051 1051 100 Pass
0.0888 945 945 100 Pass
0.0916 845 845 100 Pass
0.0944 747 747 100 Pass
0.0972 662 662 100 Pass
0.1000 593 593 100 Pass
0.1028 519 519 100 Pass
0.1056 464 464 100 Pass
0.1084 422 422 100 Pass
0.1112 380 380 100 Pass
0.1140 347 347 100 Pass
0.1168 307 307 100 Pass
0.1196 272 272 100 Pass
0.1224 248 248 100 Pass
0.1252 217 217 100 Pass
0.1280 197 197 100 Pass
0.1308 175 175 100 Pass
0.1336 160 160 100 Pass
0.1364 148 148 100 Pass
0.1392 135 135 100 Pass
0.1420 126 126 100 Pass
0.1448 108 108 100 Pass
0.1476 97 97 100 Pass
0.1504 89 89 100 Pass
0.1532 82 82 100 Pass
0.1560 76 76 100 Pass
0.1588 65 65 100 Pass
0.1616 60 60 100 Pass
0.1644 51 51 100 Pass
0.1672 51 51 100 Pass
0.1700 46 46 100 Pass
0.1728 44 44 100 Pass
0.1756 39 39 100 Pass
0.1784 35 35 100 Pass
0.1812 33 33 100 Pass
0.1840 29 29 100 Pass
0.1868 29 29 100 Pass
0.1896 28 28 100 Pass
0.1924 23 23 100 Pass
0.1952 22 22 100 Pass
0.1980 21 21 100 Pass
0.2008 21 21 100 Pass
0.2036 18 18 100 Pass
0.2064 13 13 100 Pass
0.2092 11 11 100 Pass
0.2120 9 9 100 Pass
0.2148 9 9 100 Pass
0.2176 8 8 100 Pass
0.2204 7 7 100 Pass
0.2232 7 7 100 Pass
112219 WWHM 11/22/2019 12:15:50 PM Page 26
0.2260 7 7 100 Pass
0.2288 7 7 100 Pass
0.2316 7 7 100 Pass
0.2344 7 7 100 Pass
0.2372 7 7 100 Pass
0.2400 6 6 100 Pass
0.2428 5 5 100 Pass
0.2456 5 5 100 Pass
0.2484 4 4 100 Pass
0.2512 4 4 100 Pass
0.2540 4 4 100 Pass
0.2569 4 4 100 Pass
0.2597 4 4 100 Pass
0.2625 4 4 100 Pass
0.2653 4 4 100 Pass
0.2681 4 4 100 Pass
0.2709 4 4 100 Pass
0.2737 4 4 100 Pass
0.2765 4 4 100 Pass
0.2793 4 4 100 Pass
0.2821 4 4 100 Pass
0.2849 3 3 100 Pass
0.2877 3 3 100 Pass
0.2905 3 3 100 Pass
0.2933 3 3 100 Pass
0.2961 3 3 100 Pass
0.2989 3 3 100 Pass
0.3017 3 3 100 Pass
0.3045 3 3 100 Pass
0.3073 3 3 100 Pass
0.3101 3 3 100 Pass
0.3129 3 3 100 Pass
0.3157 3 3 100 Pass
0.3185 3 3 100 Pass
0.3213 3 3 100 Pass
0.3241 3 3 100 Pass
0.3269 3 3 100 Pass
0.3297 3 3 100 Pass
0.3325 3 3 100 Pass
0.3353 3 3 100 Pass
0.3381 3 3 100 Pass
0.3409 3 3 100 Pass
0.3437 3 3 100 Pass
0.3465 3 3 100 Pass
0.3493 3 3 100 Pass
0.3521 3 3 100 Pass
0.3549 3 3 100 Pass
112219 WWHM 11/22/2019 12:15:50 PM Page 27
Water Quality
Water Quality BMP Flow and Volume for POC #2
On-line facility volume:0.0519 acre-feet
On-line facility target flow:0.0626 cfs.
Adjusted for 15 min:0.0626 cfs.
Off-line facility target flow:0.0354 cfs.
Adjusted for 15 min:0.0354 cfs.
112219 WWHM 11/22/2019 12:15:50 PM Page 28
LID Report
112219 WWHM 11/22/2019 12:15:50 PM Page 29
Model Default Modifications
Total of 0 changes have been made.
PERLND Changes
No PERLND changes have been made.
IMPLND Changes
No IMPLND changes have been made.
112219 WWHM 11/22/2019 12:15:50 PM Page 30
Appendix
Predeveloped Schematic
112219 WWHM 11/22/2019 12:15:52 PM Page 31
Mitigated Schematic
Appendix 3
Soils Report
Materials Testing & Consulting, Inc.
Geotechnical Engineering ● Materials Testing ● Special Inspection ● Environmental Consulting
Corporate 777 Chrysler Drive Burlington, WA 98233 Phone 360.755.1990 Fax 360.755.1980
SW Region 2118 Black Lake Blvd. S.W. Olympia, WA 98512 Phone 360.534.9777 Fax 360.534.9779
NW Region 805 Dupont, Suite #5 Bellingham, WA 98225 Phone 360.647.6061 Fax 360.647.8111
Kitsap Region 5451 N.W. Newberry Hill Road, Suite 101 Silverdale, WA 98383 Phone/Fax 360.698.6787
Visit our website: www.mtc-inc.net
December 12, 2016
Seth Borman
P.O. BOX 2249
Yelm, Washington 98597
253 209 8550
sethborman@yahoo.com
Subject: Borman Residential Geotechnical Study
Rice Street SW & Washington Street SW (Parcel #75300901200 & 75300901400)
Yelm, Washington
MTC Project No.: 16S136
Dear Mr. Borman:
This letter transmits our Geotechnical Investigation Report for the above-referenced project. Materials
Testing & Consulting, Inc. (MTC) performed this geotechnical study in accordance with our Proposal
for Geotechnical Services, dated August 31, 2016.
We would be pleased to continue our role as your geotechnical engineering consultants during the
project planning and construction. We also have a keen interest in providing materials testing and
special inspection during construction of this project. We will be pleased to meet with you at your
convenience to discuss these services.
We appreciate the opportunity to provide geotechnical services to you for this project. If you have any
questions regarding this report, or if we can provide assistance with other aspects of the project, please
contact me at (360) 534-9777.
Respectfully Submitted,
MATERIALS TESTING & CONSULTING, INC.
Luke McCann, G.I.T. John Gillaspy, L.E.G.
Project Geologist NW Region Geotechnical Manager
Attachment: Geotechnical Investigation Report
ii
BORMAN RESIDENTIAL
GEOTECHNICAL INVESTIGATION
FOURTEEN UNIT HOUSING COMPLEX
RICE STREET SW & WASHINGTON STREET SW
PARCEL #75300901200 & 75300901400
YELM, WASHINGTON
Seth Borman
P.O. BOX 2249
Yelm, Washington 98597
253 209 8550
sethborman@yahoo.com
Prepared by:
___________________________ ___________________________
Luke P. McCann, G.I.T. John R. Gillaspy, L.E.G.
Project Geologist NW Region Geotechnical Division Manager
MATERIALS TESTING & CONSULTING, INC. (MTC)
2118 Black Lake Blvd. SW
Olympia, Washington 98512
Phone: (360) 534-9777
Fax: (360) 534-9779
December 12, 2016
MTC Project Number: 16S136
Copyright 2016 Materials Testing & Consulting, Inc.
All Rights Reserved
12-12-2016
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
iii
Table of Contents
1.0 INTRODUCTION ............................................................................................................... 1
1.1 GENERAL ...................................................................................................................................................... 1
1.2 PROJECT DESCRIPTION ............................................................................................................................. 1
1.3 PURPOSE AND SCOPE OF SERVICES ...................................................................................................... 2
2.0 SITE EXPLORATION AND LABORATORY TESTING ................................................ 3
2.1 SITE EXPLORATION ................................................................................................................................... 3
2.2 LABORATORY TESTING ............................................................................................................................ 3
3.0 EXISTING SITE CONDITIONS ........................................................................................ 4
3.1 SURFACE DESCRIPTION ............................................................................................................................ 4
3.2 AREA GEOLOGY ......................................................................................................................................... 4
3.3 SOIL CONDITIONS ...................................................................................................................................... 5
3.4 GROUNDWATER CONDITIONS ................................................................................................................ 6
4.0 KEY GEOLOGIC CONSIDERATIONS ............................................................................ 7
4.1 GENERAL SITE SOIL CONDITIONS ......................................................................................................... 7
4.2 SCOPE OF SITE GRADING ......................................................................................................................... 7
4.3 TEMPORARY EXCAVATION CUT SLOPES, SHORING, AND DEWATERING ................................... 8
5.0 DESIGN RECOMMENDATIONS ..................................................................................... 9
5.1 FOUNDATION FEASIBILITY ..................................................................................................................... 9
5.2 FOUNDATION RECOMMENDATIONS ..................................................................................................... 9
5.3 SLAB-ON-GRADE CONSTRUCTION ....................................................................................................... 11
5.4 SEISMIC DESIGN PARAMETERS AND LIQUEFACTION POTENTIAL ............................................. 12
5.5 INFILTRATION ANALYSIS & COMMENTARY .................................................................................... 13
6.0 CONSTRUCTION RECOMMENDATIONS ................................................................... 16
6.1 EARTHWORK ............................................................................................................................................. 16
6.1.1 Excavation ........................................................................................................................................... 16
6.1.2 Clearing, Grubbing, and Grading ........................................................................................................ 16
6.1.3 Subgrade Evaluation and Preparation .................................................................................................. 16
6.1.4 Site Preparation, Erosion Control and Wet Weather Construction ...................................................... 17
6.2 STRUCTURAL FILL MATERIALS AND COMPACTION ...................................................................... 18
6.2.1 Materials .............................................................................................................................................. 18
6.2.2 Placement and Compaction ................................................................................................................. 18
6.3 TEMPORARY EXCAVATIONS AND SLOPES ........................................................................................ 19
6.4 PERMANENT SLOPES ............................................................................................................................... 20
6.5 UTILITY TRENCHES AND EXCAVATIONS .......................................................................................... 20
7.0 ADDITIONAL RECOMMENDED SERVICES .............................................................. 21
8.0 LIMITATIONS .................................................................................................................. 22
Appendix A. SITE LOCATION AND VICINITY ...................................................................... 23
Appendix B. SITE PLAN & EXPLORATION LOCATIONS .................................................... 24
Appendix C. EXPLORATION LOGS ....................................................................................... 25
Appendix D. LABORATORY RESULTS .................................................................................. 36
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
1
1.0 INTRODUCTION
1.1 GENERAL
This report presents the findings and recommendations of Materials Testing & Consulting, Inc.’s (MTC)
geotechnical investigation conducted in support of the design and construction of the proposed multi-
unit housing complex and associated site improvements. The proposed project site is located on a
vacant lot directly east of the intersection of Rice Street SW and Washington Street SW in Yelm, Skagit
County, Washington. Maps depicting general building locations (based on client provided sketches) and
aerial photography of existing conditions are provided in Figures 1 and 2 of Appendices A and B.
