HomeMy WebLinkAboutOWTS DesignSSGM
www.sgm-lnc.com
August L7,2022
Mr. Ted White, Environmental Health Specialist lll
Garfield County Public Health
2014 Blake Avenue
Glenwood Springs, CO 81601
RE:Krauth OWTS
L777 CR241.
East Elk Creek Road
New Castfe, CO 81647
Dear Ted,
The purpose of this letter is to provide you soils and design information relative to a tactile soils analysis that
SGM has performed on behalf of the Krauth family in support of the installation of an OWTS on the proposed soil
treatment areas located on their property located on their property up East Elk Creek in New Castle, Colorado.
The property in question sits on their ranch located atL777 CR24I, New Castle, Colorado. A specific address is
yet to be determined. The property parcel number is 2125-132-000-40. lt is located on shaded area in the
following figure:
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I l8 West Sixth St, Suite 200 | Glenwood Springs, CO 8.l601 | 970.945.1OO4
Page | 1
Phy¡lco¡ Add¡.!3 ì777 211 COUNTY RD
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GLENWOOD SPRINGS
OSGM
www.sgm-rnc.com
This report and design provides Mr. Krauth's conilactor, Kuersten Construction, the direction for which he can
construct an OWTS for the lot considering the development of an OWTS for the 3 bedroom cabin proposed. On
the drawings attached at the end of this report, you will see the necessary OWTS components for the described
sltuätlon.
To better acquaint you to the site, we have provided Figure 1 below page that is an image from the Google Earth
Much of the information discussed above is shown on Figure 1.
Fígure1-SiteLocation
From the NRCS Websoil Survey, the on-site soils (for the STA) are identified as a Torriothents Rock outcrop
complex. The on-site observations of the Torriothents loam were characteristic of the sandy loam identified in
the WebSoil Survey. We have attached a soil report from the NRCS Websoil Survey to describe further the
expected characteristics of the soils determined through our pre-site investigation. Our findings of the soil
concur with those characteristics identified by NRCS in their soil investigation for the Websoil information.
Specifically, our findings are as follows:
1. Depth to ground water is greater than 8 feet
'l l 8 West Sixth St, Suite 200 | Glenwood Springs, CO B 1 ó01 | 970.945.1 004
Page | 2
Proposed Cabin
East Elk Creek
GLENWOOD SPRINGS
øsGM
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3.
4.
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www.sgm-rnc.com
Depth to limiting layer (ie., ground water or bedrock) is 4 feet. Limiting layer is bedrock.
Other than a limited depth of topsoil, the soil horizon(s) below the topsoil is a consistent sandy loam soil
meeting the characteristics of the Soil Type 3A in Table 10-1 of Regulation 43 from CDPHE.
The soil structure grade was a moderate structure with approximately 50% peds found.
The No. LO sieve and smaller particles had a blocky/granular soil structure.
The sample contained less than 35% rock.
The ribbon size from tactile analysis revealed a 1to 2 inch ribbon with neither a gritty or smooth texture.
Given these results, the classification for these soils is a Sandy Loam, or as previously stated, a Type 3A
Soil per Regulation 43 Table 10-1. (GARCO Table 10-1)
The depth of this soil layer is 4 feet with no groundwater. However, bedrock is a limiting layer at the 48"
depth encountered.
The proposed OWTS for the cabin will consist of a 1,000 gallon septic tank (for 3 bedroom) discharging by gravity
flow from the second compartment to a 500 gallon dosing tank with an Orenco pump. From the dosing tank, the
supernatant will be pumped to an automatic distributing valve which will alternate flow between two 12' by 44'
mound systems. These facilities will be located on the south east slope below the proposed cabin. The mounds
will be pressure dosed with the distribution media being lnfiltrator Quick4 chambers. Under the chambers would
be a masonry sand of 30" depth to over lay at least 18" of native soils above bedrock. The system has been sized
for the Type 3 soils from a loading rate perspective.
The soil tactile analysis reveals a Type 3A soil which is reflective of percolation rates of 6I-75 mpi. The
loading rate for the Type 3A soil and TLl is 0.30 gallons/sf/day.
We are recommending constructing the STA in the Torriothents loam located just south and east of the
building site. This will accommodate a gravity system to the septic and dosing tanks. Because of the
geological constraints, the subsequent system will be pressure dosed to provide a uniform bio-mat for
adequate treatment per TL1.
Note that the drawing package is prepared in a semi-schematic format that relies on the contractor/owner to
provide adequate grading to accomplish the intent of the design. ln this manner, it is anticipated that the
contractor/owner can provide routing modifications to make sure that the grading works for the site.
