HomeMy WebLinkAboutLINDENMEIER ESTATES PUD - PRELIMINARY - 24-94 - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTNo Text
r
l
1 �
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Boring
No.
Depth
1
3.0
3
3.0
5
3.0
8
3.0
9
3.0
14
3.0
15
3.0
17
3.0
21
3.0
SU14 ARY OF TEST RESULTS
% Moisture
Before Test
18.5
5.6
5.3
9.6
17.3
15.7
18.3
19.9
15.4
Dry Density
P.C.F.
105.3
98.9
107.5
97.5
100.8
123.5
109.7
114.6
108.2
Swelling
Pressure PSF
1,975
215
315
660
505
1,420
390
1,450
1,200
SUMMARY OF TEST RESULTS
BORING
NO.
DEPTH
FT.
%
MOISTURE
DRY DENSITY
P.C.F.
UNCONFINED COMPRESSIVE:
STRENGTH-P.S.F.
WATER SOLUBLE
SULFATES-%
PENETRATION
BLOWS/INCHES
17
3.0-4.0
19.9
24/12
7.0-8.0
17.4
46/12
14.0-15.0
18.8
48/12
18
3.0-4.0
14.6
8/12
7.0-8.0
30.4
50/11
14.0-14.3
13.9
42/3
19
3.0-4.0
21.4
103.8
800
4.0-5.0
5/12
7.0-8.0
27.1
9/12
14.0-15.0
18.7
47/12
20
3.0-4.0
26.4
4/12
7.0-8.0
21.3
7/12
14.0-15.0
22.1
50/12
21
3.0-4.0
15.4
49/12
7.0-7.5
15.4
39/6
14.0-14.9
16.7
50/1W
EMPIRE LABORATORIES, INC.-_L.._-____...__ _
SUMMARY OF TEST RESULTS
BORING
NO.
DEPTH
FT.
%
MOISTURE
DRY DENSITY
P.C.F.
UNCONFINED COMPRESSIVE
STRENGTH-P.S.F.
WATER SOLUBLE
SULFATES-%
PENETRATION
_ BLOWS/INCHES
9
3.0-4.0
17.3
12/12
7.0-8.0
5.6
12/12
14.0-14.2
17.5
50/2
10
3.0-4.0
2/1-2
7.0-8.0
28.5
4/12
14.0-14.3
14.3
50/4
11
3.0-4.0
25.0
4.0-5.0
2/12
7.0-8.0
23.7
10/12
14.0-14.5
15.8
50/5
12
3.0-4.0
9.8
9/12
7.0-8.0
14.2
12/12
14.0-14.3
22/3
13
3.0-4.0
11.2
13/12
7.0-8.0
13.9
10/12
14.0-14.5
31/12.
14
3.0-4.0
15.7
113.5
11,530
4.0-5.0
17/12
7.0-8.0
13.3
8/12
1.4.0-14.5
50/52
15
3.0-4.0
18.3
109.7
31200
4.0-5.0
29/12
7.0-8.0
16.7
50/12
14.0-14.5
15.8
42/6
16
3.0-4.0
27.3
7/12
7.0-8.0
22.2
10/12
14.0-15.0
21.0
19/12
EMPIRE LABORATORIES, INC. -
. y
- f
n
SUMMARY OF TEST RESULTS
Y.
BORING
NO.
DEPTH
FT.
%
MOISTURE
DRY DENSITY
P.C.F.
UNCONFINED COMPRESSIVE
STRENGTH-P.S.F.
WATER SOLUBLE
SULFATES-%
PENETRATION
BLOWS/II4CHES
1
3.0-4.0
18.5
108.4
14,290
4.0-5.0
15/12
7.0-8.0
26.8
20/12
14.0-14.5
16.6
50/5
2
3.0-4.0
14.7
8/12
7.0-8.0
50/12
14.0-15.0
45/12
3
3.0-4.0
5.6
12/12
7.0-7.9
50/9
14.0-15.0
38/12
4
3.0-4.0
6.4
17/12
7.0-8.0
14/12
14.0-15.0
26/12
5
3.0-4.0
5.3
113.5
71065
4.0-5.0,
23/12
7.0-8.0
15/12
14.0-15.0
29/12
6
3.0-4.0
5.5
13/12
7.0-8.0
18.4
10/12
14.0-15.0
25/12
7
3.0-4.0
11.7
10/12
7.0-8.0
13/12
14.0-15.0
44/12
8
3.0-4.0
9.6
14/12
7.0-8.0
37/12
14.0-14.8
5.0/9.
_-- _-,
- -- EMPIRE
L&MRATORILS, INC. _---
----------- ---------
---------------
' LOG OF BORINGS
1
ELEVAT/ON A0.
4980
1
t 4975
' 4970
4965
o
■
�wr
m
m
m
WA
m
m
o
m
m
m
-14-
LOG OF BORINGS
FLEVAT/ON a I6 o• 17 No.
4985
4980
4975
4970
4965 `-
4)G5
4955
-13 --
.r
497`_
497(
496!
