HomeMy WebLinkAboutOWTS Soils ReportGnnTIELD CcuNTY OWTS SoIIs RrpoRT
33 MnBLE LRNr, Srrr
Gnnr¡ELD CouNTY, ColonADo
April 2023
Prepared bygSGM
l8 WEST SrxrH Srneer, SulTE 2OO
GleNwooo SpRrNcs, CO A l60 I
970.945. t OO4
970.945.5948 FAX
GnnnELD CouNrY OWTS SorLS REPoRT
33 MnBLE Lnrur, SrLT
GnnnELD Colonnoo
"l hereby affirm that this Onsite Wastewater Treatment System (OWTS) report for 33 Mable Lane,
Silt, Colorado was prepared by me, or under my direct supervision, for the Owners thereof in
accordance with the provisions of Garfield County's OWTS Regulations and approved variances
and exceptions listed thereto. I understand the County does not and will not assume liability for
OWTS facilities designed by others."
License No
Lice rofessional Engineer, State of Colorado (Affix Seal)
PRepRReo By:
JerreRgv S. Slrrlorusoru, PE
SGM Project # CAP
2
äs1 52
s/4/23
Tnslr or Co¡.rrENTS
1.0 lntroduction
2.0 Preliminary lnvestigation
2.1 Property lnformation
2.2 Topography
2.3 Soil Data
2.4 Location of Physical Features
2.5 Additionallnformation
2.6 Landscape Position
2.7 Natural and Cultural Features
2.8 Current and Historic Land Use
3.0 Detailed Soil lnvestigation
3.1 Visual Evaluation
3.2 Tactile Evaluation
4.0 Limitations
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Appendix
Existing Conditions Map
NRCS Soils Report
NRCS Textural Trianqle
SGN/ Soil Ribbon Photos
HP Geotech Soils Report of 2002
5
1.0 lntroduction
The subject property at 33 Mable Lane is on a 312 acre parcel located north and west of
the intersection of Mable Lane and Ukele Lane. The original OWTS for this property was
constructed in 2002 under permit number 3728. This original construction was a chambered
trench installation (21 units in total). The system design was based upon the 3 bedroom
home and a percolation rate performed by Garfield County. This percolation rate was
determined to be 12 minutes per inch.
This past quarter, the current owners of the property have experienced constant back ups of
fluid from the soil treatment area and now are preparing to replace the soil treatment area
with a newer system consisting of chambers and constructed in a "bed" format. lt is the
purpose of this report to identify the soil type and long term acceptance rate based on a
visual and physical soil evaluation of the on-site soils.
2.0 Frelim¡nary I nvestigation
2.1 Property Information
33 Mable Lane. Silt, Colorado
Tract 39A. Antlers Orchard Subdivision. Garfield Countv. Colorado
Existino Structures: 4 Bedroom Home
Domestic Water: On site well
Sepfic; 1250 gallon septic tank with chambered trench soil treatment area
2.2 Topography
Topography in the vicinity of the new OWTS slopes from the southeast to the northwest at grades
between 8 to 10 percent.
2.3 Soil Data
According to the Web Soil Survey for the Natural Resources Conservation Service (NRCS) soils
associated with the subject property are classified as map unit Potts Loam. NRCS soil unit
number 56, which is Potts Loam has grades between (6 to 12) percent. This does agree with
field observations.
NRCS soil data indicates the Potts Loam Soils are acceptable for septic tank absorption fields.
Visual observation of the soils in the excavated test pits indicated the soils have blocky,
moderately weak characteristics.
Plotting the percentages of clay, sand and silt published by the NRCS for this soil unit on the
USDA Textural Triangle indicates the soils would classify as a Clay Loam, soil type 24. Soils
having a classification type of 2A are suitable for absorption fields, having a long-term application
rate (LTAR) of 0.50 gallons per day per square foot of area (gpd/ft2.
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2.4 Location of Physical Features
Physicalfeatures on the subject property that will require minimum horizontal setbacks are shown
in the following Table. All distances are in feet.
Potable Water
Supply Line
10
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STA 25 20 10 5
2.5 Additional Information
a. Easements; N/A
b. Floodplain Maps: N/A
2.6 Landscape Position
The landscape position for the STA is considered on a summit. The slope shape is linear towards
the northwest.
2.7 Natural and Cultural Features
2.8 Gurrent and Historic Land Use
The subject property is in Garfield County's AgriculturalZone. Current and historic use has been
agricultural with the future to remain unchanged.
3.0 Detailed Soil lnvestigation
A detailed soil investigation to determine the depth to the limiting layer, if any, and properly classify
the soil type was conducted on April 28, 2023. Visual evaluation of two soil profile test pits were
conducted in the field and samples collected from each test pit. The soil texture by feel method was
utilized in the field to classify the soil type that will receive wastewater effluent.
Test pits were excavated adjacent to the proposed location for the STA expansion and/or
rehabilitation. The attached existing conditions map identifies the locations of the test holes. Visual
evaluation of þoth test pits was conducted under adequate light conditions, with the soil being in an
unfrozen state.
3.1 Visual Evaluation
Two test pits were excavated by the Owner prior to SGM personnel being on site. The test pits
were labeled by SGM personnel as TP-1 andTP-2.
Test pit TP-1 exhibited medium brown clayey, silty, sandy loam with a fair amount of moisture in
the soil. A ball could be formed but not shaped into a rope. Roots existed in the upper 30-36" of
the test hole. The existing lnfiltrator chambers were at a depth of 42" below grade. Af 5-7' , a light
brown clayey, silty, sandy loam existed. Soil was blocky with moderate structure grade and was
dry.
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Structure with
Basement, Crawl
Space, Footing
Drains
Property
Lines
Septic
Tank
Septic Tank
Effluent Line
5
0
'10
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Test pit TP-2 exhibited a light brown clayey, silty, sandy loam, that was dry. This soil, too, was
blocky with moderate structure grade.
No rock was encountered in either test pits, by visual observation, thus their percentages were
determined to be less than 35 percent.
Excavation was terminated at a depth of 7 feet for TP-1 and 6.5 feet for TP-2. Neither pit showed
signs of:
¡ A limiting layer,¡ Presence of groundwater
Soil observation logs and photos can be found in the Appendix.
All measurements are from ground surface.
3.2 Tactile Evaluation
On April 29, 2023 SGM conducted the soil textural by feel evaluation on the soil samples collected
during the visual evaluation of the test pits. Results of the soil gradation revealed:
1. Total sample size = 1 gallon; both samples
2. Volume of rock > 35 mm (314") = go¡o
3. Volume of rock > 2 mm (0.079") = 9o¿4. Percent rock in sample = 0%
Soils are not type "R".
Performing the soil texture by feel methodology on the non-rock portion of the sample are shown
in the following table.
*Weak < 1 inch; Moderate 1-2 inches; Strong > 2 inches
Mapping NRCS soilgradation onto the TexturalTriangle included with Table 10-1, section 43.10
of Reg43, the NRCS Potts Loam falls in the Type 2A soil classification with blocky, weak
structure.