Note that the component construction for the system will need to follow the requirements of Sections 43.8,43.9
and 43.10 of regulation 43 (as adopted by Garfield County) for the tank, dosing tank, pump, piping and STA as
applicable. We have attached a copy of each of these sections for reference by the contractor/owner to assure
each component construction is adequately addressed.
I l8 West Sixth St, Suite 200 | Glenwood Springs, CO 8l 601 t 970.945.1004
Page | 3
a
a
GLENWOOD SPRINGS
ESGM
Upon your receipt and review, if you have any questions, please don't hesitate to call.
Respectfu
S. Simonson, PE, CFM
Principal
www.sgm-rnc.com
I l8 West Sixth Sl, Suite 200 | Glenwood Springs, CO 81 6A1 | 970.945..l004
Page | 4
2Bt$2
8/7u22
GLENWOOD SPRINGS
Figure 2- Profile Hale #1
Soil Testing for
Dr. Lee Krauth OWTS
t777 CR241., East Elk Creek Road , New Castle, Colorado
Photo Documentation
Date:7/t4/2022
Figure J"A- Prafile llole #7 Spail Pile
Figure 2- Profile Hale #2 Figure 2A- Profile Hole f2
Figure 3- Profile Holes #7 and #2
19ñloFt4E ROSS. LCOMD@M,@LONOPRru EXISroG CONDITIONSSEC I 3, T5S, R9 IIV, 6TH P.¡4TBD COìNYROÐ 24I'iiPARTIAL EXISTING CONDITIONS SURVEYA PARCEL OF LAND SITUATED IN THE NW I/4 OF SECTION 13, TOWNSHIP 5 SOUTH, RANGE 91 WEST OF THE 6THPRINCIPAL MERIDIANCOUNTY OF GARFIELD, STATE OF COLORADOGWHC SCÀI¡ffiNEGWHC SCAEffi{r,E)-1 IleUs,,hÈ¡ }J V/_ /,\úlør'ú'rtur H.i)(,'\
1.0 Detailed Soil lnvestigation
This report only covers the tactile evaluation of soil samples collected during profiling appropriately
located on-site test pits. Visual evaluation for the profiling of the test pits is covered under a separate
report.
1.1 Tactile Evaluation
On 711412022 SGM conducted the soil textural by feel evaluation on two soil samples collected
during the visual evaluation of two on-site test pits.
The evaluation concluded for each soil sample:
1. Sample size = 1,000 ml.
2. Volume of rock > 35 mm (3/4") was 0 ml.
3. Volume of rock < 35 mm (314") > 2 mm (0.079) was 0 ml.
4. Total rock in sample = 0 ml.
5. Percent rock in sample = ÙVo.
Performing the soil texture by feel methodology on the non-rock portion of the sample TP-1
revealed:
The soiltexture by feel method using the CPOW SoilTexture Flow Chart was conducted on each
sample. Results are shown in the following table.
SAMPLE
Does Soil
Form a Ball
(yes/no)
Does Soil
Form a
Ribbon
fves/noì
*Type of Ribbon
Formed (Weak,
Moderate,
Stronoì
How Does the Soil Feel
(Gritty/Smooth/Neither)
TP-1 Yes Yes Strono Neither
TP-2 Yes Yes Stronq Neither
*Weak < 1 inch; Moderate 1-2 inches; Strong > 2 inches
Thc soil fclt ncithcr vcry smooth or gritty whcn cxccssivcly wcttcd, indicating a clay loam.
The soil shape for both samples was prismatic and the grade considered to be moderate. Using
these two soil characteristics with the finding of the soil texture by feel methodology indicates
this soil should be classified as soil type 3 with a long term acceptance rate (LTAR) of 0.35 for
level 1 treatment (TL-1).
