HomeMy WebLinkAbout20090516.tiff • r� 1 HIGH PLAINS ENGINEERING & DESIGN, LLC
735 DENVER AVENUE, FORT LUPTON, CO 80621 • PHONE: (303) 857-9280 • FAX: (303) 857-9238
March 7, 2007
Mr. Wayne Harsh
Coyote Ridge Cluster P.U.D.
Hudson, CO 80642
RE: Preliminary Subsurface Analysis at Coyote Ridge Cluster P.U.D., Weld County,
CO.
Job # 06-1302
To Whom It May Concern:
One, four inch diameter hole was drilled to a depth of twenty five feet at the
Percolation # 1 site on February 23, 2007, as shown on the attached site map. Samples
of the soil were taken at two-foot intervals. These samples were analyzed in the field
and laboratory to determine the characteristics of the soil (per Unified Soil
Classification System) for identification and foundation design. In general, the soil
• profile in test hole # 1 indicated Sandy Silt (SM) to a depth of 7 feet, underlain by Sandy
Clay (SC) to a depth of 12 feet. Clay with Low Plasticity (CL) exists from 12 feet to 15
feet. Clay with Medium Plasticity exists from 15 feet to 25 feet. The Standard
Penetration Test similar to ASTM D1586 showed 8 blows for 12-inch penetration at a
depth of 4 feet, and 13 blows for a 12-inch penetration at a depth of 9 feet. Please
note that actual subsurface soil conditions may vary between samples and locations
tested.
One-dimensional swell/consolidation tests were performed on selected samples to
evaluate the expansive, compressive and collapsing nature of the soils and/or
bedrock strata. These tests indicated an expansion potential of 3.3% at a depth of 13
feet, and an expansion potential of 5.7% at a depth of 17 feet. The soils in this report
were classified using the American Society of Testing Materials (ASTM) procedures.
The geotechnical practice in State of Colorado utilizes a relative scale to evaluate
swelling (expansion) potentials. When a sample is wetted under a surcharge pressure
of 500 pounds per square foot (psf), the measured swell is classified as low, moderate,
high, or very high. The following table represents the relative classification criteria.
Please note that the measured swell is not the only criteria for slab-on-grade
recommendations and additional factors are considered by the engineer when
evaluating the risk for slab-on-grade construction.
• EXHIBIT
2009-0516 ID
•
TABLE I
SLAB PERFORMANCE REPRESENTATIVE
RISK CATEGORY PERCENT SWELL
(500 PSF SURCHARGE)
LOW 0 TO<3
MODERATE 3 TO<5
HIGH 5 TO<8
VERY HIGH ≥8
Source: Colorado Association of Geotechnical Engineers, Guideline for Slab Performance
Risk Evaluation and Residential Basement Floor System Recommendations (Denver
Metropolitan Area), 1996
Groundwater levels were not recorded at the time of our field investigation; however,
it may be possible for groundwater to exist at construction depths at a later date. The
groundwater can be expected to fluctuate throughout the year depending on
variations in precipitation, surface drainage and irrigation on the site. The possible
presence of shallow bedrock/dense clays beneath the surface is favorable for the
formation of "perched" groundwater. We recommend that the bottom of the
basement or crawlspace excavations be maintained at least 4 feet above the free
groundwater level.
Any ground water levels recorded represent the free, static water levels after
equalization of hydrostatic pressures in the test hole borings. It is possible that the
groundwater levels recorded in the test hole borings may not be present at those
levels in the foundation excavations. Flow rates, seepage paths, hydrostatic pressures,
seasonal groundwater fluctuations, water quality and other factors were not
determined in this investigation. A program, which may include special well
construction, test procedures, long-term monitoring program and analysis would be
necessary to determine these factors.
Our experience in the vicinity of the proposed Coyote Ridge Cluster P.U.D. indicates
that the potentially expansive clay will vary in depth from site to site. Each building will
require a site specific subsurface investigation to determine the type of foundation
required for the soil conditions.
•
• •
•
This project should be constructed by a qualified contractor with experience in similar
projects. The owner/builder is advised to observe and document the construction
process to ensure the construction is performed in accordance with the design
drawings and technical specifications.
This report does not address general hillside stability, landslide potential, and/or other
natural hazards. Several areas in the Colorado Front Range have known geologic
hazards associated with them. We recommend that readers of this report educate
themselves further as to the existence of geologic hazards on or around their specific
property of interest. The Colorado Geologic Survey {www.geosurvey.state.co.us or
303-866-2611} is a good source for publications (maps, reports, etc.) dealing with
specific geologic issues and/or issues related to specific geographic areas. The
foundation and retaining walls must be well cured and well braced prior to backfilling.