1.2 PROJECT DESCRIPTION
It is our understanding that the proposed project consists of the development of up to four multi-family
structures (three 4-plex and on duplex) within the site. The site is comprised of Parcels 75300901200
and 75300901400, and is 250 feet long NW-SE by 120 feet wide. The main development area is
roughly 0.5 acres in size, taking up about ¾ of the total lot size. MTC understands from discussion with
the project civil engineer that stormwater facilities are currently anticipated to utilize on-site infiltration,
assuming favorable conditions are present. At this time, the project is undergoing conceptual design and
may be subject to change based on the findings of subsurface investigation, as well as other client
considerations for final design. The purpose of this study has been to provide an overview site
characterization with general geotechnical recommendations for development as well as limited
commentary on specific design aspects such as stormwater design.
Topography of the project site is typically gentle and rolling, with the site being generally elevated 2 to
3 feet above the surrounding road grade. The area of the currently proposed development is vacant,
moderately vegetated land within Yelm proper. The site development is anticipated to require the
removal of trees, vegetation, and local uncontrolled fills within the concentrated development zone.
Based on preliminary project concepts and site information provided to date, construction is assumed to
incorporate some local grading expected for the removal of unsuitable prior fill materials placed on site.
Foundations are likely to consist of shallow continuous perimeter and spread footings with relatively
light loads, and slab-on-grade elements where applicable. It is anticipated that loads will be typical for
the type and materials of construction, and no unusually large or vibratory loads are expected.
MTC should be allowed to review the final plans and specifications for the project to ensure that the
recommendations presented herein are appropriate. Recommendations and conclusions presented by
this report will need to be re-evaluated in the event that changes to the proposed construction are made.
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
2
1.3 PURPOSE AND SCOPE OF SERVICES
The purpose of our study was to explore subsurface conditions at the site and provide geotechnical
recommendations for design and construction of the proposed developments. To evaluate subsurface
soil and water conditions, MTC directed and logged excavator test pits, obtained soil samples, and
utilized Wildcat Dynamic Cone Penetrometer (DCP) for bearing capacity evaluation in the vicinity of
the proposed building locations. At the request of the client, services also included a general assessment
of site soil infiltration potential and determination of rates via gradation methods per applicable
municipal and state guidelines. Our scope of services was consistent with that presented in our Proposal
for Geotechnical Engineering Services, dated August 31, 2016.
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2.0 SITE EXPLORATION AND LABORATORY TESTING
2.1 SITE EXPLORATION
MTC’s site exploration activities were performed on September 8, 2016. Field methods involved the
advancement of Wildcat Dynamic Cone Penetrometer (DCP) tests, and observing the excavation of 4
machine-assisted test pits distributed among the proposed development areas. Test pit locations focused
on new construction areas within the site, with the goal of understanding general subsurface soil and
groundwater characteristics and foundation bearing conditions, as well as to sample soils for laboratory
testing. DCP locations were primarily performed near test pit locations and between pits in order to
confirm subsurface soil density/consistency and correlate with test pit soil observations.
Exploration locations were selected and field-located by an MTC staff geologist while on site to provide
representative coverage as possible of the site areas proposed for development. Test pit excavations
were performed by a client-supplied excavator and operator under observation and direction by MTC
personnel. Test pits were excavated to depths ranging from 12.5 to 13.5 feet below present grade
(BPG), and all pits were terminated at practical machine reach depths within soils exhibiting dense
conditions. Supplemental Wildcat DCP tests were advanced until reaching practical refusal on dense or
hard soils. Three Wildcat DCP tests were started at the existing site surface, and two were started below
existing site grade via potholing for better assessment of soils at intermediate depths.
Locations for explorations were based on pace-and-compass locating, GPS navigation and direct
measurement with standard hand equipment. All test locations are shown approximately on Appendix
B, Figure 2. Additional information on the site exploration program is discussed with our exploration
logs for the test pits and DCP results presented in Appendix C of this report.
2.2 LABORATORY TESTING
Laboratory tests were performed on selected soil samples in accordance with ASTM standards to
determine index and engineering properties of the site soils. Tests included supplementary soil visual
classification of collected samples, grain-size distribution tests (sieve analysis), and natural moisture
content determination. Laboratory test results are presented on the test reports included within
Appendix D.
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3.0 EXISTING SITE CONDITIONS
3.1 SURFACE DESCRIPTION
The project site is located near the geographic center of the City of Yelm, Washington in an existing
developed residential neighborhood southwest of West Yelm Avenue. The site is rectangular in shape
and approximately 0.5 acres, comprised of two parcels, with total dimensions of approximately 120 feet
NE-SW and 250 feet NW-SE. The site is bordered to the northwest by Rice Street SW, and by
Washington Street SW along its southwest perimeter. An existing gravel alley running behind the
property borders the northeast. A separate property containing a single-family residence and yard exists
along the southeastern boundary. Surrounding the property in all directions are small (0.25 acres or less)
residential lots which are predominantly occupied.
Young deciduous and sapling regrowth trees are scattered within the site, with a few more mature fir
trees present. Trees generally stand straight and vertical. Existing understory vegetation cover of tall
grass and brambles are omnipresent. Certain locations within the site are grown thick with undergrowth,
while other sections contain sparse low-lying cover. The property is generally traversable by foot. It is
assumed that the site was used to deposit grading spoils during development of surrounding lots, as
evidenced by the presence of interpreted uncontrolled fill soils over the surface, buried topsoils, and the
varying, apparently artificial surface topography of some areas.
Topography of the project site is typically gentle and rolling, with the site surface being generally
elevated 2 to 3 feet above the surrounding road grade, due to historic fill activities. No other significant
surface improvements are present. There are no major bodies of water or seasonal channels found
within, or adjacent to, the subject area. The ground surface was dry during the site visit in the late
summer season. The elevation of the project area is roughly 355 feet above sea level.
3.2 AREA GEOLOGY
The map of Hydrology and quality of ground water in northern Thurston County, Washington, scale
1:100,000 (Drost et al, 1998) published by the U.S. Geological Survey indicates the project site is
located completely within a wide expanse of Pleistocene-age Vashon Stade Recessional Outwash
deposits (Qvr). The Washington Interactive Geologic Map also depicts the site within an expanse of
(Qgog) Vashon Stade Continental Glacial Outwash Gravel (available from DNR, accessed online). The
unit mantles the surface commonly throughout most of the Yelm area. It is defined as recessional and
proglacial, stratified pebble, cobble, and boulder gravel deposited in meltwater streams and their deltas;
locally containing ice-contact deposits. The unit includes Steilacoom Gravel and part of the Vashon
Drift.
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Shallow soils are mapped by the USDA NRCS Web Soil Survey as (110) Spanaway gravelly sandy
loam, 0 to 3 percent slopes for the approximate northeastern half of the site, and Spanaway stony sandy
loam, 0 to 3 percent slopes for the approximate southwestern half of the site. Both units are described
similarly, forming on outwash plains and terraces, and are derived from volcanic ash over gravelly
outwash. This soil typically consists of gravelly sandy loam becoming increasingly gravelly overtop of
extremely gravelly sand at depths greater than about 20 to 22 inches. The units are somewhat
excessively drained in their upper stratigraphy, assigned to Hydrologic Group A. Water transmission
capacity of the most limiting layer is considered high (1.98 to 5.95 inches per hour). Depth to the
seasonal water table and restrictive features is typically more than 80 inches.
Soil conditions encountered in the field, beneath uncontrolled fills and topsoils, generally consist of
gravel and gravel with sand below typical depths of approximately 2.0 to 4.5 feet BPG. These
conditions appear native and representative of Vashon Stade glacial outwash deposits, and thus are
consistent with local area geology sources.
3.3 SOIL CONDITIONS
A general characterization of on-site soil units encountered during our exploration is presented below.
The exploration logs in Appendix C present details of soils encountered at each exploration location.
The on-site soils are generally summarized as follows in stratigraphic order to depth:
Uncontrolled Fill and Topsoil Cover (OL-SM, GP-GW) – Organic Silt, Gravel Mixtures:
Cover deposits of apparent uncontrolled fill and landscape dressing topsoil were encountered
throughout the site. The client reported that historic fill exists over most of the site in varying
thicknesses. Generally, cover soils consisted of layers or mixtures of organic detritus, topsoils,
and sandy gravels, extending to depths of 2.5 to 3.5 feet maximum. The thickness corresponds
roughly with the difference in surface grade variation of the site interior.
Topsoil material of organic silt to silty sand was observed at the surface at all test pit locations.
Entrained organic material at the surface included duff, ferns, plants, fallen branches, and roots.
The topsoil was dark brown in color, soft or loose and dry to damp. Thickness was typically a
few inches to around 1 foot, but was locally thicker. Test pit TP-1 revealed what appeared to be
a relict native topsoil horizon, below the fill, from approximately 3.5 to 4.5 feet BPG. At TP-4,
no gravelly fill was present but topsoil containing gravel was present to 2.0 feet BPG.
Underlying gravel soils of confirmed or suspected fill origin contained varying sand content,
minor silt, and some intermixed organics and roots. The soil was dry and was locally loose to
dense. No obvious refuse or foreign debris was encountered.
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Glacial Outwash Deposits (SW, GP, GW) – Sand with Gravel to Gravel with Sand:
Soils consisting of varying components of gravel and sand with minor to trace fines content were
encountered at all test pit and DCP locations beneath the cover fills and relict topsoils where
present. Apparent native glacial outwash soils were found at depths as shallow as 2.0 feet BPG
(TP-4) and as deep as 4.5 feet BPG (TP-1), but on average were present by about 3 feet depth.
The upper 2 to 3 feet of the unit appeared lightly altered by weathering, locally exhibiting an
orangish-tan in color and dry at the time of the investigation. Shallow portions commonly
displayed minor bands of sands and gravels, with a medium density increasing to a generally
dense condition with depth. Gravel was typically rounded to sub-rounded, and commonly
ranged from approximately 2 inches to 12 inches in diameter, with some cobbles up to 18 inches
in diameter. Interbedded lenses of smaller gravel, less than 1 inch in diameter, were observed in
some locations. With depth, outwash deposits became more uniform in color and composition.
Soils were light brown in color, and dense becoming very dense below. Exploration tests were
terminated within this unit due to consistently dense conditions persisting to maximum depths
explored.
3.4 GROUNDWATER CONDITIONS
No significant surface water features were observed on the site or in the close vicinity. No standing
water was observed on site in the late-summer season. The nearest feature of surface water to the
project site is Yelm Creek, approximately 2000 feet to the north.
During field explorations, no water seepage was observed within any test pit or DCP location. No water
table was encountered by typical termination depths of 12.0 to 13.5 feet BPG at any test location. Given
the timeframe of the explorations in the mid-summer, conditions appeared typical for the dry season,
when water levels are anticipated to be relatively low. During test pit explorations, no obvious evidence
of seasonal high groundwater conditions, perched water phenomena, or restrictive horizons was
observed. Light oxidation staining observed sporadically is interpreted as resulting from downward
infiltration of surface water and local soil composition.
MTC’s scope of investigation did not include observation and determination of seasonal variations,
conclusive measurement or monitoring of groundwater elevations at the time of exploration, or
determination of regional groundwater levels past the depths explored. Given the topography of the site
area, known geology, and relationship to major surface water features in the vicinity, regional
groundwater levels are anticipated to be below the realm of concern for this study.
