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GEOTECHNICAL ENGINEERING REPORT
of
Caldera Canyon
1294 East Leigh Field Drive
Meridian, ID
Prepared for:
Randy Sohn
I294 East Leigh Field Drive
Meridian, ID 83646
Mn File Number 8190036g
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Mr. Randy Sohn
1294 East Leigh Field Drive
Meridian, ID 83646
208-995-9034
Re: Geotechnical Engineering Report
Caldera Canyon
1294 East Leigh Field Drive
Meridian, ID
Dear Mr. Sohn:
In compliance with your instructions, MTI has conducted a soils exploration and foundation evaluation for the
above referenced development. Fieldwork for this investigation was conducted on 7 January 2019. Data have
been analyzed to evaluate pertinent geotechnical conditions. Results of this investigation, together with our
recommendations, are to be found in the following report. We have provided a PDF copy for your review and
distribution.
Often, questions arise concerning soil conditions because of design and construction details that occur on a
project. MTI would be pleased to continue our role as geotechnical engineers during project implementation.
Additionally, MTI can provide materials testing and special inspection services during construction of this
project. If you will advise us of the appropriate time to discuss these engineering services, we will meet with
you at your convenience.
MTI appreciates this opportunity to be of service to you and looks forward to working with you in the future.
If you have questions, please call (208) 376-4748.
Respectfully Submitted,
Materials Testing & Inspection
a
Maren Tanberg, E.I.T., G.I.T.
Staff Engineer and Geologist
l ��
Revier-ved by: Eli abeth Br(
Geotechnical
Reviewed by: Monica Sacul es, P.E.
Senior Geotechnical Engineer
cc: Dewitt Kerner, Rock Solid Civil (PDF Copy); Vanessa Klaus (PDF Copy)
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TABLE OF CONTENTS
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INTRODUCTION...............................................................................................................................................................3
ProjectDescription.................................................................................................................................................3
Authorization..........................................................................................................................................................3
Purpose...................................................................................................................................................................3
Scopeof Investigation............................................................................................................................................3
Warrantyand Limiting Conditions.........................................................................................................................4
SITEDESCRIPTION..........................................................................................................................................................5
SiteAccess..............................................................................................................................................................5
RegionalGeology...................................................................................................................................................5
GeneralSite Characteristics....................................................................................................................................5
Regional Site Climatology and Geochemistry........................................................................................................6
SEISMICSITE EVALUATION............................................................................................................................................6
GeoseismicSetting.................................................................................................................................................6
SeismicDesign Parameter Values..........................................................................................................................6
SOILSEXPLORATION......................................................................................................................................................7
Explorationand Sampling Procedures....................................................................................................................7
LaboratoryTesting Program...................................................................................................................................7
Soiland Sediment Profile.......................................................................................................................................8
VolatileOrganic Scan.............................................................................................................................................8
SITEHYDROLOGY...........................................................................................................................................................8
Groundwater...........................................................................................................................................................9
SoilInfiltration Rates..............................................................................................................................................9
FOUNDATION, SLAB, AND PAVEMENT DISCUSSION AND RECOMMENDATIONS
...............................................................9
Foundation Design Recommendations.................................................................................................................10
CrawlSpace Recommendations...........................................................................................................................1
I
Floor, Patio, and Garage Slab-on-Grade...............................................................................................................1
l
RecommendedPavement Sections.......................................................................................................................11
FlexiblePavement Section...................................................................................................................................12
PavementSubgrade Preparation...........................................................................................................................12
Common Pavement Section Construction Issues.................................................................................................12
CONSTRUCTIONCONSIDERATIONS...............................................................................................................................13
Earthwork.............................................................................................................................................................13
DryWeather.........................................................................................................................................................14
WetWeather.........................................................................................................................................................14
SoftSubgrade Soils..............................................................................................................................................14
FrozenSubgrade Soils..........................................................................................................................................15
StructuralFill........................................................................................................................................................15
Backfillof Walls...................................................................................................................................................16
Excavations...........................................................................................................................................................16
GroundwaterControl............................................................................................................................................17
GENERALCOMMENTS..................................................................................................................................................17
REFERENCES.................................................................................................................................................................18
APPENDICES.................................................................................................................................................................19
AcronymList........................................................................................................................................................19
GeotechnicalGeneral Notes.................................................................................................................................20
Geotechnical Investigation Test Pit Log...............................................................................................................21
AASHTO Pavement Thickness Design Procedures.............................................................................................24
R -Value Laboratory Test Data..............................................................................................................................25
Plate1: Vicinity Map............................................................................................................................................26
Plate2: Site Map...................................................................................................................................................27
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INTRODUCTION
This report presents results of a geotechnical investigation and analysis in support of data utilized in design of
structures as defined in the 2015 International Building Code (IBC). Information in support of groundwater
and stormwater issues pertinent to the practice of Civil Engineering is included. Observations and
recommendations relevant to the earthwork phase of the project are also presented. Revisions in plans or
drawings for the proposed development from those enumerated in this report should be brought to the attention
of the soils engineer to determine whether changes in the provided recommendations are required. Deviations
from noted subsurface conditions, if encountered during construction, should also be brought to the attention of
the soils engineer.
Project Description
The proposed development is in the northeast portion of the City of Meridian, Ada County, ID, and occupies a
portion of the SE'/4NEt/4 of Section 31, Township 4 North, Range 1 East, Boise Meridian. This project will
consist of developing a 13 lot residential subdivision with associated private streets. The site to be development
is approximately 2.05 acres in size. Total settlements are limited to 1 inch. Loads of up to 4,000 pounds per
lineal foot for wall footings, and column loads of up to 50,000 pounds were assumed for settlement calculations.
Additionally, assumptions have been made for traffic loading of pavements. Retaining walls are not anticipated
as part of the project. MTI has not been informed of the proposed grading plan.
Authorization
Authorization to perform this exploration and analysis was given in the form of a written authorization to
proceed from Mr. Randy Sohn to Monica Saculles of Materials Testing and Inspection (MTI), on 20 December
2018. Said authorization is subject to terms, conditions, and limitations described in the Professional Services
Contract entered into between and MTI. Our scope of services for the proposed development has been provided
in our proposal dated 19 December 2018 and repeated below.
Purpose
The purpose of this Geotechnical Engineering Report is to determine various soil profile components and their
engineering characteristics for use by either design engineers or architects in:
• Preparing or verifying suitability of foundation design and placement
• Preparing site drainage designs
• Indicating issues pertaining to earthwork construction
• Preparing residential pavement section design requirements
Scope of Investigation
The scope of this investigation included review of geologic literature and existing available geotechnical studies
of the area, visual site reconnaissance of the immediate site, subsurface exploration of the site, field and
laboratory testing of materials collected, and engineering analysis and evaluation of foundation materials.
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Warranty and Limiting Conditions
MTI warrants that findings and conclusions contained herein have been formulated in accordance with generally
accepted professional engineering practice in the fields of foundation engineering, soil mechanics, and
engineering geology only for the site and project described in this report. These engineering methods have been
developed to provide the client with information regarding apparent or potential engineering conditions relating
to the site within the scope cited above and are necessarily limited to conditions observed at the time of the site
visit and research. Field observations and research reported herein are considered sufficient in detail and scope
to form a reasonable basis for the purposes cited above.
Exclusive Use
This report was prepared for exclusive use of the property owner(s), at the time of the report, and their
retained design consultants ("Client"). Conclusions and recommendations presented in this report are based
on the agreed-upon scope of work outlined in this report together with the Contract for Professional Services
between the Client and Materials Testing and Inspection ("Consultant"). Use or misuse of this report, or reliance
upon findings hereof, by patties other than the Client is at their own risk. Neither Client nor Consultant make
representation of warranty to such other parties as to accuracy or completeness of this report or suitability of its
use by such other parties for purposes whatsoever, known or unknown, to Client or Consultant. Neither Client
nor Consultant shall have liability to indemnify or hold harmless third parties for losses incurred by actual or
purported use or misuse of this report. No other warranties are implied or expressed.
Report Recommendations are Limited and Subject to Misinterpretation
There is a distinct possibility that conditions may exist that could not be identified within the scope of the
investigation or that were not apparent during our site investigation. Findings of this report are limited to data
collected from noted explorations advanced and do not account for unidentified fill zones, unsuitable soil types
or conditions, and variability in soil moisture and groundwater conditions. To avoid possible misinterpretations
of findings, conclusions, and implications of this report, MTI should be retained to explain the report contents
to other design professionals as well as construction professionals.
Since actual subsurface conditions on the site can only be verified by earthwork, note that construction
recommendations are based on general assumptions from selective observations and selective field exploratory
sampling. Upon commencement of construction, such conditions may be identified that require corrective
actions, and these required corrective actions may impact the project budget. Therefore, construction
recommendations in this report should be considered preliminary, and MTI should be retained to observe actual
subsurface conditions during earthwork construction activities to provide additional construction
recommendations as needed.
Since geotechnical reports are subject to misinterpretation, do not separate the soil logs from the report. Rather,
provide a copy of, or authorize for their use, the complete report to other design professionals or contractors.
Locations of exploratory sites referenced within this report should be considered approximate locations only.
For more accurate locations, services of a professional land surveyor are recommended.
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This report is also limited to information available at the time it was prepared. In the event additional
information is provided to MTI following publication of our report, it will be forwarded to the client for
evaluation in the form received.
Environmental Concerns
Comments in this report concerning either onsite conditions or observations, including soil appearances and
odors, are provided as general information. These comments are not intended to describe, quantify, or evaluate
environmental concerns or situations. Since personnel, skills, procedures, standards, and equipment differ, a
geotechnical investigation report is not intended to substitute for a geoenvironmental investigation or a Phase
II/11I Environmental Site Assessment. If environmental services are needed, MTI can provide, via a separate
contract, those personnel who are trained to investigate and delineate soil and water contamination.