I
SAMPLE
Sample
Depth from
Ground
Surface lft)
Does Soil
Form a Ball
(yes/no)
Does Soil
Form a
Ribbon
(ves/no)
*Type of Ribbon
Formed (Weak,
Moderate,
Stronq)
How Does the Soil Feel
(G ritty/S mooth/Neithe r)
TH-1 42"Yes Yes Weak e Neither
TH-2 42"Yes Yes Weak e Neither
4.0 Limitations
Our investigation, layout, design, and recommendations are based on site visits and the best
information available at the time. The contents of this letter shall not serve as the basis for any third
party engineering design. lf conditions that are considerably different from those described in this
report are encountered, SGM shall be called to evaluate the conditions. lf the proposed construction
is changed, SGM shall be notified to evaluate the effect of the changes on the OWTS prior to the
changes being made. All construction shall be in accordance with the Garfield County OWTS
Regulations. Pipe type and size, burial requirements, septic tank construction, and other
specifications, which are not depicted in our report, shall conform to the requirements of the County's
OWTS Regulations. The installer of the system shall be acceptable by the County's Environmental
Health Department.
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Appendix
Existing Gonditions Map
NRCS Soils Report
NRCS Textural Triangle
SGM Soil Ribbon Photos
HP Geotech Soils Report of 2AA2
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USDA
-
United States
Department of
Agriculture
NRCS
Natural
Resources
Conservation
Service
A product of the National
Cooperative Soil Survey,
a joint effort of the United
States Department of
Agriculture and other
Federal agencies, State
agencies including the
Agricultural Experiment
Stations, and local
participants
Gustom Soil Resource
Report for
Rifle Area, Golorado,
Parts of Garfield and
Mesa Counties
Paulson OWTS
May 4,2023
Preface
Soil surveys contain information that affects land use planning in survey areas.
They highlight soil limitations that affect various land uses and provide information
about the properties of the soils in the survey areas. Soil surveys are designed for
many different users, including farmers, ranchers, foresters, agronomists, urban
planners, community officials, engineers, developers, builders, and home buyers.
Also, conservationists, teachers, students, and specialists in recreation, waste
disposal, and pollution control can use the surveys to help them understand,
protect, or enhance the environment.
Various land use regulations of Federal, State, and local governments may impose
special restrictions on land use or land treatment. Soil surveys identify soil
properties that are used in making various land use or land treatment decisions.
The information is intended to help the land users identify and reduce the effects of
soil limitations on various land uses. The landowner or user is responsible for
identifying and complying with existing laws and regulations.
Although soil survey information can be used for general farm, local, and wider area
planning, onsite investigation is needed to supplement this information in some
cases, Examples include soil quality assessments (http://www.nrcs.usda.gov/wps/
portal/n rcs/mai n/soi lsihealth/) and certain conservation and engineering
applications. For more detailed information, contact your local USDA Service Center
(https://offices.sc.egov.usda.gov/locator/app?agency=nrcs) or your NRCS State Soil
Scientist (http://wwwnrcs.usda. gov/wpsiportal/nrcs/detail/soils/contactus/?
cid=nrcs1 42p2_05395 1 ),
Great differences in soil properties can occur within short distances. Some soils are
seasonally wet or subject to flooding. Some are too unstable to be used as a
foundation for buildings or roads. Clayey or wet soils are poorly suited to use as
septic tank absorption fields. A high water table makes a soil poorly suited to
basements or underground installations.
The National Cooperative Soil Survey is a joint effort of the United States
Department of Agriculture and other Federal agencies, State agencies including the
Agricultural Experiment Stations, and local agencies, The Natural Resources
Conservation Service (NRCS) has leadership for the Federal part of the National
Cooperative Soil Survey.
lnformation about soils is updated periodically. Updated information is available
through the NRCS Web Soil Survey, the site for official soil survey information,
The U.S. Department of Agriculture (USDA) prohibits discrimination in all its
programs and activities on the basis of race, color, national origin, age, disability,
and where applicable, sex, marital status, familial status, parentalstatus, religion,
sexual orientation, genetic information, political beliefs, reprisal, or because all or a
part of an individual's income is derived from any public assistance program. (Not
all prohibited bases apply to all programs.) Persons with disabilities who require
2
alternative means for communication of program information (Braille, large print,
audiotape, etc.) should contact USDA's TARGET Center al (202)720-2600 (voice
and TDD). To file a complaint of discrimination, write to USDA, Director, Office of
Civil Rights, 1400 lndependence Avenue, S.W., Washington, D.C.20250-9410 or
call (800) 795-3272 (voice) or (202) 72A-6382 (TDD). USDA is an equal opportunity
provider and employer.
3
Gontents
Map Unit Descriptions (Paulson OWTS).......
Rifle Area, Colprado, Parts of Garfield and Mesa Counties
54-Potts loam, 1 to 3 percent slopes..
56-Potts loam, 6 to 12 percent slopes
Soil Information forAll Uses.,..
Soil Reports.
Soil Physical Properties
Physical Soil Properties (Paulson OWTS)..,,.,.
Engineering Properties (Paulson OWTS),.,.....
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Soil Map
The soil map section includes the soil map for the defined area of interest, a list of
soil map units on the map and extent of each map unit, and cartographic symbols
displayed on the map. Also presented are various metadata about data used to
produce the map, and a description of each soil map unit,
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Custom Soil Resource ReportMAP LEGENDMAP INFORMATIONThe soil surveys that comprise your AOI were mapped at1:24,000.Please rely on the bar scale on each map sheet for mapmeasurements-Source of Map: Natural Resources Conservation ServiceWeb Soil Survey URL:Coordinate System: Web Mercator (EPSG:3857)Maps from the Web Soil Survey are based on the Web Mercatorprojection, which preserves direction and shape but d¡stortsdistance and area. A projection that preserves area, such as theAlbers equal-area conic projection, should be used if moreaccurate calculations of distance or area are required.This product is generated from the USDA-NRCS certified data asof the version date(s) listed below.Soil Survey Area: Rifle Area, Colorado, Parts of Garfield andMesa CountiesSurvey Area Data: Version 15, Sep 6, 2022Soil map unils are labeled (as space allows) for map scales1:50,000 or larger.Date(s) aerial images were photographed: Aug 25, 2021-Sep5,2021The orthophoto or other base map on which the soil lines werecompiled and digitized probably differs from the backgroundArea of lnterest (AOl)I Area of lnterest (AOl)Soils] Soil Map Unit PolygonsÊ**r Soil Map Unit LinesI Soil Map Unit PointsSpecial Point Features(Ð BlowoutH¡ Borrow PitH Clay Spol+ Closed DepressionX Gravel Pitf. Gravelly Spot* Landfill,t Lava Flowdh Marsh or swampm Mine or Quarry6 Miscellaneous Water6 Perennial Water\S Rock Outcrop+ Saline Spot;.: sandy spot€ Severely Eroded SpotS S¡nkholeþ Slide or Slipø Sodic SpotË Spoil Areaü Stony Spotß VeryStonySpotq Wet spot.,4 Other.- Special Line FeaturesWater FeaturesStreams and CanalsTransportat¡onH-+ Rails# lnterstate Highways*q'/d US Routes..r.:.. Major Roads' Local RoadsBackgroundI Aerial Photography7Warning: Soil Map may not be valid at this scale.Enlargement of maps beyond the scale of mapping can causem¡sunderstanding of the detail of mapping and accuracy of soilline placement. The maps do not show the small areas ofcontrasting soils that could have been shown at a more detailedscale.
