HomeMy WebLinkAboutSPRING CREEK RANCH - PDP - 14-05 - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTROCK CLASSIFICATION
(Based on ASTNI C-24.4)
Sedimentary Rocks
Sedimentary rucks are stratified materials laid down by water or wind, The, sediments may be
composed of particles or pre-existing rocks derived by Mechanical auaalherinq, -evaporation or by
t
chen;it;21 or or origin.. The stidiments are usually indurated by comentation or compaction.
Chert
Very fine-grained siliceous ro& composed of micro, -crystalline or cryptocrystalline
'
quartz, chalcedony or opal. Chart is various colored, porous to dense, hard and
has a c:oncholdal to splintery fracture.
Claystone
Fine -gained rock composed of or derNed by erosion of silts and clays or any rock
'
containing clay. Soft massi*va and may confain carbonate minerals.
Cotiglomarate
Rack consisting of a considerable .amount of rounded graval, sand and cobbles
'
with or without interstitial or cementing material. The cementing or interstitial
matodal naafi+ be quarry, capal, calcite, dolomite, cAy, iron oxides or other
materials_
'
Dolomite
A fine-grained carbonate rock consisting of the mineral dolomite [CaMg(CG )2],
May contain non -carbonate intppelles such as quartz, .chart, clay ;minerals,
organic matter, gypsum and sulfides. Reacts with hydrochloric acid (HCL).
'
Urnestonne
A fine-grained carbonate rock consisting of the mineral calcite+ (Caco_3}. May
contain non -carbonate imps rdfes such as quartz, chart, clay minerals, organic
'
matter, gypsum and sulfides. Reacts with hydrochloric acid (HCL),
Sandstone
Bock consisting of particles of sand with or without interstitial and cementing
materials. The cementing or interstitial material may be quartz, opal, calcite,
'
dolornite, clay, iruh oxides or other rnaieriai,
Spate
Fine-grained rock ooniposed o 'or derived by erasion of silts and days or"any rock
giant rning 'elay `Shale is "hard, peaky;`, of fissile may -tie gray" bl�afc; re dish of "
'
green and may contain sonata carborimat minerals (calcareoirs shalej.
Siftstone
Fine grained mck con p6 d of or derived by 'erosion of nits qr rock eontaenntg-
silt.: SlItstones consisl predomin- ant of silt sized particles IQ 0625.to Q.d02 mm1n
..
diameter}g anare in ermediate nicks botv&6n claystones and; aarf sMn tes and..
inaycoatairi s..aroonate:mine�als: '` _
, ..,
3
1
...
rt4 r
UNIFIED SOIL CLASSIFICATION SYSTEM
Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests*
Soil Classification
Group
'
Symbol
Group Name°
Coarse Grained Soils
Gravels
Clean Gravels
Cu z 4 and 1 s Cc s 3°
GW
Well -graded gravel`
More than 50% retained
More than 50% of coarse
Less than 5% fines`
Cu <4 and/or 1 > Cc> 3`
GP
Poorly
fraction retained on
graded gravel`
on No. 200 sieve
No. 4 sieve
Gravels with Fines More Fines classify as ML or MH
GM
Silty gravel r.`."
than 12%fines`
Fines classify as CL or CH
GC
Clayey gravel`.°"
Sands
Clean Sands
Cu z 6 and 1 s Cc s 3E
SW
Well -graded sand'
50% or more of coarse
Less than 5%fines°
Cu <6 and/or 1 > Cc > 3°
SP
Poorly sand'
fraction passes
graded
No. 4 sieve
Sands with Fines
Fines classify as ML or MH
SM
Silly sand°.".'
More than 12% fines°
Fines Classify as CL or CH
SC
Clayey sand`"'
Fine -Grained Soils
Silts and Clays
inorganic
PI > 7 and plots on or above'A" line'
CL
Lean day""
'
50% or more passes the
Liquid limit less than 50
No. 200 sieve
pl <4 or plots below "A" line'
ML
Silt'C1'
organic
Liquid limit - oven dried
Organicclaylmx
<0.75
OL
Liquid limit - not dried
Organic silt'�" -O
Silts and Clays
inorganic
PI plots on or above 'A' line
CH
Fat clay"O
'
Liquid limit 50 or more
PI lots below "A' line
MH
Elastic Silt ,"
organic
Liquid limit - oven dried
Organic clay" P
<0.75
OH
Liquid limit -not dried
Organic silt"O
Highly organic soils
Primarily organic matter, dark in
color, and organic odor
PT
Peat
Abased on the material passing the 3-in. (75-mm) sieve
e If field sample contained cobbles or boulders, or both, add "with cobbles
or boulders, or both" to group name.
°Gravels with 5 to 12% fines require dual symbols: GW-GM well -graded
gravel with silt, GW-GC well -graded gravel with clay, GP -GM poorly
graded gravel with silt, GP -GC poorly graded gravel with day.
°Sands with 5 to 12% fines require dual symbols: SW-SM well -graded
sand with silt, SW -SC well -graded sand with Gay, SP-SM poorly graded
sand with silt, SP-SC poorly graded sand with clay
z
ECu = Dco/Dro Cc= (Dao)
Dio x Do
`If soil contains >_ 15% sand, add "with sand" to group name.
°If fines classify as CL-ML, use dual symbol GC -GM, or SC-SM.
60
50
a
w 40
O
Z
H 30
U
g 20
a
10
7
4
0
' Fonn 111--659
t I I 1
For classification of fine-grained
soils and fine-grained fraction
_of coarse -grained soils
Equation of 'A" - fine
Horizontal at PI-4 to LL=255.
— then P1=0.73 (LL-20) — —
Equation of "tY - line
vertical at LL=16 to PI=7,
— then P1=0.9 (LL-6) --- ��--
'v
ML or OIL
I
"If fines are organic, add 'with organic fines" to group name.
If soil contains z 15% gravel, add "with gravel" to group name
' If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay.
Klf soil contains 15 to 29% plus No. 200, add "with sand" or'with
gravel," whichever is predominant.
`If soil contains >_ 30% plus No. 200 predominantly sand, add
"sandy" to group name.
ulf soil contains z 30% plus No. 200, predominantly gravel, add
"gravelly" to group name.
"PI >_ 4 and plots on or above "A" line.
°PI <4 or plots below "A" line.
°PI plots on or above "A" line.
°PI plots below "A" line.
MH or OH
0 10 16 20 30 40 50 60 70 so 90 100 110
LIQUID LIMIT (LL)
Irerracon
' GENERAL NOTES
D RI LLING & SAMPLING SYMBOLS:
' Ss: split §Poore . 1.116' I.P., 2" U.t?., tzrtigss othevoilge n7tei -is: Hollow Steer AtQur
;yT: Thin-1'@atlad Tuba? - 2' 0.0 unless otherrrise noted PA: Power Ricer
RS: RiN Sumpiur= 2,42" 1.0, ;i 0.0., Unlr-gsr t4aSrwi",ea noted HA-- Hand Auger
' OU: dizar,ond Bit Coring - d", 14, B RB: Flock fait
a&- Bulk Sample or Axvor Sample We: Wash Bates or Mud Pbt ary
Teo-- n;xrksr of blows required to otvori;e a S4+ntl;xi0 2-inch O.C. sptit-spoon saampter [SS] the last 12 inches of the total 18-inch
penulr31i0.? with a 140-pound hammer falling 30 inches is considered the "Standard Penetration' or `tN-value-". For J," O.D. ring
ataiplers (RS) the pane-tration value is resorted as the number Gt bbms rcrquin;d to advanct, the gompF -,r 7:� Inches using 9 14¢-pound
hammer falling 30 intvs, repuftd its `bairn Our 00l; and ig not c nsidered equx+aletvto the "Standard Penetratior."or'14-value".