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4.0 KEY GEOLOGIC CONSIDERATIONS
This section discusses significant geotechnical aspects that must be addressed in project planning and
design. These considerations form the basis for the geotechnical engineering design recommendations
presented in Section 5.0 and construction recommendations presented in Section 6.0.
4.1 GENERAL SITE SOIL CONDITIONS
The results of MTC’s investigation indicate shallow conditions throughout the site consist primarily of
medium dense to dense uncontrolled gravel fill soils. Apparent fills are capped with silty topsoil and
existing brushy vegetation, and locally underlain by organic-rich soils interpreted as relict topsoil (TP-
1). At one location, gravel fills were absent but topsoil cover was relatively thick (TP-4). The suspected
fill origin of surface soils was noted by the client as well as suggested by topographic conditions within
the site, and may correspond to prior development of the surrounding properties. Depth to a suitable
native soil bearing stratum ranged from 2.0 to 4.5 feet BPG maximum, averaging around 3 feet in the
middle of the site while deepest at the northwest end and generally shallowing to the southeast.
Underlying native glacial outwash soils consisting of medium dense to very dense gravels and sands
were encountered at all locations to maximum depths explored. In-situ density generally increases with
depth. On-site infiltration also appears viable within native soils, with no groundwater or obvious
restrictive conditions encountered by end depths of 12.0 to 13.5 feet BPG and high permeability soils
available at likely facility depths.
Foundation design specifications were not available to MTC at the time of this report. The assumptions
in this report are based on consultation with the client regarding anticipated building design and site
preparations. MTC assumes that the buildings will employ a typical shallow foundation of continuous
perimeter footings and spread footings, as well as slab-on-grade floor elements. Finished grade is
assumed to be similar to the road grade surrounding the site after stripping of roughly 3 feet of
overburden fills from the site interior. Soils at likely foundation subgrade level typically consist of
medium dense to dense native sand and gravel appearing suitable as bearing soils.
4.2 SCOPE OF SITE GRADING
A detailed grading plan was not available to MTC at the time of this report. Based on discussions with
the client and provided conceptual plans as well as observation of existing topography, this study
assumes finished site grade will approximate existing road grade surrounding the site following the
removal of the uncontrolled fill within structural and surface pavement locations on site. Referenced
depths refer to existing grade unless noted otherwise. The recommendations below incorporate and
assume regrading and removal of uncontrolled fill from beneath structures and pavement sections.
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4.3 TEMPORARY EXCAVATION CUT SLOPES, SHORING, AND DEWATERING
Plans for excavation including temporary cut slopes and proposed shoring methods were not available to
MTC at the time of report production. Most excavations are anticipated to be shallow. However, with
excavations for foundations and utility improvements that may exceed 4 feet depth, it is possible that
one or both techniques will be used. Section 6.3 below provides general recommendations for treatment
of temporary excavations. MTC can provide further consultation, design, and evaluation services for cut
slopes if desired prior to and during construction. If shoring is required beyond typical OSHA
standards, MTC can provide geotechnical engineering services for shoring design upon request.
Some amount of dewatering may be necessary for deep confined excavations if work occurs in the
winter season. No groundwater was observed during our site investigation that was completed during
the dry summer months. General recommendations for site preparation and wet weather construction
are addressed in section 6.1.3 below. However, it should be noted that this study did not include a
hydrogeologic evaluation necessary for accurate appraisal of site flow conditions or volume estimates
and is only generally suitable for planning and design of dewatering methods.
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5.0 DESIGN RECOMMENDATIONS
5.1 FOUNDATION FEASIBILITY
Two requirements must be fulfilled in design of foundations: first, loads must be less than the ultimate
bearing capacity of foundation soils to maintain stability and, second, differential settlement must not
exceed an amount that will produce adverse behavior of the structure. Allowable settlement is typically
exceeded before bearing capacity considerations become important; thus, the allowable bearing pressure
is normally controlled by settlement considerations including differential settlement. Excess settlement
due to adverse soil conditions may be a result of shallow or deep soils, or a combination of both.
Considering the medium dense to dense glacial outwash deposits encountered and absence of shallow
groundwater, as well as the scale of proposed improvements, the site does not appear susceptible to
adverse amounts of deep settlement after the removal of uncontrolled fill and building development.
Therefore, MTC has not recommended any further scope of exploration work and analysis towards deep
settlement potential at this time.
Existing shallow conditions within the site consist of topsoils and prior uncontrolled fills ranging in
observed thickness from 2.0 to 4.5 feet, underlain by glacial outwash sand and gravel deposits. Native
glacial soils to depth appear suitable for direct bearing support of shallow foundation elements, utilizing
the design criteria cited in Section 5.2 below. We recommend avoiding placing foundation elements
within or over existing cover fills and relict topsoils (as thick as 4.5 feet, depths referenced from current
overburden surface grade), due to the inherent potential for variability of the fills, entrained organic
contents, and local buried organic soils such as relict topsoil horizons.
It is the opinion of MTC that a shallow foundation consisting of perimeter continuous footings and
spread footings with a slab-on-grade floor is suitable for use assuming the recommendations provided
below are followed for foundation design, site preparations, and construction methods. MTC
recommends that we be contacted to review plans relating to foundation design and site preparations, to
ensure they are consistent with the content and intent of recommendations provided herein.
5.2 FOUNDATION RECOMMENDATIONS
MTC recommends foundations be placed directly on suitably medium dense to dense native soils, or on
new imported structural fill installed over suitable native soils. Following excavation to proposed
subgrade level, native sand and gravel soils should be recompacted to a suitably dense condition before
constructing footing forms. Assuming site preparation is completed as described herein, we recommend
the following for design and construction of foundations:
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Allowable Soil Bearing Capacity:
2,000 pounds per square foot (psf) for footings placed on native sand and gravel outwash soils of
medium dense consistency, or on compacted structural fill placed locally over these soils per the
recommendations presented herein for Structural Fill Materials and Compaction.
2,500 pounds per square foot (psf) for footings placed on a minimum 18-inch section of
compacted imported structural fill installed over suitably dense and compacted native soils.
The allowable bearing capacity may be increased by 1/3 for transient loading due to wind and
seismic events.
Note: Structural fill placed beneath foundations (such as to raise/level grade or replace
unsuitable soils) should extend a minimum distance past each edge of the footing equal to the
depth of structural fill placed below the footing. For example, for a 2-foot wide perimeter
footing, fill placed to 1.0 feet below footing grade will require a total fill width of 4.0 feet (1 feet
each side plus 2 foot width of footing).
Minimum Footing Depth:
For a shallow perimeter and spread footing system, all exterior footings shall be embedded a
minimum of 18 inches and all interior footings shall be embedded a minimum of 12 inches
below the lowest adjacent finished grade, but not less than the depth required by design.
However, all footings must penetrate to the prescribed bearing stratum cited above, and no
footings should be founded in or above organic or loose soils or uncontrolled fills.
Minimum Footing Width:
Footings should be proportioned to meet stated bearing capacity and/or IBC current minimum
requirements. For a shallow foundation system, continuous strip footings should be at minimum
16 inches wide and interior or isolated column footings at minimum 24 inches wide.
Estimated Settlements:
We estimate that the maximum settlements will be approximately 1 inch, or less, with a
differential settlement of ½ inch, or less, over 50 linear feet. Settlement is anticipated to occur
when the load is applied during construction.
Lateral Load Resistance:
Lateral loads can be resisted by passive pressure against buried portions of the foundation
elements and sliding resistance along its base. We recommend an allowable lateral pressure
equal to that generated by a fluid with an equivalent fluid weight of 200 pcf EFW. This value
assumes footings are backfilled with imported structural fill, or placed directly against intact
native dense soils, and includes a factor of safety of two. The upper 18 inches of soil should be
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ignored unless the area is paved or covered with concrete, due to soil softening associated with
freeze/thaw.
Sliding resistance between native coarse-grained subgrade or imported structural fill and the
foundation base should be evaluated using an allowable coefficient of friction of 0.35. This
value assumes concrete placed directly on the subgrade and includes a factor of safety of 1.5.
5.3 SLAB-ON-GRADE CONSTRUCTION
A slab-on-grade floor is assumed to be incorporated for portions of building interiors. No details on slab
loading conditions were provided at the time of this study. We assume interior floors are anticipated to
be subject to light live loading from foot traffic and relatively light dead loads. MTC recommends the
following activities and parameters for slab-on-grade design and construction intended to provide
reinforcement against shallow soil variations and potential adverse effects of differential settlement. For
the purpose of this report, we assume finished slab grade will be similar to or marginally above present
street grade after stripping of uncontrolled fills and final site grading.
Slab Subgrade Preparations:
All unsuitably soft, organic, or shallow yielding soils and uncontrolled fills should be removed
from beneath floor slab areas. Native glacial soils of medium dense to dense quality appear
suitable for subgrade below slab-on-grade interiors and exterior flatworks, assuming soils are
verified as firm and unyielding during construction. Local areas of excessively loose native
subgrade or deeper uncontrolled fills, if encountered, will require additional overexcavation and
replacement with structural fill during slab preparations. Upon excavation to planned subgrade
elevation, we recommend native sand and gravel subgrade be recompacted using a vibratory
drum roller of sufficient size.
If final slab grade is planned to be higher than surrounding grade, we recommend following the
above-prescribed preparations before constructing a structural fill pad.
Subgrade Modulus:
A Subgrade Modulus (k) of 150 pci is recommended for use in design of slab-on-grade floors
constructed over a compacted native subgrade or structural fill pad. This is assuming the slab
will be placed on an angular rock capillary break, if utilized, installed and compacted over
suitably dense subgrade.
Proof Roll:
Prior to placement of capillary break material and slab construction, the proposed slab subgrade
or structural fill pad shall be proof-rolled to confirm no soft or deflecting areas are present. This
is to ensure the existing base is evenly prepared and adequate for support of the slab. MTC
recommends that we be contacted for observation of the proof roll and final visual confirmation
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of prepared base suitability. Areas of excessive rutting, pumping, or yielding shall be excavated
and backfilled with new structural fill as described herein.
Capillary Break:
A capillary break will be helpful to ensure a dry slab floor and reduce the potential for floor
damage resulting from moisture issues. If elected for use, to provide a capillary moisture break,
a 6-inch thick, properly compacted granular mat consisting of open-graded, free-draining angular
aggregate is recommended below floor slabs. To provide additional slab structural support, and
to substitute for a portion of a structural fill base pad where specified, MTC recommends the
capillary break consist of crushed rock all passing the 1-inch sieve and no more than 3 percent
(by weight) passing the U.S. No. #4 sieve, compacted in accordance with Section 6.2.2 below.
Vapor Barrier:
A vapor retarding membrane such as 10-mil polyethylene film should be placed beneath all floor
slabs to prevent transmission of moisture through the slabs where floor coverings may be
affected. Care should be taken during construction not to puncture or damage the vapor
retarding membrane. To protect the membrane, a layer of sand no more than 2 inches thick may
be placed over the membrane if desired.
Loaded Slabs and Structural Design Considerations:
For slabs proposed for loading due to heavier storage or interior vehicle parking/access, we
recommend these slabs be designed for increased rigidity and self-support in order to help
counteract the increased risk for differential settlement under higher loading conditions. MTC
suggests at least a minimum unreinforced concrete structural section of 6.0 inches be employed,
or as specified by the project engineer. It is generally recommended that these slabs be designed
to incorporate reinforcing to help span variable soils and eliminate potential cracking. In
addition, trafficked slabs may call for minimum structural fill sections to be placed to support
traffic loads per the designer.