Custom Soil Resource ReportMAP LEGENDMAP INFORMATIONimagery displayed on these maps. As a result, some minorofunit boundariesbe evident.I
Custom Soil Resource Report
Map Unit Legend (Paulson OWTS)
Map Unit Descriptions (Paulson OWTS)
The map units delineated on the detailed soil maps in a soil survey represent the
soils or miscellaneous areas in the survey area. The map unit descriptions, along
with the maps, can be used to determine the composition and properties of a unit.
A map unit delineation on a soil map represents an area dominated by one or more
major kinds of soil or miscellaneous areas. A map unit is identified and named
according to the taxonomic classification of the dominant soils. Within a taxonomic
class there are precisely defined limits for the propefties of the soils. On the
landscape, however, the soils are natural phenomena, and they have the
characteristic variability of all natural phenomena. Thus, the range of some
observed properties may extend beyond the limits defined for a taxonomic class.
Areas of soils of a single taxonomic class rarely, if ever, can be mapped without
including areas of other taxonomic classes. Consequently, every map unit is made
up of the soils or miscellaneous areas for which it is named and some minor
components that belong to taxonomic classes other than those of the major soils.
Most minor soils have properties similar to those of the dominant soil or soils in the
map unit, and thus they do not affect use and management. These are called
noncontrasting, or similar, components. They may or may not be mentioned in a
padicular map unit description. Other minor components, however, have properties
and behavioral characteristics divergent enough to affect use or to require different
management. These are called contrasting, or dissimilar, components, They
generally are in small areas and could not be mapped separately because of the
scale used. Some small areas of strongly contrasting soils or miscellaneous areas
are identified by a special symbol on the maps. lf included in the database for a
given area, the contrasting minor components are identified in the map unit
descriptions along with some characteristics of each. A few areas of minor
components may not have been observed., and consequently they are not
mentioned in the descriptions, especially where the pattern was so complex that it
was impractical to make enough observations to identify allthe soils and
miscellaneous areas on the landscape.
The presence of minor components in a map unit in no way diminishes the
usefulness or accuracy of the data. The objective of mapping is not to delineate
pure taxonomic classes but rather to separate the landscape into landforms or
landform segments that have similar use and management requirements. The
delineation of such segments on the map provides sufficient information for the
development of resource plans. lf intensive use of small areas is planned, however,
I
Map Unit Symbol Map Unit Name Acres ¡n AOI Percent of AOI
54 Potts loam, 1 to 3 percent
slopes
1.8 99.9%
56 Potts loam, 6 to 12 percent
slopes
0.0 0.1%
Totals for Area of lnterest 1.8 100.0%
Custom Soil Resource Report
onsite investigation is needed to define and locate the soils and miscellaneous
areas.
An identifying symbol precedes the map unit name in the map unit descriptions.
Each description includes general facts about the unit and gives important soil
properties and qualities.
Soils that have profiles that are almost alike make up a so/ senes. Except for
differences in texture of the surface layer, all the soils of a series have major
horizons that are similar in composition, thickness, and arrangement.
Soils of one series can differ in texture of the surface layer, slope, stoniness,
salinity, degree of erosion, and other characteristics that affect their use. On the
basis of such differences, a soil series is divided inlo soil phases. Most of the areas
shown on the detailed soil maps are phases of soil series. The name of a soil phase
commonly indicates a feature that affects use or management. For example, Alpha
silt loam, 0 to 2 percent slopes, is a phase of the Alpha series.
Some map units are made up of two or more major soils or miscellaneous areas.
These map units are complexes, associations, or undifferentiated groups.
A complex consists of two or more soils or miscellaneous areas in such an intricate
pattern or in such small areas that they cannot be shown separately on the maps.
The pattern and proportion of the soils or miscellaneous areas are somewhat similar
in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example.
An assocrafion is made up of two or more geographically associated soils or
miscellaneous areas that are shown as one unit on the maps. Because of present
or anticipated uses of the map units in the survey area, it was not considered
practical or necessary to map the soils or miscellaneous areas separately. The
pattern and relative proportion of the soils or miscellaneous areas are somewhat
similar. Alpha-Beta association, 0 to 2 percent slopes, is an example.
An undifferentiated group is made up of two or more soils or miscellaneous areas
that could be mapped individually but are mapped as one unit because similar
interpretations can be made for use and management. The pattern and proportion
of the soils or miscellaneous areas in a mapped area are not uniform. An area can
be made up of only one of the major soils or miscellaneous areas, or it can be made
up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example.
Some surveys include miscellaneous areas. Such areas have little or no soil
material and support little or no vegetation. Rock outcrop is an example.
10
Custom Soil Resource Report
Rifle Area, Colorado, Parts of Garfield and Mesa Counties
S4-Potts loam, I to 3 percent slopes
Map Unit Setting
National map unit symbol: jnyq
Elevation: 5,000 to 7,000 feet
Farmland classification: Prime farmland if irrigated
Map Unit Composition
Potts and similar so/s: 85 percent
Estimates are based on observations, descriptions, and fransecfs of the mapunit.
Description of Potts
Setting
Landform: Mesas, benches, valley sides
Down-slope shape: Convex, linear
Across-s/op e shape : Convex, linear
Parent material: Alluvium derived from basalt and/or alluvium derived from
sandstone and shale
Typical profile
H1 -0to4inches: loam
H2 - 4 to 28 inches: clay loam
H3 - 28 to 60 inches.' loam
Properties and qualities
S/ope:lto3percent
Depth to restrictive feature: More than 80 inches
Drainage c/ass.' Well drained
Runoff class: Medium
Capacity of the most limiting layer to transmit water (Ksat); Moderately high (0.20
to 0.60 in/hr)
Depth to water table: \liore than B0 inches
Frequency of flooding: None
Frequency of ponding: None
Calcium carbonate, maximum content: l5 percent
Maximum salinity: Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm)
Available water supply,0 to 60 inches: High (about 10.3 inches)
Interpretive groups
Land capability classification (irrigated): 3e
Land capability classification (nonirrigated): 3c
Hydrologic Soil Group: C
Ecologicalsife; R04BAY306UT - Upland Loam (Wyoming Big Sagebrush)
Hydric soil rafing: No
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Custom Soil Resource Report
56-Potts loam, 6 to 12 percent slopes
Map Unit Setting
National map unit symbol: jnys
Elevation: 5,000 to 7,000 feet
Farmland classification: Farmland of statewide importance
Map Unit Composition
Potts and similar so/s; 85 percent
Estimates are based on obseruations, descriptions, and transects of the mapunit.