APPENDIX C
lrprr.mirnn
No Text
60
50
CL CH
P
L
A
40
S
T
I
C
T
30
Y
I
N
20
m01
D
E
X
10
A
ML
MH
CL-ML
20
40 60 80 100
LIQUID LIMIT
Specimen Identification
LL
PL
PI
%Fines
Classification
•
1
9.0ft
NP
NP
NP
14
SILTY SAND with GRAVEL(SM)
m
2
4.0ft
35
14
21
70
SANDY LEAN CLAY
A
9
9.0ft
26
12
14
43
CLAYEY SAND(SC)
Irerracon
ATTERBERG LIMITS RESULTS
Project: Proposed Multi Family Development
Site: S of Drake Rd. and E of Taft Hill Rd. Fort Collins, Colorado
Job #: 20055046
Date: 4-4-05
it
IS
31M
.1 ME
U.1
APPLIED PRESSURE, TSF
10
Specimen Identification
Classification
Ya, pcf
WC,%
191
10 4.Oft
SANDY LEAN CLAY
109
12
Notes:
z CONSOLIDATION TEST
a
Project: Proposed Multi Family Development
z Irerracon Site: S of Drake Rd. and E of Taft Hill Rd. Fort Collins, Colorado
o Job #: 20055046
U
o Date: 4-4-05
1
fl
Ii
IME
y:
3S
V.I
APPLIED PRESSURE, TSF
10
Specimen Identification
Classification
Yd, pcf
WC,%
101
9 4.Oft
SANDY LEAN CLAY
112
6
Notes:
a
CONSOLIDATION TEST
Project: Proposed Multi Family Development
Irerraccin Site: S of Drake Rd. and E of Taft Hill Rd. Fort Collins, Colorado
o Job #: 20055046
U
Date: 4-4-05
11
Ii
Ii
111
1l'
1
1
APPLIED PRESSURE, TSF
Specimen Identification
Classification
Yd, pcf
WC,%
101
8 4.Oft
1 CLAYEY SAND
104
3
Notes:
z CONSOLIDATION TEST
a
Project: Proposed Multi Family Development
zSite: S of Drake Rd. and E of Taft Hill Rd. Fort Collins, Colorado
Irerraccin
o Job #: 20055046
U
Date: 4-4-05
-4
-2
00
U)
M
m
r 2
r
0
n
O
z
O
r
4
a
0
z
6
8
10
0.1 1 10
APPLIED PRESSURE, TSF
N
Q
e
0
J
Notes:
Z
0
U
'a
U'
v
0
N
N
O
O
z
CONSOLIDATION TEST
a
Project: Proposed Multi Family Development
zIrerracon
Site: S of Drake Rd. and E of Taft Hill Rd. Fort Collins, Colorado
o
Job #: 20055046
U
Date: 4-4-05
Specimen Iden tification
Classification
Yd, pcf
WC,%
•
4 9.Oft
CLAYEY SAND
114
18
-4
-2
M
m
r 2
r
C)
O
z
U)
O
r
4
a
0
z
6
8
10
0.1 1 10
APPLIED PRESSURE, TSF
N
P
r
0
0
N
Specimen Identification
Notes:
z
0
U
'a
U'
<d
v
0
N
N
O
O
z CONSOLIDATION TEST
a
Project: Proposed Multi Family Development
NIrerracon
Site: S of Drake Rd. and E of Taft Hill Rd. Fort Collins, Colorado
o Job #: 20055046
U
Date: 4-4-05
Classification Yd, pcf WC,%
• 4 4.Oft SILTY SAND 108 2
-4
-2
00
r 2
r
O
O
z
O
r
°y 4
0
z
6
8
10
0.1 1 10
APPLIED PRESSURE, TSF
N
e
P
H
N Notes:
Z
O
U
'a
e
a
0
N
N
O
O
a
CONSOLIDATION TEST
Project: Proposed Multi Family Development
Irerracon
Site: S of Drake Rd. and E of Taft Hill Rd. Fort Collins, Colorado
o
Job #: 20055046
U
F
Date: 4-4-05
Specimen Identification
Classification
Yd, pcf
WC,%
•
3 9.Oft
SANDY LEAN CLAY
124
7
1
11
IS
Ni
AMS
�i
U.1
APPLIED PRESSURE, TSF
10
Specimen Identification
I Classification
I Y" pcf
WC,%
101
2 9.Oft
1 WEATHERED BEDROCK SILTSTONEI CLAYSTONE
1 108
19
Notes:
z CONSOLIDATION TEST
a
Project: Proposed Multi Family Development
N Site: S of Drake Rd. and E of Taft Hill Rd. Fort Collins, Colorado
Irerraccin
o Job #: 20055046
U
Date: 4-4-05
U)
rn
m
r
r
0
(7
O
z
U)
0
r
O
1
O
z
H
Iwo
IS
y�
U.I
1
APPLIED PRESSURE. TSF
10
Specimen Identification
Classification
Yd, pcf
WC,%
•
2 4.Oft
SANDY LEAN CLAY
102
25
Notes:
a
CONSOLIDATION TEST
Project: Proposed Multi Family Development
Irerracon Site: S of Drake Rd. and E of Taft Hill Rd. Fort Collins, Colorado
o Job #: 20055046
U
Date: 4-4-05
m
r
r
O
z
Cn
O
r
a
0
z
11
RZ
3:
.1i
U
a
APPLIED PRESSURE, TSF
10
Specimen Identification
I Classification
'Yd, pcf
WC,%
•
1 19.0ft
I BEDROCK: SILTSTONE/ CLAY! TONE
124
13
Notes:
z CONSOLIDATION TEST
a
Project: Proposed Multi Family Development
Irerracon Site: S of Drake Rd. and E of Taft Hill Rd. Fort Collins, Colorado
o Job #: 20055046
U
Date: 4-4-05
-4
-2
0111
Cn
M
m
r
r 2
0
n
O
z
N
O
r
4
D
O
z
6
8
10
0.1 1 10
APPLIED PRESSURE, TSF
N
0
N
Specimen Identification
Classification
Yd, pcf
WC,%
4.0ft
SANDY LEAN CLAY
120
14
No Text
LOG OF BORING NO. 10
Page 1 of 1
CLIENT
ENGINEER
Spring Creek Ranch, LLC
SITE S of Drake Rd. and E of Taft Hill Rd.
PROJECT
Fort Collins, Colorado
Proposed Multi Family Development
SAMPLES
TESTS
DESCRIPTION
m
}
w
L)
_
m
0
x
?�
��
Z
Z
OZ
o�
U
2
LL,
U
r0
¢z
>_
V�
0
Approx. Surface Elev.: 5084 ft
o
Z)
z
It
ai m
C)
o a
D v,
—' `
0.5 6"TOPSOIL 5083.5
SANDY LEAN CLAY
Brown, reddish brown, calcareous, stiff
3 5081
CLAYEY SAND
Reddish brown, loose to medium dense,
SC
1
CS
12
14
10.7
107
1665
trace gravel
5
' Silty sand with gravel lenses encountered
Sc
2
SS
12
12
1 7.4
10
SC
3
SS
12
6
24.3
15
SC
4
SS
12
16
12.2
20
25 5059
25
SC
5
CS
NR
4
BOTTOM OF BORING
The stratification lines represent the approximate boundary lines
between soil and rock types: in -situ, the transition may be gradual.
WATER LEVEL OBSERVATIONS, ft
Irerracon
BORING STARTED 3-11-05
WL
� 22 WD
= DCI 21.4 AB
RING COMPLETED3 1-05
WL
�
�
RIG
CMG
WL
Water Level on 3/15/2005
APPROVED DAR
I JOB # 20055046
LOG OF BORING NO. 9
Page 1 of 1
CLIENT
ENGINEER
Spring Creek Ranch, LLC
SITE S of Drake Rd. and E of Taft Hill Rd.
PROJECT
Fort Collins, Colorado
Proposed Multi amil Development
SAMPLES
TESTS
VO
J
DESCRIPTION
J
m
>
i
o
p n
W
Z�
3z
W
r Z
V
Cn
m
WEL
z�
H
�
�Z
OF4t
V7
0
W
V
�W
VZ
W
�
a
Approx. Surface Elev.: 5082 ft
o
D
z
ff
C8 m
� o
o a
U)
11 a o
—'
0.5 6"TOPSOIL 5081.5
CLAYEY SAND
Brown, reddish brown, calcareous, loose to
medium dense
CL
1
CS
12
12
5.9
112
5
Silty sand with gravel lenses encountered
26/12/43
CL
2
SS
12
7
10.9
10
15 5067
15
CL
3
SS
12
8
13.6
BOTTOM OF BORING
The stratification lines represent the approximate boundary lines
between soil and rock types: in -situ, the transition may be gradual.
WATER LEVEL OBSERVATIONS, ft
BORING STARTED 3-11-05
WL
s DRY WD
=DRY ABElrearacon
COME-75EFDOREMAN 3BOMPLET1-05
WLIY-
R GRING
CMG
WL
Water Level on 3/15/2005
APPROVED DAR
JOB # 20055046
LOG OF BORING NO. 8
Page 1 of 1
CLIENT
ENGINEER
Spring Creek Ranch, LLC
SITE S of Drake Rd. and E of Taft Hill Rd.
PROJECT
Fort Collins, Colorado
Proposed Multi amil Development
SAMPLES
TESTS
DESCRIPTION
J
m
i
w
a
=
�
�
m
cU
OZ
a
a-
L)
W
FO
WZ
>_
W
Approx. Surface Elev.: 5086 ft
o
z
vi in
< °
o a
0.5 6"TOPSOIL 5085.5
SANDY LEAN CLAY
CL
1
SS
12
11
15.8
/P///////
Brown, reddish brown, calcareous, stiff
3 5083
CLAYEY SAND
Reddish brown, loose to medium dense,
Sc
2
CS
12
22
3.2
104
trace gravel
5
Silty sand with gravel lenses encountered
SC
3
CS
12
8
11.0
110
10
15 5071
15
SC
4
SS
12
25
7.6
BOTTOM OF BORING
The stratification lines represent the approximate boundary lines
between soil and rock types: in -situ, the transition may be gradual.
WATER LEVEL OBSERVATIONdAB
��rracon
BORING STARTED 3-11-05
WL
Q DRY WD
=DRY
1-05
COME75EDFOREMAN 3
WL
�
YWL
RGRING
CMG
Water Level on 3/15/2
APPROVED DAR
JOB # 20055046
LOG OF BORING NO. 7
Page 1 of 1
CLIENT
ENGINEER
Spring Creek Ranch, LLC
SITE S of Drake Rd. and E of Taft Hill Rd.