THE PARTIES SPECIFICALLY AGREE THAT HIGH PLAINS ENGINEERING & DESIGN, LLC HAS
NOT BEEN RETAINED NOR WILL THEY RENDER AN OPINION CONCERNING ANY
ENVIRONMENTAL ISSUES, HAZARDOUS WASTE OR ANY OTHER KNOWN OR UNKNOWN
CONDITIONS THAT MAY BE PRESENT ON SITE.•
NN Sincerely, r V°.CEGlS��4 r
7
Todd M. Schroeder, P.'‘ 73548 ct-f
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•
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Dlowcounts S)1 2 / 4 SANDY SILT(SM)
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Blcwcounts 13/12 // , 9
/ SANDY CLAY(SC)
/
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f✓//�/ CLAY WITH LOW PLASTICITY(CL)
1 4
IS
17
18
19
20 CLAY WITH MEDIUM PLASTICITY(CL)
21
22
23
4
2
/ 25
• SOIL PROFILE
• •
HIGH PLAINS ENGINEERING & DESIGN, LLC
735 DENVER AVENUE, FORT LUPTON, CO 80621 PHONE - (303) 857-9280 FAX - (303) 857-9238
• I2%
1O% — . .
��
6% r
-2% — -
-490 ADDED
-6%
-8% - 1
-1O% ,
100 5OO IOOO 20OO 3OOO 10000
GRAPH OF THIRTEEN FOOT DEPTH
X X S01L TYPE
nOLE I DEPTI1 L.L P.L. P.I. EXPANSION CON5OUDATION
- 29.32 20.06 9.26 3.3 CLAY MTh LOW PLASTICITY(CU
12%
t 1 I
1O%
' � I
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496 -_.__`_._.._--- -�. � __..�.� � --•--------------- -
2%
-2% H2O
ADDED
-4% 1 I
-6%
-8%
1O%
1OO 5OO IOOO 2OOO 3OOO 1OOOO
GRAPH OF SEVENTEEN FOOT DEPTH
X X 501L TYPE
ROLE I DEPM L.L. - P.L P.I. 4 EXPANSION CONSOLIDATION
• I IT 44 01 24.45 19.56 5.7 CLAY W TII MEDIUM PIA5TICJTY(CL)
JOB NO: 061302 JOB LOCATION:
OATS: 03102!07 COYOTE RIOGE CLUSTERPVD
DRAWN: Cluck A PORTION OP SECTION 26.T3N.R65W or DM CTn P.M.
CnECAW
WELD COUNTY,CT
SITE VAP
COYOTE RIDGE CLUSTER PUD
A PORTION OF SECTION R CO OF THE 6Th P.M.
WELD COUNTY,
O
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WINDMILL\ r
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t 32'
PERC #3 o
a
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°
540' S
a ° a
PERC #I —
slY ° 80' °
SOIL PROFILE a 0
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x
PERC #2
/ I-50
LEGEND
All locations shown above ore based on specific information
to-Percolation Test Hole furnished by others or estimates made In the field by High
Plains Engineering personnel. The locations, distances,
percolation Profile Hole directions, etc. are not the result of a property survey but
are approximations and are not warranted to be exact. It is
Soil Profile Hole the owner/builder's responsibility to define property -
boundaries and ensure all onsite improvements are located
X X-Fence within the platted site and out of inappropriate easements.
All distances are to be verfied prior to excavation.
Weld County Health Department 3/7/2007
• Percolation Test and Soils Data
"n HIGH PLAINS ENGINEERING 8t DESIGN, LLC
735 DENVER AVENUE, FORT LUPTON, CO 80621 • PHONE: (303) 857-9280 • FAX: (303) 857-9238
1;;4 ei 06-1302#2 I
rare„ fr COYOTE RIDGE CLUSTER PUD
Legal De3cfifitiati A PORTION OF SECTION 26, T3N, R65W OF THE 6TH P.M., WELD COUNTY, CO
Contact Information
Naive WAYNE HARSH
Street 22994 WCR 30
City,State,Zip HUDSON, CO 80642
Phone 303-536-9598, 303-619-3627 CELL
`r‘t...•x#e S YIIIWS._a. a -. .«.r, ,ailliil&aca.x`ai.a+;yyV4Q�11 emraC l`T tz37-N,ra . ., .. .