496
495
LOG OF BORINGS
471
i
2
90/12
..
71
13/12
i
/
17 12
�.
4 2 6
10 12
'
8 12
o,
p O
v
p•e-
• o �O
v
o.�
ey•.
m
50 5
i
-12-
LOG OF BORINGS
ELEVAT/ON No.10 NO. if No.l
4970
4965
496C
495`
/
i.
2/12
,.
,
10 12
/
9/12
/
22 34/12
4950
-11-
I ,
II
I 1
LOG OF BORINGS
ELEVAVON No. No.8 a.9
4965
4960
4955
4950
WA
.'A
w
WA
OVA
OVA
MAP
50/2
-10-
CAAMOC i AOl DDT/ DICC fklr
LOG OF BORINGS
El- EVAT(ON
496E
r...D
495E
495(
®e
Nip
SWARM
w
®d_��
LOG OF BORINGS
EL EVA T/ON NO• % 0• Z No. 3
4965
496C
495_
4950
AM
® FILL
SILT
CLAYEY SILT
i
SANDY SILT
z CLAY
zSILTY CLAY
ZJ SANDY CLAY
SAND
LiSILTY SAND
CLAYEY SAND
a
KEY TO BORING LOGS
p 6
n aA
GRAVEL
A.
n
•a
-SAND & GRAVEL
SILTY SAND & GRAVEL
a
COBBLES
o �•
SAND, GRAVEL & COBBLES
®
WEATHERED BEDROCK
SILTSTONE BEDROCK
®
CLAYSTONE BEDROCK
SANDSTONE BEDROCK
®
LIMESTONE
a
SHELBY TUBE SAMPLE
STANDARD PENETRATION DRIVE SAMPLER
WATER TABLE 24 HOURS AFTER DRILLING
5/12 indicates that 5 blows of a 140 pound hemmer falling 30 Inches was required to penetrate 12 Inch".
—7—
TEST BORING LOCATION PLAN
SCALE /t= SOO wELO CANAL
%
A I�^E% No. 20 Na 21 I
� 1, � J�-
No. IB Na. /7 No. /G
'No.10 Na. 11 No. 12 No. 13
No. /
Na /4 ;
.,. ' •.MARSH AREA
No. 8 No. 7 No. G
A%.-1-- No. 2 No. 3 No. 4 No. 5
1%EN07-,C9 %E5T BORING
• UENO7E5 CA6.rR TEST 90RIIV6;
AREA I
A REA 11
a
I i
I!
1
1
7
[1
I
1
LI
all slabs on grade in this area be placed directly on the undis-
turbed soil which has been slightly wetter: down prior to place-
ment of any concrete. All slah.s on grade should be structurally
independent of bearing memiers and should be reinforced with
reinforcing running through the construction joints. All slabs
cn grade in Area II should be underlain_ by a minimum of four
(4) inches of gravel or crushed rock devoi3 of fines. Fill
material supporting slats on grade should be a non -expansive,
granular -type material compacted at optimum moisture to at least
ninety percent ("40€) of Standard Proctor Censity (-"S'TM CG96-70).
Pond r.rea and Lrainage
It is our understanding that a ponce is to be constructed in
t:.e Soutnwest corner of t e site in tile area of the existing
rarsh. Due to the relatively ir--pervious nature of the clay soil,
the absence of cravel under the clav and the abundance of ground-
r:ater in the area, it is felt that the proposed pond constructici
is feasible. It should be noted that impounding hater in this
area may change the gravel aquifer characteristics Fast of the
pond location. In doing this, eater levels may tend to rise in
the Eastern Porticr of tl- site.
"o lce.•er the water table in. the Northern and .tiort iwestern
portion of the site and: to control seepage along the Scut'_i .base
of the Larimer anc Weld Canal, it is suggested that a suh-drain
he installed at the site. The drain should be rlaced Lelow the
existing canal from an area fast of Boring No. Z,0 Vest to the
West property line. The suhdrain_ should then be placed along
tine Nest property ling Southward ane empty into tie proposed
pond.
GENEVAL Coy*FENTs
It should be noted that this was a preliminary investiga-
tion and the Learirg caracities recemmend.cd in this report are
rased on preliminary tests.. Due to variations in soil and
groundwater conditions and swelling pressures encountered at the
site, it is strongly recormended that additional test borings be
made prior to construction. Samples obtained from these test
Lorings should be suhiected to testing and inspection in the
laboratory to prcvide a sound basis for deterrr.inina the physical
properties anal bearing capacities of the soils encountered.
1
-5-
7
L
1
1
[1
1
load plus maximum live load). To counteract swelling pressures,
which will develop if the dry subsoils inArea I become wetted,
all footings, pads and grade beams should be designed for mini-
mum dead loads of five hundred pounds (500`) to twent-y-five hun-
dred pounds (2,5006) per square foot.