SITE DESCRIPTION
Site Access
Access to the site may be gained via Interstate 84 to the Eagle Road exit. Proceed north on Eagle Road
approximately 2.5 miles to its intersection with Ustick Road. From this intersection, drive west 1 mile to Locust
Grove Road. Continue north on Locust Grove Road for t/2 -mile to Leigh Field Drive. Proceed west on Leigh
Field Drive for 0.17 mile. The site is north of Leigh Field Drive. Presently the site exists as a pasture. The
location is depicted on site map plates included in the Appendix.
Regional Geology
The project site is located within the western Snake River Plain of southwestern Idaho and eastern Oregon. The
plain is a northwest trending rift basin, about 45 miles wide and 200 miles long, that developed about 14 million
years ago (Ma) and has since been occupied sporadically by large inland lakes. Geologic materials found within
and along the plain's margins reflect volcanic and fluvial/lacustrine sedimentary processes that have led to an
accumulation of approximately 1 to 2 km of interbedded volcanic and sedimentary deposits within the plain.
Along the margins of the plain, streams that drained the highlands to the north and south provided coarse to
fine-grained sediments eroded from granitic and volcanic rocks, respectively. About 2 million years ago the
last of the lakes was drained and since that time fluvial erosion and deposition has dominated the evolution of
the landscape. The project site is underlain by the "Gravel of Whitney Terrace" as mapped by Othberg and
Stanford (1993). Sediments of the Whitney terrace consist of sandy pebble and cobble gravel. The Whitney
terrace is the second terrace above modern Boise River floodplain, is thickest toward its eastern extent, and is
mantled with 2-6 feet of loess.
General Site Characteristics
This proposed development consists of approximately 2.05 acres of relatively flat terrain. The site is primarily
used for pasture. Throughout the majority of the site, surficial soils consist of lean clays. Vegetation primarily
consists of a few mature trees, bunchgrass, and other native grass varieties typical of arid to semi -arid
environments.
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Regional drainage is north and west toward the Boise River. Stormwater drainage for the site is achieved by
percolation through surfcial soils. The site is situated so that it is unlikely that it will receive any stormwater
drainage from off-site sources. Stormwater drainage collection and retention systems were not noted on the
project site, but do exist along Leigh Field Drive in the form of curbs, gutters, and drop inlets.
Regional Site Climatology and Geochemistry
According to the Western Regional Climate Center, the average precipitation for the Treasure Valley is on the
order of 10 to 12 inches per year, with an annual snowfall of approximately 20 inches and a range from 3 to 49
inches. The monthly mean daily temperatures range from 21°F to 95°F, with daily extremes ranging from -
25°F to 111°F. Winds are generally from the northwest or southeast with an annual average wind speed of
approximately 9 miles per hour (mph) and a maximum of 62 mph. Soils and sediments in the area are primarily
derived from siliceous materials and exhibit low electro -chemical potential for corrosion of metals or concretes.
Local aggregates are generally appropriate for Portland cement and lime cement mixtures. Surface water,
groundwater, and soils in the region typically have pH levels ranging from 7.2 to 8.2.
SEISMIC SITE EVALUATION
Geoseismic Setting
Soils on site are classed as Site Class D in accordance with Chapter 20 of the American Society of Civil
Engineers (ASCE) publication ASCE/SEI 7-10. Structures constructed on this site should be designed per IBC
requirements for such a seismic classification. Our investigation did not reveal hazards resulting from potential
earthquake motions including: slope instability, liquefaction, and surface rupture caused by faulting or lateral
spreading. Incidence and anticipated acceleration of seismic activity in the area is low.
Seismic Design Parameter Values
The United States Geological Survey National Seismic Hazard Maps (2008), includes a peak ground
acceleration map. The map for 2% probability of exceedance in 50 years in the Western United States in
standard gravity (g) indicates that a peals ground acceleration of 0.201 is appropriate for the project site based
on a Site Class D.
The following section provides an assessment of the earthquake -induced earthquake loads for the site based on
the Risk -Targeted Maximum Considered Earthquake (MCER). The NICER spectral response acceleration for
short periods, Sais, and at 1 -second period, &II, are adjusted for site class effects as required by the 2015 IBC.
Design spectral response acceleration parameters as presented in the 2015 IBC are defined as a 5% damped
design spectral response acceleration at short periods, SDs, and at 1 -second period, SDI.
The USGS National Seismic Hazards Mapping Project includes a program that provides values for ground
motion at a selected site based on the same data that were used to prepare the USGS ground motion maps. The
maps were developed using attenuation relationships for soft rock sites; the source model, assumptions, and
empirical relationships used in preparation of the maps are described in Petersen and others (1996).
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Seismic Desi n Values
Seismic Desi n Parameter
Desi n Value
Site Class
D "Stiff Soil"
SS
0.296 (g)
Si
0.104 (g)
Fa
1.563
F,,
2.386
SMS
0.463
SMI
0.247
SDs
0.309
SDI
0.165
SOILS EXPLORATION
Exploration and Sampling Procedures
Field exploration conducted to determine engineering characteristics of subsurface materials included a
reconnaissance of the project site and investigation by test pit. Test pit sites were located in the field by means
of a Global Positioning System (GPS) device and are reportedly accurate to within fifteen feet. Upon
completion of investigation, each test pit was backfilled with loose excavated materials. Re -excavation and
compaction of these test pit areas are required prior to construction of overlying structures.
In addition, samples were obtained from representative soil strata encountered. Samples obtained have been
visually classified in the field by professional staff, identified according to test pit number and depth, placed in
sealed containers, and transported to our laboratory for additional testing. Subsurface materials have been
described in detail on logs provided in the Appendix. Results of field and laboratory tests are also presented in
the Appendix. MTI recommends that these logs not be used to estimate fill material quantities.
Laboratory Testing Program
Along with our field investigation, a supplemental laboratory testing program was conducted to determine
additional pertinent engineering characteristics of subsurface materials necessary in an analysis of anticipated
behavior of the proposed structures. Laboratory tests were conducted in accordance with current applicable
American Society for Testing and Materials (ASTM) and American Association of State Highway and
Transportation Officials (AASHTO) specifications, and results of these tests are to be found on the
accompanying logs located in the Appendix. The laboratory testing program for this report included: Atterberg
Limits Testing — ASTM D4318, Grain Size Analysis — ASTM C 117/C 136, and Resistance Value (R -value) and
Expansion Pressure of Compacted Soils — Idaho T-8.
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Soil and Sediment Profile
The profile below represents a generalized interpretation for the project site. Note that on site soils strata,
encountered between test pit locations, may vary from the individual soil profiles presented in the logs, which
can be found in the Appendix.
The materials encountered during exploration were quite typical for the geologic area mapped as Gravel of
Whitney Terrace. Lean clay soils were encountered at ground surface. These soils were brown to dark brown,
moist, and medium stiff to very stiff. Organic materials and disturbed materials, as a result of plowing activities,
usually reached a depth of 1.1 feet. In test pit 2, silt was encountered below the lean clay. The silt was dark
brown, slightly moist, very stiff, and contained fine-grained sand. Below the silt in test pit 2 and lean clays in
test pits 1 and 3, sandy silt was encountered. The sandy silt was brown to light brown, dry to moist, very stiff
to hard, and contained fine to medium -grained sand. This soil horizon also contained some varying degrees of
calcium carbonate cementation (hardpan).
In test pit 3, silty sand and poorly graded sand was encountered below the sandy silt. The silty sand was brown
to red brown, dry to slightly moist, dense to very dense, and contained fine to coarse-grained sand. The poorly
graded sand was light brown, dry, medium dense, and contained fine to coarse-grained sand. In test pits 1 and
2, poorly graded gravel with silt and sand was encountered below the silty sand. The poorly graded gravel with
silt and sand was brown, dry to slightly moist, dense to very dense, and contained fine to coarse grained sand,
fine to coarse gravel, and 5 -inch -minus cobbles. At depth, poorly graded gravel with sand was encountered. The
poorly graded gravel with sand was light brown, dry, medium dense to dense, and contained fine to coarse-
grained sand, fine to coarse gravel, and 12 -inch -minus cobbles.
Competency of test pit sidewalls varied little across the site. In general, fine grained soils remained stable while
more granular sediments readily sloughed. However, moisture contents will also affect wall competency with
saturated soils having a tendency to readily slough when under load and unsupported.
Volatile Organic Scan
No environmental concerns were identified prior to commencement of the investigation. Therefore, soils
obtained during on-site activities were not assessed for volatile organic compounds by portable photoionization
detector. Samples obtained during our exploration activities exhibited no odors or discoloration typically
associated with this type of contamination. No groundwater was encountered.
SITE HYDROLOGY
Existing surface drainage conditions are defined in the General Site Characteristics section. Information
provided in this section is limited to observations made at the time of the investigation. Either regional or local
ordinances may require information beyond the scope of this report.
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Groundwater
During this field investigation, groundwater was not encountered in test pits advanced to a maximum depth of
16.1 feet bgs. Soil moistures in the test pits were generally moist within surficial soils, and lessened in moisture
content with depth. In the vicinity of the project site, groundwater levels are controlled in large part by
residential irrigation activity and leakage from nearby canals. Maximum groundwater elevations likely occur
during the later portion of the irrigation season.
During previous investigations performed in September 2005, February and July 2016, and August 2017 within
approximately t/3 -mile to the southeast and south of the project site, no evidence of groundwater was noted
within numerous test pits advanced to depths as great as 10.8 to 15.8 feet bgs. Furthermore, according to Idaho
Department of Water Resources (IDWR) monitoring well data 0.1 -mile south of the project site, groundwater
was measured at a depth at 22 feet bgs.