gSGMso¡t PRoFttE lEil PtT toc{A SËPARAIÊ LOG SHAI.T. BE COMP¡trÎÊD FOR EACH SI'IL PROFAX TESTHTIpmpefty¡ø¡æ; 111.1 CF-. z*\ , |\l^t Ûlq(LL , ¿i2testPit¡'lumber: | à ?-oate*r.oedr€:3ktz¿Notlsl{t1--¿ I t"o & r-ùr'_..rfl &L.. trlbf^tr-*rþ t¡êß . lhltlng laycr as def,ned ln Rrtul.tlon G17? ÉVcs tr ttolf yer, desl¡n doarment must €xphln howtllË llmlfing condfrlon ls ¡ddressed.b Dãffion Arko3ê (DA) or cemêntod s¡nd (CSl present? tr yes ú ffolf yes, please answcr ttrc followlry:l¡ materlelfracturud and/orjot¡téd? El yes El NoWhdt ls thr cemeñtãdon das?ls the Dswson Arkosc or Cemcñtèd S¡ndllmltln!lâyrrpersÊctlo¡ s.7g,ZolùL7? O yes tr ¡loRldodrllorphlcHprtP!.¡.nt? tv/il,Soll'tIpttf.bb tO or'fSolblnT.bl.1$SoH SEUGh¡rÞGr¡d¡^/ lAuSDASof,lln¡st¡r¡ -fle.î>fSatctt\^I'.,r'tr ':,¿¡USOASoSlstur.îÞ(Sal I6** y'rpcs.r i a^4 I ¡..T"$.îpp ¿. I ix,u' {,7,, ¡Rrn¡r of Drptà olsollsüñc.0- A,á,." r* Å 6r,+ 4øn
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OWTS Design Report and Calculations
Project Locat¡onr Sestion
fownship
RangeNew Castle, CO 81647
Date: t41ul22
FIow Data foi the OWTS Design
1 Honìê Use (3 Bedroonr Honre)
TÕtâl=
Home Use 450 gpd 0.48 #/dây
Totals: 450 gpd 0.48 #/day
Soil Dâta for the OWTS
2 Data from on-site soil observãtions:
On site textural analysis reveals sandy loam
Berl rock encountered at a depth of 48" (4 feet).
Data from the web soil survey indicâtes a Toriorthints exists. Type 3A soil determined (for basal absorption area)
Average of 3 percolation holes: N/A mpi (Soil Tactile Analysis Perfomed)
6¡ven thê consideration of all data, the long Term Acceptânce Rate to us€ is 0.30 gallons/sf/dây
Septlc Tank Sí2¡ñg
Flow calculated from above: 450 gpd
48 hour detention t¡me for septic tank siz¡ng; Volume= 900 gpd
lnstall a 1,000 gallon tank for three bedrooms, 1250 for four bedrooms and 1500 gãllon tank for 5 bedrooms
Sizing of Absorption Field or Soil Treatment AÌea
4 Going with a soil type 3A and Treatment Level 1, LTAR =03 clstld
For a pressure dosed system, s¡ze adjustment factor is 1,0 for a bed conf¡gutâtion
For a gravity system, the s¡ze adjustment factor shall be 1.2 for a bed configuration
For a gravity trench system, adjustment fâctor = 1.0
For a pressure dosed trench system, adjustment factor = 0.8
For use of chambers: size adustmentfactor is 0.7
5TA= Flow/LTAR 1500 square feet (unfactored)
Client:Dr. Lee Krauth
L777 CR24l
Volume of Dose for Pump/Pressure Dlstrlbutlon Plpe Design
4 Dosing Tank Volumes and Pump Siz¡ng
13
5S
91W
450
450
For Home {Jse, 2 persons per bedroom and 75 gallons per day per person, BOD5 = 0.06 #/person/day
3
For a bed system, gravity flow, adjust size to 1.2*1500=
For a chamber system, grav¡ty flow, âdjust size to 0.7*1500-
lncorporsting ã pressurr dosêd trench syst€m, adjust slze to 0.8*1050=
Pressure dosed bed system using chambers, adjust to 0.8*1800=
For a chamber system in a bed conf¡gurat¡on, length=
Go wíth 2 beds in mound configuration leach 12x60)
With thê effectivc length of a Quick4 chamber at 4', use 45 chambers per bed for 2 beds
1800 square feet
1050 square feet
840 squãre feet
1440 square feet
120 feet (pressure dosed)
From dosing tank to the automat¡c distr¡buting valve, there will be 25 feet of 1" of Schedule 40 PVC
with a volume of 0.0705 gallons/ foot
Dra¡n back= 25 (0.0705) = 1.8 Gallons 1.7625
Maximum Dose Volume= 25% ofADF + Drain back
25%of ADF= 114.3 gâllons
Maximum Dose Volume= 114.3 gallons
Minimum Dose Volume= 4 times the lateral volume plus drain back
Lateralsare54feetlong(1"d¡ameter)x3perbedxlbed (installingautomaticdistribut¡ngvalve)
Man¡fold Length= 12 feet
Transport Line= 65 feet
Minimum Dose Volume= 72 gallons ¡n piping/per bed
Minimum Dose < Max¡mum Dose , thus okay
Using a 5oo tallon pre-cast dos¡nt tank, plan d¡mens¡ons are 4.33 feet x 4.33 feet
Area= 18.7 SF
7.4A*La.7/72= 11.7 gallons per inch ¡n tank
wlth maxlmum dose = 115 gallons, depth ¡n tank = 9,87 inches
With m¡nimum dose= 72 gallons, depth ¡n tank= 6.18 inches
27'
ReserveCapacity=42-29.74=72.26" (15"x11.7gallons/in)=
T¡me Dosing: Minimum Dose= 72 gallons
ADF= 450 gallons per day
Doses per day: 6 Doses per day
Pump¡ng at 9.2 gpm, thus,38/9.2= 1.93 min per dose
139 gallons
ALARM
PUMP ON
9.87"
9.87"
PUMPOFF :42"
SUMMARY:
60Use Orenco PF1005 Head Effluent
Go wlth 1000 gallon pre cast
Usê orenco v4403 Automatic Distributing Valve
l(t i',fil,[ffi,Ënn'Tn;*"'
An Employee Orned Compony
5020 County Road 154
Glenwood Springs, CO 81601
phonc: (970) 945-7988
t?x: (970) 945-8454
email : kaglenwood(lkumarusa.com
www.knmarusa. com
Office Louations: Dcnvcr (HQ), P¿rker, Cok¡ratlo Springs, Fort Collins, Glcnwoud Springs, aud Sumurit Corurty, Colorado