Area II
In view of the soil conditions encountered in this part of
the site, it is recommended that the substructures be supported
by conventional -type, continuous spread footings. All footings
should be founded on the original undisturbed soil a minimum of
thirty (30) inches below finished grade for frost protection.
Footings at the above level may be designed for maximum allow-
able bearing capacities of one thousand pounds (1,0001) to fif-
teen hundred pounds (1,5001) per square foot (dead load plus
maximura live load) .
A feasible foundation alternate would be a drilled pier
foundation system. It is recommended that all piers be straight
shaft and that they be drilled a minimum of two (2) feet into
the firm bedrock stratiLm. Piers at this level may be designed
for maximum end bearing pressure of fifteen thousand pounds
(15,000#) to forty thousand pounds (40,000?) per square foot.
To counteract swelling pressures, all piers should be desianed
for minimum dead loads of two thousand pounds (2,000*) to_-sevent�
five hundred pounds (7,500f) per square foot. In. areas wb ere the
firm bedroc% stratum is encountered, close to the surface, the
substructures may be supported by a pad and grade beam foundation
system. Pads founded on the bedrock stratum nay be designed for
maximum allowable bearing capacities of ten thousand pounds
(10,000t) to fifteen thousand pounds (15,000-�) per square foot
(dead load plus maximum live load). To counteract swelling pres-
sures, all pads and grade beams should be designed for minimum
dead loads of two thousand pounds (2,000#) to five thousand
pounds (5,000$) per square foot. It is important that a four (4)
inch minimum void be provided under all grade beams.
Basements
Basement construction is feasible over most of Area I pro-
viding the finished basement floor slabs are placed a minimum of
two (2) feet above maximum seasonal groundwater elevations. Due
to the extremely high groundwater elevations encountered in Bor-
ings No. 1 and lb in Pxea I and in all of Area II, it is felt
that basement construction is not feasi'hle in these areas.
Groundwater elevations are such in Borings No. 2, 9, 17 and 18,
that basement construction may or may not be feasible depending
upon seasonal fluctuations. Therefore, it is recommended that
garden -level construction be considered in lieu of basements in
these areas.
Slabs on Grade
Due to the expansive nature of the subsoils in Pxea I, it
is felt that floating slabs are feasible. It is recommended that
and gravels at depths of three to twelve and
one-half feet below the surface in Borings
No. 1, 9 through 11, and 15 through 21 and ex-
'
tends to greater depths. The upper one-half
to four feet of the bedrock is highly weath-
ered; however, t'.e underlying bedrock is firm
and dense and exhibits very high bearing char-
'
acteristics. Like the upper clays, the drier
siltstone and clayatone bedrock exhibits low
to moderate swelling potentials wren wetted.
'
(C) Groundwater: At the time of the investigation,
free groundwater was encountered at depths of
'
zero to fourteen feet below tl:e surface. No
free groundwater was encountered to depths of �
fifteen feet below tl:e surface in Borings No.
15 and 21. water levels in this area are sub-
'
ject to change depending upon seasonal varia-
tions and irrigational flows on and adjacent
to the site. Five test borings at the site i
'
were cased to ol�serve these seasonal fiucua- j
tions .
tPECM1,M
NDATI0NS Alib DISCi'SSI! iJ
'
Foundation
It is our understanding that the proposes' structures are to
consist of apartments, townhouses and single-family residences.
1
bue to differences in the physical properties of the soils
encountered at the site, the area will be divided into two, Parts
in this report for the purpose of determining foundation types
and bearing values of the soils encountered. Area II is that
portion of the site which has high groundwater and generally
'
non-ex�,:ansive soils. these areas are located in the Marsh area
at the Southwest corner of the site, and below the Larimer and
Weld Canal in the North Central portion of the site. Area I
constitutes the remainder of the site (See Test Boring Location,
Plan).
Area I
'
In view of the tyke of structures proposed and the soil con-
ditions encountered in e,.rea I, it is recommended that the sub-
structures in this area be supported by conventional -type, con-
tinuous spread footings, continuous grade beams.and/or a pad and
grade bean foundation system. All footings, grade beards and pads
should be founded on the original undisturbed soil a minimum of
thirty (30) inches below finished grade for frost protection.
Bearing values bases: upon the preliminary investigation for the
upper soils in .'sea I vary from:. twenty-five hundred pounds
'
(2,500$) to six thousand pounds (6,0001) per square foot (dead
'
-3--
SOIL AND GROUNDWATER CONDITIO14S
The soil profile at the site consists of strata of mater-
ials arranged in different combinations. In order of increasing
depths, they are as follows:
(1) Silty Topsoil: The entire site is overlain by
a one-half to one -foot layer of silty topsoil.
The upper six inches of the topsoil have been
penetrated by plant roots and organic natter
and should not be used as a bearing soil or
backfill material. Four feet of wet, organic,
clay fill is located in Boring No. 20. This
material is not suitable as a bearing soil or
as backfill material.