Description of Potts
Setting
Landform: Mesas, benches, valley sides
Down-slope shape: Convex, linear
Across-s/op e shape : Convex, linear
Parent material: Alluvium derived from basalt and/or alluvium derived from
sandstone and shale
Typical profile
H1 -0to4inches: loam
H2 - 4 to 28 inches: clay loam
H3 - 28 to 60 inches: loam
Properties and qualities
S/ope: 6 to 12 percent
Depth to restrictive feature: More than 80 inches
Drainage c/ass; Well drained
Runoff class; High
Capacity of the most limiting layer to transmit water (Ksat); Moderately high (0.20
to 0.60 in/hr)
Depth to water table: \llore than 80 inches
Frequency of flooding: None
Frequency of ponding: None
Calcium carbonate, maximum content: 15 percent
Maximum salinity: Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm)
Available water supply, 0 to 60 inches: High (about 10.3 inches)
lnterpretive groups
Land capability classification (irrigated): 4e
Land capability classification (nonirrigated): 4e
Hydrologic Soil Group: C
Ecologicalsife: R04BAY306UT - Upland Loam (Wyoming Big Sagebrush)
Hydric soil rating: No
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So Information for All Uses
Soil Reports
The Soil Reports section includes various formatted tabular and narrative reports
(tables) containing data for each selected soil map unit and each component of
each unit. No aggregation of data has occurred as is done in reports in the Soil
Properties and Qualities and Suitabilities and Limitations sections.
The reports contain soil interpretive information as well as basic soil properties and
qualities. A description of each report (table) is included.
Soil Physical Properties
This folder contains a collection of tabular reports that present soil physical
properties. The reports (tables) include all selected map units and components for
each map unit. Soil physical properties are measured or inferred from direct
observations in the field or laboratory. Examples of soil physical properties include
percent clay, organic matter, saturated hydraulic conductivity, available water
capacity, and bulk density.
Physical Soil Properties (Paulson OWTS)
This table shows estimates of some physical characteristics and features that affect
soil behavior. These estimates are given for the layers of each soil in the survey
area. The estimates are based on field observations and on test data for these and
similar soils.
Depth to the upper and lower boundaries of each layer is indicated.
Particle size is the effective diameier of a soil particle as measured by
sedimentation, sieving, or micrometric methods. Particle sizes are expressed as
classes with specific effective diameter class limits. The broad classes are sand,
silt, and clay, ranging from the larger to the smaller.
Sand as a soil separate consists of mineral soil particles that are 0.05 millimeter to 2
millimeters in diameter. ln this table, the estimated sand content of each soil layer is
given as a percentage, by weight, of the soil material that is less than 2 millimeters
in diameter.
S/f as a soil separate consists of mineral soil particles that are 0.002 to 0.05
millimeter in diameter. ln this table, the estimated silt content of each soil layer is
13
Custom Soil Resource Report
given as a percentage, by weight, of the soil material that is less than 2 millimeters
in diameter.
Clay as a soil separate consists of mineral soil particles that are less than 0.002
millimeter in diameter. ln this table, the estimated clay content of each soil layer is
given as a percentage, by weight, of the soil material that is less than 2 millimeters
in diameter.
The content of sand, silt, and clay affects the physical behavior of a soil. Particle
size is important for engineering and agronomic interpretations, for determination of
soil hydrologic qualities, and for soil classification.
The amount and kind of clay affect the fertility and physical condition of the soil and
the ability of the soil to adsorb cations and to retain moisture. They influence shrink-
swell potential, saturated hydraulic conductivity (Ksat), plasticity, the ease of soil
dispersion, and other soil properties. The amount and kind of clay in a soilalso
affect tillage and earthmoving operations.
Moist bulk density is the weight of soil (ovendry) per unit volume. Volume is
measured when the soil is at field moisture capacity, that is, the moisture content at
113- or 1110-bar (33kPa or lOkPa) moisture tension. Weight is determined after the
soil is dried at 105 degrees C. ln the table, the estimated moist bulk density of each
soil horizon is expressed in grams per cubic centimeter of soil material that is less
than 2 millimeters in diameter. Bulk density data are used to compute linear
extensibility, shrink-swell potential, available water capacity, total pore space, and
other soil properties. The moist bulk density of a soil indicates the pore space
available for water and roots. Depending on soil texture, a bulk density of more than
1.4 can restrict water storage and root penetration. Moist bulk density is influenced
by texture, kind of clay, content of organic matter, and soil structure.
Saturated hydraulic conductivity (Ksat)refers to the ease with which pores in a
saturated soil transmit water. The estimates in the table are expressed in terms of
micrometers per second. They are based on soil characteristics observed in the
field, particularly structure, porosity, and texture. Saturated hydraulic conductivity
(Ksat) is considered in the design of soil drainage systems and septic tank
absorption fields.
Available water capacity refers to the quantity of water that the soil is capable of
storing for use by plants. The capacity for water storage is given in inches of water
per inch of soil for each soil layer. The capacity varies, depending on soil properties
that affect retention of water. The most important properties are the content of
organic matter, soil texture, bulk density, and soil structure. Available water capacity
is an important factor in the choice of plants or crops to be grown and in the design
and management of irrigation systems. Available water capacity is not an estimate
of the quantity of water actually available to plants at any given time.
Linear extensibility refers to the change in length of an unconfined clod as moisture
content is decreased from a moist to a dry state. lt is an expression of the volume
change between the water content of the clod al1l3- or 1110-bar tension (33kPa or
1OkPa tension)and oven dryness. The volume change is reported in the table as
percent change for the whole soil. The amount and type of clay minerals in the soil
influence volume change.
Linear extensibility is used to determine the shrink-swell potential of soils. The
shrink-swell potential is low if the soil has a linear extensibility of less than 3
percent; moderate if 3 to 6 percent; high if 6 to 9 percent; and very high if more than
9 percent. lf the linear extensibility is more than 3, shrinking and swelling can cause
14
Custom Soil Resource Report
damage to buildings, roads, and other structures and to plant roots. Special design
commonly is needed.
Organic matter is the plant and animal residue in the soil at various stages of
decomposition. ln this table, the estimated content of organic matter is expressed
as a percentage, by weight, of the soil material that is less than 2 millimeters in
diameter. The content of organic matter in a soil can be maintained by returning
crop residue to the soil.
Organic matter has a positive effect on available water capacity, water infiltration,
soil organism activity, and tilth. lt is a source of nitrogen and other nutrients for
crops and soil organisms.
Erosion factors are shown in the table as the K factor (Kw and Kf) and the T factor.
Erosion factor K indicates the susceptibility of a soil to sheet and rill erosion by
water. Factor K is one of six factors used in the Universal Soil Loss Equation
(USLE) and the Revised Universal Soil Loss Equation (RUSLE) to predict the
average annual rate of soil loss by sheet and rill erosion in tons per acre per year.
The estimates are based primarily on percentage of silt, sand, and organic matter
and on soil structure and Ksat. Values of K range from 0.02 to 0.69. Other factors
being equal, the higher the value, the more susceptible the soil is to sheet and rill
erosion by water.
Erosion factor Kw indicates the erodibility of the whole soil. The estimates are
modified by the presence of rock fragments.
Erosion factor Kf indicates the erodibility of the fine-earth fraction, or the material
less than 2 millimeters in size.
Erosion factor f is an estimate of the maximum average annual rate of soil erosion
by wind and/or water that can occur without affecting crop productivity over a
sustained period. The rate is in tons per acre per year.
Wind erodibility groups are made up of soils that have similar properties affecting
their susceptibility to wind erosion in cultivated areas. The soils assigned to group 1
are the most susceptible to wind erosion, and those assigned to group 8 are the
least susceptible. The groups are described in the "National Soil Survey Handbook."