April19,2022
4 ET, LLC
c/o John Kuersten
PO Box 1530
13 Powerline Road
Rifle, CO 81650
lon
Project No.22-7-164
Subject: Subsoil Study for Foundation Design, Proposed Cabin, West of 1777 County
Road 241, East Elk Creek Road, Garfield County, Colorado
Gentlemen:
As requested, Kumar & Associates, Inc. performed a subsoil study for design of foundations at
the subject site. The study was conducted in accordance with our proposal for geotechnical
engineering services to 4 ET, LLC dated February 3,2022. The data obtained and our
recommendations based on the proposed construction and subsurface conditions encountered are
presented in this report.
Proposed Construction: The proposed cabin will be a two-story wood-framed structure located
in the general vicinity of the borings shown on Figure 1. Ground floor will be slab-on-grade or
structural over crawlspace. Cut depths are expected to range between about 3 to 5 feet.
Foundation loadings for this type of construction are assumed to be relatively light and typical of
the proposed type ofconstruction.
If building conditions or foundation loadings are significantly different from those described
above, we should be notified to re-evaluate the recommendations presented in this report.
Site Conditions: The project site is currently vacant. There is an existing two-track driveway
that accesses the proposed building site. Topography at the site is hilltop with variable slopes
generally down to the northwest and southeast. Vegetation at the site consists of native grass and
weeds with scattered sagebrush, scrub oak, and juniper trees.
Field Exploration: Thc ficld cxploration for thc projcct was conductcd on April 4, 2022. Two
exploratory borings were drilled at the locations shown on Figure 1 to evaluate the subsurface
conditions. The borings were advanced with 4-inch diameter continuous flight augers powered
by a truck-mounted CME-458 drill rig. The borings were logged by a representative of Kumar
& Associates, Inc.
Samples of the subsuils were laken with l%-inch antl 2-inuh I.D. spuun sarnplers. Tlte suttplers
were driven into the subsurface materials at various depths with blows from a 140-pound
-2-
hammer falling 30 inches. This test is similar to the standard penetration test described by
ASTM Method D-1586. The penetration resistance values are an indication of the relative
density or consistency of the subsoils and hardness of the bedrock. Depths at which the samples
were taken and the penetration resistance values are shown on the Logs of Exploratory Borings,
Figure 2. The samples were returned to our laboratory for review by the project engineer and
testing.
Subsurface Conditions: Graphic logs of the subsurface conditions encountered at the site are
shown on Figure 2. The subsoils consist of about I to 2 feet of silty sand with gravel overlying
siltstone/sandstone bedrock of the Maroon Formation. Drilling in the bedrock with auger
equipment was difficult due to the hardness and drilling refusal was encountered in the deposit at
depths of l6 and 6 feet in Borings I and2, respectively.
Laboratory testing performed on samples obtained from the borings included natural moisture
content and density and percent finerthan sand size gradation analyses. The laboratory testing is
summarized in Table 1.
No free water was encountered in the borings at the time of drilling and the subsurface materials
were slightly moist to moist.
Foundation Recommendations: Considering the subsurface conditions encountered in the
exploratory borings and the nature of the proposed construction, we recommend spread footings
placed on the undisturbed natural bedrock designed for an allowable bearing pressure of
3,000 psf for support of the proposed cabin. Footings should be a minimum width of 16 inches
for continuous walls and2 feet for columns. Loose and disturbed soils and existing road fill
encountered at the foundation bearing level within the excavation should be removed and the
footing bearing level extended down to the undisturbed natural bedrock. Exterior footings
should be provided with adequate cover above their bearing elevations for frost protection.
Placement of footings at least 36 inches below the exterior grade is typically used in this area.
Continuous foundation walls should be reinforced top and bottom to span local anomalies such
as by assuming an unsupported length of at least 10 feet. Foundation walls acting as retaining
structures should be designed to resist a lateral earth pressure based on an equivalent fluid unit
weight of at least 45 pcf for the on-site soil as backfill.