(2) Silty Clay: This stratum underlies the top-
1 fill in Borings No. 1, 9, 10, 11,
14, 15, 17, 19, 20 and 21 at depths of three
to thirteen feet below the %urface. The
brown, silty clays are lUghly plastic and have
varying moisture contents. in their near sat-
urated state, the silty clays exhibit low
:,earing characteristics and consolidate readily
upon. loadinq. The drier silty clays exhibit
generally moderate bearing caracteristics,
and upon wetting, these clays exhibit moderate
swelling potentials.
(3) Sandy, Silty Clay: A layer of brown., sandy,
silty clay underlies the topsoil in the -area
of Borings No. 2_ through 8, 12, 13, 15, and
18 and extends to depths of five to twelve
and one-half feet below the surface. The
sandy clays are slightly plastic, contain
varying amounts of fine sand and exhibit
generally moderate bearing.characteristics in
their dry to moist natural state. When wetted,
the drier sandy silty clays exhibit slight to
moderate swelling potentials.
(4) Sand;. Gravel and Cobbles_ The gravel stratum
underlies the upper clays in the Southern part
of the site in Borings No. 1 through 9 and 12
through 14 and extends to depths of nine to
greater than fifteen feet below the surface.
The gravels are poorly graded, clean and exhi-
bit moderate to high bearing characteristics in
their medium dense to dense natural state. It
is estimated that the cobbles, scattered through-
out the gravel stratum, vary in size up to
twelve inches in diameter.
(5) Claystone, Siltstone and Sandstone (Bedrock):
The bedrock stratum un erliesthe upper clays
-2-
11
11
L!
1
i
11
1
SCOPE
REPORT
OF A
PRELIMINARY
SOILS ALAI*, FOUNDATION INVESTIGATION
This report presents the results of a Preliminary Soils and
Foundation Investigation prepared for the proposed unit develcp-
ment located on Lindenmeier Road, Northeast of Fort Collins,
Colorado. The investigation was carried out by means of test
borings and laboratory testing of samples obtained from these
borings.
The primary objective of this investigation was to dote
the suitability of the site for construction purposes.
SITE INVESTIGATION
The field investigations, carried out en June 21, 22 and
23, 1972, consisted of drilling, logging, and sampling twenty-
one test borings. The locations of the test borings are shown
on the Test Boring Location Plan included on page 6 of this re-
port. Boring logs prepared from the field logs are shown on
pages 6 through 14. These logs show soils encountered, locati
of sampling, and groundwater at the time of the investigation.
All borings were advanced with a four -inch diameter,
continuous -type, power -flight auger drill. During the drilling
operations, a field engineer from -Empire Laboratories, Inc., was
present and made a continuous visual inspection of the soils
encountered.
SITE LOCATION AND DESCRIPTION
The proposed site is located on Lindenmeier Road, Northeast
of Pori: Collins, Colorado. tore particularly, the site is des-
cribed as a tract of land situate in the Southeast 1/4 of Section
36, Township B North, Range 69 West, and the Borth 1/2 of the
Northeast 1/4 of Section 1, Township 7 North, Range 69 West of
the 6th P.M., Larimer County, Colorado.
The majority of the site is relatively flat and has minor
drainage to the Southwest. The North edge of the site slopes to
the Southeast and Southwest from the Larimer and Weld Canal,
which forms the Northern portion of the site. The majority of
the site is under vegetation and several residences and a,it
buildings are located in the Northeastern corner of the site. A
large marsh is located in the Southwest corner of the area.
-�
11
'
�PSOR4TO
�
W
�
T
N
1
Empire Laboratories, Inc.
Materials and Foundation Engineers
duZy SB, 1972
Don Pavel Land Company
Suite 420
Savings Building
Fort COllins, Colorado 20521
Dear ^.'r. Pavel:
We are pleased to submit our Peport of a PrraZininary Soils and
Pcundation Investigation prepared for the proposed planned ree-
idental development located Northeast of Fort Collins, Colorado,
as requested.
Based upon our findings in the subsurface, we feel that the
site is suitable for the proposed construction. The accompany -
inn report presents our findings in the subsurface and our
recor,mendatione based upon the preliminary findings.
Very truly yours,
E'Pl nib' LABDRd CP._TES, INC.
/Je Cf�O do
Neil R. Shkarrod
Engineering Ceolcgist
rro
_Reviewed by:
I f
Chester C. Smith, P.E.
Vice President
Pt0157EREQ
aD d 1
V
* H 4808
O. 5
\�T�'YGINEER t'��Cw�O�
OFFICE AND LABORATORY-214 NORTH HOWES 0 P.O. SOX 149 _ FORT COT T INS, COLORADO M21 0 TELEPHONE ARZA 303/4844359
TABLE OF CONTENTS
Table of Contents ..................................
Letter of Transmittal ..............................
Report .............................................
Test Boring Location Plan ..........................
Key to Borings .....................................
Log of Borings .....................................
Summary of Test Results ............................
-i-
REPORT
OF A
PRELIMINARY
' SOILS AND FOUNDATIO24
INVESTIGATION
Fcn
DON PAV= LAND COMPANY
' FORT COLLINS, COLORADO
1
1
1
1
PROJECT NO. 1192-72
BY
EMPIRE LABORATORILS, INC.