Based on evidence of this investigation and background knowledge of the area, MTI estimates groundwater
depths to remain greater than approximately 15 feet bgs throughout the year. This depth can be confirmed
through long-term groundwater monitoring.
Soil Infiltration Rates
Soil permeability, which is a measure of the ability of a soil to transmit a fluid, was not tested in the field. Given
the absence of direct measurements, for this report an estimation of infiltration is presented using generally
recognized values for each soil type and gradation. Of soils comprising the generalized soil profile for this
study, lean clay and silt soils generally offer little permeability, with typical hydraulic infiltration rates of less
than 2 inches per hour. Sandy silt soils will commonly exhibit infiltration rates from 2 to 4 inches per hour;
though calcium carbonate cementation may reduce this value to near zero. Silty sand and poorly graded gravel
with silt and sand sediments usually display rates of 4 to 8 inches per hour. Poorly graded sand and gravel
sediments typically exhibit infiltration values in excess of 12 inches per hour. Infiltration testing is generally
not required within these sediments because of their free -draining nature.
It is recommended that infiltration facilities constructed on the site be extended into native poorly graded gravel
with sand sediments. Excavation depths of approximately 8.6 to 10.2 feet bgs should be anticipated to expose
these poorly graded gravel with sand sediments. Because of the high soil permeability, ASTM C33 filter sand,
or equivalent, should be incorporated into design of infiltration facilities. An infiltration rate of 8 inches per
hour should be used in design. Actual infiltration rates should be confirmed at the time of construction.
FOUNDATION, SLAB, AND PAVEMENT DISCUSSION AND RECOMMENDATIONS
Various foundation types have been considered for support of the proposed development. Two requirements
must be met in the design of foundations. First, the applied bearing stress must be less than the ultimate bearing
capacity of foundation soils to maintain stability. Second, total and differential settlement must not exceed an
amount that will produce an adverse behavior of the superstructure. Allowable settlement is usually exceeded
before bearing capacity considerations become important; thus, allowable bearing pressure is normally
controlled by settlement considerations.
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Considering subsurface conditions and the proposed construction, it is recommended that the development be
founded upon conventional spread footings and continuous wall footings. Total settlements should not exceed
1 inch if the following design and construction recommendations are observed. Presently, there are 13 lots
proposed for the project site. The following recommendations are not specific to the individual structures, but
rather should be viewed as guidelines for the subdivision — wide development.
Foundation Design Recommendations
Based on data obtained from the site and test results from various laboratory tests performed, MTI recommends
the following guidelines for the net allowable soil bearing capacity:
Soil BearinLy Capacity
Footing Depth
ASTM D1557
Sub rade Com action
Net Allowable
Soil Bearin . Ca' aci
Footings must bear on competent, undisturbed,
1,500 lbs/ft'
native lean clay, silt, or sandy silt soils, or
Not Required for Native
compacted structural fill. Existing plow zones and
Soil
A /3 increase is allowable
organic materials must be completely removed from
for short-term loading,
below foundation elements.' Excavation depths
95% for Structural Fill
Which is defined by seismic
ranging from roughly 1.0 to 1.1 feet bgs should be
events or designed wind
anticipated to expose proper bearing soils.2
speeds.
'It will be required for MTI personnel to verify the bearing soil suitability for each structure at the time of construction.
2Depending on the time of year construction takes dace the subgrade soils may be unstable because of high moisture
contents If unstable conditions are encountered over -excavation and replacement with granular structural fill and/or use
of geotextiles may b� e required.
The following sliding frictional coefficient values should be used: 1) 0.35 for footings bearing on native lean
clay, silt, or sandy silt soils and 2) 0.45 for footings bearing on granular structural fill. A passive lateral earth
pressure of 286 pounds per square foot per foot (psf/ft) should be used for lean clay, silt, or sandy silt soils. For
compacted sandy gravel fill, a passive lateral earth pressure of 496 psf/ft should be used.
Footings should be proportioned to meet either the stated soil bearing capacity or the 2015 IBC minimum
requirements. Total settlement should be limited to approximately 1 inch, and differential settlement should be
limited to approximately '/2 inch. Objectionable soil types encountered at the bottom of footing excavations
should be removed and replaced with structural fill. Excessively loose or soft areas that are encountered in the
footings subgrade will require over -excavation and backfilling with structural fill. To minimize the effects of
slight differential movement that may occur because of variations in the character of supporting soils and
seasonal moisture content, MTI recommends continuous footings be suitably reinforced to make them as rigid
as possible. For frost protection, the bottom of external footings should be 24 inches below finished grade.
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All residences constructed with crawl spaces should be designed in a manner that will inhibit water in the crawl
spaces. MTI recommends that roof drains carry stormwater at least 10 feet away from each residence. Grades
should be at least 5 percent for a distance of 10 feet away from all residences. In addition, rain gutters should
be placed around all sides of residences, and backfill around stem walls should be placed and compacted in a
controlled manner.
Floor, Patio, and Garage Slab -on -Grade
Plow zones, which should be treated as uncontrolled fill, were encountered across of the site. MTI recommends
that these plow zones be excavated to a sufficient depth to expose competent, native soils. MTI personnel must
be present during excavation to identify these materials.
Organic, loose, or obviously compressive materials must be removed prior to placement of concrete floors or
floor -supporting fill. In addition, the remaining subgrade should be treated in accordance with guidelines
presented in the Earthwork section. Areas of excessive yielding should be excavated and backfilled with
structural fill. Fill used to increase the elevation of the floor slab should meet requirements detailed in the
Structural Fill section. Fill materials must be compacted to a minimum 95 percent of the maximum dry density
as determined by ASTM D1557.
A free -draining granular mat (drainage fill course) should be provided below slabs -on -grade. This should be a
minimum of 4 inches in thickness and properly compacted. The mat should consist of a sand and gravel mixture,
complying with Idaho Standards for Public Works Construction (ISPWC) specifications for 3/4 -inch (Type 1)
crushed aggregate. The granular mat should be compacted to no less than 95 percent of the maximum dry
density as determined by ASTM D1557. A moisture -retarder should be placed beneath floor slabs to minimize
potential ground moisture effects on moisture -sensitive floor coverings. The moisture -retarder should be at
least 15 -mil in thickness and have a permeance of less than 0.01 US perms as determined by ASTM E96.
Placement of the moisture -retarder will require special consideration with regard to effects on the slab -on -grade
and should adhere to recommendations outlined in the ACI 302.1R and ASTM E1745 publications. Upon
request, MTI can provide further consultation regarding installation.
Recommended Pavement Sections
MTI has made assumptions for traffic loading variables based on the character of the proposed construction.
The Client shall review and understand these assumptions to make sure they reflect intended use and loading
of pavements both now and in the future. MTI collected a sample of near -surface soils for Resistance Value
(R -value) testing representative of soils to depths of 1.3 to 2.3 feet bgs. This sample, consisting of lean clay
collected from test pit 3, yielded a R -value of less than 5. The R -value was converted to a CBR value of 2 for
design calculations. The following are minimum thickness requirements for assured pavement function.
Depending on site conditions, additional work, e.g. soil preparation, may be required to support construction
equipment. These have been listed within the Soft Subgrade Soils section. Results of the test are graphically
depicted in the Appendix.
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Flexible Pavement Section
The American Association of State Highway and Transportation Officials (AASHTO) design method has been
used to calculate the following pavement section. A calculation sheet provided in the Appendix indicates the
soils constant, traffic loading, traffic projections, and material constants used to calculate the pavement section.
MTI recommends that materials used in the construction of asphaltic concrete pavements meet requirements of
the ISPWC Standard Specification for Highway Construction. Construction of the pavement section should be
in accordance with these specifications and should adhere to guidelines recommended in the section on
Construction Considerations.
AASHTO Flexible Pavement Specifications
Pavement Section Com onenti
Residential Roadway
Asphaltic Concrete
2.5 Inches
Crushed Aggregate Base
4.0 Inches
Structural Subbase
16.0 Inches
Compacted Subgrade
See Pavement Subgrade
Preparation Section
1It will be required for MTI personnel to verify subgrade competency at the time of construction.
Asphaltic Concrete: Asphalt mix design shall meet the requirements of ISPWC, Section 810 Class III plant
mix. Materials shall be placed in accordance with ISPWC Standard Specifications for
Highway Construction.
Aggregate Base: Material complying with ISPWC Standards for Crushed Aggregate Materials.
Structural Subbase: Granular structural fill material complying with the requirements detailed in the
Structural Fill section of this report except that the maximum material diameter is no
more than 2/3 the component thickness. Gradation and suitability requirements shall
be per ISPWC Section 801, Table 1.
Pavement Suberade Preparation
Plow zones, which should be treated as uncontrolled fill, were encountered across of the site. MTI recommends
that these plow zones be excavated to a sufficient depth to expose competent, native soils. MTI personnel must
be present during excavation to identify these materials.
Depending on final site grading it is possible that the native clay soils may be completely removed from beneath
the proposed pavement section. If that is the case, MTI can be contacted to provide alternate pavement section
recommendations.
Common Pavement Section Construction Issues
The subgrade upon which above pavement sections are to be constructed must be properly stripped, inspected,
and proof -rolled. Proof rolling of subgrade soils should be accomplished using a heavy rubber -tired, fully
loaded, tandem -axle dump truck or equivalent.
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Verification of subgrade competence by MTI personnel at the time of construction is required. Fill materials
on the site must demonstrate the indicated compaction prior to placing material in support of the pavement
section. MTI anticipated that pavement areas will be subjected to moderate traffic. Subgrade clays and silts
near and above optimum moisture contents may pump during compaction. Pumping or soft areas must be
removed and replaced with structural fill.