Wind erodibility index is a numerical value indicating the susceptibility of soil to wind
erosion, or the tons per acre per year that can be expected to be lost to wind
erosion. There is a close correlation between wind erosion and the texture of the
surface layer, the size and durability of surface clods, rock fragments, organic
matter, and a calcareous reaction. Soil moisture and frozen soil layers also
influence wind erosion.
Reference:
United States Department of Agriculture, Natural Resources Conservation Service.
National soil survey handbook, title 430-Vl. (http://soils.usda.gov)
15
Custom Soil Resource ReportThree values are provided to identify the expected Low (L), Representative Value (R), and High (H).Physlcal Soil Properties-Rifle Area, Colorado, Parts of Garfield and Mesa CountiesWinderodibilityindex5656Winderodibilitygroup55ErosionfactorsT55Kf373237.37.ó¿.37Kw373237.37.32.37OrganicmatterPct1.0- 1.5-2.O0.5- 0.8-1.00.0- 0.3-0.51.0- 1.5-2.00.5- 0.8-1.00.0- 0.3-0.5LinearextensibilityPct0.0- 1.5- 2.93.0- 4.5- 5.90.0- 1.5- 2_90.0- '1.5- 2.93.0- 4.5- 5.90.0- 1.5- 2.9AvailablewatercapacityIn/ln0.14-0.16-0.'l70.17-0.19-0.200-14-0-16-0.170.1 4-0.1 6-0.170.17-0.19-0.200.1 4-0.1 6-0.17Saturatedhydraulicconductivitymicro m/sec4.23-23.28-42.341.41-2.82-4.234.23-23.28-42.344.23-23.28-42.341.41-2.82-4.234.23-23.28-42.34Moistbulkdensityg/cc1.25-1.33-1.401.25-1.33-1401.25-1.33-1.401.25-1 .33-1.401.25-1.33-1.401.25-1 .33-1.40ClayPct10-15- 2027-31- 3415-20- 2510-15- 2027-31- 3415-20- 25s¡ttPct41--Jb--38--41--36--38-SandPct-44--33--42--44--33--42-DepthIn0-44-2828-600-44-2828-60Map symboland soil nameS4-Potts loam,1 to 3 percentslopesPotts56-Potts loam,6to 12percentslopesPottsl6
Custom Soil Resource Report
Engineering Propert¡es (Paulson OWTS)
This table gives the engineering classifications and the range of engineering
properties for the layers of each soil in the survey area.
Hydrologic soil group is a group of soils having similar runoff potential under similar
storm and cover conditions. The criteria for determining Hydrologic soil group is
found in the National Engineering Handbook, Chapter 7 issued May 2007(http:ll
directives.sc.egov.usda.gov/OpenNonWebContent.aspx?contenl=17757 .wba).
Listing HSGs by soil map unit component and not by soil series is a new concept for
the engineers. Past engineering references contained lists of HSGs by soil series.
Soil series are continually being defined and redefined, and the list of soil series
names changes so frequently as to make the task of maintaining a single national
list virtually impossible. Therefore, the criteria is now used to calculate the HSG
using the component soil properties and no such national series lists will be
maintained. All such references are obsolete and their use should be discontinued.
Soil properties that influence runoff potential are those that influence the minimum
rate of infiltration for a bare soil after prolonged wetting and when not frozen. These
properties are depth to a seasonal high water table, saturated hydraulic conductivity
after prolonged wetting, and depth to a layer with a very slow water transmission
rate. Changes in soil properties caused by land management or climate changes
also cause the hydrologic soil group to change. The influence of ground cover is
treated independently. There are four hydrologic soil groups, A, B, C, and D, and
three dual groups, A,/D, B/D, and C/D. ln the dual groups, the first letter is for
drained areas and the second letter is for undrained areas.
The four hydrologic soil groups are described in the following paragraphs:
Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly
wet. These consist mainly of deep, well drained to excessively drained sands or
gravelly sands. These soils have a high rate of water transmission.
Group B. Soils having a moderate infiltration rate when thoroughly wet. These
consist chiefly of moderately deep or deep, moderately well drained or well drained
soils that have moderately fine texture to moderately coarse texture. These soils
have a moderate rate of water transmission.
Group C. Soils having a slow infiltration rate when thoroughly wet. These consist
chiefly of soils having a layer that impedes the downward movement of water or
soils of moderately fine texture or fine texture. These soils have a slow rate of water
transmission.
Group D. Soils having a very slow infiltration rate (high runoff potential) when
thoroughly wet. These consist chiefly of clays that have a high shrink-swell
potential, soils that have a high water table, soils that have a claypan or clay layer at
or near the surface, and soils that are shallow over nearly impervious material.
These soils have a very slow rate of water transmission.
Depth to the upper and lower boundaries of each layer is indicated.
Texture is given in the standard terms used by the U.S. Department of Agriculture.
These terms are defined according to percentages of sand, silt, and clay in the
fraction of the soil that is less than 2 millimeters in diameter. "Loam," for example, is
soil that is 7 to 27 percent clay,28 to 50 percent silt, and less than 52 percent sand.
lf the content of particles coarser than sand is 15 percent or more, an appropriate
modifier is added, for example, "gravelly."
17
Custom Soil Resource Report
Classification of the soils is determined according to the Unified soil classification
system (ASTM, 2005) and the system adopted by the American Association of
State Highway and Transportation Officials (AASHTO, 2004).
The Unified system classifies soils according to properties that affect their use as
construction material. Soils are classified according to particle-size distribution of
the fraction less than 3 inches in diameter and according to plasticity index, liquid
limit, and organic matter content. Sandy and gravelly soils are identified as GW, GP,
GM, GC, SW, SP, SM, and SC; silty and clayey soils as ML, CL, OL, MH, CH, and
OH; and highly organic soils as PT. Soils exhibiting engineering properties of two
groups can have a dual classification, for example, CL-ML.
The AASHTO system cfassifies soils according to those properties that affect
roadway construction and maintenance. ln this system, the fraction of a mineral soil
that is less than 3 inches in diameter is classified in one of seven groups from A-1
through A-7 on the basis of particle-size distribution, liquid limit, and plasticity index.
Soils in group A-1 are coarse grained and low in content of fines (silt and clay). At
the other extreme, soils in group A-7 are fine grained. Highly organic soils are
classified in group A-8 on the basis of visual inspection.
lf laboratory data are available, the A-1 , A-2, and A-7 groups are further classified
as A-1-a, A-1-b, A-2-4, A-2-5, A-2-6, A-2-7, A-7-5, or A-7-6. As an additional
refinement, the suitability of a soil as subgrade material can be indicated by a group
index number. Group index numbers range from 0 for the best subgrade material to
20 or higher for the poorest.
Percentage of rock fragments larger than 10 inches in diameter and 3 to 10 inches
in diameter are indicated as a percentage of the total soil on a dry-weight basis. The
percentages are estimates determined mainly by converting volume percentage in
the field to weight percentage. Three values are provided to identify the expected
Low (L), Representative Value (R), and High (H).
Percentage (of soil particles) passrng designated sieves is the percentage of the soil
fraction less than 3 inches in diameter based on an ovendry weight. The sieves,
numbers 4, 10, 40, and 200 (USA Standard Series), have openings of 4.76,2,00,
0,420, and 0.074 millimeters, respectively. Estimates are based on laboratory tests
of soils sampled in the survey area and in nearby areas and on estimates made in
the field. Three values are provided to identify the expected Low (L), Representative
Value (R), and High (H).