214 NORTH IIOWES STREET
FORT COLLINS, COLORADO
fi�521
M O I S T U R E- DENS ITY DETERMINATION
Samples of representative fill materials to be placed shall be fur-
nished by the contractor to• the soils engineer for determination of
maximum density and optimum moisture or percent of Relative Density
for these materials. Tests for this determination will be made using
methods conforming to requirements of ASTM D 698, ASTM D 1557, or
ASTM D 2049. Copies of the results of these tests will be furnished
to the contractor. These test results shall be the basis of control
for all compaction effort.
D E N S I T Y T E S T S
The density and moisture content of each layer of compacted fill will
be determined by the soils engineer in accordance with ASTM D 1556,
ASTM D 2167, or ASTM D 2922. Any material found not to comply with
the minimum specified density shall be recompacted until the required
density is obtained. The results of all density tests will be furnished
to both the owner and the contractor by the soils engineer.
P L A C I N G F I L L
No sod, brush, frozen material, or other unsuitable material shall be
placed in the fill. Distribution of material in the fill shall be such
as to preclude the formation of lenses of material differing from the
surrounding material. The materials shall be delivered to and spread
on the fill surface in a manner which will result in a uniformly com-
pacted fill. Prior to compacting, each layer shall have a maximum
thickness of eight inches, and its upper surface shall be approximately
horizontal.
M O I S T U R E C 0 N T R 0 L
While being compacted, the fill material in each layer shall as nearly
as practical contain the amount of moisture required for optimum com-
paction or as specified, and the moisture shall be uniform throughout
the fill. The contractor may be required to add necessary moisture to
the fill material and to uniformly mix the water with the fill material
if, in the opinion of the soils engineer, it is not possible to obtain
uniform moisture content by adding water on the fill surface. If, in
the opinion of the soils engineer, the material proposed for use in
the compacted fill is too wet to permit adequate compaction, it shall
be dried in an acceptable manner prior to placement and compaction.
C O M P A C T I O N
When an acceptable, uniform moisture content is obtained, each layer
shall be compacted by a method acceptable to the soils engineer and
as specified in the foregoing report as determined by applicable
standards. Compaction shall be performed by rolling with approved
tamping rollers, pneumatic -tired rollers, three -wheel power rollers,
vibratory compactors or other approved equipment well -suited to the
soil being compacted. If a sheepfoot roller is used, it shall be
orovided with cleaner bars attached in a manner which will prevent
the accumulation of material between the tamper feet. The rollers
should be designed so that the effective weight can be increased.
I 1
1
[1
1
1
I
APPENDIX A
Suggested Specifications for Placement of Compacted Earth Fill
and/or Backfills.
G E N E R A L
A soils engineer shall be the owner's representative to inspect and
control all compacted fill and/or compacted backfill placed on the
project. The soils engineer shall approve all earth materials prior
to their use, the methods of placing, and the dearee of compaction
obtained. A verification of approval from the soils engineer will be
required prior to the owner's final acceptance of the filling opera-
tions.
M A T E R I A L S
Soils used for all compacted fill beneath interior floor slabs shall
be a oranular, nonexpansive type. The upper 12" to 18" of compacted
earth backfill placed adjacent to exterior foundation walls shall be
an impervious, nonexpansive material. No material having a maximum
dimension greater than six inches shall be placed in any fill. All
materials proposed for use in compacted fill and/or compacted back -
fill shall be approved prior to their use by the soils engineer.
PREPARATION OF S U B G R A D E
All topsoil, vegetation, debris, and other unsuitable material shall
be removed to a depth satisfactory to the soils engineer before begin-
nino Preparation of the subgrade. The subarade surface of the area
to be filled shall be scarified a minimum depth of six inches, mois-
tened as necessary, and compacted in a manner specified below for the
subsequent layers of fill. Fill shall not be placed on frozen or
muddy ground.
1
SUMMARY OF TEST RESULTS
BORING DEPTH % DRY DENSITY UNCONFINED COMPRESSIVE WATER SOLUBLE PENETRATION
NO. FT. MOISTURE P.C.F. STRENGTH-P.S.F. SULFATES-% BLOWS/INCHES
6
3.0-4.0
21.2
7.5-8.2
2.6
13.5-14.1
17.7
7
3.0-4.0
16.1
7.0-8.0-
12.2
13.5-14.0
2.4
8
3.0-4.0
19.8
7.0-8.0
17.0
13.5-14.3
16.2
9
3.0-4.0
27.0
7.0-8.0
21.0
13.5-14.5
17.6
10
$.0-4.0
17.3
7.0-8.0
24.5
13.5-14.5
17.5
11
3.0-4.0
12.0
7.0-8.0
18.8
13.5-14.4
23.6
8%12
50/8
50/7
16/12
23/12
50/5
11/12
43/12
50/9
2/12
21/12
50/12
14/12
8/12
2,6/ 12
15/12
14/12
50/11
EMPIRE LABORATORIES, INC.