We assume design and specifications of slabs and consideration of their loading requirements
will be assessed by the project structural engineer. MTC recommends that we be contacted to
review specifications for heavily loaded or traffic areas if present, and to provide additional
recommendations appropriate to the type and magnitude of loading in conjunction with the
location and proposed elevation versus existing grade.
5.4 SEISMIC DESIGN PARAMETERS AND LIQUEFACTION POTENTIAL
According to the Liquefaction Susceptibility Map of Thurston County, Washington (accessed online via
DNR Interactive Map), the site area is identified as having a very low liquefaction susceptibility. The
accompanying Seismic Site Class Map classifies the general project area as Site Class C, representing a
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moderate potential for increased amplitude of ground shaking during a seismic event corresponding to
very dense soils. Liquefaction is a phenomenon associated with a subsurface profile of relatively loose,
noncohesive soils saturated by groundwater. Under seismic shaking the pore pressure can exceed the
soil’s shear resistance and the soil ‘liquefies’, which may result in excessive settlements that are
damaging to structures and disruptive to exterior improvements. Based on the results of site
explorations, MTC interprets the site to have a low risk of liquefaction due to the prevalence of medium
dense to dense glacial outwash deposits and absence of shallow groundwater.
The USGS Seismic Design Map Tool was used to determine site-specific seismic design coefficients and
spectral response accelerations for the project site assuming design Site Class D, representing a
subsurface profile (upper 100 feet) of generally dense soil conditions as encountered in field
explorations. Parameters in Table 1 were calculated using 2008 USGS hazard data and 2012/2015
International Building Code standards:
Table 1. Seismic Design Parameters – Site Class D
Mapped Acceleration Parameters (MCE horizontal) SS 1.249 g
S1 0.498 g
Site Coefficient Values Fa 1.000
Fv 1.502
Calculated Peak SRA SMS 1.250 g
SM1 0.748 g
Design Peak SRA (2/3 of peak) SDS 0.833 g
SD1 0.499 g
Seismic Design Category – Short Period (0.2 Second) Acceleration D
Seismic Design Category – 1-Second Period Acceleration D
5.5 INFILTRATION ANALYSIS & COMMENTARY
Gradation Analysis Method & Results
During test pit excavations for general site investigation, MTC collected representative samples of
native soil deposits among potential infiltration strata and depths. Per initial project discussions,
potential target depths were assumed to range from a minimum of 3 feet to a maximum of 10 feet BPG
(as referenced from existing overburden surface), with refinement of the design depths and locations to
follow the results of this study. We understand the project will be subject to infiltration design based on
the Washington Department of Ecology Stormwater Management Manual for Western Washington
(DoE SMMWW), 2012 edition, as accepted by the city of Yelm. For initial site infiltration
characterization within the scope of this study, laboratory gradation analyses were completed including
sieve tests for stormwater design characterization and rate determination to supplement field
observations. Results of laboratory testing in terms of rate calculation are summarized below.
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Laboratory results were interpreted to recommended design inputs in accordance with methods of the
2012 DoE SMMWW. Gradation results were applied to the Massmann (2003) equation (1) to calculate
Ksat representing the initial saturated hydraulic conductivity.
(1) log10(Ksat) = -1.57 + 1.90*D10 + 0.015*D60 - 0.013*D90 - 2.08*ff
Table 2 reports for each sample the input laboratory values and calculated Ksat. Corrected Ksat values
presented below are a product of the initial Ksat and correction factor CFT. For a generalized site-wide
design situation, we have applied a conservative site variability factor of CFv = 0.4 along with typical
values of CFt = 0.4 (for the Grain Size Method) and CFm = 0.9 (assuming standard influent control).
(2) CFT = CFv x CFt x CFm = 0.4 x 0.4 x 0.9 = 0.14
Table 2. Results of Massmann Analysis
TP # Depth
(BPG) USCS D10 D60 D90 Ff (%) Ksat
(inches/hour)
Corrected Ksat
(inches/hour)
3 3 GP 0.803 28.499 40.746 0.6 785.85 110.0
3 6 GW 0.365 33.039 44.439 1.6 144.40 20.2
1 10 GW 0.295 30.768 51.003 3.3 74.44 10.4
Facility Design Discussion and Recommended Rate
MTC understands the stormwater management system is undergoing design at this time, and pending the
results of this assessment to confirm general site feasibility. Infiltration facilities are presently
anticipated to be placed within the proposed parking area, in the vicinity of test pit TP-3. No restrictive
horizons or evidence of seasonal high groundwater conditions were encountered in our excavation in
this location or elsewhere on site to exploration depths of 12.0 to 13.5 feet BPG. The infiltration system
will need to be placed at sufficient depth to bypass the overburden of organic soils and uncontrolled fills,
and infiltrate directly into the highly permeable coarse-grained native soils.
Grain Size analysis methods yielded Corrected Ksat values ranging from 10.4 to 110.0 inches/hour
corresponding to native soils sampled between 3.0 and 10.0 feet BPG. We recommend discounting the
outlying analysis results from the soil sample from TP-3 at 3 feet BPG, where this excessively high Ksat
value is attributed to a local variation and may not represent a reasonable estimate of site-wide
conditions. Results from the other locations and depths are broadly correlative. The difference in
results yielded from samples at 6.0 and 10.0 feet BPG indicate a variability in infiltration capacity of the
native soils based primarily on fines content, which is consistent with our field observations of locally
varying texture and content. Where such natural variability is encountered, it is typical to recommend
for use the lower-bound end of the range for a conservative approach to infiltration design. Thus, for a
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bulk design application of infiltration facilities in the vicinity of the proposed improvements with final
location and depth to be determined, we recommend using a conservative corrected Ksat maximum
value of 10.0 inches/hour.
MTC recommends the facility designer review these results and stated assumptions per reference
literature to ensure applicability with the proposed development, level of anticipated controls, and long
term maintenance plan. The designer may make reasonable adjustments to correction factors and the
resulting design values based on these criteria to ensure design and operational intent is met. We
recommend that we be contacted if substantial changes to rate determination are considered.
The site may be eligible for a higher design rate based on more rigorous testing at the final design
location and depth. The client can elect to conduct Pilot Infiltration Test (PIT) methods at the actual
infiltration facility location for final design confirmation. The results of in-situ PIT testing are typically
considered more reliable than gradation methods, and thus a lesser degree of conservatism can be
applied to the yielded rates for design application. In our experience, gravelly soils will commonly yield
a higher rate via PIT methods than from gradation analysis.
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6.0 CONSTRUCTION RECOMMENDATIONS
6.1 EARTHWORK
6.1.1 Excavation
Excavations can generally be performed with conventional earthmoving equipment such as bulldozers,
scrapers, and excavators.
Where possible, excavations made within about one foot of finished subgrade level should be performed
with smooth edged buckets to minimize subgrade disturbance and the potential for softening to the
greatest extent practical.
6.1.2 Clearing, Grubbing, and Grading
All topsoils and uncontrolled fills within the proposed building, paving, and infiltration areas will need
to be stripped prior to the placement of structural and stormwater control elements. In addition, any area
accepting structural fill will require stripping before new fill placement. Stripping depths will be
variable due to the differing depths to suitable native soils encountered in explorations. It should be
expected that minimum stripping depths will exceed 24 inches to remove organic-rich soils and
uncontrolled fill materials present throughout the site. See Table 3 below for approximate depths by
location required to reach native non-organic soils. Some areas, especially those containing thick
existing uncontrolled fill, will require additional excavation to uncover suitable native soils. The final
exposed subgrade shall be inspected by a representative of the geotechnical engineer to verify that all
deleterious materials and unsuitable fills have been removed.
Table 3. Approximate Depths to Suitable Bearing Subgrade
Location Minimum Depth to
Bearing Soils (feet)
TP-1 4.5
TP-2 3.5
TP-3 2.5
TP-4 2.0
6.1.3 Subgrade Evaluation and Preparation
After excavations have been completed to the planned subgrade elevations, but before placing fill or
structural elements, the exposed subgrade soils should be evaluated under the full-time observation and
guidance of an MTC representative. Where appropriate, the subgrade should be proof-rolled with a
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
17
minimum of two passes with a fully loaded dump truck, water truck or scraper. In circumstances where
this seems unfeasible, an MTC representative may use alternative methods for subgrade evaluation.
Any loose soil should be compacted to a firm and unyielding condition and at least to 95 percent of the
modified Proctor maximum dry density per ASTM D1557. Any areas that are identified as being soft or
yielding during subgrade evaluation should be over-excavated to a firm and unyielding condition or to
the depth determined by the geotechnical engineer. Where over-excavation is performed below a
structure, the over-excavation area should extend beyond the outside of the footing a distance equal to
the depth of the over-excavation below the footing. The over-excavated areas should be backfilled with
properly compacted structural fill.
6.1.4 Site Preparation, Erosion Control and Wet Weather Construction
During wet weather, the contractor should take measures to protect the exposed subgrades and limit
construction traffic during earthwork activities.
Once the geotechnical engineer or their representative has approved a subgrade, further measures should
be implemented to prevent degradation or disturbance of the subgrade. These measures could include,
but are not limited to, placing a layer of crushed rock or lean concrete on the exposed subgrade, or
covering the exposed subgrade with a plastic tarp and keeping construction traffic off the subgrade.
Once subgrade has been approved, any disturbance because the subgrade was not protected should be
repaired by the contractor at no cost to the owner.
During wet weather, earthen berms or other methods should be used to prevent runoff from draining into
excavations. All runoff should be collected and disposed of properly. Measures may also be required to
reduce the moisture content of on-site soils in the event of wet weather. These measures can include,
but are not limited to, air-drying and soil amendment, etc.
Since soils may be difficult to work with during periods of wet weather due to elevated soil moisture
content, and frozen soil is not suitable for use as structural fill, we recommend that major site
preparation earthwork activities generally take place in late spring, summer or early fall.
Dewatering efforts may be required for confined excavations depending on total excavation depth,
season of construction, and weather conditions during earthwork. MTC recommends major earthwork
activities take place during the dry season if possible to minimize the potential for storm water
inundation of excavations.
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
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6.2 STRUCTURAL FILL MATERIALS AND COMPACTION
6.2.1 Materials
All material placed below structures or pavement areas should be considered structural fill. Structural
fill material shall be free of deleterious material, have a maximum particle size of 4 inches, and be
compactable to the required compaction level.
Overburden topsoils and uncontrolled fills containing notable organic content are not considered suitable
for re-use as structural fill beneath buildings and pavement areas. Predominantly coarse-grained, non-
organic existing fills and native soils consisting of sand-gravel mixtures may be suitable for reuse as
structural fill or as site grade fill outside of structural footprints, subject to approval during construction
by the geotechnical firm and design engineer. Any soil proposed for reuse should be carefully
segregated and stockpiled, and covered from weather in the winter season. During warm, dry weather, it
will likely be necessary to add water to fill soils after residing in stockpiles if stored on site. Material
properties including gradation and moisture content shall be verified to meet project specifications for
the intended use prior to installation.