Floor Slabs: The natural on-site soils and bedrock, exclusive of topsoil, are suitable to support
lightly loaded slab-on-grade construction. To reduce the effects of some differential movemento
floor slabs should be separated from all bearing walls and columns with expansion joints which
allow unrestrained vertical movement. Floor slab control 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 minimum 4 inch
layer of free-draining gravel should be placed beneath basement level slabs to facilitate drainage.
Kumar & Associates, Inc. @ Project No. 22-7-164
a-J
This matcrial should consist of minus 2-inch aggregate with less than 50Yo passing the No. 4
sieve and less than 2%o passing the No. 200 sieve.
All fill materials for support of floor slabs should be compacted to at least95%;o of maximum
standard Proctor density at a moisture content near optimurn. Required fill can consist of the on-
site soils devoid of vegetation, topsoil and oversized rock.
Underdrain System: Although free water was not encountered during our exploration, it has
been our experience in the area and where bedrock is shallow that local perched groundwater can
develop during times of heavy precipitation or seasonal runoff. Frozen ground during spring
runoff can create a perched condition. We recommend below-grade construction, such as
retaining walls, crawlspace and basement areas, be protected from wetting and.hydrostatic
pressure buildup by an underdrain system.
The drains should consist of drainpipe placed in the boffom of the wall backfill surrounded above
the invert level with free-draining granular material. The drain should be placed at each level of
excavation and at least 1 foot below lowest adjacent finish grade and sloped at a minimum lYoto
a suitable gravity outlet. Free-draining granular material used in the underdrain system should
contain less than 2Yo passingthe No. 200 sieve, less than 507o passing the No. 4 sieve and have a
maximum size of 2 inches. The drain gravel backfill should be at least IYzfeetdeep and covered
with filter fabric such as Mirafi 140N.
Surface Drainage: The following drainage precautions should be observed during construction
and maintained at all times after the cabin has been completed:
1) Inundation ofthe foundation excavations and underslab areas should be avoided
during construction.
2) Exterior backfill should be adjusted to near optimum moisture and compacted to
at least 95%o of the maximum standard Proctor densiff in pavement and slab areas
and to at least 90Yo of the maximum standard Proctor density in landscape areas.
Free-draining wall backfill should be capped with about 2 feet of the on-site, finer
graded soils to reduce surface water infiltration.
3) The ground surface surrounding the exterior of the building should be sloped to
drain away from the foundation in all direotions. We recommend a minimum
slope of 6 inches in the first 10 feet in unpaved areas and a minimum slope of
3 inches in the frrst l0 fèet in pavement and walkway areas.
4) Roof downspouts and drains should discharge well beyond the limits of all
backfill.
Limitations: 'lhis study has been conducted in accordance with generally accepted geotechnical
engineering principles and practices in this area at this time. We make no warranty either
express or implied. The conclusions and recommendations submitted in this report are based
Kumar & Associates, Inc. @ Project No. 22-7-164
-4-
upon the data obtained from the exploratory borings drilled at the locations indicated on Figure I
and to the depths shown on Figure 2,theproposed t¡pe of construction, and our experience in
the area. Our services do not include determining the presence, prevention or possibility of mold
or other biological cont¿minants (MOBC) developing in the future. If the client is concerned
about MOBC, then a professional in this special field of practice should be consulted. Our
findings include interpolation and extrapolation of the subsurface conditions identified at the
exploratory borings and variations in the subsurface conditions may not become evident until
excavation is performed. If conditions encounterd during construction appear different from
those described in this rqnr! we should be notified at once so re-evaluation of the
recommendations may be made.
This report has been prepared for the exclusive use by our client for design pu{poses. We are not
responsible for technical interpretations by others of our information. As the project evolves, we
should provide continued consultation and field services during construction to review and
monitor the implønentation of our recommendations, and to veri$r that the recommendations
have been appropriately interpreted. Significant design changes may require additional analysis
or modifications ûo the recommendations presented herein. We recommend on-site observation
of excavations and foundation bearing strata and testing of structural fill by a representative of
the gætechnical engineer.
If you have any questions or if we may be of further assistance, please let us know.
Respectfu lly Submitted,
Kumar & Associates, Iüc"
Robert L. Duran, P.E.
Reviewedby:
Steven L. Pawlak, P.E.