SUMMARY OF TEST RESULTS
BORING
DEPTH
%
DRY DENSITY
P.C.F.
UNCONFINED COMPRESSIVE
STRENGTH-P.S.F.
WATER SOLUBLE
SULFATES-%
PENETRATION
BLOWS/INCHES
NO.
FT.
MOISTURE
1
3.0-3.5
14.9
50/6
7.0-7.5
13.9
50/6
13.5-14.0
13.2
50/5
2
3.0-4.0
21.5
10/12
7.0-7.6
14.0
50/7
13.5-14.0
11.9
50/5
3
3.0-4.0
23.5
4/12
7.0-8.0
35.3
12/12
13.5-14.5
17.3
26/12
4
3.0-4.0
27.5
6/12
7.0-8.0
42.9
19/12
13.5-14.5
17.9
26/12
5
3.0-4.0
13.7
7/12
8.5-9.5
24.2
21/12
13.5-14.5
19.5
36/12
EMPIRE
LABORATORIES, INC.
01 Ad
LOG OF BORINGS
F—\//-'� T 10 No. 9 N.. 10 No. I I
4980
4975
4970
4965
4960
4955
2/12
LZ
21112
77-
V
7 --7
15/12
50/7E
r;r—
Id 12
z 10
1
14/12
50/1,
26/L2
' LOG OF BORINGS
1
No. 6 No. 7 No. 8
'
4970
4950
4g55
4g5r
1
t
ll. 12
43/12_
/ ✓
16 12
7112
8 12
23
50 9
e
-o
o.
21 12
— 508
_— 50/5
e
36 12
50/7
49-90
4975
4970
4965
4960
4955
4950
LOG OF BORINGS
J No. I No. 2 No. 3 No. 4-
i,.
7
50 6
—
--
50 5
—
✓ �✓
i
10 12
50 7
_
—
4/12
—
_
— —
6 12
50/5
=
12112
19/12
zz
26/12
26/12
NnTE: ELEVATIONS WERE INTERPOLATED FPO'l
A TOPOGRAPHIC MAP PREPARED RY ZVFK
ARCHITECTS/PLANNERS
KEY TO
BORING
LOGS
TOPSOIL
a
GRAVEL
®
FILL
LA
SAND &GRAVEL
SILT
is
SILTY SAND & GRAVEL
CLAYEY SILT
op
COBBLES
/7'
SANDY SILT
,o�
SAND, GRAVEL & COBBLES
'
®
CLAY
®
WEATHERED BEDROCK
'
FI
SILTY CLAY
PH
SILTSTONE BEDROCK
SANDY CLAY
®
CLAYSTONE BEDROCK
'
a
SAND
SANDSTONE BEDROCK
El
SILTY SAND
®
LIMESTONE
1
�
CLAYEY SAND
""
•
...
GRANITE
'
SHELBY TUBE SAMPLE
STANDARD PENETRATION DRIVE SAMPLER
WATER TABLE 17 DayS
AFTER DRILLING
C
T
HOLECAVED
.i•
.. ♦r iwn Sri._..
_rr
/r ..
i
1
1
17
L
1
1
1
1
1
11
1
TEST BORING LOCATION PLAN
Z
V
_. 1
NN
DITL14 ®No.1`► ® •
No.20
®Na.9
No.16 No.15
0.10
Ne.l7• �Ns.B • •
M/n%R51-1Y /.1RC—/� N0.10 Na.I1 I
Li n.TOT
7 No.11 Na.12 No.13 No.14-
� � J
OQ
` No. Mo. 7
o�C No. S PROP05E.D Df_TLNTION POND I
• • •
No.I Na 2 Ne.3 N&A No.5
••-•DRILLED JUNL 21,22,23, 1972
6---bRILL:LD JUNE— 29 1976 (ALL BORINGS 445r—t)
1
11
II
I
h
U
1
1
the site.
All test holes should be monitored throughout and after instal-
lation of drains and filling of the marsh area to determine the effect
of the construction on groundwater levels in the area and the suita-
bility of the site for basement construction.
GENERAL COMMENTS
Every effort was made to provide comprehensive site coverage
through careful locations of the test borings, while keeping the site
investigation economically feasible. Variations in soil and groundwater
conditions between test borings may be encountered during construction.
In order to permit correlation between the reported subsurface con-
ditions and the actual conditions encountered during construction and to
aid in carrying out the plans and specifications as originally con-
templated, it is recommended that Empire Laboratories, Inc. be retained
to perform continuous construction review during the excavation and
foundation phases of the work. Empire Laboratories, Inc. assumes no
responsibility for compliance with the recommendations included in this
report unless they have been retained to perform adequate on -site
construction review during the course of construction.
1
1
1
1
1
has ceased in the area to the west of the property, and a sewer has been
constructed along the west, south, and east property lines. These
factors have reduced the flow of water into the marsh area slightly.