Imported material can be used as structural fill. Imported structural fill material should conform to
Section 9-03.14(1), Gravel Borrow, of the most recent edition (at the time of construction) of the State
of Washington Department of Transportation Standard Specifications for Road, Bridge, and Municipal
Construction (WSDOT Standard Specifications).
Controlled-density fill (CDF) or lean mix concrete can be used as an alternative to structural fill
materials, except in areas where free-draining materials are required or specified.
Frozen soil is not suitable for use as structural fill. Fill material may not be placed on frozen soil.
The contractor should submit samples of each of the required earthwork materials to the geotechnical
engineer for evaluation and approval prior to delivery to the site. The samples should be submitted at
least 5 days prior to their delivery and sufficiently in advance of the work to allow the contractor to
identify alternative sources if the material proves unsatisfactory.
6.2.2 Placement and Compaction
Prior to placement and compaction, structural fill should be moisture conditioned to within 3 percent of
its optimum moisture content. Loose lifts of structural fill shall not exceed 8 inches in thickness; thinner
lifts will be required for walk-behind or hand operated equipment.
All structural fill shall be compacted to a dense and unyielding condition and to a minimum percent
compaction based on its modified Proctor maximum dry density as determined per ASTM D1557.
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
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Structural fill placed beneath each of the following shall be compacted to the indicated percent
compaction:
Foundation and Floor Slab Subgrades: 95 Percent
Pavement Subgrades (upper 2 feet): 95 Percent
Pavement Subgrades (below 2 feet): 90 Percent
Utility Trenches (upper 4 feet): 95 Percent
Utility Trenches (below 4 feet): 90 Percent
We recommend that fill placed on slopes steeper than 3:1 (H:V) be ‘benched’ in accordance with
hillside terraces entry of section 2-03.3(14) of the WSDOT Standard Specifications.
We recommend structural fill placement and compaction be observed on a full-time basis by an MTC
representative. A sufficient number of tests shall be performed to verify compaction of each lift. The
number of tests required will vary depending on the fill material, its moisture condition and the
equipment being used. Initially, more frequent testing will be required while the contractor establishes
the means and methods required to achieve proper compaction.
6.3 TEMPORARY EXCAVATIONS AND SLOPES
All excavations and slopes must comply with applicable local, state, and federal safety regulations.
Construction site safety is the sole responsibility of the Contractor, who shall also be solely responsible
for the means, methods, and sequencing of construction operations. We are providing soil type
information solely as a service to our client for planning purposes. Under no circumstances should the
information be interpreted to mean that MTC is assuming responsibility for construction site safety or
the Contractor’s activities. Such responsibility is not being implied or inferred.
Temporary excavations in the non-cohesive outwash soils should be inclined no steeper than 2H:1V,
unless approved by the geotechnical engineer based on observation of actual encountered conditions at
the time of construction. Applying lesser grades may also be necessary depending on actual conditions
encountered and the potential presence of water seepage. Heavy construction equipment, building
materials, excavated soil, and vehicular traffic should not be allowed near the top of any excavation.
Where stability of adjoining walls or other structures is endangered by excavation operations, support
systems such as shoring, bracing, or underpinning may be required to provide structural stability and to
protect personnel working within the excavation. Earth retention, bracing, or underpinning required for
the project (if any) should be designed by a professional engineer registered in the State of Washington.
Temporary excavations and slopes should be protected from weather by covering with plastic sheeting
or similar impermeable material. Sheeting sections should overlap at least 12 inches and be tightly
secured with sandbags, staking, or other means to prevent wind from exposing soils under the sheeting.
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
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6.4 PERMANENT SLOPES
MTC recommends that new areas of permanent slopes including fill embankments be inclined no greater
than 3H:1V. Permanent slopes should be planted with a deep-rooted, rapid-growth vegetative cover as
soon as possible after completion of slope construction. Alternatively, the slope should be covered with
plastic, straw, etc. until it can be landscaped.
6.5 UTILITY TRENCHES AND EXCAVATIONS
The contractor shall be responsible for safety of personnel working in utility trenches. Given that steep
excavations in native soils may be prone to caving, we recommend all utility trenches, but particularly
those greater than 4 feet in depth, be supported in accordance with state and federal safety regulations.
Pipe bedding material should conform to the manufacturer’s recommendations and be worked around
the pipe to provide uniform support. Cobbles or boulders exposed in the bottom of utility excavations
should be covered with pipe bedding or removed to avoid inducing concentrated stresses on the pipe.
Trench backfill should be placed and compacted as structural fill as recommended in Section 6.2.
Particular care should be taken to insure bedding or fill material is properly compacted to provide
adequate support to the pipe. Jetting or flooding is not a substitute for mechanical compaction and
should not be allowed.
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
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7.0 ADDITIONAL RECOMMENDED SERVICES
The recommendations made in this report are based on the assumption that an adequate program of tests
and observations will be made during construction to verify compliance with these recommendations.
Testing and observations performed during construction should include, but not necessarily be limited
to, the following:
Observations and testing during site preparation, earthwork, structural fill, and pavement section
placement,
Consultation on temporary excavation cutslopes and shoring if needed,
Testing and inspection of any concrete or masonry included in the final construction plans, and
Geotechnical consultation as may be required prior to and during construction.
We strongly recommend that MTC be retained for the construction of this project to provide these and
other services. Our knowledge of the project site and the design recommendations contained herein will
be of benefit in the event that difficulties arise and either modifications or additional geotechnical
engineering recommendations are required or desired. We can also, in a timely fashion observe the
actual soil conditions encountered during construction, evaluate the applicability of the
recommendations presented in this report to the soil conditions encountered, and recommend
appropriate changes in design or construction procedures if conditions differ from those described
herein.
We further recommend that project plans and specifications be reviewed by us to verify compatibility
with our conclusions and recommendations.
Also, MTC retains fully accredited, WABO-certified laboratory and inspection personnel, and is
available for this project’s testing, observation and inspection needs. Information concerning the scope
and cost for these services can be obtained from our office.
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
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8.0 LIMITATIONS
Recommendations contained in this report are based on our understanding of the proposed development
and construction activities, our field observations and exploration and our laboratory test results. It is
possible that soil and groundwater conditions could vary and differ between or beyond the points
explored. If soil or groundwater conditions are encountered during construction that vary or differ from
those described herein, we should be notified immediately in order that a review may be made and
supplemental recommendations provided. If the scope of the proposed construction, including the
proposed loads or structural locations, changes from that described in this report, our recommendations
should also be reviewed.
We have prepared this report in substantial accordance with the generally accepted geotechnical
engineering practice as it exists in the site area at the time of our study. No warranty, express or
implied, is made. The recommendations provided in this report are based on the assumption that an
adequate program of tests and observations will be conducted by MTC during the construction phase in
order to evaluate compliance with our recommendations. Other standards or documents referenced in
any given standard cited in this report, or otherwise relied upon by the author of this report, are only
mentioned in the given standard; they are not incorporated into it or “included by referenced”, as that
latter term is used relative to contracts or other matters of law.
This report may be used only by Seth Borman and his design consultants and only for the purposes
stated within a reasonable time from its issuance, but in no event later than 18 months from the date of
the report. Note that if another firm assumes Geotechnical Engineer of Record responsibilities they need
to review this report and either concur with the findings, conclusions, and recommendations or provide
alternate findings, conclusions and recommendation under the guidance of a professional engineer
registered in the State of Washington. The recommendations of this report are based on the assumption
that the Geotechnical Engineer of Record has reviewed and agrees with the findings, conclusion and
recommendations of this report.
Land or facility use, on- and off-site conditions, regulations, or other factors may change over time, and
additional work may be required with the passage of time. Based on the intended use of the report,
MTC may recommend that additional work be performed and that an updated report be issued. Non-
compliance with any of these requirements by Mr. Borman or anyone else will release MTC from any
liability resulting from the use of this report by any unauthorized party and Mr. Borman agrees to
defend, indemnify, and hold harmless MTC from any claim or liability associated with such
unauthorized use or non-compliance. We recommend that MTC be given the opportunity to review the
final project plans and specifications to evaluate if our recommendations have been properly interpreted.
We assume no responsibility for misinterpretation of our recommendations.
The scope of work for this subsurface exploration and geotechnical report did not include environmental
assessments or evaluations regarding the presence or absence of wetlands or hazardous substances in the
soil, surface water, or groundwater at this site.
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
23
Appendix A. SITE LOCATION AND VICINITY
Materials Testing & Consulting, Inc.
2118 Black Lake Blvd. SW
Olympia, WA 98512
Regional & Site Vicinity
Proposed Borman Residential
Rice St SW & Washington St SW
Yelm, Washington
FIGURE
1
Source: Google Images, 2016
Site Vicinity
Site Location
Borman Residential Geotechnical Investigation Materials Testing & Consulting December 9, 2016 Project No.: 16S136 24 Appendix B. SITE PLAN & EXPLORATION LOCATIONS Source: Google Images, 2016 * NOT INTENDED FOR CONSTRUCTION USE * NOT TO SCALE – Shown is Approximate Materials Testing & Consulting, Inc. 2118 Black Lake Blvd. SW Olympia, WA 98512 Aerial Photo with Test Locations Proposed Borman Residential Rice St SW & Washington St SW Yelm, Washington FIGURE 2 50 0 SCALE (FEET) 1 inch ~ 50 feet DCP-3 TP-1DCP-1DCP-2TP-3TP-4 DCP-5DCP-4TP-2Approximate Building Locations (Typical)
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
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Appendix C. EXPLORATION LOGS
Grab soil samples were collected from each exploration location by our field geologist during borehole
advancement and test pit excavation. Soil samples collected during the field exploration were classified
in accordance with ASTM D2487. All samples were placed in plastic bags to limit moisture loss,
labeled, and returned to our laboratory for further examination and testing.
Exploration logs from test pits are shown in full in this Appendix. The explorations were monitored by
our field technician who examined and classified the materials encountered in accordance with the
Unified Soil Classification System (USCS), obtained representative soil samples, and recorded pertinent
information including soil sample depths, stratigraphy, soil engineering characteristics, and groundwater
occurrence. Upon completion, test pits were backfilled with native soil tailings.
The stratification lines shown on the individual logs represent the approximate boundaries between soil
types; actual transitions may be either more gradual or more severe. The conditions depicted are for the
date and location indicated only, and it should not necessarily be expected that they are representative of
conditions at other locations and times.
Penetrometer results from Wildcat DCP testing are also shown below. During wildcat penetrometer
advancement, blow counts were recorded in 10 centimeter increments as a thirty-five-pound weight was
dropped a distance of 15 inches. Blow counts were then converted to resistance (kg/cm2), standard
penetration blow counts (N-values), and corresponding soil consistency, as displayed on the logs.