RLDlkac
attachments Figure I - Location of Exploratory Borings
Figure 2 - Logs of Exploratory Borings
Figure 3 - Legend and Notes
Table I - Summary of Laboratory Test Results
Kumar & Associates, lnc. ('Project No, 22-7-164
Fl¡JULIl¡JJ()U)Ul-xorv.fL(L0? t9F-z.:)Fo+(J C\NOi\<ño-EoF1rlI,c'=Ê,o@oi. ,/7Haoþ4cts¡9-.---'l$(oI|.\INNU,o(uc)oaDooð(uE=Ytn(9z.É.omÉ.oFÉ.oJo-xt¡Jl!oz.oF()oJO)l!t0-r9
P
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I
BORING 1
EL.6156'
BORING 2
EL. 6t 56'
0 0
37 /6, 50/ 4.5
WC=3.6
DD=122
44/ 12
\NC=7.7
DD= 1 30
-2OO=54
5 50/2.5 5so/6
WC=2.5
DD=127
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20 20
22-7-164 Kumar & Associates LOGS OF EXPLORATORY BORINGS Fig. 2
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SAND (SM) STLTY TO VERY S|LTY, WITH GRAVEL, LOOSE TO MEDTUM DENSE,
MOIST, RED.
WEATHERED SILTSTONE/SANDSTONE, MEDIUM HARD, MOIST, RED, SLIGHTLY
CALCAREOUS.
SANDSTONE/SILTSTONE, VERY HARD, SLIGHTLY MOIST, RED, CEMENTED
DRIVE SAMPLE, 2-INCH I.D. CALIFORNIA LINER SAMPLE.
DRIVE SAMPLE, 1 3/8-|NCH t.D. SpLrT SPOON STANDARD PENEIRAT|ON TEST
aa/1, DRTVE SAMPLE BLOW COUNT. |ND|CATES THAT 44 BLOWS OF A 140-P0UND HAMMER",.- FALLING 30 INCHES WERE REQUIRED TO DRIVE THE SAMPLER I2 INCHES.
I PRACTICAL AUGER REFUSAL.
NOTES
1. THE EXPLORATORY BORINGS WERE DRILLED ON APRIL 4, 2022 WITH A 4-INCH-DIAMETER
CONTINUOUS-FLIGHT POWER AUGER.
2. TI1E LOCATIONS OF THE EXPLORATORY BORINGS WERE MEASURED APPROXIMATELY BY PACING
FROM FEAÏURES SHOWN ON THE SITE PLAN PROVIDED.
3. THE ELEVATIONS OF THE EXPLORATORY BORINGS WERE OBTAINED BY INTERPOLATION BETWEEN
CONTOURS ON THE SITE PLAN PROVIDED.
4. THE EXPLORATORY BORING LOCATIONS AND ELEVATIONS SHOULD BE CONSIDERED ACCURATE
ONLY TO THE DEGREE IMPLIED BY THE METHOD USED.
5. THE LINES BETWEEN MATERIALS SHOWN ON THE EXPLORATORY BORING LOGS REPRESENT THE
APPROXIMATE BOUNDARIES BETWEEN MATERIAL TYPES AND THE TRANSITIONS MAY BE GRADUAL.
6. GROUNDWATER WAS NOT ENCOUNTERED IN THE BORINGS AT THE TIME OF DRILLING.
7. LABORATORY TEST RESULTS:
WC = WATER CONTENT (%) (ASTM D2216);
DD = DRY DENSITY (pcf) (ASTM D2216);
-200= PERCENTAGE PASSING NO. 200 SIEVE (ASTM D1140).
22-7 -164 Kumar & Associates LEGEND AND NOTES Fig. 3
I (+rt i;ffil,*ffifffif '"'ån' **'TABLE 1SUMMARY OF LABORATORY TEST RESULTSNo.22-7164SOIL TYPESiltstone/SandstoneSiltstone/SandstoneWeathered SiltstonelpsflUNCONFINEDCOMPRESSIVESTRENGTHP/"1PLASTICINDÐ(ATTERBERG LIMITSlo/"1LISUID LIMITPERCENTPASSING NO.200 stEvE54SANDl'lùGRADATIONtf/"|GRAVEL127130NATURALDRYDENSITYlocfl1227.7lololNATURALMOISÏURECONTENT3.62.5ItfiìDEPTH2Y25SAMPLE LOCATIONBORINGI2
USDA United States
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Natural
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Custom Soil Resouree
Report for
Rifle Area, Golorado,
Parts of Garfield and
Mesa Counties
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Preface
Soil surveys contain information that affects land use planning in survey areas.
They highlight soil limitations that afiect 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 ofücials, 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 localgovernments may impose
special restrictions on land use or land treatment. Soil surveys identiff 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
identiffing and complying with existing laws and regulations.