Fill material and aggregates, as well as compacted native subgrade soils, in support of the pavement section
must be compacted to no less than 95 percent of the maximum dry density as determined by ASTM D698 for
flexible pavements and by ASTM D 15 57 for rigid pavements. If a material placed as a pavement section
component cannot be tested by usual compaction testing methods, then compaction of that material must be
approved by observed proof rolling. Minor deflections from proof rolling for flexible pavements are allowable.
Deflections from proof rolling of rigid pavement support courses should not be visually detectable.
CONSTRUCTION CONSIDERATIONS
Recommendations in this report are based upon structural elements of the project being founded on competent,
native lean clay, silt, or sandy silt soils or compacted structural fill. Structural areas should be stripped to an
elevation that exposes these soil types.
Earthwork
Excessively organic soils, deleterious materials, or disturbed soils generally undergo high volume changes when
subjected to loads, which is detrimental to subgrade behavior in the area of pavements, floor slabs, structural
fills, and foundations. Mature trees, brush, and thick grasses with associated root systems were noted at the
time of our investigation. It is recommended that organic or disturbed soils, if encountered, be removed, and
wasted or stockpiled for later use. However, in areas where trees are/were present, deeper excavation depths
should be anticipated. Stripping depths should be adjusted in the field to assure that the entire root zone or
disturbed zone (plow depths) or topsoil are removed prior to placement and compaction of structural fill
materials. Exact removal depths should be determined during grading operations by MTI personnel, and should
be based upon subgrade soil type, composition, and firmness or soil stability. If underground storage tanks,
underground utilities, wells, or septic systems are discovered during construction activities, they must be
decommissioned then removed or abandoned in accordance with governing Federal, State, and local agencies.
Excavations developed as the result of such removal must be backfilled with structural fill materials as defined
in the Structural Fill section.
MTI should oversee subgrade conditions (i.e., moisture content) as well as placement and compaction of new
fill (if required) after native soils are excavated to design grade. Recommendations for structural fill presented
in this report can be used to minimize volume changes and differential settlements that are detrimental to the
behavior of footings, pavements, and floor slabs. Sufficient density tests should be performed to properly
monitor compaction. For structural fill beneath building structures, one in-place density test per lift for every
5,000 square feet is recommended. In parking and driveway areas, this can be decreased to one test per lift for
every 10,000 square feet.
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Dry Weather
If construction is to be conducted during dry seasonal conditions, many problems associated with soft soils may
be avoided. However, some rutting of subgrade soils may be induced by shallow groundwater conditions related
to springtime runoff or irrigation activities during late summer through early fall. Solutions to problems
associated with soft subgrade soils are outlined in the Soft Subgrade Soils section. Problems may also arise
because of lack of moisture in native and fill soils at time of placement. This will require the addition of water
to achieve near -optimum moisture levels. Low -cohesion soils exposed in excavations may become friable,
increasing chances of sloughing or caving. Measures to control excessive dust should be considered as part of
the overall health and safety management plan.
Wet Weather
If construction is to be conducted during wet seasonal conditions (commonly from mid-November through
May), problems associated with soft soils must be considered as part of the construction plan. During this time
of year, fine-grained soils such as silts and clays will become unstable with increased moisture content, and
eventually deform or rut. Additionally, constant low temperatures reduce the possibility of drying soils to near
optimum conditions.
Soft Subgrade Soils
Shallow fine-grained subgrade soils that are high in moisture content should be expected to pump and rut under
construction traffic. During periods of wet weather, construction may become very difficult if not impossible.
The following recommendations and options have been included for dealing with soft subgrade conditions:
• Track -mounted vehicles should be used to strip the subgrade of root matter and other deleterious debris.
Heavy rubber -tired equipment should be prohibited from operating directly on the native subgrade and
areas in which structural fill materials have been placed. Construction traffic should be restricted to
designated roadways that do not cross, or cross on a limited basis, proposed roadway or parking areas.
• Soft areas can be over -excavated and replaced with granular structural fill.
• Construction roadways on soft subgrade soils should consist of a minimum 2 -foot thickness of large
cobbles of 4 to 6 inches in diameter with sufficient sand and fines to fill voids. Construction entrances
should consist of a 6 -inch thickness of clean, 2 -inch minimum, angular drain -rock and must be a
minimum of 10 feet wide and 30 to 50 feet long. During the construction process, top dressing of the
entrance may be required for maintenance.
• Scarification and aeration of subgrade soils can be employed to reduce the moisture content of wet
subgrade soils. After stripping is complete, the exposed subgrade should be ripped or disked to a depth
of 1 t/2 feet and allowed to air dry for 2 to 4 weeks. Further disking should be performed on a weekly
basis to aid the aeration process.
• Alternative soil stabilization methods include use of geotextiles, lime, and cement stabilization. MTI is
available to provide recommendations and guidelines at your request.
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Frozen Subgrade Soils
Prior to placement of structural fill materials or foundation elements, frozen subgrade soils must either be
allowed to thaw or be stripped to depths that expose non -frozen soils and wasted or stockpiled for later use.
Stockpiled materials must be allowed to thaw and return to near -optimal conditions prior to use as structural
fill.
The onsite, shallow lean clay and silt soils are susceptible to frost heave during freezing temperatures. For
exterior flatwork and other structural elements, adequate drainage away from subgrades is critical. Compaction
and use of structural fill will also help to mitigate the potential for frost heave. Complete removal of frost
susceptible soils for the full frost depth, followed by replacement with a non -frost susceptible structural fill, can
also be used to mitigate the potential for frost heave. MTI is available to provide further guidance/assistance
upon request.
Structural Fill
Soils recommended for use as structural fill are those classified as GW, GP, SW, and SP in accordance with the
Unified Soil Classification System (USCS) (ASTM D2487). Use of silty soils (USCS designation of GM, SM,
and ML) as structural fill may be acceptable. However, use of silty soils (GM SM and ML) as structural fill
below footings is prohibited. These materials require very high moisture contents for compaction and require
a long time to dry out if natural moisture contents are too high and may also be susceptible to frost heave under
certain conditions. Therefore, these materials can be quite difficult to work with as moisture content, lift
thickness, and compactive effort becomes difficult to control. If silty soil is used for structural fill, lift
thicknesses should not exceed 6 inches (loose) and fill material moisture must be closely monitored at both the
working elevation and the elevations of materials already placed. Following placement, silty soils must be
protected from degradation resulting from construction traffic or subsequent construction.
Recommended granular structural fill materials, those classified as GW, GP, SW, and SP, should consist of a
6 -inch minus select, clean, granular soil with no more than 50 percent oversize (greater than 3/4 -inch) material
and no more than 12 percent fines (passing No. 200 sieve). These fill materials should be placed in layers not
to exceed 12 inches in loose thickness. Prior to placement of structural fill materials, surfaces must be prepared
as outlined in the Construction Considerations section. Structural fill material should be moisture -conditioned
to achieve optimum moisture content prior to compaction. For structural fill below footings, areas of compacted
backfill must extend outside the perimeter of the footings for a distance equal to the thickness of fill between
the bottom of foundation and underlying soils, or 5 feet, whichever is less. All fill materials must be monitored
during placement and tested to confirm compaction requirements, outlined below, have been achieved.
Each layer of structural fill must be compacted, as outlined below:
Below Structures and Rigid Pavements: A minimum of 95 percent of the maximum dry density as
determined by ASTM D1557.
Below Flexible Pavements: A minimum of 92 percent of the maximum dry density as determined by
ASTM D1557 or 95 percent of the maximum dry density as determined by ASTM D698.
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The ASTM D1557 test method must be used for samples containing up to 40 percent oversize (greater than 3/4 -
inch) particles. If material contains more than 40 percent but less than 50 percent oversize particles, compaction
of fill must be confirmed by proof rolling each lift with a 10 -ton vibratory roller (or equivalent) until the
maximum density has been achieved. Density testing must be performed after each proof rolling pass until the
in-place density test results indicate a drop (or no increase) in the dry density, defined as maximum density or
"break over" point. The number of required passes should be used as the requirements on the remainder of fill
placement. Material should contain sufficient fines to fill void spaces, and must not contain more than 50
percent oversize particles.
Backfill of Walls
Backfill materials must conform to the requirements of structural fill, as defined in this report. For wall heights
greater than 2.5 feet, the maximum material size should not exceed 4 inches in diameter. Placing oversized
material against rigid surfaces interferes with proper compaction, and can induce excessive point loads on walls.
Backfill shall not commence until the wall has gained sufficient strength to resist placement and compaction
forces. Further, retaining walls above 2.5 feet in height shall be backfilled in a manner that will limit the
potential for damage from compaction methods and/or equipment. It is recommended that only small hand -
operated compaction equipment be used for compaction of backfill within a horizontal distance equal to the
height of the wall, measured from the back face of the wall.
Backfill should be compacted in accordance with the specifications for structural fill, except in those areas
where it is determined that future settlement is not a concern, such as planter areas. In nonstructural areas,
backfill must be compacted to a firm and unyielding condition.
Excavations
Shallow excavations that do not exceed 4 feet in depth may be constructed with side slopes approaching vertical.
Below this depth, it is recommended that slopes be constructed in accordance with Occupational Safety and
Health Administration (OSHA) regulations, Section 1926, Subpart P. Based on these regulations, on-site soils
are classified as type "C" soil, and as such, excavations within these soils should be constructed at a maximum
slope of 1'/2 feet horizontal to 1 foot vertical (1%2:1) for excavations up to 20 feet in height. Excavations in
excess of 20 feet will require additional analysis. Note that these slope angles are considered stable for short-
term conditions only, and will not be stable for long-term conditions.