PROJECT
Fort Collins, Colorado
Proposed Multi amil Development
SAMPLES
TESTS
DESCRIPTION
M
�
z a
pd
w
U
U)
�W
�
Zm
ULuw>W
C)
Approx. Surface Elev.: 5090 ft
0
D
z
r
w
of
a°0
U) m
a
3: 0
W
0 a
zlr
Z) U)
' `
0.5 6"TOPSOIL 5089.5
CL
1
SS
12
6
18.9
1.5 SANDY LEAN CLAY 5088.5
Brown reddish brown calcareous stiff
SILTY SAND WITH GRAVEL
Reddish brown, medium dense
SM
2
RS
12
38
4.6
5
6 5084
SANDY LEAN CLAY
Brown, reddish brown, calcareous, stiff
CL
3
SS
12
10
14.1
10
15 5075
15
CL
4
SS
12
11
17.3
BOTTOM OF BORING
The stratification lines represent the approximate boundary lines
between soil and rock types: in -situ, the transition may be gradual.
WATER LEVEL OBSERVATIONS=AB
BORING STARTED 3-15-05
WL
� DRY WD
� DCI 11a�on
5-05
COME75EDFOREMAN 3
WL
�
YWL
RGRING
CMG
Water Level on 3/16/20APPROVED
DAR
I JOB # 20055046
LOG OF BORING NO. 6
Page 1 of 1
CLIENT
ENGINEER
Spring Creek Ranch, LLC
SITE S of Drake Rd. and E of Taft Hill Rd.
PROJECT
Fort Collins, Colorado
Proposed Multi amil Development
SAMPLES
TESTS
o
DESCRIPTION
m
i
e
o
U
a
Z-'
U)m
0�
��
�
Z
ZZ
Q
U
a
U
iiW
p
aZ�U
0W
Approx. Surface Elev.: 5095 ft
o
D
z
Ofa�
ui m
U
o
Z)U)o
= `
0.5 6"TTOPSOIL 5094.5
SANDY LEAN CLAY
Brown, reddish brown, calcareous, medium
stiff to very stiff
CL
1
IRS
12
7
19.6
100
5
CL
2
SS
12
13
9.1
10
12 5083
SILTY SAND WITH GRAVEL
Reddish brown, medium dense
15 5080
15
SM
3
SS
12
25
4.0
BOTTOM OF BORING
* 3 inch diameter and 10 feet in length PVC
casing installed
The stratification lines represent the approximate boundary lines
between soil and rock types: in -situ, the transition may be gradual.
WATER LEVEL OBSERVATIONS, ft
lrearracon
BORING STARTED 3-15-05
WL
DRY WD
1 DCI 12 AB
3 5-05
BORING COME
WL
IWL
7-
RIG 75EFDOREMAN
CMG
Water Level on 3/16/2005
APPROVED DAR
JOB # 20055046
LOG OF BORING NO. 5 Page 1 of 1
CLIENT ENGINEER
Spring Creek Ranch, LLC
SITE S of Drake Rd. and E of Taft Hill Rd. PROJECT
Fort Collins, Colorado
(7
DESCRIPTION
aU
Q
Approx. Surface Elev.: 5085 ft
0.5 6"TOPSOIL
SANDY LEAN CLAY
Brown, reddish brown, calcareous, stiff to
very stiff
SILTY SAND WITH GRAVEL
Reddish brown, medium dense
BOTTOM OF BORING
Proposed Multi Family Developme
SAMPLES
TESTS
J
O
r
�n
m
>
5
w
x
z�
Ztn
KQ�Zt1
LL
ZUUZp
N
m
Z}a U
�
ZrofaZ)
m
U
a
zO
5084.5
CL
1
SS
12
8
18.1
—I CL 1 2 IRS 12 1 17 1 11.1 1 119 1 1
—ICL1 3 ISSI 12 1 7 112.41 1 1
10
5073
T
5070 SC
15
12 1 20 110.6
The stratification lines represent the approximate boundary lines
between soil and rock types: in -situ, the transition may be gradual.
WATER LEVEL OBSERVATIONS, ft BORING STARTED 3-15-05
WL DRY WD = 13 AB Irerracon RIG BORING COMPLETED CME-75OREMAN 3 CMG
5-05
WL Water Level on 3/16/2005 APPROVED DAR I JOB # 20055046
LOG OF BORING NO. 4
Pagel of 1
CLIENT
ENGINEER
Spring Creek Ranch, LLC
SITE S of Drake Rd. and E of Taft Hill Rd.
PROJECT
Fort Collins, Colorado
Proposed Multi amil Develo ment
SAMPLES
TESTS
DESCRIPTION
m
r5
w
U
1
F
z
U)
m
W
p
?�
�f_
�
0W
0
Approx. Surface Elev.: 5077 ft
w
ai
w
a�
a0
W^
z�
0 `
0.5 6"TTOPSOIL 5076.5
SANDY LEAN CLAY
2 Brown, reddish brown, medium stiff, 5075
calcareous
SILTY SAND
Reddish brown, medium dense
SM
1
CS
12
22
2.5
108
5
6 5071
rx
CLAYEY SAND
reddish brown, loose, trace gravel
SC
2
CS
12
8
17.3
109
850
10
15 5062
15
SC
3
SS
12
5
20.5
BOTTOM OF BORING
The stratification lines represent the approximate boundary lines
between soil and rock types: in -situ, the transition may be gradual.
WATER LEVEL OBSERVATIONS, ft
BORING STARTED 3-1175
WL
� DRY WD
1 DCI 13.8 AB
1-05
COME-75EDFOREMAN 3
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APPROVED DAR
I JOB # 20055046
LOG OF BORING NO. 3
Page 1 of 1
CLIENT
ENGINEER
Spring Creek Ranch, LLC
SITE S of Drake Rd. and E of Taft Hill Rd.
PROJECT
Fort Collins, Colorado
Proposed Multi amil Development
SAMPLES
TESTS
UDESCRIPTION
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BOTTOM OF BORING
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between soil and rock types: in -situ, the transition may be gradual.
WATER LEVEL OBSERVATIONS, ft
BORING STARTED 3-11-05
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APPROVED DAR
I JOB # 20055046
LOG OF BORING NO. 2 Page 1 of 1
CLIENT
Spring Creek Ranch, LLC
ENGINEER
SITE S of Drake Rd. and E of Taft Hill Rd.
Fort Collins, Colorado
PROJECT
Proposed Multi amil Development
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DESCRIPTION
Approx. Surface Elev.: 5068 ft
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5043.5
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124.5
BOTTOM OF BORING
3 inch diameter and 10 feet in length PVC
casing installed
The stratification lines represent the approximate boundary lines
between soil and rock types: in -situ, the transition may be gradual.
WATER LEVEL OBSERVATIONS, ft
Irerracon
BORING STARTED 3-11-05
WL
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1 5.6 AB
RING COMPLETED3 1-05
WL
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CMG
WL
Water Level on 3/15/2005
APPROVED DAR
I JOB # 20055046
LOG OF BORING NO. 1 Page 1 of 1
CLIENT
Spring Creek Ranch, LLC
ENGINEER
SITE S of Drake Rd. and E of Taft Hill Rd.
Fort Collins, Colorado
PROJECT
Proposed Multi Family Development
(�
U_
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(D
DESCRIPTION
Approx. Surface Elev.: 5075 ft
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TESTS
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8 5067
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1605
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12 5063
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WEATHERED 1
SILTSTONE/CLAYSTONE
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16 5059
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Olive gray, rust, hard to very hard
24.8 5050
5
SS
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13.0
BOTTOM OF BORING
3 inch diameter and 10 feet in length PVC
casing installed
The stratification lines represent the approximate boundary lines
between soil and rock types: in -situ, the transition may be gradual.
WATER LEVEL OBSERVATIONS, ft
BORING STARTED 3-11-05
WL
V DRY WD
IT 12.8 AB
3 1-05
COME
BOMPLETIrerracon
WL
R GRING
75EFDOREMAN
CMG
WL
Water Level on 3/15/2005
APPROVED DAR
JOB # 20055046
1
DRAKE ROAD
A A
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V11
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I
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---- ---- 1 l ---- I 10 i
— — — — — — uucc srRa�T —
ll�l FIGURE 1: TEST BORING LOCATION DIAGRAM
LEGEND SPRING CREEK RANCH
SOUTH OF DRAKE ROAD AND SPRING CREEK, AND EAST OF TAFT HILL ROAD
APPROX. TEST BORING LOCATIONS FORT COLLINS, COLORADO
Project Wgr DAR Project No.
1r`A rr�con Scale: 20055046
Designed By:
1 "=120'
Checked By: Date:
DAR 301 N. Howes Street Date:
Approved By: Fort Collins, Colorado 80521 Drawn By:
DIAGRAM IS FOR GENERAL LOCATION ONLY, DAR DJS
AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES. File Name: 20055046-1 100705 Figure No.
— 1
.... . .��m
Geotechnical Engineering Report llierraoon
Spring Creek Ranch - 88-Unit Multi -Family Development
' South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
' engineering practices. No warranties, either express or implied, are intended or made. Site
safety, excavation support, and dewatering requirements are the responsibility of others. In the
' event that changes in the nature, design, or location of the project as outlined in this report are
planned, the conclusions and recommendations contained in this report shall not be considered
valid unless Terracon reviews the changes and either verifies or modifies the conclusions of this
report in writing.