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
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Major Divisions Graph USCS Typical Description
Coarse
Grained Soils
More Than 50%
Retained On
No. 200 Sieve
Gravel
More Than
50% of
Coarse Frac-
tion Retained
On No. 4
Sieve
Clean Gravels
GW Well-graded Gravels, Gravel-Sand Mix-
tures
GP Poorly-Graded Gravels, Gravel-Sand
Mixtures
Gravels With Fines
GM Silty Gravels, Gravel-Sand-Silt Mixtures
GC Clayey Gravels, Gravel-Sand-Clay Mix-
tures
Sand
More Than
50% of
Coarse Frac-
tion Passing
No. 4 Sieve
Clean Sands
SW Well-graded Sands, Gravelly Sands
SP Poorly-Graded Sands, Gravelly Sands
Sands With Fines
SM Silty Sands, Sand-Silt Mixtures
SC Clayey Sands, Clay Mixtures
Fine Grained
Soils
More Than 50%
Passing The
No. 200 Sieve
Silts & Clays Liquid Limit Less
Than 50
ML Inorganic Silts, rock Flour, Clayey Silts
With Low Plasticity
CL Inorganic Clays of Low To Medium
Plasticity
OL Organic Silts and Organic Silty Clays of
Low Plasticity
Silts & Clays
MH Inorganic Silts of Moderate Plasticity
CH Inorganic Clays of High Plasticity
OH Organic Clays And Silts of Medium to
High Plasticity
Highly Organic Soils PT Peat, Humus, Soils with Predominantly
Organic Content
Liquid Limit
Greater Than 50
Unified Soil Classification System Chart
Stratigraphic Contact
Distinct Stratigraphic Contact
Between Soil Strata
Gradual Change Between Soil
Strata
Approximate location of
stratagraphic change
Modifiers
Description
Trace
Some
%
>5
5-12
With >12
DESCRIPTION SIEVE
SIZE
GRAIN SIZE APPROXIMATE SIZE
Boulders > 12” > 12” Larger than a basketball
Cobbles 3 - 12” 3 - 12” Fist to basketball
Gravel
Coarse 3/4 - 3” 3/4 - 3” Thumb to fist
Fine #4 - 3/4” 0.19 - 0.75” Pea to thumb
Coarse #10 - #4 0.079 - 0.19” Rock salt to pea
Medium #40 - #10 0.017 - 0.079” Sugar to rock salt
Fine #200 - #40 0.0029 - 0.017” Flour to Sugar
Fines Passing
#200 < 0.0029” Flour and smaller
Sand
Grain Size
Granular Soils Fine-grained Soils
Density SPT
Blowcount
Consistency SPT
Blowcount
Very Loose 0-4 Very Soft 0-2
Loose 4-10 Soft 2-4
Medium
Dense
10-30 Firm 4-8
Dense 30-50 Stiff 8-15
Very Dense > 50 Very Stiff 15-30
Hard > 30
Soil Consistency
Groundwater observed at time of
exploration
Measured groundwater level in
exploration, well, or piezometer
Perched water observed at time
of exploration
California (3.0” O.D.)
Standard Penetration Test (SPT)
Shelby Tube
Grab or Bulk
Modified California (2.5” O.D.)
Sampler Symbol Description
Materials Testing & Consulting, Inc.
2118 Black Lake Blvd. SW
Olympia, WA 98512
Exploration Log Key
Proposed Borman Residential
Rice St SW & Washington St SW
Yelm, Washington
FIGURE
3
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
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11-09-2016 C:\Documents and Settings\Luke McCann\Desktop\GeoGraphics logs\Borman - TP-1 - CL, LM rev.borMaterials Testing & Consulting, Inc.
Geotechnical Engineering
MTC Project No. 16S136
Yelm, WA 98597
Parcel #75300901200 & #75300901400
Borman Geotechnical & Infiltration Investigation
Log of Test Pit TP-1
(Page 1 of 1)
Date Started : 9/8/2016
Date Completed : 9/8/2016
Sampling Method : Grab Samples
Location : Approximately 48' from Rice St & 56' from Washington St
Logged By : CL
Depth in Feet0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15 USCSOL-SM
GP
OL-SW
SW
GW GRAPHICDESCRIPTION
TOPSOIL - SILTY SAND with GRAVEL, gravel up to 6 inches in diameter, organic debris
(brush, roots), very dry, medium dense to dense. DARK BROWN.
SANDY GRAVEL with trace SILT, cobbles up to 12 inches in diameter, minor roots, dry,
dense to very dense. TAN. (suspected uncontrolled fill)
SAND with GRAVEL, cobbles up to 12 inches in diameter, trace organic silts, burried
branches and old roots, dry, dense. GRAY-BROWN. (suspected old topsoil horizon)
SAND with GRAVEL, trace silt, cobbles up to 12 inches in diameter, dry, dense. LIGHT
BROWN.
GRAVEL with SAND, cobbles up to 18 inches in diameter, interbedded lenses of 3/8-to-3/4
inch gravel, dry, very dense. LIGHT BROWN.
TD 12.5' Test pit terminated at desired depth.
No Groundwater Encountered SamplesWater Level% Finer than #2003.3 % Moisture4.8
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
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11-09-2016 C:\Documents and Settings\Luke McCann\Desktop\GeoGraphics logs\Borman - TP-2 - CL, LM rev.borMaterials Testing & Consulting, Inc.
Geotechnical Engineering
MTC Project No. 16S136
Yelm, WA 98597
Parcel #75300901200 & #75300901400
Borman Geotechnical & Infiltration Investigation
Log of Test Pit TP-2
(Page 1 of 1)
Date Started : 9/8/2016
Date Completed : 9/8/2016
Sampling Method : Grab Samples
Location : Approximately 125' from Rice St & 35' from Washington St
Logged By : CL
Depth in Feet0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15 USCSOL-SM
GW
GP
GW GRAPHICDESCRIPTION
TOPSOIL - SILTY SAND with GRAVEL, gravel up to 6 inches in diameter, organic debris
(brush, roots), very dry, medium dense to dense. DARK BROWN.
SANDY GRAVEL with trace SILT, cobbles up to 10 inches in diameter, minor roots, dry,
loose to medium dense. BROWN. (suspected uncontrolled fill)
GRAVEL, cobbles up to 12 inches in diameter, trace sand and silt, roots, dry, medium dense
to dense. TAN.
GRAVEL with SAND, cobbles up to 18 inches in diameter, interbedded lenses of 3/8-to-3/4
inch gravel, dry, medium dense to dense. LIGHT BROWN.
TD 13.5' Test pit terminated at desired depth.
No Groundwater Encountered SamplesWater Level% Finer than #200% Moisture
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
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11-09-2016 C:\Documents and Settings\Luke McCann\Desktop\GeoGraphics logs\Borman - TP-3 - CL, LM rev.borMaterials Testing & Consulting, Inc.
Geotechnical Engineering
MTC Project No. 16S136
Yelm, WA 98597
Parcel #75300901200 & #75300901400
Borman Geotechnical & Infiltration Investigation
Log of Test Pit TP-3
(Page 1 of 1)
Date Started : 9/8/2016
Date Completed : 9/8/2016
Sampling Method : Grab Samples
Location : Approximately 190' from Rice St & 84' from Washington St
Logged By : CL
Depth in Feet0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15 USCSOL-SM
GW
GP
GW GRAPHICDESCRIPTION
TOPSOIL - SILTY SAND with GRAVEL, gravel up to 6 inches in diameter, organic debris
(brush, roots), very dry, loose to medium dense. DARK BROWN.
SANDY GRAVEL with trace SILT, cobbles up to 10 inches in diameter, minor roots, dry,
medium dense to dense. BROWN. (suspected uncontrolled fill)
GRAVEL, cobbles up to 18 inches in diameter, interbedded lenses of sand, dry, medium
dense to dense. TAN to ORANGISH-BROWN.
Interbedded SANDY lens between 3.5 to 5.0 feet.
GRAVEL with SAND, cobbles up to 18 inches in diameter, interbedded lenses of 3/8-to-3/4
inch gravel, dry,medium dense to very dense. LIGHT BROWN.
TD 12.0' Test pit terminated at desired depth.
No Groundwater Encountered SamplesWater Level% Finer than #2000.6
1.6 % Moisture5.9
4.0
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
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11-09-2016 C:\Documents and Settings\Luke McCann\Desktop\GeoGraphics logs\Borman - TP-4 - CL, LM rev.borMaterials Testing & Consulting, Inc.
Geotechnical Engineering
MTC Project No. 16S136
Yelm, WA 98597
Parcel #75300901200 & #75300901400
Borman Geotechnical & Infiltration Investigation
Log of Test Pit TP-4
(Page 1 of 1)
Date Started : 9/8/2016
Date Completed : 9/8/2016
Sampling Method : Grab Samples
Location : Approximately 210' from Rice St & 40' from Washington St
Logged By : CL
Depth in Feet0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15 USCSOL-SM
GP GRAPHICDESCRIPTION
TOPSOIL - SILTY SAND with GRAVEL, gravel up to 6 inches in diameter, organic debris
(brush, roots), very dry, loose to medium dense. DARK BROWN.
GRAVEL with SAND, cobbles up to 18 inches in diameter, interbedded lenses of sand and
gravel, roots to 4 feet BPG, dry, dense to very dense. LIGHT BROWN.
TD 12.0' Test pit terminated at desired depth.
No Groundwater Encountered SamplesWater Level% Finer than #200% MoistureGW
GW
GW
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
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WILDCAT DYNAMIC CONE LOG Page 1 of 1
Materials Testing and Consulting
2118 Black Lake Blvd., NW PROJECT NUMBER: 16S136
Olympia, WA 98512 DATE STARTED: 09-08-2016
DATE COMPLETED: 09-08-2016
HOLE #: DCP-1
CREW: CL SURFACE ELEVATION: Existing Grade
PROJECT: Borman Geotechnical & Infilitration Investigation
WATER ON COMPLETION:None Encountered
ADDRESS: Parcel #75300901200 & #75300901400, Yelm, WA HAMMER WEIGHT: 35 lbs.
LOCATION: Approximately 5 feet southeast of TP-1 CONE AREA: 10 sq. cm
BLOWS RESISTANCE GRAPH OF CONE RESISTANCE TESTED CONSISTENCY
DEPTH PER 10 cm Kg/cm² 0 50 100 150 N' SAND & SILT CLAY
- 5 22.2 •••••• 6 LOOSE MEDIUM STIFF
- 13 57.7 •••••••••••••••• 16 MEDIUM DENSE VERY STIFF
- 1 ft 31 137.6 ••••••••••••••••••••••••••••••••••••••• - DENSE HARD
- 34 151.0 ••••••••••••••••••••••••••••••••••••••••••• - DENSE HARD
- 50 222.0 •••••••••••••••••••••••••••••••••••••••••••••• - VERY DENSE HARD
- 2 ft
-
-
- 3 ft
- 1 m
-
- 4 ft
-
-
- 5 ft
-
-
- 6 ft
-
- 2 m
- 7 ft
-
-
- 8 ft
-
-
- 9 ft
-
-
- 3 m 10 ft
-
-
-
- 11 ft
-
-
- 12 ft
-
-
- 4 m 13 ft
WILDCAT.XLS
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
32
WILDCAT DYNAMIC CONE LOG Page 1 of 1
Materials Testing and Consulting
2118 Black Lake Blvd., NW PROJECT NUMBER: 16S136
Olympia, WA 98512 DATE STARTED: 09-08-2016
DATE COMPLETED: 09-08-2016
HOLE #: DCP-2
CREW: CL SURFACE ELEVATION:eginning 4.5 Feet BP
PROJECT: Borman Geotechnical & Infilitration Investigation
WATER ON COMPLETION:None Encountered
ADDRESS: Parcel #75300901200 & #75300901400, Yelm, WA HAMMER WEIGHT: 35 lbs.