During the subsurface exploration, test pit sidewalls generally exhibited little indication of collapse; however,
sloughing of native granular sediments from test pit sidewalls was observed. For deep excavations, native
granular sediments cannot be expected to remain in position. These materials are prone to failure and may
collapse, thereby undermining upper soil layers. This is especially true when excavations approach depths near
the water table. Care must be taken to ensure that excavations are properly backfilled in accordance with
procedures outlined in this report.
Shallow soil cementation (caliche) was observed throughout much of the site and may cause difficulties during
foundation development and utility placement. Cemented soils should be anticipated throughout the site at
depths of 2.0 to 6.8 feet bgs.
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Groundwater Control
Groundwater was encountered not during the investigation and is anticipated to be below the depth of most
construction. Special precautions may be required for control of surface runoff and subsurface seepage. It is
recommended that runoff be directed away from open excavations. Clay and silt soils may become soft and
pump if subjected to excessive traffic during time of surface runoff. Ponded water in construction areas should
be drained through methods such as trenching, sloping, crowning grades, nightly smooth drum rolling, or
installing a French drain system. Additionally, temporary or permanent driveway sections should be
constructed if extended wet weather is forecasted.
GENERAL COMMENTS
Based on the subsurface conditions encountered during this investigation and available information regarding
the proposed development, the site is adequate for the planned construction. When plans and specifications are
complete and if significant changes are made in the character or location of the proposed structure, consultation
with MTI must be arranged as supplementary recommendations may be required. Suitability of subgrade soils
and compaction of structural fill materials must be verified by MTI personnel prior to placement of structural
elements. Additionally, monitoring and testing should be performed to verify that suitable materials are used
for structural fill and that proper placement and compaction techniques are utilized.
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REFERENCES
American Concrete Institute (ACI) (2015). Guide for Concrete Floor and Slab Construction: ACI 302.1R. Farmington Hills, MI: ACI.
American Society of Civil Engineers (ASCE) (2013). Minimum Design Loads for Buildings and Other Structures: ASCE/SEI 7-10.
Reston, VA: ASCE.
American Society for Testing and Materials (ASTM) (2013). Standard Test Method for Materials Finer than 75-µm (No. 200) Sieve
in Mineral Aggregates by Washing: ASTM C117. West Conshohocken, PA: ASTM.
American Society for Testing and Materials (ASTM) (2014). Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates:
ASTM C136. West Conshohocken, PA: ASTM.
American Society for Testing and Materials (ASTM) (2012). Standard Test Methods for Laboratory Compaction Characteristics of
Soil Using Standard Effort: ASTM D698. West Conshohocken, PA: ASTM.
American Society for Testing and Materials (ASTM) (2012). Standard Test Methods for Laboratory Compaction Characteristics of
Soil Using Modified Effort: ASTM D1557. West Conshohocken, PA: ASTM.
American Society for Testing and Materials (ASTM) (2013). Standard Test Methods for Resistance Value (R -Value) and Expansion
Pressure of Compacted Soils: ASTM D2844, West Conshohocken, PA: ASTM.
American Society for Testing and Materials (ASTM) (2011). Standard Practice for Classification of Soils for Engineering Purposes
(Unified Soil Classification System): ASTM D2487. West Conshohocken, PA: ASTM.
American Society for Testing and Materials (ASTM) (2010). Standard Test Methods for Liquid Limit, Plastic Limit, and Plasticity
Index of Soils: ASTM D4318. West Conshohocken, PA: ASTM.
American Society for Testing and Materials (ASTM) (2011). Standard Specification for Plastic Water Vapor Retarders Used in
Contact with Soil or Granular Fill Under Concrete Slabs: ASTM E1745. West Conshohocken, PA: ASTM.
American Society of State Highway and Transportation Officials (AASHTO) (1993). AASHTO Guide for Design of Pavement
Structures 1993. Washington D.C.: AASHTO.
Desert Research Institute. Western Regional Climate Center. [Online] Available: <http://www.wrcc.dri.edu/> (2018).
International Building Code Council (2015). International Building Code, 2015. Country Club Hills, IL: Author.
Local Highway Technical Assistance Council (LHTAC) (2017). Idaho Standards for Public Works Construction 2017. Boise, ID:
Author.
Othberg, K. L. and Stanford, L. A., Idaho Geologic Society (1992). Geologic Map of the Boise Valley and Adjoining Area, Western
Snake River Plain, Idaho. (scale 1:100,000). Boise, ID: Joslyn and Morris.
U.S. Department of Labor, Occupational Safety and Health Administration. CFR 29 Part1926, Subpart P: Safety and Health
Regulations for Construction Excavations (1986). [Online] Available: <www.osha.gov> (2018).
U.S. Geological Survey (2018). National Water Information System: Web Interface. [Online] Available:
<http://waterdata.usgs.gov/nwis> (2018).
U.S. Geological Survey. (2011). U.S. Seismic Design Maps: Web Interface. [Online] Available:
<https://earthquake.usgs.gov/designmaps/us/application.php> (2018).
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APPENDICES
ACRONYM LIST
AASHTO: American Association of State Highway and Transportation Officials
ACI American Concrete Institute
ASCE American Society of Civil Engineers
ASTM: American Society for Testing and Materials
bgs: below ground surface
CBR: California Bearing Ratio
D: natural dry unit weight, pcf
ESAL Equivalent Single Axle Load
GS: grab sample
IBC: International Building Code
LL: Liquid Limit
M: water content
MSL: mean sea level
N: Standard "N" penetration: blows per foot, Standard Penetration Test
NP: nonplastic
OSHA Occupational Safety and Health Administration
PCCP: Portland Cement Concrete Pavement
PERM: vapor permeability
PI: Plasticity Index
PID: photoionization detector
PVC: polyvinyl chloride
QC: cone penetrometer value, unconfined compressive strength, psi
Qp: Penetrometer value, unconfined compressive strength, tsf
Qu: Unconfined compressive strength, tsf
RMR Rock Mass Rating
RQD Rock Quality Designation
R -Value Resistance Value
SPT: Standard Penetration Test (140:pound hammer falling 30 in. on a 2:in. split spoon)
USCS: Unified Soil Classification System
USDA: United States Department of Agriculture
UST: underground storage tank
V: vane value, ultimate shearing strength, tsf
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GEOTECHNICAL GENERAL NOTES
Moisture Content
RELATIVE DENSITY AND CONSISTENCY CLASSIFICATION
Field Test
Coarse -Grained Soils
SPT Blow Counts N Fine -Grained Soils
SPT Blow Counts N
Very Loose:
< 4 Very Soft:
< 2
Loose:
4-10 Soft:
2-4
Medium Dense:
10-30 Medium Stiff:
4-8
Dense:
30-50 Stiff.
8-15
Very Dense:
>50 Very Stiff.
15-30
CH Fat clays; high -plasticity, inorganic clays
Hard:
>30
Moisture Content
Description
Field Test
Dry
Absence of moisture, dusty, dry to touch
Moist
Damp but not visible moisture
Wet
Visible free water, usually soil is below
water table
PARTICLE SIZE
Boulders: >12 in. Coarse -Grained Sand: 5 to 0.6 mm Silts: 0.075 to 0.005 mm
Cobbles: 12 to 3 in. Medium -Grained Sand: 0.6 to 0.2 mm Clays: <0.005 mm
Gravel: 3 in. to 5 mm Fine -Grained Sand: 0.2 to 0.075 mm
UNIFIED SOIL CLASSIFICATION SYSTEM
Cementation
Description
Field Test
Weakly
Crumbles or breaks with handling or
GP Poorly -graded gravels; gravel/sand mixtures with little or no fines
slight finger pressure
Moderately
Crumbles or beaks with considerable
SW Well -graded sands; gravelly sands with little or no fines
finger pressure
Strongly
Will not crumble or break with finger
Fine Grained
Soils >50%
passes No.200
sieve
pressure
PARTICLE SIZE
Boulders: >12 in. Coarse -Grained Sand: 5 to 0.6 mm Silts: 0.075 to 0.005 mm
Cobbles: 12 to 3 in. Medium -Grained Sand: 0.6 to 0.2 mm Clays: <0.005 mm
Gravel: 3 in. to 5 mm Fine -Grained Sand: 0.2 to 0.075 mm
UNIFIED SOIL CLASSIFICATION SYSTEM
Major Divisions
Symbol . Soil, Descriptions
Coarse -Grained
Soils
<50%
passes No.200
sieve
Gravel & Gravelly
Soils
<50%
coarse fraction
passes No.4 sieve
GW Well -graded gravels; gravel/sand mixtures with little or no fines
GP Poorly -graded gravels; gravel/sand mixtures with little or no fines
GM Silty gravels; poorly -graded gravel/sand/silt mixtures
GC Clayey gravels; poorly -graded gravel/sand/clay mixtures
Sand & Sandy
Soils
>50%
coarse fraction
passes No.4 sieve
SW Well -graded sands; gravelly sands with little or no fines
SP Poorly -graded sands; gravelly sands with little or no fines
SM Silty sands; poorly -graded sand/gravel/silt mixtures
SC Clayey sands; poorly -graded sand/gravel/clay mixtures
Fine Grained
Soils >50%
passes No.200
sieve
Silts & Clays
LL < 50
ML Inorganic silts; sandy, gravelly or clayey silts
CL Lean clays; inorganic, gravelly, sandy, or silty, low to medium -plasticity clays
OL Organic, low -plasticity clays and silts
Silts & Clays
LL > 50
MH Inorganic, elastic silts; sandy, gravelly or clayey elastic silts
CH Fat clays; high -plasticity, inorganic clays
OH Organic, medium to high -plasticity clays and silts
Highly Organic Soils
PT I Peat, humus, hydric soils with high organic content
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GEOTECHNICAL INVESTIGATION TEST PIT LOG
Test Pit Log #: TP -1 Date Advanced: 7 Jan 2018 Logged by: Maren Tanberg, E.I.T., G.I.T.