Liquid limit and plasticity lndex (Atterberg limits) indicate the plasticity
characteristics of a soil. The estimates are based on test data from the survey area
or from nearby areas and on field examination. Three values are provided to identify
the expected Low (L), Representative Value (R), and High (H).
References:
American Association of State Highway and Transportation Officials (AASHTO).
2004. Standard specifications for transportation materials and methods of sampling
and testing. 24th edition.
American Society for Testing and Materials (ASTM). 2005. Standard classification of
soils for engineering purposes. ASTM Standard D2487-00.
18
Custom Soil Resource ReportAbsence of an entry indicates that the data were not estimated. The asterisk '*' denotes the representative texture; otherpossible textures follow the dash. The criteria for determining the hydrologic soil group for individual soil components isfound in the National Engineering Handbook, Chapter 7 issued May 2007(http://directives.sc.egov.usda.gov/OpenNonWebContent.aspx?content=17757.wba). Three values are provided to identify the expected Low (L),Representative Value (R), and High (H).Englneerlng Properties-Rlfle Area, Golorado, Parts of Garfield and Mesa Count¡esPlasticity indexL-R-H5-8 -1010-15-205-8 -105-8 -1010-15-205-8 -10LiquidlimitL-R-H25-28-3030-35-4025-28-3025-28-3030-354025-28-30Percentage passing sieve number-200L-R-H60-68-7570-75-8060-68-7560-68-7570-75-8060-68-7540L.R-H85-90-9590-95-10085-90-9585-90-9590-95-10085-90-9510L-R-H1 00-1 00-1001 00-1 00-1 001 00-1 00-1 00't00-'t 00-1 001 00-1 00-1001 00-1 00-1004L-R-H1 00-1 00-l 001 00-1 00-1001 00-1 00-1001 00-1 00-100100-'100-1 001 00-l 00-100Pct Fragments3-10inchesL-R-H0-0-00-0-00-0-00-0-00-0-00-0-0>10inchesL-R-H0-0-00-0-00-0-00-0-00-0-00-0-0GlassificatlonAASHTOA4A-6N4A-4A-6A-4UnifiedCL.ML,CLCLCL-MLCLCL-ML,CLCLCL-ML,CLUSDA textureLoamClay loamLoamLoamClay loamLoamDepthIn044-2828-600-44-2828-60Hydrolog¡cgfoupccPct. ofmapunit85B5Map unit symbol andsoíl nameS4-Potts loam, 1 to 3percent slopesPotts56-Potts loam, 6 tol2 percent slopesPotts19
BASED ON REGULATION 43 TABLE 1O-1
For Soils with Less Than 35 Percent Rock Fragments. Rock Fragments are larger than 2 millimeters'
soil Treatment Area Long Term Acceptance Rates by soil Texture, soil structure, Percolation Rates and rreatment level
Long-term Acceptance Rate ([
day per square foot
TAR)
Gallons perSoil Type, Texture, Structure and Percolation Rate Range
Level 3N1*
Tfeatment
Level 2N1
Treatment
Level 31
Treatment
Level 21
TreatmentPercolation
Rate (MPl)Level 11
TreatmentUsDA so¡l
Stfucture-SoilType UsDA so¡l Texture
USDA So¡l
Structure-Grade
1.101.101.000.60 1.00
i¡iiii}¡ÀéÉe
Moderate
Strong
t6-25
@
Prismatic
Blocky
Granular
l¿:ërË::;
Sandy Loam
Loam
S¡lt Loam
Pr¡smatic
Blocky
Granular
Weak
0.90 0.900.800.50 0.8026-40
Massive Structureless
Sandy Loam
Loam
Silt Loam
0.650.650.55
Weak
Moderate
Strong
Prismatic
Blocky
Granular
Prismatic
Blocky
Grãnular 0.55 0.5s0.45
41-60
6t-75
0.35 0.5s
0.30
I
I
I
StructurelessMassive
Sandy Clay Loam
Clay Loam
Silty Clay Loam
Sandy Clay Loam
Clay Loam
silty Clãy Loam
0.15 0.150.15 0.15I2l+0.10
Weak
Moderate
Strong
Soil Types 2-44 Plâty5
2A
2
3
3A
I
Treatment levels are defined in Table 6'3
lRr""r outside the dashed box require design by a professional eng¡neer
100
10Textural
Triangle
'wm
!dtåyF:t,ot'¡A
20
100 90 80
20
50 40
80
30
40
Soil Type 2 or 2A
ffimd&
10
NRCS Soil profile
classification range,
Type 2A
Sand
20 10
100
Soil Texture by Feel
Place soil in palm of hand. Add water drop-wise
and knead the soil into a smooth and plastic
consistency, like moist
putty.
Place ball of soil between thumb and forefinger,
gently pushing the soil between with the thumb,
squeezing it upward into a ribbon. Form a ribbon
of uniform thickness and width. Allow
ribbon to emerge and extend
over the forefingeç
breaking from
its own
weight.
B¿sed on USDA NR(5 Guide t0Texture by teel - S. J.]hien,19i9, modified.
Th¡s varial¡0n (reated by 0 Hanison, M Brown, W Brown, R Laws.
Forms a weak
ribbon less
than 1" before
breaking
Loam
Soil Type 2 or 2A
Sandy loam
Silt loam
È
Add dry soilwater
ls the soiltoo dry?
Yes
No
the soiltoo wet?
Yes
NoApplicable for both
TH-1 and TH-2
the soil remain in a ballwhen squeezed?
No
the soilform a ribbon?
No
it form?
Does soil feel very gritty? Yes
No
Does soilfeelvery smooth? Yes
No
Neither gritty nor smooth? Yes
Claylonm
SollType3iiilJA
fçnili;ärv'f*Éf,ñi'
sfltl{l-¡y
lorfii
' : i.-.,.
Clrylo¡¡r
Forms 1 -2',
ribbon re
ffi
ffi
ffi
ffi
Forms a
ribbon 2"or
longer before
breaking
3
2
loam
lf platy structure then soil type 5
0
Heprvorlh.Par¡,l¡k C*orechnics¡, Inc.
5020 County Road 154
Gle¡rroad Springs, Coloredo 81601
Phone: 97t.945-79tt
Fex: 9f0.945.t154
hpgeo@hpgeolcch.com
May 30, 2002
Rob Crawford
120I Fir Avenue
Rifle, Colorado 81650 Job No. LV¿361
Subject;Subsoil Study for Fouudation Design, Proposed Crawford Residence,
Pa¡cel 394, UkúFtang, Garfield County, Colorado.
Dear Mr. Crawford:
As requested, llepworth-Pawlak Geotechnical, Inc. performed a subsoil study for
design of foundations at the subject site. The study was condueted h accordance with
our agreement for geotechnical engineering services to you dated May 22,2002. The
dat¿ obtained and our recornnrendations based o[ tbe proposed coostruction and
subsurface conditions encouutered are presented in this report.
Proposed Construction: The pro¡rosed residence will be a single story manufactured
stn¡cture over a walkout basement level located on tbe site as sho\ryn on Fig. l. Ground
floor will be slab+u-grade. Cut depths ¿ue expected to r¡ngÊ benveen about 3 ro I feet.