20
Geotechnical Engineering Report lferracon
Spring Creek Ranch - 88-Unit Multi -Family Development
' South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
' Surface Drainage
' Positive drainage should be provided during construction and maintained throughout the
life of each structure on the site. Infiltration of water into utility or foundation excavations
must be prevented during construction. Planters and other surface features, which could
retain water in areas adjacent to the building or pavements, should be sealed or
eliminated. In areas where sidewalks or paving do not immediately adjoin the structure,
we recommend that protective slopes be provided with a minimum grade of approximately
' 10-percent for at least 10 feet from perimeter walls. Backfill against footings, exterior
walls, and in utility and sprinkler line trenches should be well compacted and free of all
construction debris to reduce the possibility of moisture infiltration.
' Downspouts, roof drains or scuppers should discharge into splash blocks or extensions
when the ground surface beneath such features is not protected by exterior slabs or
paving. Sprinkler systems should not be installed within 10-feet of foundation walls.
Landscaped irrigation adjacent to the foundation system should be minimized or
' eliminated.
GENERAL COMMENTS
Terracon should be retained to review the final design plans and specifications so comments can
be made regarding interpretation and implementation of our geotechnical recommendations in the
' design and specifications. Terracon also should be retained to provide testing and observation
during excavation, grading, foundation and construction phases of the project.
The analysis and recommendations presented in this report are based upon the data obtained
from the borings performed at the indicated locations and from other information discussed in this
report. This report does not reflect variations that may occur between borings, across the site, or
' due to the modifying effects of weather. The nature and extent of such variations may not
become evident until during or after construction. If variations appear, we should be immediately
notified so that further evaluation and supplemental recommendations can be provided.
' The scope of services for this project does not include either specifically or by implication any
' environmental or biological (e.g., mold, fungi, bacteria) assessment of the site or identification or
prevention of pollutants, hazardous materials or conditions. If the owner is concerned about the
potential for such contamination or pollution, other studies should be undertaken.
This report has been prepared for the exclusive use of our client for specific application to the
project discussed and has been prepared in accordance with generally accepted geotechnical
19
Geotechnical Engineering Report 1rerracon
Spring Creek Ranch - 88-Unit Multi -Family Development
South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
Additional Design and Construction Considerations
Exterior Slab Design and Construction
Compacted subgrade or existing clay soils will expand with increasing moisture content;
therefore, exterior concrete grade slabs may heave, resulting in cracking or vertical
offsets. The potential for damage would be greatest where exterior slabs are constructed
adjacent to the building or other structural elements. To reduce the potential for damage,
we recommend:
• exterior slabs be supported on fill with no, or very low expansion potential
• strict moisture -density control during placement of subgrade fills
• placement of effective control joints on relatively close centers and
isolation joints between slabs and other structural elements
• provision for adequate drainage in areas adjoining the slabs
• use of designs which allow vertical movement between the exterior slabs
and adjoining structural elements
In those locations where movement of exterior slabs cannot be tolerated or must be
reduced, consideration should be given to:
• Constructing slabs with a stem or key -edge, a minimum of 6 inches in
width and at least 12 inches below grade;
• supporting keys or stems on drilled piers; or
• providing structural exterior slabs supported on foundations similar to the
building.
Underground Utility Systems
All piping should be adequately bedded for proper load distribution. It is suggested that
clean, graded gravel compacted to 75 percent of Relative Density ASTM D4253 be used
as bedding. Utility trenches should be excavated on safe and stable slopes in accordance
with OSHA regulations as discussed above. Backfill should consist of the on -site soils or
imported material approved by the geotechnical engineer. The pipe backfill should be
compacted to a minimum of 95 percent of Standard Proctor Density ASTM D698.
18
Geotechnical Engineering Report lrerracon
Spring Creek Ranch - 88-Unit Multi -Family Development
' South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
Liquid Limit.................................................................................. 30 (max)
• Plasticity Index............................................................................. 15 (max)
GroupIndex................................................................................. 10 (max)
Engineered fill should be placed and compacted in horizontal lifts, using equipment and
procedures that will produce recommended moisture contents and densities throughout
the lift. It is recommended all fill material to placed on the site be compacted to at least
95 percent of Standard Proctor Density ASTM D698.
On -site clay soils should be compacted within a moisture content range of 1 percent
below, to 3 percent above optimum. Imported granular soils should be compacted within a
moisture range of 3 percent below to 3 percent above optimum unless modified by the
project geotechnical engineer.
• Excavation and Trench Construction
. Excavations into the on -site soils will encounter a variety of conditions. Excavations into
the clays can be expected to stand on relatively steep temporary slopes during
' construction. However, caving soils and groundwater may also be encountered. The
individual contractor(s) should be made responsible for designing and constructing stable,
temporary excavations as required to maintain stability of both the excavation sides and
' bottom. All excavations should be sloped or shored in the interest of safety following local
and federal regulations, including current OSHA excavation and trench safety standards.
The soils to be penetrated by the proposed excavations may vary significantly across the
site. The preliminary soil classifications are based solely on the materials encountered in
' widely spaced exploratory test borings. The contractor should verify that similar conditions
exist throughout the proposed area of excavation. If different subsurface conditions are
encountered at the time of construction, the actual conditions should be evaluated to
determine any excavation modifications necessary to maintain safe conditions.
As a safety measure, it is recommended that all vehicles and soil piles be kept to a
' minimum lateral distance from the crest of the slope equal to no less than the slope height.
The exposed slope face should be protected against the elements.
17
' Geotechnical Engineering Report 1(erraoon
Spring Creek Ranch - 88-Unit Multi -Family Development
South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
' Exposed areas, which will receive fill, once properly cleared and benched where
necessary, should be scarified to a minimum depth of 12-inches, conditioned to near
optimum moisture content, and compacted.
It is anticipated that excavations for the proposed construction can be accomplished with
' conventional earthmoving equipment.
Based upon the subsurface conditions determined from the geotechnical exploration, the
' majority of the underlying subgrade soils exposed during construction are anticipated to be
relatively stable; however soft compressible and/or unstable areas will be encountered
during construction in close proximity to groundwater, or where the cohesive soils have a
high moisture content. The stability of the subgrade may be affected by precipitation,
repetitive construction traffic or other factors. If unstable conditions develop, workability
may be improved by scarifying and drying. Overexcavation of wet zones and replacement
' with granular materials may be necessary. Use of lime, fly ash, kiln dust, cement or
geotextiles could also be considered as a stabilization technique. Laboratory evaluation is
recommended to determine the effect of chemical stabilization on subgrade soils prior to
construction. Lightweight excavation equipment may be required to reduce subgrade
pumping.
' Subgrade Preparation
Subgrade soils beneath interior and exterior slabs, should be scarified; moisture
conditioned and compacted to a minimum depth of 12-inches below proposed controlled
fill material. The moisture content and compaction of subgrade soils should be maintained
until slab or pavement construction.
Fill Materials and Placement
' Approved imported materials may be used as fill material and are suitable for use as
compacted fill beneath interior or exterior floor slabs.
' Imported soils (if required) should conform to the following:
' Percent finer by weight
Gradation (ASTM C136)
...................................................................................................... . 100
' No. 4 Sieve..................................................................................... 50-100
No. 200 Sieve.............................................................................. 35 (max)
16
Geotechnical Engineering Report 1rerracon
Spring Creek Ranch - 88-Unit Multi -Family Development
' South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
' investment for pavements. Prior to implementing any maintenance, additional engineering
observation is recommended to determine the type and extent of preventive maintenance.
Site grading is generally accomplished early in the construction phase. However as construction
proceeds, the subgrade may be disturbed due to utility excavations, construction traffic,
' desiccation, or rainfall. As a result, the pavement subgrade may not be suitable for pavement
construction and corrective action will be required. The subgrade should be carefully evaluated at
the time of pavement construction for signs of disturbance or excessive rutting. If disturbance has
occurred, pavement subgrade areas should be reworked, moisture conditioned, and properly
compacted to the recommendations in this report immediately prior to paving.
Please note that if during or after placement of the stabilization or initial lift of pavement, the area
is observed to be yielding under vehicle traffic or construction equipment, it is recommended that
Terracon be contacted for additional alternative methods of stabilization, or a change in the
' pavement section.
Earthwork
General Considerations
' The following presents recommendations for site preparation, excavation, subgrade
preparation and placement of engineered fills on the project.
' All earthwork on the project should be observed and evaluated by Terracon. The
evaluation of earthwork should include observation and testing of engineered fill, subgrade
preparation, foundation bearing soils, and other geotechnical conditions exposed during
the construction of the project.
' Site Preparation
Strip and remove any existing debris or other deleterious materials from proposed building
' and pavement areas. All exposed surfaces should be free of mounds and depressions
that could prevent uniform compaction.
After the required overexcavation is performed, the site should be initially graded to create
a relatively level surface to receive fill, and to provide for a relatively uniform thickness of
fill beneath proposed building addition.
15
Geotechnical Engineering Report lrerramn
Spring Creek Ranch - 88-Unit Multi -Family Development
' South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
base course. Aggregate base course should be placed in lifts not exceeding six inches and
should be compacted to a minimum of 95% Standard Proctor Density (ASTM D698).
Asphalt concrete pavement should be composed of a mixture of aggregate, filler, binders, and
additives, if required, and approved bituminous material in accordance with the LCUASS
Pavement Design Criteria. The asphalt concrete should conform to an approved mix design
' stating the Hveem and/or Superpave properties, optimum asphalt content, job mix formula and
recommended mixing and placing temperatures. Aggregate used in the asphalt concrete should
' meet particular gradations, such as the Colorado Department of Transportation Grading S, SX or
SG specifications. Mix designs should be submitted prior to construction to verify their adequacy.