Although soil survey information can be used for generalfarm, 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/nrcs/main/soils/health/) 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://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/?
cid=nrcs1 42p2_053951 ),
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, colo¡ nationalorigin, age, disability,
and where applicable, sex, marital status, familial status, parential status, religion,
sexual orientation, genetic information, political beliefs, reprisal, or because all or a
part of an individual's ingome 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 USDAs TARGET Center at(2O2)720-2600 (voice
and TDD). To file a complaint of discrimination, write to USDA, Director, Office of
Clvll Rlghte, l400lndependenee Avenuê, S.W., Waehington, D.C. 20250-9410 or
call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity
provider and employer.
3
Contents
Preface...,.,.
SoilMap.....
SoilMap (Krauth).
Legend............
Map Unit Legend (Krauth).......
Map Unit Descriptions (Krauth).......
Rifle Area, Colorado, Parts of Garfield and Mesa Counties......
ô7-Torriorthents-Rock outcrop complex, steep...........
Soil lnformation for All Uses.
SoilReports.
Soil Physical Properties
Engineering Properties (Krauth).......,.....
References
.2
.5
..6
..7
.9
.9
11
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13
13
13
17
4
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
dlsplayed on the map, Also presented are various metâdata about data used to
produce the map, and a description of each soil map unit.
5
3i.3 Custom Soil Resource Report
SoilMap (Krauth)
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Custom Soil Resource ReportMAP LEGENDiIAP INFORMATIONThe soil survelrs that comprise your AOI were mapped at1:24,000.Please rely on the bar scale on eacfi map stæet br mapmeasurements.Source of Map: Natufãl Resources Conservation ServiceWeb Soil Survey URL:Coordinate System: Web Mercator (EPSG:3857)Maps from the Web Soil Suruey are based on the Web Merc¡torprojection, wh¡ch preserves dircc-tion and shape but distortsdistance and area. A pojedion that pr€serves area, sucfi as theAlbers equal-area conic projection, should be used if morcaccurate calculations of distance or area are requircd.This poduct is generated from the USDA-NRCS certifed datia asof the version date(s) listed below.Soil Survey Area: Rifle Area, Colorado, Pa¡ts of Garfield andMesa CountiesSurvey Area Data: Version'l4,Sep 2, 2021Soil map unib are labeled (as space allows) for map scales1:50,000 or larger.Date(s) aerial images were photographed: Aug 25, 2021-Sep5,2021The orhophoto or other base map on which the soil lines werecorpiled and digitized probably difiers ftom the backgroundAÞa of Intr]lrl (AOl)SollrAr6a of lntÊr€st (AOl)Soil Map Unit Pol!€on8ã Spoil Arsad SbnyspotI V6ryStonySpotS wotspotß Other.t. Sp€cial Line Featur€sYUÍor FêåtulrrSfeams and CanalsTrrn!poñstlon4+4 Rails.'4 lntar8t¡at€ Highways** USRout€s,.. Major Roads. Local RoedsBeckgroundI Asriel Photogrâplryæ Soil Map Unit Lin€gI Soil Map Unit PoinbSp.cld Polnt F.åtun .(Ð BlowoutEl Bor¡ow Pit* Clay Spot0 Closed DepressionX Gravel Pitj, Gravolly Spotü LãndfillÅ" Lava Flow{b Maßhorswempfit M¡neorQuarrye Miscellaneous\itfaterI Perennial Water1,n Rock Outcmp+ Saline Spot:.: sandyspot€l Severcly Eroded Spotô Sinkholeþ Slide or Slipø Sodicspot7Waming: Soil Map may not be valid at this scale.Enlargement of mape beyond the scale of mapping can ceuaemisunderctanding of th€ detail of mapping and accuracy of soill¡ne placêment. The meps do not shor the small areas ofcontrasting soils that could have been shot rn at a more deÞiledscale.
Gustom Soil Resource ReportMAP LEGËNDMAP INFORMANONimagery displayed on these maps. As a result, somè minorofunit boundarieseúident.I
Custom Soil Resource Report
Map Unit Legend (Krauth)
Map Unit Descriptions (Krauth)
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 properties 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
particular 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
gerrelally are in suull 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 all the soils and
miscellaneous areas on the landscape.
ïhe presence of minor components in a map unit in no way diminishes the
usefulness or accurâcy 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,
onsite investigation is needed to define and locate the soils and miscellaneous
areas.
I
Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI
67 Torriorthents-Rock outcrop
complex, steep
1_0 10O.Oo/"
Totals for Area of lnterest 1.0 100.0%
Custom Soil Resource Report
An identifying symbol precedes the map unit name in the map unit descriptions.
Each description includes generalfacts about the unit and gives important soil
properties and qualities.