Foundation loadings for this rype of construction are assunod to be relatively light and
typ¡cal of tbe proposed type of construction.
lf building conditions or foundâtion loadhgs are siguificautly different from those
described above, we should be notiñed to re-evaluate the recornmendations presented in
this report.
SÍte Conditions: Thc site was vacant at the time of our field cxploration. The ground
surface in the building area is reladvely flat with a gentle slope down to the nortb and
about 2 to 3 feet of elevation difference. A dr?inâge borders the uorthern ponion of the
property. Vegetation consists of grass and weeds. Sagebrush and cononwood tees are
located along the northcrn drainage.
Subsurface Conditious: The subsurface conditions at the site were evaluatcd by
observing nro exploratory pits at the approximate locatious shown on Fig. l. The pits
had been excavated prior to our arrival ou-site. The logs of the pits are presentd on
Fig. 2. The subsoils encousteretl, below about I foot of topsoil, consist of medium stiff
to stiff, sandy to very sandy clay and silt. Results of swell-consolidation testing
perforured on rclatively undisrurbed samples of the silt and clay soils, presenred on
Figs. 3 and 4, generally indicate lorv to moderate comprcssibility under conditions of
loading and wetting. The sample Fom Pit I at 3 feet showed a minor collapse potential
H
Rob Crawford
May 30,2002
Page2
(senlement under constant load) when wencd, No frec warer was observed in the pits at
the time of excavation and the soils were slightly uroist to moist.
Fouudation Recommendations; ConsÍdering the subsoil condidons encountered i¡ the
exploratory piæ and the nature of the proposed consh¡ction, tve reco¡umend spread
foodngs placed on the undisturbed natural soil designed for an allowable soil bearing
pressure of 1,500 psf for suppon of the proposed resídence. The soils tend ro compress
after wening under load aud there could be some post-construcdon foundation
settlernent. The amount of senlement would depend on tbe depth and extent of
subsurface wening and coukl be on the o¡der of I to 2 i¡ches. Footings should be a
minimum width of l8 inches for continuous walls and,2 feer for columns. Loose and
disturbed soils encountered at the fou¡datiou bearing level witbin the excavatiou should
be removed and the footing bearing level extended down to the undisturbed natural
soils. The exposed subgrade should be moistened and compacted prior to placing
concrete. Exterior footings should be provided witb adequate cover above their bearing
elevatioru for frost protectÍon. Placement of footings at leæt 36 i¡ches below tle
exterior grade is typically used in tl¡is area. Conti¡uous foundation walls should be
reinforced top and bonom to span local auomalies such as by assuming an unsuppgned
length of at least 12 fcet. Fouudation walls acting ås reuining structures should be
designed to resist a lateral earth pressure based on an equivalent fluid unit weight of at
least 55 pcf for the on-site soil as backfill.
Floor $labs: Tbe natural on-site soils, exclusive of topsoil, are suitable to suppon
lightly loaded slab-on-grade constructiou. The clay and silt soils are compressible when
wcttd. To reduce the effects of some differential rnovement, floor slabs should be
separatd from all bearing walls and colurnns with expansion joinu which allow
unresuained vertical movement. Floor slab controt joints should be used to reduce
damage due to shrinkage cracking. The requirements for joint spacing and slab
reinforcement should be established by the designer based on experience and the
intended slab use. A milimum 4 inch layer of freedraining gravel should be ptaced
beneath basement level slabs to faciliate drainage and for subgrade suppon. This
mate¡ial should consist of mi¡us 2 i¡ch aggregate with less than 50% passing rhe No. 4
sieve and less tban 2% passing the No. 200 sieve.
A.ll flúl materials for support of floor slabs should be compacted to at least gS% of
maxÍ¡num standa¡d Proctor densiry at a moisn¡re contenr neår optirnum. Required Frll
c¿n consist of the on-site soils devoid of vegetation and topsoil.
Underdrain System: Although free water was not encoutrtered during our exploration,
it has been our experience in the area that local perched groundwater can develop
during drnes of heavy precipiution or seasonal runoff. Frozen ground during spring
runoff caû cteate a perched condition. lvVe recommend below-grade construction, such
H-P Giorecx
Rob Crawford
May 30,2002
Page 3
as retainiug walls and basement areas, be protected from wening and hydrostatic
pressure buildup by an underdrain sysrem.
The draÍns should consist of drainpþ placed in the bortom of tbe wall backñll
surrounded above ùe i¡vert level with free-draining granular material. The drai¡
should be placed at each level of excavation and at least I foot below lowest adjacent
frnish grade and sloped at a minimum 1% to a sui¡able gravity outlet. Free-draining
granular material used in the underdrain system should contais less than 2% passing the
No, 200 sicve, Iess than 50% passing the No. 4 sieve and bave a maximum size of
2 inches. The drain gravel backñtl should be at least t¡lz feet deep. An impervious
membra¡e such as 20 mil PVC should bc placed beneath the drain gravel in a nougb
shape and anached to the foundation wall with mastic to prevent wening of the bearing
soils.
Surface Drainage: The following drainage precautioru should be observed during
coßtruction and maiståined at all dmes after the residence has been completed:l) Inundation of the foundatio¡ excavations and uuderslab areas should be
avoided during construction.2) Exterior backfrll sbould be adjusted to near optimum moisn¡re and
compacted to at lear¡t 95% of the maximum standa¡d Proctor density in
pavement and slab areas and to at least 9O% of the maximum standffd
Proctor densiry in landscape areas. Freedraining wall backfill should be
capped with about 2 feet of the on-site, finer graded soils to reduce
surface water infrltration.3) The ground surface surrounding the exterior of the building should be
sloped to drain away from the fouodation in all directions. We
recommend a minimum slope of 6 inches in the fust l0 feet in uupaved
areas and a minimum slope of 3 inches in the frrst l0 feet in pavemÊnt
and walhvay areas.4) Roof downspouts and drains should discharge well beyond the limia of
all backfill.
5) Landscaping which requires regular heavy irrigation, such as sod, should
be located at least 5 feet from the building.
Limitatio¡s: This srudy has been conducted in accordancc with generally accepted
leotechnical engioeering principles and practices in this area at this time. We rnake no
wärranty either expressed or implied. The conclusions and recommendations submitted
in this report are based upon the data obtained from the exploratory pits excavated at the
locations i¡dicated on Fig. I and to the depths shown on Fig. 2, the proposed type of
construçtion, and our experience in the area. Our fimlings include interpolation and
extrapolation of the subsurface conditions identified at the exploramry pits aad
variations in thc subsurface conditions may Dot become evident until excavation is
performed. If conditions encouutered during construcdon appear different from those
H.P GEoiËcH
Rob Ctawforil
May 30, 2002
Page 4
dcscribed in this report, we should be aotifîed ar oncç so re-evaluation of the
recommendations may be rnade.
This report has been prepared for tbe exclusive use by our client for design purposes.