Asphalt material should be placed in maximum 3-inch lifts and should be compacted to a within a
range of 92 to 96 % of Maximum Theoretical Density.
Long-term pavement performance will be dependent upon several factors, including maintaining
subgrade moisture levels and providing for preventive maintenance. The following
recommendations should be considered the minimum:
' Site grading at a minimum 2% grade away from the pavements;
• The subgrade and the pavement surface have a minimum % inch per foot slope to promote
proper surface drainage.
• Consider appropriate edge drainage and pavement under drain systems,
• Install pavement drainage surrounding areas anticipated for frequent wetting (e.g. garden
' centers, wash racks)
• Install joint sealant and seal cracks immediately,
• Seal all landscaped areas in, or adjacent to pavements to minimize or prevent moisture
' migration to subgrade soils;
• Placing compacted, low permeability backfill against the exterior side of curb and gutter;
' and,
• Placing curb, gutter and/or sidewalk directly on subgrade soils without the use of base
course materials.
' Preventive maintenance should be planned and provided for through an on -going pavement
management program. Preventive maintenance activities are intended to slow the rate of
' pavement deterioration, and to preserve the pavement investment. Preventive maintenance
consists of both localized maintenance (e.g. crack and joint sealing and patching) and global
maintenance (e.g. surface sealing). Preventive maintenance is usually the first priority when
' implementing a planned pavement maintenance program and provides the highest return on
14
Geotechnical Engineering Report
Spring Creek Ranch - 88-Unit Multi -Family Development
South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
lferracon
Recommended alternatives for flexible and rigid pavements, summarized for the automobile
parking and heavy duty/truck access drives are as follows:
TraffcrArea
E
"AliematrvesAsphalt
' RECOMMENDE
,tMINIMUM`PAVEMEN,T4THICKNESS
Asphalt Concrete
Aggregate Base
INCHES CDOT�DESIGN
i2tFlyAsh
P�olan
u
Concrete Surfaced
= Surface Gratlmg
CourseCtass
Treated Sub
Cement
Total
#''"
O
GradmgrSX orS��S
'T..en eY , .{
•. or SG
�, a�4 3s�
s 5 or 6
w'o Y�''v}"
Base
Concretes
#�3.5,.,, cS3i.r.
\Y`e2'1':. k✓� "
ir.0� .�-�"2:. •"� �"'�
a.£
{. fiHoN,yii
A
1.5
2.0
6.0
9.5
Automobile
Parking
B
1.5
2.0
6.0
12.0
21.5
c
12.0
5.0
17.0
Heavy
A
1.5
2.0
7.0
10.5
Duty/High
Traffic Volume
B
1.5
2.0
6.0
12.0
21.5
Areas
c
12.0
6.0
18.0
(1) If the asphalt surface course is to consist of Grading S, then the required minimum
' lift/thickness placed should be 2-inches. If the asphalt surface course is to consist of Grading
SX, the required minimum lift/thickness placed should be 1-1/2-inches.
' (2) If fly ash is utilized for the on -site pavement improvement areas to mitigate the soft
compressible soils, it is recommended that at least the upper 12-inches of the prepared
subgrade be treated with fly ash. Using a minimum thickness of 12-inches of fly ash treated
subgrade will reduce the required asphalt thickness by approximately 1 to 1-1/2-inches.
However, in most cases the required minimum asphalt pavement thicknesses take precedent
in the pavement thickness sections. Therefore no reduction is provided and the use of fly ash
is incorporated into the pavement design and construction procedures to mitigate the unstable
subgrade soils only. Terracon is available to provide the required laboratory soil and fly ash
' mix design as well as placement recommendations upon request.
(3) Alternative A assumes a proof -rolled and approved subgrade section has been achieved.
' Due to the properties of the existing cohesive on -site soils, full depth asphalt pavement is
not recommended.
' Each alternative should be investigated with respect to current material availability and economic
conditions. Aggregate base course (if used on the site) should consist of a blend of sand and
gravel, which meets strict specifications for quality and gradation. Use of materials meeting
' Colorado Department of Transportation (CDOT) Class 5 or 6 specifications is recommended for
1
13
Geotechnical Engineering Report lrerracon
Spring Creek Ranch - 88-Unit Multi -Family Development
South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
' Pavement Design and Construction
' The subsoils at or near anticipated pavement subgrade levels, generally consisted of slightly
plastic, cohesive soils, exhibiting low to moderate subgrade strength characteristics, non -to low
swell/expansive potential, generally less than 2 percent, which would typically require a swell
' mitigation plan. However, depending upon the time of year for construction and the presence of
high moisture contents in the soils, it may be necessary to stabilize the pavement subgrade prior
to placement of base course or Hot Mix Asphalt (HMA) materials.
' If subgrade stabilization is necessary, two subgrade stabilization alternatives are presented
herein, which include either over -excavating and re -moisture conditioning to near optimum
moisture content and recompacting to 95 percent of Standard Proctor Density ASTM D698 or the
incorporation of a chemical treatment application into the upper subgrade layer. After the over -
excavation and replacement procedure has been completed, additional testing/observation
procedures such as "proof -rolling" the subgrade section will be required to verify the stabilization
has be accomplished. Another alternative as opposed to a moisture conditioning treatment of the
' underlying subgrade soils would be to incorporate a chemical treatment process, such as fly ash,
into the upper 12-inches of subgrade.
Proofrolling and recompacting the subgrade is recommended immediately prior to placement of
the aggregate road base section. Soft or weak areas delineated by the proofrolling operations
should be undercut or stabilized in -place to achieve the appropriate subgrade support.
Asphalt concrete underlain by crushed aggregate base course with or without a fly ash treated
subgrade and non -reinforced concrete pavement are feasible alternatives for the proposed on -site
' paved sections. Based on the subsurface conditions encountered at the site, and the laboratory
test results, it is recommended the on -site pavement improvement areas for the site be designed
using a minimum R-value of 5, based on soil classification results for the on -site subgrade
' materials.
' Pavement design methods are intended to provide structural sections with adequate thickness
over a particular subgrade such that wheel loads are reduced to a level the subgrade can
support. The support characteristics of the subgrade for pavement design do not account for
shrink/swell movements of an expansive clay subgrade such as the soils encountered on this
project. Thus, the pavement may be adequate from a structural standpoint, yet still experience
cracking and deformation due to shrink/swell related movement of the subgrade. It is,
therefore, important to minimize moisture changes in the subgrade to reduce shrink/swell
movements.
12
Geotechnical Engineering Report
Spring Creek Ranch - 88-Unit Multi -Family Development
South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
Eirracon
As presented on the enclosed boring logs and swell -consolidation test results, soft compressible
soils are present on this site. This report provides recommendations to help mitigate the effects of
soil shrinkage and settlement. However, even if these procedures are followed, some movement
and at least minor cracking in the structure's foundation and slabs should be anticipated. The
severity of cracking and other cosmetic damage such as uneven floor slabs will probably increase
if any modification of the site results in excessive wetting or drying of the compressible materials.
Eliminating the risk of movement and cosmetic distress may not be feasible, but it may be
possible to further reduce the risk of movement if significantly more expensive measures are used
during construction. Some of these options, such as the use of structural floors or mechanically
stabilizing the soft compressible materials are discussed in this report. We would be pleased to
discuss other construction alternatives with you upon request.
Additional floor slab design and construction recommendations for upper and lower level slabs
are as follows:
• Positive separations and/or isolation joints should be provided between slabs
and all foundations, columns or utility lines to allow independent movement.
• Control joints should be provided in slabs to control the location and extent of
cracking.
• Interior trench backfill placed beneath slabs should be compacted in accordance
with recommended specifications outlined below.
• In areas subjected to normal loading, a minimum 4-inch layer of clean -graded
gravel or aggregate base course should be placed beneath upper level interior
slabs.
' A minimum 8-inch layer of free -draining gravel should be placed beneath
basement floor slabs in conjunction with the underslab drainage system.
• Floor slabs should not be constructed on frozen subgrade.
• Other design and construction considerations, as outlined in the ACI Design
Manual, Section 302.1 R are recommended.
11
Geotechnical Engineering Report 1rerracon
Spring Creek Ranch - 88-Unit Multi -Family Development
South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
• Passive:
Cohesive soil backfill (on -site clay soils)...............................250 psf/ft
Cohesionless soil backfill (granular imported soils)...............350 psf/ft
• Adhesion at base of footing.....................................................500 psf
Where the design includes restrained elements, the following equivalent fluid pressures are
recommended:
' • At rest:
' Cohesive soil backfill (on -site clay soils).................................65 psf/ft
Cohesionless soil backfill (granular imported soils).................50 psf/ft
The lateral earth pressures herein do not include any factor of safety and are not applicable for
submerged soils/hydrostatic loading. Additional recommendations may be necessary if
submerged conditions are to be included in the design.
Fill against grade beams and retaining walls should be compacted to densities specified in
' Earthwork. Medium to high plasticity clay soils should not be used as backfill against retaining
walls. Compaction of each lift adjacent to walls should be accomplished with hand -operated
tampers or other lightweight compactors. Overcompaction may cause excessive lateral earth
' pressures, which could result in wall movement.