However, the other factors mentioned above have kept water levels in the
wet area high.
Therefore, to make the marsh area suitable for construction,
alterations in the surface and subsurface drainage in the area will be
required. It is recommended that the marshy area be drained. A series
of drains should be placed below the wet area and should drain to the
south into existing farm drains or into the underdrain below the ex-
isting sewer, if one exists. All vegetation should be stripped from the
wet area, and the marsh should then be filled and graded so that surface
runoff is directed away from the area or into the proposed detention
pond. The drains should be constructed prior to filling the pond.
The subgrade below the pond area should be scarified, if possible,
mixed with a granular pit -run material approved by the soils engineer,
and compacted to at least ninety percent (90%) of Standard Proctor
Density ASTM D 698-70. (See Appendix A.) The pond should then be
filled with a minimum of two (2) feet of the approved granular pit -run
material. Additional fill placed above the pit run may consist of the
on -site clays or other acceptable material approved by the soils engineer.
All fill should be placed in uniform six (6) inch lifts at optimum
moisture and compacted to at least ninety-five percent (95%) of Standard
Proctor Density ASTM D 698-70.
Preparation of subgrade and placement of all fill should be in-
spected by the soils engineer. Field density tests should be taken
under the supervision of the soils engineer to insure proper compaction.
It is further recommended that a drain be placed adjacent to the
Eaton Ditch. The drain should be designed to intercept seepage water
from the ditch and minimize flow into the marsh area and other wet areas
located adjacent to the ditch. Water from the drain should empty into
the proposed detention pond or drain into proposed or existing drains on
I
I
1
1
C
1
1
1
1
11
I
moderate swelling potentials. The upper one-half (2) to three
(3) feet of the bedrock is highly weathered; however, the
underlying interbedded sandstone, siltstone, and claystone is
firm and exhibits very high bearing characteristics.
(6) Groundwater: At the time of the investigation, free ground-
water was encountered at the surface in Boring 2 and to depths
eleven (11) feet below the surface in all but Boring 7. No
free groundwater was encountered in Boring 7 to a depth
fourteen (14) feet below the surface. Water levels in this
area are subject to change due to seasonal variations and
irrigation demands on and adjacent to the site. All test
borings were cased so that water levels could be monitored
throughout the seasonal variations.
RECOMMENDATIONS AND DISCUSSION
It is our understanding that the site is to be developed for
commercial structures, garden apartments, town homes, patio homes, and
single-family homes. A small detention pond is planned in the western
portion of the site.
The western part of the site is currently occupied by a large marsh
or wet area. This area is vegetated with cattails. Groundwater levels
within the marshy area are at or near the surface. The initial investi-
gation for this area, undertaken by Empire Laboratories, Inc. in June
1972, indicated similar groundwater conditions. The marsh is located in
an area of internal drainage and receives surface runoff from the
surrounding land in all directions. Excess irrigation water from
planted fields east of the marsh area drains into the marsh. Seepage
from the Eaton Ditch also flows into the low, wet area.
Surface and groundwater conditions in the area have been altered
somewhat due to construction on and adjacent to the site. Irrigation
(2) Silty Clay: This stratum was encountered in Borings 2, 3, 4,
5, 8, and 11 below the topsoil and extends to depths three
and one-half (32) to twelve and one-half (122) feet below the
surface. The silty clay is very plastic and exhibits low to
moderate bearing characteristics in its dry to moist in situ
condition. When wetted, the drier clays exhibit slight to
moderate swelling potentials.
(3) Sandy Silty Clay: The sandy silty clay layer was encountered
below the topsoil in Borings 1, 6, 7, 9, and 10 and extends to
depths two and one-half (22) to twelve (12) feet below the
surface. The brown silty clay contains varying amounts of
sand and traces of gravel, is plastic, and exhibits moderate
bearing characteristics in its dry to moist natural state.
When wetted, the sandy silty clay exhibits slight to moderate
swelling potentials.
(4) Sand, Gravel, and Cobbles: The granular layer was encountered
in Borings 6 and 7 below the upper clays and extends to depths
ten (10) to greater than fourteen (14) feet below the surface.
The sand and gravel exhibits high bearing characteristics in
its dense in situ condition. It is estimated that the cobbles
within the gravel stratum range in size to twelve (12) inches
in diameter.
(5) Claystone, Siltstone, Sandstone (Bedrock): The bedrock was
encountered in all but Boring 7 at depths two and one-half
(2z) to twelve and one-half (122) feet below the surface and
extends to greater depths. The bedrock consists of inter-
bedded lenses of sandstone, siltstone, and claystone. The
siltstone and claystone portion of the bedrock exhibits
1
1
[1
1
11
11
SITE LOCATION AND DESCRIPTION
The site is located between Redwood Street and Lemay Avenue south
of the Eaton Ditch, northeast of Fort Collins, Colorado. More par-
ticularly, the site is described as Greenbriar P.U.D., situate in the
southeast 1/4 of Section 36, Township 8 North, Range 69 West, and the
north 1/2 of the northeast 1/4 of Section 1, Township 7 North, Range 69
West of the Sixth P.M., Larimer County, Colorado.