We are not respoûsible for techdcal interpretations by others of our informaì¡on. ns
the project evolves, we should provide continued consultation and field services during
coûstruction to review and monitor rhe implemenudotr of our recommendatiogs, and io
verify that the recommendations have bcen appropriately inte¡preted. Significant design
changes may require additional analysis or modificarions to the recomn¡endations
presentd herein. lffe recommend on-sitc observation of excavations and founclation
bearing strata and testing of structural ñll by a representative of the geotechnical
eugineer.
If you have any questions or if we may be of further assisrä.nce, please let us know.
Sincerely,
HEPWORTH - PA1VLAK G , INC.
Jordy Z. Adamson Jr.
Reviewed by:
ft;r.
Steven L. Pawlak, P.E.
JZAlksw
anechments
29707
H-P GÊo:¡cH
APPROX¡MATE SCALE1' - 60'
.ÍRACT 598
PROPOS€D
RESIDENCE
\\
I
I lPrT2
l¡Jz
5
Jl¡¡o
:r
PITl T
,
I
t
I
PROPERW
EOUNDARIES
102 361 HEPWORTH - PAWLAK
GEOTECHNICAL, INC.LOCATION OF EXPLORATORY PITS Fis. 1
PIT 1 PIT 2
0
rcrtA!
0O-l0Íl
5 ft-20.0gO-99
-ZOO-E¡!
tÀE27
Pl-?
ã
rc-Ît.Î
ItO-lO¡¡
-200r?0
10 10
I.EGEND:
fOPSOlb Eondy eilt ond cloy, orgonfce, slightty moiÈt, brown.
C[-AY AND.SILT (Cl--ML); eondy to ræry eondy, etrotifiad, rñcdium etilf to ¡ilff, moist, brom,low ploaticlty.
þ 2' Dicmeter hond drlvcn llner aomplc.
NOÌES:
1. Explorotory p¡ts usrc .xcovotcd prior to our stte visit on Moy 22, ZOg2,
2' Locotlons of axplorctory plts w€ra rnâosrtrod opproxímotely by poclng from leotures on thr rlte plon
provldod.
3. Ecwtlone of cxPlorotory pfts wsre not meosurcd ond loge ol explorotory plts ore drown to dçth.Plt 1 ¡0 obout 2 to 3 fcct hlgher thon Plt 2.
+. Ih!. Ëxp¡orotory plt locotlong should bc cmaidcr¿d occurotc only to ths dogrec lmplled by themctlrod uged.
5. the llnce between moteriols shown on thâ erglorotory pit logs reprasent the opproximotc boundorle¡battaen moterlol t¡çcs ond tronsltlonc moy be groduoi.
6. No fse wotcr roe €ncount¿rcd ln the pltr of thß tlme of obserwtlon. Fluctuotlons in wotsr laræl moyôccur slth timc.
7. Loborotory Testlng Resultsl
ffi=tïoterContcnt(Z)
DD - Dry Dcnstty ( pcf )
-200 - Fcrccnt p.oeaing No. 200 elevcLL=LiguidUmit(Z)-
Pl - Plosticity tndex ( Z )
0
ool¡-
I
E
ô,oê
øol!
I
E
Àoo
rc-Ð.30Ht¡
102 361
HEPWORTH-PAWLAK
GEOTECHNICAL, INC.LOGS OF EXPLORATORY PITS Fig. 2
0
}t1
2
J
4
0.1 r.o 10
APPUED PRESSURE - ksf
100
0
N
Ëo
g,oo
o.Ê
o()
2
3
10
APPUED PRESSURE - kof
Moígturc Content - 18.5
Ory Dansity - 1O2
Scmple of: Sondy Silt ond Cloy
From:PitlotSFcct
percent
Pct
I
,Comprcsslonupon
retting
\)
Moieture Cont¿nt - 23.3
Dry Density = 95
Somplc of: Sondy Silty Cloy
From:Pit2otSFcot
porccnt
pcf
N \
\
No movemenl
uPon
wettîng
0.1 1.0 100
HEPWORTH- PAWLAK
GEOTECHNICAL, INC.102 561 SWELL CONSOLIDAT1ON TEST RESULTS Fig. J
Moisturc Contcnt = 19.1
Dry Dcnsíty : 103
Somple of: Sondy Silty Cloy
From: Pit 2 of 7 Feel
percont
Pcf
No movcmont
upon
wctting
\
\
I t
lt
o
N
1c
.gg'üo
EL¿c
b()
3
4
t0
APPUED PRESSURE - ksf
0.1 r.0 100
102 561 HEPWORTH-PAWLAK
GEOTECHNICAL, INC.SWELL CONSOLÍDATION TEST RESULTS Fig. 4
HEPWORTH-PAWLAK GEOTECHNTCAL, rNcTABLE ISUMMARY OF LABORATORY TEST RESULTSJOß NO. l02'36Ìsor( o18€OnOCt TYFC_tsandy silt and claysandy silty claysandy silty claysandy silty clayI1,r¡COi¡f tNEOcoMPHfs!ilVÊsrntr¡ollttßsFtAIT€llcig L¡[¡llrs?t^5frcritocxl*l7UOU¡DUMtr{*t27scBctfifPÂSSlr|Of{o. 200srqvE8370GR^OAltOfisÂfiot3tG¡IÂVET¡*lf{AÍU8AtORYoft¡stfYlPcll1029995103ilATU¡IÀLi¡ü5runEcotttEt{ftat18.520.023.319.1s^MtrE rocÀÌrotto€Plfi¡f.rtI3557lìt12
rlrsPEcil0r Htt iloT BE ilnDE UlttES$
THIS GARII IS POSTEII OlI TIIE JOB
24 HOURS NOTTCE REQUIRED FOR TNSPECTIONS
*'
BUILDING PERMIT
ÊIRFIETD GOUIITY, COLONADO
Drtr
Addrt¡s tfl¡
Srth¡¡lrr
AGREEMENT
{,
Sid¿Slde Rclr
Tbis Crld Mocr Bc Pmtd So It ir Phioþ Visiblc From Ttr Struct U¡til Flnd Inrpcoior.
INSPECTION RECORI)
Footiug z
Found¡tion -r /l
UndcrAruund Plunbing 7t¡z Inaul¡tiou f7
Rongh Plumbing t ? -/ )d4-Itr1crll -'7â-D?r
Cbinncy& Vcnt t z,J><z*#-Eþctric Fir¡l(tv Sr¡rc t"ú,*t*itÁÌil#,
GrsPiping l Z.yt¿*f#Fill,l 1-yn ?*
Ebcfric Rogb (By strtc l¡¡Dccrorl¿r_ idW Scptic Final
Frrning
ffo lncludc Roof i¡ phcr
r¡d Doon lrlitdlcdl.
rnd rffi¡dow¡
Noter:
ALL LISTED ITEMS MI¡ST BE INSPECTED A¡$D APPROVED TEFORE COVERING -
IryHETHER INTER¡OR OR EXTEN,IOR, T'NDERGROTI¡ÍD OR AEOVE GROUIÍD.-
THIS PERIIIIT IS NOT TRANS¡trR.ABLE
Phone 3t{-5m3 t09 tth Strcct County Courthou¡c Gþnwood Springs, Color¡do.
APPROVEDD(} Nor DEsrRoY rHrs cARr)
*fiâaÐrt$¡4*W(g'-, I ' IF pLÁ,cED oursIDE - cbvnn wITH CLEAR pLAsrIc