Excavated by: Struckman's Backhoe Service Location: See Site Map Plates
Latitude: 43.641319 Longitude: -116.377389
Depth to Water Table: Not Encountered Total Depth: 16.1 Feet bgs
Depth
Field Description and USCS Soil and
Sample
Sample Depth
QP
Lab
Feet bgs)
Sediment Classification
T e
eet b s
Test ID
Lean Clay (CL): Brown, moist, stiff to very
0.0-2.0
stiff.
--Organic materials and plow zone noted to
1.5-3.75
LI feet bgs.
Sandy Silt (ML): Brown, dry to slightly
moist, very stiff to hard, with fine to medium -
2.0 -5.5
grained sand.
--Weak to moderate calcium carbonate
cementation noted from 3.3 to 5.5 feet bgs.
Poorly Graded Gravel with Silt and Sand
5.5-8.6
(GP -GM): Brown, dry, dense to very dense,
with fine to coarse-grained sand, fine to
coarse gravel, and 4 -inch -minus cobbles.
Poorly Graded Gravel with Sand (GP): Light
brown, dry, medium dense to dense, with fine
8.6-16.1
to coarse-grained sand fine to coarse gravel,
11-inch-minzrs cobbles.
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als
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GEOTECHNICAL INVESTIGATION TEST PIT LOG
23 January 2019
Page # 22 of 27
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Special Inspections
Test Pit Log #: TP -2 Date Advanced: 7 Jan 2018 Logged by: Maren Tanberg, E.I.T., G.I.T.
Excavated by: Struckman's Backhoe Service Location: See Site Map Plates
Latitude: 43.641673 Longitude: -116.377396
Depth to Water Table: Not Encountered Total Depth: 12.3 Feet bgs
Depth
Field Description and USCS Soil and
Sample
Sample Depth
Qp
Lab
'(Feet bgs)
Sediment Classification
Type(Feet
bgs)
Test ID
Lean Clay (CL): Brown, moist, stiff to very
0.0-1.4
stiff.
--Organic materials and plow zone noted to
2.0-2.5
1.0 foot bgs.
1.4-2.0
Silt (ML): Dark brown, slightly moist, very
2.5-4.0
stiff, with fine- rained sand.
Sandy Silt (ML): Light brown, dry to slightly
moist, very stiff to hard, with fine to medium -
2.0 -5.3
grained sand.
--Weak to moderate calcium carbonate
cementation noted om 2.0 to 3.8 eet bgs.
Poorly Graded Gravel with Silt and Sand
(GP -GM): Brown, dry to slightly moist, very
5.3-9.1
dense, with fine to coarse-grained sand, fine
to coarse gravel, and 5 -inch -minus cobbles.
Poorly Graded Gravel with Sand (GP): Light
brown, dry, medium dense to dense, with fine
9.1-12.3
to coarse-grained sand, fine to coarse gravel,
and 8 -inch -minus cobbles.
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GEOTECHNICAL INVESTIGATION TEST PIT LOG
Test Pit Log #: TP -3 Date Advanced: 7 Jan 2018 Logged by: Maren Tanberg, E.I.T., G.I.T.
Excavated by: Struckman's Backhoe Service Location: See Site Map Plates
Latitude: 43.641773 Longitude: -116.377840
Depth to Water Table: Not Encountered Total Depth: 15.2 Feet bgs
Depth
Field Description and USCS Soil and
Sample
Sample Depth
Qp
Lab
{Feet bgs)
Sediment Classification
Type
(Feet bgs)
Test ID
Lean Clay (CL): Brown to dark brown, moist,
medium stiff to stiff.
0.0-2.3
--Organic materials and plow zone noted to
Bulk
1.3-2.3
1.0-1.5
A
1.0 foot bgs.
R -value
--Minor organic materials noted to 2.0 feet
bgs.
Sandy Silt (ML): Brown to light brown,
slightly moist to moist, very stiff to hard, with
fine to medium -grained sand.
2.3-6.8
--Weak calcium carbonate cementation noted
from 2.5 to 5.0 feet bgs.
--Moderate to strong calcium carbonate
cementation noted from 5.0 to 6.8 feet bgs.
Silty Sand (SM): Brown to red brown, dry to
6.8-8.5
slightly moist, dense to very dense, with fine
to coarse-grained sand.
Poorly Graded Sand (SP): Light brown, dry,
8.5-10.2
medium dense, with fine to coarse-grained
sand.
Poorly Graded Gravel with Sand (GP): Light
brown, dry, medium dense to dense, with fine
10.2-15.2
to coarse-grained sand, fine to coarse gravel,
and 12 -inch -minus cobbles.
Lab Test ID M LL PI Sieve Anal sis M passin0
#10 #40 #100 #200
A 26.7 H39 20 100 100 99 98 95.5
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AASHTO PAVEMENT THICKNESS DESIGN PROCEDURES
Pavement Section Design Location: Caldera Canyon Subdivision, Emergency Vehicle Access
Average Daily Traffic Count:
Design Life:
Percent of Traffic in Design Lane:
Terminal Seviceability Index (Pt):
Level of Reliability:
Subgrade CBR Value:
Passenger Cars:
Buses:
Panel & Pickup Trucks:
2 -Axle, 6 -Tire Trucks:
Emergency Vehicles:
Dump Trucks:
Tractor Semi Trailer Trucks:
Double Trailer Trucks
Heavy Tractor Trailer Combo Trucks:
Average Daily Traffic in Design Lane:
200
All Lanes & Both Directions
Structural
20
Years
Inches
Coefficient
50%
Asphaltic Concrete:
2.50
0.42
2.5
Asphalt -Treated Base:
0.00
0.25
95
Cement -Treated Base:
0.00
0.17
2
Crushed Aggregate Base:
Subgrade Mr:
3,000
Calculation of Design -18
kip ESALs
16.00
Daily
Gro«th
Load
Design
Traffic
Rate
Factors
ESALs
58
2.0%
0.0008
412
1
2.0%
0.6806
6,036
40
2.0%
0.0122
4,328
0
2.0%
0.1890
0
1.0
2.0%
4.4800
39,731
0
2.0%
3.6300
0
0
2.0%
2.3719
0
0
2.0%
2.3187
0
0
2.0%
2.9760
0
100
Total Design Life 18 -kip ESALs: 50,506
Actual Log (ESALs): 4.703
Trial SN: 3.21
Trial Log (ESALs): 4.705
Pavement Section Design SN: 3.21
Design
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Inspection
Depth
Structural
Drainage
Inches
Coefficient
Coefficient
Asphaltic Concrete:
2.50
0.42
n/a
Asphalt -Treated Base:
0.00
0.25
n/a
Cement -Treated Base:
0.00
0.17
n/a
Crushed Aggregate Base:
4.00
0.14
1.0
Subbase:
16.00
0.10
1.0
Special Aggregate Subgrade:
0.00
0.09
0.9
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R -VALUE LABORATORY TEST DATA
Source and Description:
TP -3: 1.3'-2.3', Lean Clay
Date Obtained:
7 January 2019
Sample ID:
19-7008
Sampling and
Preparation:
ASTM D75:
Moisture Content (%)
AASHTO T2:
X
ASTM
D421:
Expansion Pressure (psi)
AASHTO
T87:
X
Test Standard:
ASTM
D2844:
NA
AASHTO
T190:
NA
Idaho T8:
X
NA
Sample
A
B
C
Dry Density (lb/ft3)
NA
NA
NA
Moisture Content (%)
NA
NA
NA
Expansion Pressure (psi)
NA
NA
NA
Exudation Pressure (psi) I
NA
NA
NA
R -Value I
NA
NA
NA
R -Value @ 200 psi Exudation Pressure = Less than 5**
** ASTM D2844 Note 2: Occasionally, material from very plastic clay -test specimens will extrude from under
the mold and around the follower ram during the loading operation. If this occurs when the 800 -psi point is
reached and fewer than five lights are lighted, the soil should be reported as less than 5 R -value.
R -Value @ Exudation Pressure
I
90.0
88.0
86.0
84.0
Wt82.0
80.0
400 350 300 250 200 150 100 50
Exudation Pressure (psi)
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Pressure Irrigation Report
Caldera Canyon Subdivision
Meridian, Idaho
Prepared for:
Caldera Canyon Subdivision HOA
November 2019
Project No: 17-70
Prepared by:
Derritt Kerner, P.E.
AM
ROCK SOLID
CIVIL
Civil Engineering and Land Development Consulting
208.342.3277 270 N. 271h Street Boise, ID 83702 www.rocksolidcivil.com
Pressure Irrigation Report
Caldera Canyon Subdivision
Table of Contents
I. PROJECT INFORMATION......................................................................................1
II. OVERVIEW..........................................................................................................1
III. GRAVITY IRRIGATION WATER SUPPLY..................................................................1
IV. PRESSURE IRRIGATION WATER DEMAND.............................................................2
V. MINIMUM FLOW RATE REQUIREMENTS (Amax)..................................................3
VI. DIVERSION STRUCTURE.......................................................................................3
VII. FILTRATION.....................................................................................................3
VIII. WET WELL.......................................................................................................3
IX. PUMP STATION GRAVITY OVERFLOW..................................................................4
X. PUMPS................................................................................................................4
XI. VARIABLE FREQUENCY DRIVES (VFD)...................................................................4
XII. PUMP CONTROL SYSTEM.................................................................................4
Xlil. HARMONICS....................................................................................................5
XIV. PUMP HOUSE/ENCLOSURE..............................................................................5
XV. PRESSURE DISTRIBUTION SYSTEM....................................................................5
XVI. INDIVIDUAL ZONE DESIGN...............................................................................6
XVII. HYDRAULIC ANALYSIS......................................................................................6
XVIII. OPERATIONS AND MAINTENANCE MANUAL....................................................7
FIGURE1: VICINITY MAP.............................................................................................8
APPENDIX A: HYDRAULIC ANALYSIS EPANET2...........................................................10
i
Pressure Irrigation Report
Caldera Canyon Subdivision
The following Pressure Irrigation Report is presented for Caldera Canyon
Subdivision, located in the SE % of the NE % of Section 31, T.4N., R.1E., B.M., City of
Meridian, Ada County, Idaho.