The majority of the site consists of relatively flat, irrigated
farm land planted in alfalfa, beans, and corn. A large marshy area
vegetated with cattails and exhibiting high groundwater is located in
the western portion of the site. The Eaton Ditch is located along the
north boundary of the property and is elevated above the site. A small
marshy area is located south of the ditch in the north central portion
of the site. A small hill is located in the northwest corner of the
property, and this portion of the site has good positive drainage from
the knoll to the southwest, south, and southeast. The remainder of the
site has minor drainage to the southeast. A sanitary sewer is located
along the west, south, and east property lines. Large trees are located
in the northern portion of the site along the Eaton Ditch.
SOIL AND GROUNDWATER CONDITIONS
The soil profile at the site consists of strata of materials arranged
in different combinations. In order of increasing depths, they are as
follows:
(1) Silty Topsoil: The area tested is overlain by a one (1) foot
layer of silty topsoil. The upper six (6) inches of the
topsoil have been penetrated by plant roots and organic matter
and should not be used as bearing soil or as backfill material.
I
I
I
II
1
[1
7L
1
I
1
SCOPE
REPORT
OF A
SOIL PROFILE AND GROUNDWATER INVESTIGATION
This report presents the results of a Soil Profile and Groundwater
Investigation prepared for the Greenbriar P.U.D. located on Lemay
Avenue, northeast of Fort Collins, Colorado. The investigation was
carried out by means of test borings and laboratory testing of samples
obtained from these borings.
The objectives of this investigation were to (1) determine the soil
profile and groundwater elevations at the site and (2) recommend certain
precautions which should be taken because of adverse groundwater con-
ditions.
SITE INVESTIGATION
The field investigation, carried out on June 28, 1978, consisted of
drilling, logging, and sampling eleven (11) test borings. The locations
of the test borings are shown on the Test Boring Location Plan included
on page 7 of this report. Boring logs prepared from the field logs are
shown on pages 9 through 11. These logs show soils encountered, lo-
cation of sampling, and groundwater at the time of the investigation.
A preliminary soils and foundation investigation was prepared for the
site by Empire Laboratories, Inc. July 26, 1972. During this investiga-
tion twenty-one (21) test borings, also shown on the Test Boring
Location Plan, were drilled at the site.
All borings were advanced with a four -inch diameter, continuous -
type, power -flight auger drill. During the drilling operations, a
field engineer from Empire Laboratories, Inc. was present and made a
continuous visual inspection of the soils encountered.
G
7
L
Empire Laboratories, Inc.
MATERIALS AND FOUNDATION ENGINEERS
214 No. Howes Fort Collins, Colorado 80522
P.O. Box 429 (303) 484-0359
ZVFK Architect,6 and PZanneas
218 West Mountain Avenue
Font CoUi.nz, CoZorado 80521
Attention: MA. Ed Zdeneh.
Genteemen:
Branch Offices
1242 Bramwood Place
Longmont, Colorado 80501
P.O. Box 1135
(303) 776-3921
3151 Nation Way
Cheyenne, Wyoming 82001
P.O. Box 10076
(307) 632-9224
We cute plea -led to submit ouA Report o6 a So.ie PAo6ite and Groundwater
Inve6tigation prepared 6or the puposed pta.nned unit development .Cocated
nontheaAt ob Font CoZUns, CoZorado, ad requested.
The accompanying report presents ouA jindings in the subsuA�ace and outs
recommendations baaed upon the/se bindings.
Vehy tnuey youX6,
EMPIIRRjE', LABORATORIES, INC. /I
d�
Neil. R. S etucod
S ecttetany-Treas uAeA
Reviewed by:
Chester. C. Smith, P.E.
P)Lu dent
Pit
cc: Resource Con6w tants
Ted Rose
NElI SHERR00
Cy au3'
`0 #2575
n�
J
* N 4SG8
%O(
6 -7
1
V
i
CHESTER C
"` TH
TABLE OF CONTENTS
Table of Contents .......................................... i
Letter of Transmittal ......................................
Report..................................................... 1
Test Boring Location Plan .................................. 7
Key to Borings ............................................. 8
Log of Borings ............................................. 9
Summary of Test Results .................................... 12
AppendixA . ................................................ 14
REPORT
OF A
SOIL PROFILE AND
GROUNDWATER INVESTIGATION
FOR
ZVFK ARCHITECTS AND PLANNERS
FORT COLLINS, COLORADO
PROJECT NO. 1192-72
RE: GREENBRIAR P.U.D.
LAR.IMER COUNTY, COLORADO
BY
EMPIRE LABORATORIES, INC.
214 NORTH HOWES STREET
FORT COLLINS, COLORADO
80521
SOILS
TESTS
ZTI
GROUP
ARCHITECTURE
1220 SC�o Avenue
Fat Cabins, CO 80524
S303 493-4105 Oke
3031 825-1122 Metro