LOCATION: Approximately 5 feet northwest of TP-2; Started 4.5 feet BPG CONE AREA: 10 sq. cm
BLOWS RESISTANCE GRAPH OF CONE RESISTANCE TESTED CONSISTENCY
DEPTH PER 10 cm Kg/cm² 0 50 100 150 N' SAND & SILT CLAY
- 0 0.0 0 VERY LOOSE VERY SOFT
- 0 0.0 0 VERY LOOSE VERY SOFT
- 1 ft 0 0.0 0 VERY LOOSE VERY SOFT
- 0 0.0 0 VERY LOOSE VERY SOFT
- 0 0.0 0 VERY LOOSE VERY SOFT
- 2 ft 0 0.0 0 VERY LOOSE VERY SOFT
- 0 0.0 0 VERY LOOSE VERY SOFT
- 0 0.0 0 VERY LOOSE VERY SOFT
- 3 ft 0 0.0 0 VERY LOOSE VERY SOFT
- 1 m 0 0.0 0 VERY LOOSE VERY SOFT
- 0 0.0 0 VERY LOOSE VERY SOFT
- 4 ft 0 0.0 0 VERY LOOSE VERY SOFT
- 0 0.0 0 VERY LOOSE VERY SOFT
- 0 0.0 0 VERY LOOSE VERY SOFT
- 5 ft 16 61.8 ••••••••••••••••• 17 MEDIUM DENSE VERY STIFF
- 15 57.9 •••••••••••••••• 16 MEDIUM DENSE VERY STIFF
- 11 42.5 •••••••••••• 12 MEDIUM DENSE STIFF
- 6 ft 9 34.7 •••••••••• 9 LOOSE STIFF
- 10 38.6 ••••••••••• 11 MEDIUM DENSE STIFF
- 2 m 12 46.3 ••••••••••••• 13 MEDIUM DENSE STIFF
- 7 ft 20 68.4 ••••••••••••••••••• 19 MEDIUM DENSE VERY STIFF
- 30 102.6 ••••••••••••••••••••••••••••• - MEDIUM DENSE VERY STIFF
- 43 147.1 •••••••••••••••••••••••••••••••••••••••••• - DENSE HARD
- 8 ft 43 147.1 •••••••••••••••••••••••••••••••••••••••••• - DENSE HARD
- 50 171.0 •••••••••••••••••••••••••••••••••••••••••••••• - DENSE HARD
-
- 9 ft
-
-
- 3 m 10 ft
-
-
-
- 11 ft
-
-
- 12 ft
-
-
- 4 m 13 ft
WILDCAT.XLS
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
33
WILDCAT DYNAMIC CONE LOG Page 1 of 1
Materials Testing and Consulting
2118 Black Lake Blvd., NW PROJECT NUMBER: 16S136
Olympia, WA 98512 DATE STARTED: 09-08-2016
DATE COMPLETED: 09-08-2016
HOLE #: DCP-3
CREW: CL SURFACE ELEVATION: Existing Grade
PROJECT: Borman Geotechnical & Infilitration Investigation
WATER ON COMPLETION:None Encountered
ADDRESS: Parcel #75300901200 & #75300901400, Yelm, WA HAMMER WEIGHT: 35 lbs.
LOCATION: Approximately 50 feet south of TP-2 CONE AREA: 10 sq. cm
BLOWS RESISTANCE GRAPH OF CONE RESISTANCE TESTED CONSISTENCY
DEPTH PER 10 cm Kg/cm² 0 50 100 150 N' SAND & SILT CLAY
- 3 13.3 ••• 3 VERY LOOSE SOFT
- 25 111.0 •••••••••••••••••••••••••••••••• - DENSE HARD
- 1 ft 50 222.0 •••••••••••••••••••••••••••••••••••••••••••••• - VERY DENSE HARD
-
-
- 2 ft
-
-
- 3 ft
- 1 m
-
- 4 ft
-
-
- 5 ft
-
-
- 6 ft
-
- 2 m
- 7 ft
-
-
- 8 ft
-
-
- 9 ft
-
-
- 3 m 10 ft
-
-
-
- 11 ft
-
-
- 12 ft
-
-
- 4 m 13 ft
WILDCAT.XLS
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
34
WILDCAT DYNAMIC CONE LOG Page 1 of 1
Materials Testing and Consulting
2118 Black Lake Blvd., NW PROJECT NUMBER: 16S136
Olympia, WA 98512 DATE STARTED: 09-08-2016
DATE COMPLETED: 09-08-2016
HOLE #: DCP-4
CREW: CL SURFACE ELEVATION: 4.5 Feet BPG
PROJECT: Borman Geotechnical & Infilitration Investigation
WATER ON COMPLETION:None Encountered
ADDRESS: Parcel #75300901200 & #75300901400, Yelm, WA HAMMER WEIGHT: 35 lbs.
LOCATION: Approximately 5 feet west of TP-3; Started 4.5 feet BPG CONE AREA: 10 sq. cm
BLOWS RESISTANCE GRAPH OF CONE RESISTANCE TESTED CONSISTENCY
DEPTH PER 10 cm Kg/cm² 0 50 100 150 N' SAND & SILT CLAY
- 0 0.0 0 VERY LOOSE VERY SOFT
- 0 0.0 0 VERY LOOSE VERY SOFT
- 1 ft 0 0.0 0 VERY LOOSE VERY SOFT
- 0 0.0 0 VERY LOOSE VERY SOFT
- 0 0.0 0 VERY LOOSE VERY SOFT
- 2 ft 0 0.0 0 VERY LOOSE VERY SOFT
- 0 0.0 0 VERY LOOSE VERY SOFT
- 0 0.0 0 VERY LOOSE VERY SOFT
- 3 ft 0 0.0 0 VERY LOOSE VERY SOFT
- 1 m 0 0.0 0 VERY LOOSE VERY SOFT
- 0 0.0 0 VERY LOOSE VERY SOFT
- 4 ft 0 0.0 0 VERY LOOSE VERY SOFT
- 0 0.0 0 VERY LOOSE VERY SOFT
- 0 0.0 0 VERY LOOSE VERY SOFT
- 5 ft 19 73.3 ••••••••••••••••••••• 20 MEDIUM DENSE VERY STIFF
- 20 77.2 •••••••••••••••••••••• 22 MEDIUM DENSE VERY STIFF
- 50 193.0 •••••••••••••••••••••••••••••••••••••••••••••• - VERY DENSE HARD
- 6 ft
-
- 2 m
- 7 ft
-
-
- 8 ft
-
-
- 9 ft
-
-
- 3 m 10 ft
-
-
-
- 11 ft
-
-
- 12 ft
-
-
- 4 m 13 ft
WILDCAT.XLS
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
35
WILDCAT DYNAMIC CONE LOG Page 1 of 1
Materials Testing and Consulting
2118 Black Lake Blvd., NW PROJECT NUMBER: 16S136
Olympia, WA 98512 DATE STARTED: 09-08-2016
DATE COMPLETED: 09-08-2016
HOLE #: DCP-5
CREW: CL SURFACE ELEVATION: Existing Grade
PROJECT: Borman Geotechnical & Infilitration Investigation
WATER ON COMPLETION:None Encountered
ADDRESS: Parcel #75300901200 & #75300901400, Yelm, WA HAMMER WEIGHT: 35 lbs.
LOCATION: Approximately 5 feet north of TP-4 CONE AREA: 10 sq. cm
BLOWS RESISTANCE GRAPH OF CONE RESISTANCE TESTED CONSISTENCY
DEPTH PER 10 cm Kg/cm² 0 50 100 150 N' SAND & SILT CLAY
-28.9•• 2VERY LOOSESOFT
- 25 111.0 •••••••••••••••••••••••••••••••• - DENSE HARD
- 1 ft 16 71.0 •••••••••••••••••••• 20 MEDIUM DENSE VERY STIFF
- 16 71.0 •••••••••••••••••••• 20 MEDIUM DENSE VERY STIFF
- 30 133.2 •••••••••••••••••••••••••••••••••••••• - DENSE HARD
- 2 ft 50 222.0 •••••••••••••••••••••••••••••••••••••••••••••• - VERY DENSE HARD
-
-
- 3 ft
- 1 m
-
- 4 ft
-
-
- 5 ft
-
-
- 6 ft
-
- 2 m
- 7 ft
-
-
- 8 ft
-
-
- 9 ft
-
-
- 3 m 10 ft
-
-
-
- 11 ft
-
-
- 12 ft
-
-
- 4 m 13 ft
WILDCAT.XLS
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
36
Appendix D. LABORATORY RESULTS
Laboratory tests were conducted on several representative soil samples to better identify the soil
classification of the units encountered and to evaluate the material's general physical properties and
engineering characteristics. A brief description of the tests performed for this study is provided below.
The results of laboratory tests performed on specific samples are provided at the appropriate sample
depths on the individual boring logs. However, it is important to note that these test results may not
accurately represent in situ soil conditions. All of our recommendations are based on our interpretation
of these test results and their use in guiding our engineering judgment. MTC cannot be responsible for
the interpretation of these data by others.
Soil samples for this project will be retained for a period of 30 days following completion of this report,
unless we are otherwise directed in writing.
SOIL CLASSIFICATION
Soil samples were visually examined in the field by our geologist at the time they were obtained. They
were subsequently packaged and returned to our laboratory where they were reexamined and the original
description checked and verified or modified. With the help of information obtained from the other
classification tests, described below, the samples were described in general accordance with ASTM
Standard D2487. The resulting descriptions are provided at the appropriate locations on the individual
exploration logs, located in Appendix C, and are qualitative only.
GRAIN-SIZE DISTRIBUTION
Grain-size distribution analyses were conducted in general accordance with ASTM Standard D422 on
representative soil samples to determine the grain-size distribution of the on-site soil. The information
gained from these analyses allows us to provide a description and classification of the in-place materials.
In turn, this information helps us to understand engineering properties of the soil and thus how the in-
place materials will behave under conditions such as stormwater innundation, traffic action, loading,
potential liquefaction, and so forth. The results are presented in this Appendix.
NATURAL MOISTURE CONTENT
Moisture content tests were performed in general accordance with ASTM Standard D2216 on
representative soil samples to approximately ascertain the in-place moisture content of soil samples at
the times they were collected. The information obtained assists us by providing qualitative information
regarding soil compactability. The results are presented in this Appendix.