Seismic Considerations
The project site is located in Seismic Risk Zone I of the Seismic Zone Map of the United States
as indicated by the 1997 Uniform Building Code. Based upon the nature of the subsurface
' materials, Soil Profile Type "Sc" should be used for the design of structures for the proposed
project (1997 Uniform Building Code, Table No. 16-J). A site classification "C" should be used
' for the design of structures for the proposed project (2000 International Building Code, Table
No. 1615.1.1).
Floor Slab Design and Consideration
Conventional -type slab -on -grade construction procedures are feasible for the site, provided a
' separation of 4-feet exists between the bottom of the lower level floor slabs and the underlying
bedrock formation as well as to the maximum anticipated rise in groundwater.
1 10
Geotechnical Engineering Report
Spring Creek Ranch - 88-Unit Multi -Family Development
South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
1rerracan
To reduce the potential for groundwater fluctuation to impact foundation bearing soils and/or enter
the basement of the structure, installation of an interior dewatering system is recommended
where groundwater fluctuations are anticipated to be within 4-feet of the lower level floor slabs.
The interior dewatering system should, at a minimum, include an underslab gravel drainage layer
sloped to an interior perimeter drainage system. The interior drainage system should consist of a
properly sized perforated pipe, embedded in free -draining gravel, and placed in a trench at least
12 inches in width. The trench should be inset from the interior edge of the nearest foundation a
minimum of 12 inches. In addition, the trench should be located such that an imaginary line
extending downward at a 45-degree angle from the foundation does not intersect the nearest
edge of the trench. Gravel should extend a minimum of 3 inches beneath the bottom of the pipe.
The drainage system should be sloped at a minimum 1/8 inch per foot to a suitable outlet, such as
a sump and pump system.
The underslab drainage layer should consist of a minimum 8-inch thickness of free -draining gravel
meeting the specifications of ASTM C33, Size No. 57 or 67. Cross -connecting drainage pipes
should be provided beneath the slab at 15 to 20-foot intervals, and should discharge to the
perimeter drainage system.
To intercept the potential for surface water infiltration from impacting the foundation bearing
stratum and entering the lower level, an exterior perimeter drain is recommended for all buildings
where lower level construction is planned. The exterior drainage system should be constructed
around the exterior perimeter of the basement foundation, and sloped at a minimum 1/8 inch per
foot to a suitable outlet, such as a sump and pump system.
The exterior drainage system should consist of a properly sized perforated pipe, embedded in
free -draining gravel, and placed in a trench at least 12 inches in width. Gravel should extend a
minimum of 3 inches beneath the bottom of the pipe, and at least 1-foot above the bottom of the
foundation wall. The gravel should be covered with drainage fabric prior to placement of
foundation backfill.
Lateral Earth Pressures
For soils above any free water surface, recommended equivalent fluid pressures for
unrestrained foundation elements are:
• Active:
Cohesive soil backfill (on -site clay soils).................................50 psf/ft
Cohesionless soil backfill (granular imported soils).................35 psf/ft
N
Geotechnical Engineering Report lferracon
Spring Creek Ranch - 88-Unit Multi -Family Development
' South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
' barrels. Consideration should be given to obtaining a unit price for difficult caisson excavation in
the contract documents for the project.
' Shafts will probably remain open without stabilizing measures. However, pier concrete should be
placed soon after completion of drilling and cleaning and the same day as excavated.
' Groundwater was encountered during the subsurface exploration at an approximate depth of 5-
1/2 to 13-feet below site grades; therefore temporary casing will be required to
adequately/properly drill and clean piers prior to concrete placement. If encountered during
1 caisson drilling operations, the groundwater should be removed from each pier hole prior to
concrete placement. Pier concrete should be placed immediately after completion of drilling and
cleaning.
A maximum 3-inch depth of groundwater is acceptable in each pier prior to concrete placement. If
pier concrete cannot be placed in dry conditions, a tremie and/or a pump truck should be utilized
' for concrete placement. Due to potential sloughing and raveling, foundation concrete quantities
may exceed calculated geometric volumes. Pier concrete with slump in the range of 6 to 8 inches
' is recommended. If casing is used for pier construction, it should be withdrawn in a slow
continuous manner maintaining a sufficient head of concrete to prevent infiltration of water or the
creation of voids in pier concrete.
' Foundation excavations should be observed by the geotechnical engineer. A representative of
the geotechnical engineer should inspect the bearing surface and pier configuration. If the soil
conditions encountered differ significantly from those presented in this report, supplemental
recommendations will be required.
Lower Level Construction
Groundwater was encountered Boring Nos. 2 and 10 during the initial field exploration at
' approximate depths of 7-1/2 to 22-feet below site grades. When checked several days after
drilling, groundwater or a dry cave in (DCI) measurement were recorded in six (6) of the ten
' (10) test borings at approximate depths of 5-1/2 to 21-1/2-feet below existing site grades.
Therefore, full -depth basement construction is considered acceptable on the site provided the
lower level foundations bear a minimum of 3-feet above the maximum anticipated groundwater
' level, and/or an interior perimeter dewatering system is installed. This may prohibit the possibility
for basements along the northern portion of the site, adjacent to Spring Creek.
Perched groundwater may occur at times since the subsurface soils are relatively impermeable
and tend to trap water. Completion of site development, including installation of landscaping and
irrigation systems, may lead to perched groundwater development.
8
tGeotechnical Engineering Report lrerracan
Spring Creek Ranch - 88-Unit Multi -Family Development
' South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
' Final recommendations during "open -hole" or foundation excavation observations may vary
depending upon conditions at that time, additional overlot grading procedures or design
' elevations. Foundation excavations should be observed by the geotechnical engineer. If the soil
conditions encountered differ significantly from those presented in this report, supplemental
recommendations will be required.
' Foundation and walls should be reinforced as necessary to reduce the potential for distress
caused by differential foundation movement. The use of joints at openings or other discontinuities
' in walls is recommended.
Foundation Systems — Drilled Piers/Caissons
' Due to the close proximity of Spring Creek, the depth to bedrock, (i.e. 9 to 12-feet below site
grades in Boring Nos. 1 and 2) and depth to groundwater, consideration should be given to
supporting the units adjacent to Spring Creek on a grade beam and straight shaft drilled pier
foundation system. Also in areas where the 3-feet separation between the bottom of the
foundation system and the bedrock stratum cannot be achieved, then the proposed multi -family
residential building at that location should be supported by a grade beam and straight shaft drilled
pier/caisson foundation. Straight shaft piers, drilled a minimum of 8-feet into competent or harder
' bedrock, with minimum shaft lengths of 20-feet are recommended and should be designed using
a maximum end bearing of 15,000 psf, along with a skin friction of 1,500 psf. The drilled piers
should also be designed to maintain a minimum dead load of 5,000 psf.
' All piers should be reinforced full depth for the applied axial, lateral and uplift stresses imposed.
The tensile force created by the uplift force on each pier, with allowance for dead load, should
' determine the amount of reinforcing steel for expansion.
To reduce potential uplift forces on piers, use of long grade beam spans to increase individual pier
' loading, and small diameter piers are recommended. For this project, use of a minimum pier
diameter of 12-inches is recommended and a minimum 4-inch void space beneath grade beams
between piers. The void material should be of suitable strength to support the weight of fresh
' concrete used in grade beam construction, and to avoid collapse when foundation backfill is
placed.
' Drilling caissons should be possible with conventional single flight power augers within the
weathered portions of the underlying bedrock formation. Areas of well -cemented sandstone
' bedrock may be encountered throughout the site where specialized drilling equipment and/or rock
augers may be required. Excavations penetrating the well -cemented sandstone bedrock may
require the use of specialized heavy-duty equipment, together with rock augers and/or core
7
Geotechnical Engineering Report lrerracon
Spring Creek Ranch - 88-Unit Multi -Family Development
' South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
herein are followed and an interior perimeter drainage system is installed around any below grade
construction.
' Foundation Systems — Conventional Type Spread Footings
' Due to the anticipated loads, the type of construction proposed and the soil conditions
encountered within test borings analyzed to date, it is recommended the proposed multi -family
residential structures be supported by the use a conventional type spread footing foundation
system bearing upon the native subsoils at the upper levels and upon mechanically stabilized soils
' . or compacted structural fill material at the lower levels, where necessary. Footings bearing upon
the native subsoils should be designed using a maximum net allowable bearing pressure of 1,500
pounds per square foot (psf). In isolated areas, due to the potential for groundwater fluctuations
near the lower levels, (i.e. any foundations planned at depths of 6-feet or greater below existing
site grades) the subsurface soils may be in a slight soft/compressible state. Therefore, spread
footings in these locations, bearing upon mechanically stabilized soils designed for a net allowable
bearing pressure of 1,500 psf should be utilized. An approximate 12-inch layer of 1-1/2 inch
' washed aggregate embedded into the foundation bearing soils should be used to stabilize these
foundation zones.
An alternative would be to use spread footings bearing upon a minimum 3-foot depth of
compacted approved structural fill material designed for a net allowable bearing pressure of 2,000
psf. If this approach is used, the approved fill material should be moisture conditioned at or near
' optimum moisture content, placed in uniform lifts and mechanically compacted to at least 98
percent of Standard Proctor Density ASTM D698.
Exterior footings should be placed a minimum of 30 inches below finished grade for frost
protection and to provide confinement for the bearing soils. Finished grade is the lowest adjacent
grade for perimeter footings.