Sreeaied 4-=, rlcountered at I 71/2Jreet
He +i •YES ,
rid or Gr3d#ieT .>,a NO Estimated depth to mwuninm
IP
seasonal water table if not
Date and Thine 2/21/2007 pate encountered in.profile'
Presoak Water Added 12:00 time
Amount of Presoak Is area believed to be subject to
Water Added: 15 gallons seasonal fluctuations which could YES
Date and Time result in a seasonal water table within
Percolation Test 2/22/2007 date 8."oL.Surface?
Started: 12.30 time ; ,
Did Water Remain Ili Hole After the Overnight 2 ;-
Swelling Period? to this NORTHEAST'derectibit
Hole 1 YES
H)2 YES - K+p i,nS ...�.y�e '',#°'N'� a t�a '�.: MP,
Fl` nertr 3 YES gnter IGREATER THAN 8 (jet
I'M YES
S NO Estimated depth if not encountered in
NO profile:
Hofe 1 36 41.67 Type of Bedrock:I
Hole 2 36 35.71
H4l@ 3 36 35.71
Hie 4 36 35.71 Is bedrock fractured or weathered?
Hole 5 36 35.71
• Hole 6 36 35.71 Is bedrock believed to be permeable
Avenge 36.7 (perc rate <60 min/n)?
' LIMITING LAYER AT A DEPTH OF 5 FEET
• •
Weld County Health Department 3/712007
• Percolation Test and Soils Data
Note['Sgils rrfust be cletsified using unified system ASTM D2487
0
is A
-- 1
so
---2
u. 3 SANDY SILT(SM)
c
L --
fl
4 vi
p SANDY CLAY (SC)
- 5 4 LIMITING LAYER
s '
6
r....
7
CLAI(WITH MEDIUM PLASTICITY(CL)
• ---8it20
--
---10
I certify that the above information is correct and complete to the best of my knowledge and
that all tests were performed in the accordance with the provisions of Weld County Health
Department individual sewage disposal regulations by myself or under my supervision.
64 High Plains Engineering
Signature et & Design LLC
3354g I 735 Denver Avenue
13.N.3/7/c17 t� Ft. Lupton,CO 80621
et%.. 4 303-857-9280
• Date
• •
Si ft MAf'
COYOTE RIDGE CLUSTER PUD
A PORTION Of SECTION 2G, T3N,RG5W Of THE GTti P.M.
WELD COUNTY, CO
t
O
et
U
O
1-
WINDMILL
•
50'
4-32'
t'ERC #.3 � 0 0
°
0
0
0
540'
NOT TO SCALE
0 0 0
PERC #I
B0'
o a
0
a ° o
x o
f—so'
PERC #2
EGEND
All locations shown above are based on specific information
Percolation Test Hole furnished by others or estimates made in the field by High
Plains Engineering personnel. The locations, distances,
•colation Profile Hole directions, etc. are not the result of a property survey but
are approximations and are not warranted to be exact. It is
soil Profile Hole the owner/builder's responsibility to define property -
boundaries and ensure all onsite improvements are located
-Fence within the platted site and out of inappropriate easements.
All distances are to be verfied prior to excavation.
•
i • •
•plicant: E112 26-3-65
Planner: Case Number:
3 \ K. iIn________4_\I
35
/ 70 _ /1\73
72 \__
\ _./- /
70 9
\J72I
69
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\--A_ /
• 49 69 I _
i
70 !
69 7.
69
- \135 7
t 3 35
(-3,
\
Legend
- - Property Boundary' Lakes
- Highways Soil Types
Major roads Rail Road
• Local roads Floodplains
NStreams&Ditches
* Boundaries are estimated
• West Greeley Cons"tion District •
(970) 356-8097
Case Number:
Applicant: CoL/oTe r-tp(?C ?L
Planner:
Below is a list of the soils and their limitations according to the USDA, Weld County Soil Survey.
Map Shallow Dwellings Dwellings with Small Septic Tank Prime Farm Additional
Symbol Soil Name Soil Texture Excavations without basements Commercial Absorption Land (if Comments
basements Buildings Fields irrigated)
. 3IAquolls Gravelly Substratum Severe Severe Severe Severe Severe No
69 Valent Sand Severe Slight: siighl i:,ticifrt !?light No
70 Valent Sand Severe • iiglal: No
72 Vona Loamy Sands Slight Slight No
The West Greeley Conservation District recommends that the applicant does an on site soils test prior to any construction. For a more complete soils
description consult the Weld County Soil Survey or contact our office at (970) 356-8097, If you or the applicant have any questions please feel free
to call our office.
•
,U.�,ra 1.l.
t
Produced by the West Greeley Conservation District
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