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
37
Project: Date Received:23-Sep-16
Project #: Sampled By:CL
Client: Date Tested:26-Sep-16
Source: Tested By:JE
Sample#:S16-578
D(5) =0.163 mm % Gravel =68.6%Coeff. of Curvature, CC =1.41
Specifications D(10) =0.295 mm % Sand =28.1%Coeff. of Uniformity, CU =104.21
No Specs D(15) =0.402 mm % Silt & Clay =3.3%Fineness Modulus =6.10
Sample Meets Specs ?N/A D(30) =3.574 mm Liquid Limit =n/a Plastic Limit =n/a
D(50) =21.877 mm Plasticity Index =n/a Moisture %, as sampled =4.8%
D(60) =30.768 mm Sand Equivalent =n/a Req'd Sand Equivalent =
D(90) =51.003 mm Fracture %, 1 Face =n/a Req'd Fracture %, 1 Face =
Dust Ratio =17/82 Fracture %, 2+ Faces =n/a Req'd Fracture %, 2+ Faces =
Actual Interpolated
Cumulative Cumulative
Sieve Size Percent Percent Specs Specs
US Metric Passing Passing Max Min
12.00" 300.00 100% 100.0% 0.0%
10.00" 250.00 100% 100.0% 0.0%
8.00" 200.00 100% 100.0% 0.0%
6.00" 150.00 100% 100.0% 0.0%
4.00" 100.00 100% 100.0% 0.0%
3.00" 75.00 100% 100.0% 0.0%
2.50" 63.00 100% 100% 100.0% 0.0%
2.00" 50.00 89% 89% 100.0% 0.0%
1.75" 45.00 89% 89% 100.0% 0.0%
1.50" 37.50 67% 67% 100.0% 0.0%
1.25" 31.50 61% 61% 100.0% 0.0%
1.00" 25.00 54% 54% 100.0% 0.0%
3/4" 19.00 46% 46% 100.0% 0.0%
5/8" 16.00 44% 44% 100.0% 0.0%
1/2" 12.50 40% 40% 100.0% 0.0%
3/8" 9.50 37% 37% 100.0% 0.0%
1/4" 6.30 33% 33% 100.0% 0.0%
#4 4.75 31% 31% 100.0% 0.0%
#8 2.36 29% 100.0% 0.0%
#10 2.00 28% 28% 100.0% 0.0%
#16 1.18 24% 100.0% 0.0%
#20 0.850 23% 23% 100.0% 0.0%
#30 0.600 19% 100.0% 0.0%
#40 0.425 16% 16% 100.0% 0.0%
#50 0.300 10% 100.0% 0.0%
#60 0.250 8% 8% 100.0% 0.0%
#80 0.180 5% 5% 100.0% 0.0%
#100 0.150 5% 5% 100.0% 0.0%
#140 0.106 4% 100.0% 0.0%
#170 0.090 4% 100.0% 0.0%
#200 0.075 3.3% 3.3% 100.0% 0.0%
Copyright Spears Engineering & Technical Services PS, 1996-98
TP-1 @ 10'
ASTM D-2487 Unified Soils Classification System
ASTM D-2216, ASTM D-2419, ASTM D-4318, ASTM D-5821
Sieve Report
GW, Well-graded Gravel with Sand
Brown
Sample Color:
Borman Residential Geotech Study
ASTM C-136, ASTM D-6913
16S136
Seth Borman
8"6"4"2"3"1½"1¼"10"1"¾"5/8"½"3/8"¼"#4#8#10#16#20#30#40#50#60#80#100#140#170#2000%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.0%
10.0%
20.0%
30.0%
40.0%
50.0%
60.0%
70.0%
80.0%
90.0%
100.0%
0.0010.0100.1001.00010.000100.000% Passing% PassingParticle Size (mm)
Grain Size Distribution
Sieve Sizes Max Specs Min Specs Sieve Results
Materials Testing & Consulting, Inc.
2118 Black Lake Blvd. SW
Olympia, WA 98512
Lab Sample: TP-1 @ 10.0’
Proposed Borman Residential
Rice St SW & Washington St SW
Yelm, Washington
FIGURE
4
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
38
Project: Date Received:23-Sep-16
Project #: Sampled By:CL
Client: Date Tested:26-Sep-16
Source: Tested By:JE
Sample#:S16-579
D(5) =0.239 mm % Gravel =68.8%Coeff. of Curvature, CC =1.32
Specifications D(10) =0.365 mm % Sand =29.5%Coeff. of Uniformity, CU =90.62
No Specs D(15) =0.552 mm % Silt & Clay =1.6%Fineness Modulus =6.16
Sample Meets Specs ?N/A D(30) =3.980 mm Liquid Limit =n/a Plastic Limit =n/a
D(50) =22.693 mm Plasticity Index =n/a Moisture %, as sampled =4.0%
D(60) =33.039 mm Sand Equivalent =n/a Req'd Sand Equivalent =
D(90) =44.439 mm Fracture %, 1 Face =n/a Req'd Fracture %, 1 Face =
Dust Ratio =10/77 Fracture %, 2+ Faces =n/a Req'd Fracture %, 2+ Faces =
Actual Interpolated
Cumulative Cumulative
Sieve Size Percent Percent Specs Specs
US Metric Passing Passing Max Min
12.00" 300.00 100% 100.0% 0.0%
10.00" 250.00 100% 100.0% 0.0%
8.00" 200.00 100% 100.0% 0.0%
6.00" 150.00 100% 100.0% 0.0%
4.00" 100.00 100% 100.0% 0.0%
3.00" 75.00 100% 100.0% 0.0%
2.50" 63.00 100% 100% 100.0% 0.0%
2.00" 50.00 92% 92% 100.0% 0.0%
1.75" 45.00 92% 92% 100.0% 0.0%
1.50" 37.50 64% 64% 100.0% 0.0%
1.25" 31.50 58% 58% 100.0% 0.0%
1.00" 25.00 52% 52% 100.0% 0.0%
3/4" 19.00 47% 47% 100.0% 0.0%
5/8" 16.00 43% 43% 100.0% 0.0%
1/2" 12.50 40% 40% 100.0% 0.0%
3/8" 9.50 38% 38% 100.0% 0.0%
1/4" 6.30 33% 33% 100.0% 0.0%
#4 4.75 31% 31% 100.0% 0.0%
#8 2.36 28% 100.0% 0.0%
#10 2.00 27% 27% 100.0% 0.0%
#16 1.18 23% 100.0% 0.0%
#20 0.850 21% 21% 100.0% 0.0%
#30 0.600 16% 100.0% 0.0%
#40 0.425 12% 12% 100.0% 0.0%
#50 0.300 7% 100.0% 0.0%
#60 0.250 5% 5% 100.0% 0.0%
#80 0.180 3% 3% 100.0% 0.0%
#100 0.150 3% 3% 100.0% 0.0%
#140 0.106 2% 100.0% 0.0%
#170 0.090 2% 100.0% 0.0%
#200 0.075 1.6% 1.6% 100.0% 0.0%
Copyright Spears Engineering & Technical Services PS, 1996-98
TP-3 @ 6'
ASTM D-2487 Unified Soils Classification System
ASTM D-2216, ASTM D-2419, ASTM D-4318, ASTM D-5821
Sieve Report
GW, Well-graded Gravel with Sand
Brown
Sample Color:
Borman Residential Geotech Study
ASTM C-136, ASTM D-6913
16S136
Seth Borman
8"6"4"2"3"1½"1¼"10"1"¾"5/8"½"3/8"¼"#4#8#10#16#20#30#40#50#60#80#100#140#170#2000%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.0%
10.0%
20.0%
30.0%
40.0%
50.0%
60.0%
70.0%
80.0%
90.0%
100.0%
0.0010.0100.1001.00010.000100.000% Passing% PassingParticle Size (mm)
Grain Size Distribution
Sieve Sizes Max Specs Min Specs Sieve Results
Materials Testing & Consulting, Inc.
2118 Black Lake Blvd. SW
Olympia, WA 98512
Lab Sample: TP-3 @ 3.0’
Proposed Borman Residential
Rice St SW & Washington St SW
Yelm, Washington
FIGURE
5
Borman Residential Geotechnical Investigation Materials Testing & Consulting, Inc.
December 12, 2016 Project No.: 16S136
39
Project: Date Received:23-Sep-16
Project #: Sampled By:CL
Client: Date Tested:26-Sep-16
Source: Tested By:JE
Sample#:S16-579
D(5) =0.308 mm % Gravel =87.7%Coeff. of Curvature, CC =12.01
Specifications D(10) =0.803 mm % Sand =11.7%Coeff. of Uniformity, CU =35.47
No Specs D(15) =7.170 mm % Silt & Clay =0.6%Fineness Modulus =6.98
Sample Meets Specs ?N/A D(30) =16.581 mm Liquid Limit =n/a Plastic Limit =n/a
D(50) =25.472 mm Plasticity Index =n/a Moisture %, as sampled =5.9%
D(60) =28.499 mm Sand Equivalent =n/a Req'd Sand Equivalent =
D(90) =40.746 mm Fracture %, 1 Face =n/a Req'd Fracture %, 1 Face =
Dust Ratio =7/92 Fracture %, 2+ Faces =n/a Req'd Fracture %, 2+ Faces =
Actual Interpolated
Cumulative Cumulative
Sieve Size Percent Percent Specs Specs
US Metric Passing Passing Max Min
12.00" 300.00 100% 100.0% 0.0%
10.00" 250.00 100% 100.0% 0.0%
8.00" 200.00 100% 100.0% 0.0%
6.00" 150.00 100% 100.0% 0.0%
4.00" 100.00 100% 100.0% 0.0%
3.00" 75.00 100% 100.0% 0.0%
2.50" 63.00 100% 100.0% 0.0%
2.00" 50.00 100% 100.0% 0.0%
1.75" 45.00 100% 100% 100.0% 0.0%
1.50" 37.50 82% 82% 100.0% 0.0%
1.25" 31.50 70% 70% 100.0% 0.0%
1.00" 25.00 48% 48% 100.0% 0.0%
3/4" 19.00 35% 35% 100.0% 0.0%
5/8" 16.00 29% 29% 100.0% 0.0%
1/2" 12.50 22% 22% 100.0% 0.0%
3/8" 9.50 18% 18% 100.0% 0.0%
1/4" 6.30 14% 14% 100.0% 0.0%
#4 4.75 12% 12% 100.0% 0.0%
#8 2.36 11% 100.0% 0.0%
#10 2.00 11% 11% 100.0% 0.0%
#16 1.18 10% 100.0% 0.0%
#20 0.850 10% 10% 100.0% 0.0%
#30 0.600 9% 100.0% 0.0%
#40 0.425 8% 8% 100.0% 0.0%
#50 0.300 5% 100.0% 0.0%
#60 0.250 4% 4% 100.0% 0.0%
#80 0.180 2% 2% 100.0% 0.0%
#100 0.150 2% 2% 100.0% 0.0%
#140 0.106 1% 100.0% 0.0%
#170 0.090 1% 100.0% 0.0%
#200 0.075 0.6% 0.6% 100.0% 0.0%
Copyright Spears Engineering & Technical Services PS, 1996-98
TP-3 @ 3'
ASTM D-2487 Unified Soils Classification System
ASTM D-2216, ASTM D-2419, ASTM D-4318, ASTM D-5821
Sieve Report
GP, Poorly graded Gravel
Brown
Sample Color:
Borman Residential Geotech Study
ASTM C-136, ASTM D-6913
16S136
Seth Borman
8"6"4"2"3"1½"1¼"10"1"¾"5/8"½"3/8"¼"#4#8#10#16#20#30#40#50#60#80#100#140#170#2000%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0.0%
10.0%
20.0%
30.0%
40.0%
50.0%
60.0%
70.0%
80.0%
90.0%
100.0%
0.0010.0100.1001.00010.000100.000% Passing% PassingParticle Size (mm)
Grain Size Distribution
Sieve Sizes Max Specs Min Specs Sieve Results
Materials Testing & Consulting, Inc.
2118 Black Lake Blvd. SW
Olympia, WA 98512
Lab Sample: TP-3 @ 6.0’
Proposed Borman Residential
Rice St SW & Washington St SW
Yelm, Washington
FIGURE
6