Footings should be proportioned to reduce differential foundation movement. Proportioning on
the basis of equal total movement is recommended; however, proportioning to relative constant
dead -load pressure will also reduce differential settlement between adjacent footings. Total
movement resulting from the assumed structural loads is estimated to be on the order of 1-inch.
Additional foundation movements could occur if water from any source infiltrates the foundation
soils; therefore, it is imperative proper drainage should be provided in the final design and during
construction for each structure. If the subsoils become wetted below the proposed structures,
movement exceeding 1-inch is likely.
M.
' Geotechnical Engineering Report lferracon
Spring Creek Ranch - 88-Unit Multi -Family Development
' South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
' drilling, groundwater or a dry cave in (DCI) measurement were recorded in six (6) of the ten
(10) test borings at approximate depths of 5-1/2 to 21-1/2-feet below existing site grades.
Temporary PVC pipe was installed in four of the borings to monitor future groundwater levels.
These observations represent groundwater conditions at the time of the field exploration, and
may not be indicative of other times, or at other locations. Groundwater levels can be expected
' to fluctuate with varying seasonal and weather conditions as well as volume of low within Spring
Creek located along the northern boundary of the site.
Based upon review of U.S. Geological Survey maps ('Hillier, et al, 1983), regional groundwater is
expected to be encountered in unconsolidated alluvial deposits on the site, at depths ranging from
10 to 20-feet below the existing ground surface at the project site.
ENGINEERING ANALYSES AND RECOMMENDATIONS
Geotechnical Considerations
' The site appears suitable for the proposed construction from a geotechnical engineering point of
view. Soft compressible soils were encountered at or near the lower level foundation bearing
strata, which will require particular attention in the design and construction. It is important to
establish and maintain good/positive surface drainage, especially in the immediate area of the
proposed residential footprints during and after construction.
' The following foundation system was evaluated for use on the site for the proposed addition:
• conventional -type spread footings bearing on the native subsoils at the upper levels
' and on mechanically stabilized soils or compacted structural fill material near the lower
levels. Foundation systems should be placed a minimum of 3-feet above the
underlying bedrock formation of the use of a grade beam and straight shaft drilled pier
foundation system should be used.
• Grade beam and straight shaft drilled piers in area where the foundation bearing level
' is into or within 3-feet of the underlying bedrock formation.
' Basement at select locations of the site and conventional slab -on -grade construction are
considered acceptable for use, provided the design and construction recommendations presented
' Hillier, Donald E.; Schneider, Paul A., Jr.; and Hutchinson, E. Carter, 1983, Depth to Water Table (1979) in the Boulder -
Fort Collins -Greeley Area, Front Range Urban Corridor, Colorado, United States Geological Survey, Map 1-855-I.
5
' Geotechnical Engineering Report lrerracon
Spring Creek Ranch - 88-Unit Multi -Family Development
South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
' the approximate locations of changes in soil types; in -situ, the transition of materials may be
gradual
' Field and Laboratory Test Results
' Field and laboratory test results indicate the native sandy lean clay and clayey sand soils are
medium stiff to soft with increase depths, exhibit low swell potential, a slight tendency to hydro -
compact when inundated with water and low to moderate bearing characteristics. At increase
depths the moisture contents are elevated and the cohesive soils become soft and compressible.
The bedrock, where encountered was predominantly weathered, exhibited low to moderate swell
potential and moderate to high bearing characteristics.
Swell — Consolidation Test Results
' The swell -consolidation test is commonly performed to evaluate the swell or collapse potential of
soils or bedrock for determining foundation, floor slab and pavement design criteria, as well as the
rate of consolidation. In this test, relatively undisturbed samples obtained directly from the ring
' barrel sampler or Shelby Tube sampling devices are placed in a laboratory apparatus and
inundated with water under a predetermined load. The swell -index is the resulting amount of swell
' or collapse as a percent of the sample's thickness after the inundation period. Samples obtained
at the 0.5 to 1-foot intervals for pavement analyses are typically pre -loaded and inundated with
water at approximately 150 pounds per square foot (psf) to simulate actual pavement loading
conditions. Samples obtained at the 3 to 4-foot intervals are generally pre -loaded and inundated
with water at approximately 500 pounds per square foot (psf), while samples obtained at the 7 to
9-foot intervals are pre -loaded and inundated with water at approximately 1,000 psf. After the
inundation period additional incremental loads are applied to evaluate the rate of consolidation.
For this assessment, we conducted 10 swell -consolidation tests at various intervals/depths
throughout the site. The swell index values for the soil samples tested at the 500 or 1,000-psf-
inundation pressure were negligible, with the exception of Boring No. 1 at an approximate depth of
' 19-feet within the bedrock formation, which resulted in an approximate (+) 3 percent. A few of the
samples revealed a tendency to hydro -compact when inundated with water and a few tested at or
near the lower foundation levels, (i.e. depths of 7 to 9-feet below site grades) where soft and
compressible conditions existed, an increased rate of consolidation was reported.
Groundwater Conditions
Groundwater was encountered Boring Nos. 2 and 10 during the initial field exploration at
approximate depths of 7-1/2 to 22-feet below site grades. When checked several days after
4
' Geotechnical Engineering Report lferracan
Spring Creek Ranch - 88-Unit Multi -Family Development
' South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
accordance with the general notes for Bedrock Classification. At that time, the field descriptions
were confirmed or modified as necessary and an applicable laboratory testing program was
1 formulated to determine engineering properties of the subsurface materials. Boring logs were
prepared and are presented in Appendix A.
' Laboratory tests were conducted on selected soil and bedrock samples and are presented in
Appendix B. The test results were used for the geotechnical engineering analyses, and the
development of foundation and earthwork recommendations. All laboratory tests were performed
' in general accordance with the applicable local or other accepted standards. Selected soil and
bedrock samples were tested for the following engineering properties:
' • Water Content • Atterberg Limits/Soil Classification
• Dry Density • Swell — Consolidation
SITE CONDITIONS
The site for the proposed multi -family development is a tract of land situated on the south side of
Spring Creek, north of Hull Street and east of Taft Hill Road. The site appears to have been
utilized as a pasture/grazing land, with several corrals outbuildings and two residences situated
along the southern boundary. The site is sparsely vegetated with native grasses and weeds, and
exhibits positive surface drainage in the north direction toward Spring Creek with an approximate
20 to 25-feet of relief.
SUBSURFACE CONDITIONS
Soil Conditions
Approximately 6-inches of silty topsoil consisting of organic matter and root growth was
encountered at the surface of each test boring. The native sandy lean clay or clayey sand soils
were encountered beneath the topsoil and extended to the depths explored or to the fine or
coarse granular strata below. Silty sand and silty sand with gravel layers were encountered at
approximate depths of 1-1/2 to 12-feet below existing site grades in several borings and either
extended to the depths explored or to the bedrock below. Siltstone/claystone bedrock was
encountered in Boring Nos. 1 and 2 at approximate depths of 9 to 12-feet below site grades and
extended to the depths explored, approximately 24-1/2 to 25-feet. The upper 4 to 9-feet of the
bedrock was weathered, however the underlying siltstone/claystone bedrock was hard/competent
with increased depths. The stratification boundaries shown on the enclosed boring logs represent
3
' Geotechnical Engineering Report lferracon
Spring Creek Ranch - 88-Unit Multi -Family Development
' South of Spring, East of Taft Hill Road
Fort Collins, Colorado
Project No. 20055046
' portion of the site. It is our understanding the multi -family building will wood framed, single to 2-
story residential units having slab on grade, crawl space, garden -level or full depth basement
' construction. Maximum wall and column loads will be on the order of about 1 to 3 kips per
lineal foot and 10 to 25 kips, respectively. We assume finished floor elevations will at or slightly
above existing site grades.
SITE EXPLORATION
The scope of the services performed for this project included a site reconnaissance by an
engineering geologist, a subsurface exploration program, laboratory testing and engineering
analyses.
Field Exploration
A total of ten (10) test borings were drilled for the project on March 11, 2005, at the locations
shown on the Test Boring Location Diagram, Figure 1 included in Appendix A. The test borings
were drilled to an approximate depth of 15 to 25-feet below existing site grades and were
advanced with a truck -mounted drilling rig, utilizing 4-inch diameter solid stem augers.
The borings were located in the field by pacing from existing site features and by using a hand
held GPS unit. Ground surface elevations at each boring location were estimated by linear
interpolations based on the topographic contours presented on the Fort Collins quadrangle map.
The accuracy of boring locations and elevations should only be assumed to the level implied by
the methods used.
Lithologic logs of each boring were recorded by the engineering geologist during the drilling
operations. At selected intervals, samples of the subsurface materials were taken by means of
driving split -spoon and ring barrel samplers.
Penetration resistance measurements were obtained by driving the split -spoon and ring barrel into
the subsurface materials with a 140-pound hammer falling 30 inches. The penetration resistance
value is a useful index in estimating the consistency, relative density or hardness of the materials
encountered.