Soils that have profiles that are almost alike make up a soil 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 into soi/ 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 assocr,afi'on 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
G7-Torriorthents-Rock outcrop com pl ex, steep
Map Unit Setting
Nationalmap unit symbol: jnz5
Elevation: 5,800 to 8,500 feet
Mean annual precipitation: 10 to 15 inches
Mean annual air temperafure; 39 to 46 degrees F
Ftost-free period: 80 to 105 days
Farmland classification' Not prime farmland
Map Unit Composition
Toniorthents, steep, and similar soils:60 percent
Rock outcrop, sfeep.'25 percent
Esûmafes are based on obseruations, descriptions, and transects of the mapunit.
Description of Torriorthents, Steep
Setting
Landform : Mountainsides
Landform position (two-dimensional); Footslope
Landform posítion (three-dimensional) : Mountainflank, base slope
Down-slope shape: Concave, convex
Across-s/ope shape : Concave, convex
Parent matenaf Stony, basaltic alluvium derived from sandstone and shale
Typicalprofile
Hl - 0 to 4 inches: variable
H2 - 4 to 30 inches: fine sandy loam
H3 - 30 to 34 inches: unweathered bedrock
Properties and qualities
S/ope: 15 to 70 percent
Depth to restrictive feature:4 to 30 inches to lithic bedrock
Dninage c/ass; Well drained
Runoff class; High
Çapacíty of the mo.sf limíting layer to transmit water (Ksat): Moderafely low to
moderately high (0.06 to 0.20 in/hQ
Depth to water table: More than 80 inches
Frequency of f/ooding: None
F req ue ncy of pondrng: None
Calcium carbonate, maximum content:5 percent
Maximum salinity: Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm)
Available water supply, 0 to 60 inches: Very low (about 2.4 inches)
lnterpretive groups
Land capability cl assification (irrigated) : None specified
Land capability cl a ssification (noni nigated) : 7 e
Hydrologic Soil Group: D
Hydric so/ rafing: No
Description of Rock Outcrop, $teep
Setting
Landform: Mountainsides
11
Custom Soil Resource Report
Landform position (three-dimensional) : Free face
Down-slope shape: Convex
Across-s/ope shape : Convex
Typicalprofile
H1 - 0 to 60 inches; unweathered bedrock
Properties and qualities
S/ope; 15 to 70 percent
Depth to restrictive feature:0 inches to paralithic bedrock
Runoff class; Very high
Capacity of the most limiting layer to transmit water (Ksat); Very low to moderately
high (0.00 to 0.20 in/hr)
Available water supply, 0 to 60 inches: Very low (about 0.0 inches)
lnterpretive groups
Land capabil ity classifrcation (irrigated) : None specified
Land capability classification (noninigated): 8s
Hydríc soi/ rafing: No
12
Soil lnformation 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 descrlptlon 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.
Engineering Properties (Krauth)
lh¡s table grves the engineering classitications and the range ot engrneenng
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://
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 vidually 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
13
Custom Soil Resource Report
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 8. 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. Ïhese 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
soilthat is7 to27 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."
Ctassification 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, SR 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 classifies 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, orA-7-6. As an additional
refinement, the suitability of a soil as subgrade material can be indicated by a group
14
Custom Soil Resource Report
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 identifo the expected
Low (L), Representative Value (R), and High (H).
Percentage (of soil particlesj passrng designated sieyes 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 index (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 identif,
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-OO.
15
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:i/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).Engineering Properties-Rifle Area, Golorado, Parts of Garfield and Mesa GountiesPlasticity indexL.R.HNP-10-20LiquidlimitL-R.H15-25-35o-7 -14Percentage passing sieve number-200L.R-H2548-7040L-R-H50-65-80t0L-R-H60-90-904L-R-H65-95-95Pct Fragments3-10inchesL.R.H0-10- 200- 6- 20>10inchesL.R.H0-0-00-0-0GlassificationAASHTOA-2,A,4,A-6UnifiedsM, sc-sM, cL-ML, CLUSDA texturcVariableFine sandy loam,loam, clay loamUnweatheredbedrockUnweatheredbedrockDepthlno-44-3030-340-60Hydrolog¡cgroupDPct. ofmapunit6025Map unit symbol andsoil name67*Toniorthents-Rockoutcrop complex,steepToniorthents, steepRock outcrop, steepl6
References
American Association of State Highway and Transportation Ofücials (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-OO.
Cowardin, L.M., V. Cartet F.C. Golet, and E.T. LaRoe. 1979. Classification of
wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife
Service FWS/OBS-79/3 1 .
Federal Register. July 13, 1994. Changes in hydric soils of the United States.
Federal Register. September 18,2002. Hydric soils of the United States.
Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric
soils in the United States.
National Research Council. 1995. Wetlands: Characteristics and boundaries.
SoilSurvey Division Staff. 1993. Soilsurvey manual. SoilConservation Service.
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18
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