I. PROJECT INFORMATION
A. NAME OF PROJECT: Caldera Canyon Subdivision
B. LOCATION OF PROJECT: The project location is at 1294 E. Leigh Field Dr. just
west of N. Locust Grove Rd. in Meridian, ID. (See Figure I: Vicinity Map)
LEGAL DESCRIPTION OF PROJECT: Located in the SE % of the NE % of Section 31, T.4N.,
R.1E., B.M., City of Meridian, Ada County, Idaho.
C. OWNER'S CONTACT INFORMATION: Randy Sohn, 1294 E. Leigh Field Dr.,
Meridian, Idaho 83686
D. ENGINNER
1. ENGINEERING FIRM: Rock Solid Civil, LLC
2. ENGINEER'S CONTACT INFORMATION: Address is 270 N. 27th Street,
Boise, Idaho 83702. Telephone number is 208-342-3277.
3. ENGINEER'S LICENSE NUMBER: Derritt Kerner, P.E., Idaho Registered
Professional Engineer License #17887.
E. AREA OF PROJECT
1. NUMBER OF LOTS: 3 Common Lots, 16 Residential Building Lots
2. AREA OF SITE: 2.83 acres
3. LANDSCAPE AREA: 0.92 acres
II. OVERVIEW
This narrative accompanies the hydraulic analysis of the distribution pipe
network and construction plans. The design is a private system that is supplied by a user
ditch and will be owned and maintained by the Caldera Canyon Subdivision HOA.
The project site is located at 1294 E. Leigh Field Drive in Meridian, Idaho. The
proposed development is currently located in the City of Meridian and is zoned R8.
Construction will consist of 1 existing residence lot, 15 new buildable lots and 3 common
lots. Access is provided via E. Leigh Field Dr. The development totals approximately 2.83
acres.
There exists a user ditch that flows throughout the property and supplies the site
with irrigation water. Irrigation Water Shares exist through the Settlers Irrigation
District. The project site's pump station will be located at the north end of the property.
III. GRAVITY IRRIGATION WATER SUPPLY
The development is eligible for 2.18 Miner's inches through the Settler's
Irrigation District. Settler's Irrigation District diverts irrigation water via the Nourse
Lateral. There is an irrigation water schedule in place for this development and this
1
Pressure Irrigation Report
Caldera Canyon Subdivision
irrigation design takes into account the eligible irrigation water and availability and can
run all lots simultaneously for 48 hours every 12 days per month in relation to the water
schedule. If incoming flow were to decrease or irrigation water demand increases, the
HOA must establish a rotation schedule to ensure the pump will run without shutoff due
to lack of water.
For the purposes of determining the amount of available water to the project
site, we set the current water right of 2.18 Miner's inches of continuous flow or (2.18
miner's inches/day = 0.044 cfs = 19.57 gpm). Historically, the project site received a
large head of water for a 24-hour period every 12 days. This large head of water totals
as much as 41.34 miners inches (372 gpm). Water flood irrigated the pasture by flowing
to the northwest corner of the property where it entered a piped drain which flows
southbound as part of the improvements within Quenzer Commons. A large head of
water delivered on a rotation is not ideal for developed subdivisions. Some day when
the surrounding areas develop it is possible that a water users rotation schedule will
change in that a continuous low flow of water can be expected to supply the subdivision
all the time. Until that time arrives, a large capacity pump is specified so that all lots can
irrigate simultaneously during a 48-hour irrigation window every 12 -days. The neighbor
to the east that historically received water for a 24-hour period will now irrigate for a
48-hour period and the Caldera Canyon pump station will receive tailwater runoff for
the same 48-hour period. Once the large head of water is released from the supply
lateral, it is anticipated that there will be a few hours of lag time until the tailwaters
reach the Caldera Canyon pump station and irrigation of the subdivision can commence.
During the off-season a back-flow prevention device will allow the use of domestic city
water to supply the PI system. It is important to note that there are no users
downstream of the Caldera Canyon irrigation drain piping. Therefore, Caldera Canyon
can realistically use all the water it receives with no consequence, regardless of how
little or large the flow is.
IV. PRESSURE IRRIGATION WATER DEMAND
Based on the estimated total irrigation/landscape area of 0.92 acres, and using a
conservative lawn application rate of 0.40 inches/day:
0.92 acres x 0.40 in/day = 0.369 acre-inches/day = 0.031 acre-feet/day = 0.015 cfs = 6.9
gpm. As demonstrated, the supply exceeds the demand from a water right perspective.
In reality, Caldera Canyon will receive a large head of water for a 24-hour period every
12 days. In order to capitalize on this large non -continuous water delivery, we design a
pump station that can irrigate the entire subdivision at once (all lots simultaneously). In
order to achieve this, we set a flow demand of 10 gpm for each lot, which equates to a
total flow demand of 160 gpm for all 16 lots. This was the design parameter for our
pump station design.
2
Pressure Irrigation Report
Caldera Canyon Subdivision
V. MINIMUM FLOW RATE REQUIREMENTS (Amax)
As mentioned above, the current water users rotation schedule will deliver a
large water supply of 372 gpm which is more than the 160 gpm design capacity of the
Caldera Canyon pump station. A conservative PI system design should be able to
provide a minimum of 15 gpm at 45 psi to the entire pressure irrigation system. A
hydraulic analysis will show that the designed PI system is capable of supplying 10 gpm
to all lots simultaneously while maintaining 50 psi to the entire system. The expected
flow demand on the system at any one time is expected to be 160 gpm.
VI. DIVERSION STRUCTURE
Irrigation water will be diverted from the tailwater supply ditch directly to the
wet well via a Clemons Clearwater Self -Cleaning Suction Screen Model CW200 or
equivalent. The Clemons screen will be set low within a deep in-line gravity irrigation
box so it remains submerged. Gravity flow irrigation pipe shall be Class 125 PVC SDR -
32.5 or approved equivalent (per ISPWC Section 901) with watertight connections.
VII. FILTRATION
A Clemons Clearwater Self -Cleaning Suction Screen Model CW200 or equivalent
will be installed in the intake box. This Clemons model demands 20 gpm to operate the
self-cleaning screen. Directly after the Clemons filter, a 4 -inch PVC pipe adapted to a 6 -
inch PVC pipe will supply water to the 48 -inch diameter wet well. Debris no smaller than
1/16" shall enter the wet well. Screens shall be continuously washed with water sprayed
through a nozzle onto the screen surface from a pressure line on the discharge side of
the pump. Debris not allowed into the wet well will be kept in the intake box or flushed
downstream. The heavy solids will settle out into the sump and the lighter debris will
float to the surface. Both the heavier debris in the sump and the lighter floating debris
can be cleaned out manually from the intake box's lid as needed. It is not anticipated
that cleaning will be required often. Filters with 30 mesh equivalent screens shall be
installed on the discharge side of the pumps. Screens shall be easily removed for
maintenance and service. Filters shall have isolation valves to permit maintenance.
Control panel shall have settings for manual and automatic flushing.
VIII. WET WELL
The wet well shall be 48 -inches in diameter and be 12 -feet deep. Water depths
will fluctuate between 8 and 10 feet. The construction area shall be mechanically
compacted to 95% of a standard Proctor. All open bottom wet wells shall be placed on
pre -cast concrete base rings over 8 inches of W crushed aggregate base. Submersible
pumps shall maintain 2 feet separation from well floor. All strap or clamp attachments
shall be stainless steel. Wet well will have a 60 -inch diameter concrete lid to mount the
pump station skid.
Pressure Irrigation Report
Caldera Canyon Subdivision
IX. PUMP STATION GRAVITY OVERFLOW
The system will not include a gravity overflow out of the wet well. The water
level in the wet well will equalize with the water level in the supply lateral/drain. The lid
of the wet well is set just above the highwater line of the supply lateral. The pumps will
shut off if water levels drop too low. When the pumps are not in use, excess supply
water in the supply lateral will continue to flow downstream.
X. PUMPS
Submersible turbine pumps may be used where adequate submersion is allowed
along with a slotted pump protection sleeve. Vertical turbine pumps shall be used where
the elevation of the pump is above the surface elevation of the water being pumped.
This small system will utilize a single submersible turbine pump. Replacement pumps
are readily available to purchase and install within a couple days. System is capable of
delivering low demand flows, accomplished using a variable frequency drive (VFD).
Pump performance shall be rated for a maximum flow of 180 gpm at a TDH = 120 feet.
20 gpm is allocated to operate the Clemons self cleaning screen and the remaining 160
gpm is needed to supply the distribution system. The discharge side shall include, but
not limited to, the following: an air relief, silent check valve rated for 150 psi upstream
of the manifold, VAF filter, gear -operated butterfly valve, 1.5 -inch Polyethylene water
supply line to Clemons filter with Amiad Super Filter and ball valve. All equipment shall
be mounted to a powder -coated metal skid.
XI. VARIABLE FREQUENCY DRIVES (VFD)
Pumps shall be controlled by their own variable frequency drive (VFD) set to
operate the system at constant pressure. A stainless steel pressure transducer shall
continually monitor system pressure, and transmit a signal to the VFD which will react
according to the pre-programmed criteria. The VFDs shall be sized to meet the full load
amps (FLA) required by the pump motor as stated on the nameplate. Pump contractor
to provide shop drawings of pump configuration and plumbing for inclusion in the
record drawings.