Laboratory Testing
All samples retrieved during the field exploration were returned to the laboratory for observation by
the project geotechnical engineer and were classified in general accordance with the Unified Soil
Classification System described in Appendix C. Samples of bedrock were classified in
2
GEOTECHNICAL ENGINEERING REPORT
' SPRING CREEK RANCH
PROPOSED MULTI -FAMILY RESIDENTIAL DEVELOPMENT
SOUTH OF DRAKE ROAD AND SPRING CREEK,
' EAST OF TAFT HILL ROAD, and NORTH OF HULL STREET
FORT COLLINS, LARIMER COUNTY, COLORADO
' TERRACON PROJECT NO. 20055046
INTRODUCTION
' This report contains the results of our geotechnical engineering exploration for the proposed 88-
unit multi -family residential development project having full -depth basement construction to be
located south of Drake Road, north of Hull Street and east of Taft Hill Road, south of Spring
' Creek in southwest Fort Collins, Colorado. The site is located in the Northwest % of Section 27,
Township 7 North, Range 68 West of the 6th Principal Meridian, Larimer County, Colorado.
' The purpose of these services is to provide information and geotechnical engineering
recommendations relative to:
' • subsurface soil and bedrock conditions
• groundwater conditions
• foundation design and construction
• floor slab design and construction
• basement construction
• lateral earth pressures
' • pavement design and construction
' • earthwork
• drainage
' The recommendations contained in this report are based upon the results of field and laboratory
testing, engineering analyses, and experience with similar soil conditions, structures and our
understanding of the proposed project.
' PROPOSED CONSTRUCTION
The project as we understand it is to develop an approximate 10-acre vacant tract of land
located south of Drake Road, east of Taft Hill Road, and north of Hull Street, south of Spring
Creek into an approximate 818-unit multi -family residential development. The project will include
ten (10) 2-plex buildings, one (1) 4-plex building, two (2) 6-plex buildings, three (3) 7-plex
buildings, and three (3) 8-plex buildings along with associated parking and drive areas, along with
infrastructure consisting of utilities, roadways, and a detention pond situated near the northeast
TABLE OF CONTENTS
Page No.
Letter of Transmittal.............................................................................................I
INTRODUCTION............................................................................................................................. 1
PROPOSED CONSTRUCTION..................................................................................................... 1
SITEEXPLORATION..................................................................................................................... 2
FieldExploration................................................................................................................... 2
LaboratoryTesting................................................................................................................ 2
SITECONDITIONS......................................................................................................................... 3
SUBSURFACE CONDITIONS....................................................................................................... 3
SoilConditions...................................................................................................................... 3
Field and Laboratory Test Results........................................................................................ 4
Swell - Consolidation Test Results....................................................................................... 4
Groundwater Conditions....................................................................................................... 4
ENGINEERING ANALYSES AND RECOMMENDATIONS.......................................................... 5
Geotechnical Considerations................................................................................................
5
Foundation Systems — Conventional Type Spread Footings ...............................................
6
Foundation Systems — Drilled Piers/Caissons.............................................................
7
Lower Level/asement Construction......................................................................................
8
LateralEarth Pressures........................................................................................................
9
SeismicConsiderations......................................................................................................
10
Floor Slab Design and Construction...................................................................................
10
Pavement Design and Construction...................................................................................
11
Earthwork............................................................................................................................
15
GeneralConsiderations............................................................................................
15
SitePreparation........................................................................................................
15
SubgradePreparation....................................................................:..........................
16
Fill Materials and Placement.....................................................................................
16
Excavation and Trench Construction........................................................................
17
Additional Design and Construction Considerations..........................................................
18
Exterior Slab Design and Construction.....................................................................
18
UndergroundUtility Systems....................................................................................
18
SurfaceDrainage......................................................................................................
19
GENERALCOMMENTS.............................................................................................................. 19
APPENDIX A
Boring Location Diagram
Logs of Borings
APPENDIX B
Laboratory Test Results
APPENDIX C
General Notes
Geotechnical Engineering Report lferracon
Spring Creek Ranch - 88-Unit Multi -Family Development
South of Spring, East of Taft Hill Road
Fort Collins, Colorado
' Project No. 20055046
incorporating clean graded washed gravel embedded into the bearing stratum, or by installing an area
underdrain system. Based on the subsurface conditions encountered, the proposed multi -family
residential structures could be supported by conventional spread footings bearing on the native subsoils,
enhanced/modified native soils, or approved engineered fill material, provided the foundation systems
' are placed a minimum of 3-feet above the underlying bedrock formation. Due to the close proximity of
Spring Creek, the depth to bedrock, (i.e. 9 to 12-feet below site grades in Boring Nos. 1 and 2) and
' depth to groundwater, consideration should be given to supporting the units adjacent to Spring Creek on
a grade beam and straight shaft drilled pier foundation system.
Conventional floor slab construction is feasible for the site provided the recommendations contained
herein are followed, and placed a minimum of 4-feet above the underlying, moderately expansive
bedrock formation. We understand interior roadways/entrance drives at this time are considered non -
jurisdictional City of Fort Collins roadways. However, if these are to be considered as part of the
network of City of Fort Collins' local residential roadway system, a separate geotechnical engineering
evaluation will be required and should be conducted in general accordance with the Larimer County
Urban Area Street Standards (LCUASS) Pavement Design Criteria after the utilities have been
installed and the subgrade has been prepared to "rough -final" subgrade elevations. Other design and
construction recommendations based upon geotechnical conditions are presented in the report.
We appreciate being of service to you in the geotechnical engineering phase of this project, and are
prepared to assist you during the construction phases as well. If you have any questions concerning
this report or any of our testing, inspection, design and consulting services please feel free to contact
us.
Sincerely,dw
VIIJ Er-4i
TERRACO� 9!
David A. Ric ? E
Geotechnical J. ent Manager
Reviewed by: ouglas J. Jobe, P.E.
Regional Manager
Copies to: Addressee (2)
VF Ripley Associates, Incorporated — Sandy McFeron (4)
City of Fort Collins — Engineering Department (2): Mr. Rick Richter
April 8, 2005 Irerracon
Consulting Engineers & Scientists
Terracon Consultants, Inc.
Mr. Michael Mintz 301 North Howes
Spring Creek Ranch LLC Fort Collins, Colorado 80521
Phone 970.484.0359
PO Box 7701 Fax 970.484.0454
Avon, Colorado 81620 www.terracon.com
' Re: Geotechnical Engineering Report
Spring Creek Ranch — Proposed Multi -Family Residential Development
South of Drake Road and Spring Creek, and East of Taft Hill Road
' Fort Collins, Larimer County, Colorado
Terracon Proposal No. 20055046
' Terracon has completed a geotechnical engineering exploration for the proposed 81-unit multi -family
residential development project having full -depth basement construction to be located south of Drake
' Road, north of Hull Street and east of Taft Hill Road, south of Spring Creek in southwest Fort Collins,
Colorado. The project will include ten (10) 2-plex buildings, one (1) 4-plex building, two (2) 6-plex
buildings, three (3) 7-plex buildings, and three (3) 8-plex buildings along with associated parking and
' drive areas. This study was performed in general accordance with our Proposal No. D2004327 dated
September 10, 2004.
The results of our engineering study, including the boring location diagram, laboratory test results, test
boring records, and geotechnical recommendations needed to aid in the design and construction of
foundations, on -site pavement areas, and other earth connected phases of this project are attached.
Approximately 6-inches of silty topsoil consisting of organic matter and root growth was encountered at
the surface of each test boring. The native sandy lean clay or clayey sand soils were encountered
beneath the topsoil and extended to the depths explored or to the fine or coarse granular strata below.
Silty sand and silty sand with gravel layers were encountered at approximate depths of 1-1/2 to 12-feet
below existing site grades in several borings and either extended to the depths explored or to the
bedrock below. Siltstone/claystone bedrock was encountered in Boring Nos. 1 and 2 at approximate
depths of 9 to 12-feet below site grades and extended to the depths explored, approximately 24-1/2 to
25-feet. Groundwater was encountered Boring Nos. 2 and 10 during the initial field exploration at
approximate depths of 7-1/2 to 22-feet below site grades. When checked several days after drilling,
groundwater or a dry cave in (DCI) measurement were recorded in six (6) of the ten (10) test borings
at approximate depths of 5-1/2 to 21-1/2-feet below existing site grades.
The results of our field exploration and laboratory testing completed for this study indicate the upper
cohesive native sandy lean clay or clayey sand strata exhibited low swell potential, a slight tendency
to hydro -compact when inundated with water and low to moderate bearing capabilities. However, at
anticipated lower foundation levels at several locations, the soils exhibited higher moisture contents
and soft compressible conditions due to the presence of groundwater at approximate depths of 7 to
13-feet below site grades. Due to the depth of groundwater, consideration should be given to limiting
the depth of excavations in these areas, enhancing the lower level bearing capacity characteristics by
Delivering Success for Clients and Employees Since 1965
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GEOTECHNICAL ENGINEERING REPORT
SPRING CREEK RANCH
PROPOSED MULTI -FAMILY RESIDENTIAL DEVELOPMENT
SOUTH OF DRAKE ROAD AND SPRING CREEK,
EAST OF TAFT HILL ROAD, and NORTH OF HULL STREET
FORT COLLINS, LARIMER COUNTY, COLORADO
TERRACON PROJECT NO. 20055046
APRIL 8, 2005
Prepared for.
SPRING CREEK RANCH, LLC
P.O. BOX 7701
AVON, COLORADO 81620
ATTN: MR. MICHAEL MINTZ
Prepared by.
Terracon
301 North Howes Street
Fort Collins, Colorado 80521
Irerraca