XII. PUMP CONTROL SYSTEM
A UL -listed control panel shall include variable frequency drives (VFD) and
programmable logic controllers (PLC). The PLC shall include a digital operator interface.
The VFD pump control panel shall be manufactured and listed by a UL508 Panel Shop.
The panel shall be UL labeled as an "Enclosed Industrial Control Panel" and be dust free,
water and air tight.
If the pump station is equipped with multiple pumps, the pump control system
shall automatically alternate VFD control between the lead and lag pumps, and equalize
usage of the pumps in the system. Initial start-up and calibration shall be performed by
SH
Pressure Irrigation Report
Caldera Canyon Subdivision
a certified technician, trained in all aspects of pump system service, including VFD/PLC
control system. The system shall be pressure tested to 1.5 times operating pressure.
The pump control panel will be constructed to NEMA 311 or better standards and will
include the following features: lightening and surge arrestors; low/high voltage
protection; low level pump shut-off with manual re -set; soft start/stop feature; phase
failure and phase reversal protection; HOA switch; and motor rated circuit breakers with
overload protection. The electrical system should also include a 110 V, 30 -amp
convenience outlet and necessary transformer. The control panel will include a digital
sprinkler irrigation clock to control the solenoid -operated valve for timed cleaning of the
Clemons filter screen.
XIII. HARMONICS
The UL listed VFD/PLC control panel shall meet or exceed IEEE -519 standards. A
letter from Idaho Power stating this requirement has been met will be provided to the
Engineer and HOA.
XIV. PUMP HOUSE/ENCLOSURE
The VFDs and controls shall be mounted in a UL Type 311 enclosure for outdoor
installation. Pump enclosure will be located on a buildable lot within an irrigation
easement. Building and Electrical permits are required. The enclosure shall be of
adequate size to allow for operations, maintenance and repair on equipment within the
enclosure. The roof of the enclosure shall be easily displaced and replaced by one
person, for the purpose of servicing the pump station. The enclosure shall include a
thermostat -controlled exhaust ventilation fan(s) for proper operation of the pump
controls. Special consideration shall be made for heat generated by variable frequency
drives, to prevent high ambient temperatures and/or causing temperature faults or
warnings. The cooling system shall not allow dust and/or dirt inside the pump control
panel. The building shall be equipped with adequate lighting and outlets. The enclosure
shall be locking and be keyed for the HOA. The concrete slab floor shall be sloped to a
drain, and include a fire extinguisher. The ground around the pump enclosure shall be
landscaped or finished with four inches thickness of pea gravel laid over a layer of fabric
to prevent weed growth.
XV. PRESSURE DISTRIBUTION SYSTEM
The project shall be provided with irrigation water with a minimum pressure of
45 psi under design operation conditions with 1 -inch or 1.5 -inch diameter services (per
ISPWC Section 903). All pressure service pipe shall be Polyethylene (PE), Class 160 PSI
conforming to AWWA C-901. All pressure distribution pipe shall be polyvinyl chloride
(PVC), ASTM D2241 Class 200, SDR 21 with gasketed push on joints.
5
Pressure Irrigation Report
Caldera Canyon Subdivision
Pipe shall be placed a minimum of 30 inches deep, except in the right-of-way
where it shall have 36 inches of cover from finished grade. The maximum cover in all
cases shall be 48 inches from finished grade. Trenches shall be water settled or
compacted. Type I bedding material per ISPWC section 305 shall be used in PI trenches
across roadways. Direct tapping of main is not allowed; tees or saddles required. All
irrigation mainlines shall be marked with warning tape as per ISPWC. The tape shall be
buried 6 inches below the surface to 18 inches above the top of the pipe.
Thrust blocks or joint restraints shall be installed where unequal forces exist.
Thrust blocks shall be installed per SD -403 of the ISPWC. All irrigation risers and faucets
shall be identified with durable tags carrying the warning "Danger -Unsafe Water" or
"Non -Potable Water" or equivalent. No irrigation system shall be cross connected in any
manner to any public water system unless the provisions for cross connection
protection are per Meridian City code.
Ten feet of horizontal separation shall be maintained between water lines and
non -potable water lines. "Lines" refers to both mains and services. At any location
where pressure irrigation line and water line cross, the water pipe shall be centered so
that both joints are located as far as possible from the crossing. A vertical separation
distance of 18" shall be maintained per DEQ drinking water standards.
Pipe will be sloped to drain to the locations shown on the plans. Drain plugs and
drain boxes to winterize the system are identified on the plan set, and on the site by a
sign identifying the drain.
Air and vacuum valves are required at all high points of the irrigation distribution
piping and on all dead end lines. Valves shall be in accordance with ANSI/AWWA C 512.
Air and vacuum valve to be Waterman Model CR -101, or equivalent.
All irrigation and drain boxes will be covered with expanded galvanized steel or
aluminum grating or approved equivalent. All covers shall be securely fastened to the
tops of concrete walls.
XVI. INDIVIDUAL ZONE DESIGN
Service will be Polyethylene (PE), 160 PSI, 1 -inch or 1.5 -inch diameter only per
ISPWC SD -902. Each individual zone should be designed for a 10 gpm flow. Low flow
sprinklers and drip systems are anticipated. Property owners or their contractors shall
verify system pressure at each location for the purpose of verifying water demand
relative to system design.
XVII. HYDRAULIC ANALYSIS
The piping network was modeled using EPANET2 software, developed by EPA for
network systems. To solve the flow continuity and headloss equations (hydraulic
balancing) the network requires an iterative technique to solve the nonlinear equations,
and EPANET2 employs the "Gradient Algorithm" for this purpose. Friction headloss was
computed using Hazen -Williams formula with a conservative roughness coefficient
C�
Pressure Irrigation Report
Caldera Canyon Subdivision
C=145 for PVC. To account for minor head losses in PVC fittings and valves, an
appropriate minor loss coefficient was given to each length of distribution pipe.
The expected flow demand of the system is 160 gpm. The system is designed to
provide water for 48 hours every 12 days. Main line pipes will be 4 -inch diameter. The
system will maintain, at all times, a system pressure not greater than 80 psi and not less
than 45 psi at any point in the system.
Recall that the Clemons self cleaning screen demands 20 gpm from the pump for
operation, therefore a pump capable of 180 gpm is needed to supply the self cleaning
screen with 20 gpm and supply the distribution system with 160 gpm while combating
120 of total dynamic head. The hydraulic analysis demonstrates a pump allocating 160
gpm at a TDH = 120 feet is capable of providing 160 gpm at 50 psi to the entire system.
See Appendix A — EPANET2 Hydraulic Analysis. This exceeds our conservative standard
of 15 gpm at 45 psi (minimum).
The VFD will further maintain constant pressure at variable delivery rates for
low, average, and maximum flow conditions.
XVIII. OPERATIONS AND MAINTENANCE MANUAL
Performance specifications are outlined on the construction plans. The
contractor is responsible for providing a complete as -built package for review and
comment to the Engineer of Record. After review and approval, the Engineer will then
submit the material to the HOA.
7
Pressure Irrigation Report
Caldera Canyon Subdivision
Pressure Irrigation Report
Caldera Canyon Subdivision
APPENDIX Ao HYDRAULIC ANALYSIS
E PAN ET2
10
CALDERA CANYON SUBDIVISION
PRESSURE IRRIGATION MODEL
3 2
3
1AE;
4 4 Velocity
F1- g51.73 0.01
1.00
2.50
C�.Ju
5.00
5 fps
6 8 7
.6 11
51.52 0.1;." 51.53
0.33
8
51.50
r
1 0.00
D.00 10 10
yi iAh--`,- ,;.;4
Pressure
25.00
50.00
75.00
100.00
psi
9
2'4
8 9
•
C1. i 8 51 52
M Network Table - Links E=1I=I®
Link ID
Length
ft
Diameter
in
Roughness
Flow
GPM
Velocity
fps
nit Headloss Friction Factor Status
ft/Kft
r
Pipe 2
55
d
41
4�
4'
4
145
145
145
145
76.201
58,40
40.60
1.951
lA9
4,82 0,027 Open
Pipe 3
2.83 0.027 Open
1.68 0.033 Open
Pipe
29
1.04
Pipe 5
116
96
136
22.80
5.00
0.58
0.44 0A28 Open
Pipe 6
145
0.13
0.03 0.040 Open
Pipe 7
4
145
-12.80
033
0.18 0.035 Open
Pipe 3
197
307
4
145
-30.60
0.78
0.79 0,028 Open
Pipe 9
4
145
-48,40
1.24
1.95 0.027 Open
Pipe 10
125
4
145
-66.20
1.69
3.18 0.024 Open
Pump 1
#N/A
#N/A, #N/A,
-119.90 0.000 Open
Network Table -Nodes F--11 El IFff-I
' 11
160,20
0,00,
-119.90 0.000 Open
Elevation Base Demand Head Pressure
Node ID ft GPM ft psi
Junc 2 • � 17.8 2721.40 52.00.
Junc 3 2600,5 17.8 2720.48 51.99
Junc 4 2600.7 17.8 2720.33 51.83
Junc 5 2600.9 17.$ 2720.2$ 51.73
Junc 6 2601.1 17.8 2720.23 51.62
Junc 7 2601.3 17.$ 2720.23 51.53 '.
Junc 8 2601.4 17.8 2720.25 51.50'.
Junc 9 -- 2601.5 - -- _ 17.$ 2720.40 51.52
Junc 10 2601.6. 17.8 2721.00 51.74
Resvr 1 26O1.51 #N1A, 2601.50 0.00
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