HomeMy WebLinkAbout20101861.tiff 1
CTLITHOMPSON
INCORPONATID
/ •
p
p
p
e •
GEOTECHNICAL INVESTIGATION
CONQUEST OIL C7
WCR 74 AND HIGHWAY 392
BRIGGSDALE, COLORADO
• CGRS, INC.
Box 1489
1301 Academy Court
Fort Collins, Colorado 80522
Attention: Mr. Craig Mulica
• Project Manager - Geologist
Project No. FC03645.021-125
April 1, 2010
•
•
351 Linden Street I Suite 140 I Fort Collins, Colorado 80524
• 2010-1861
Telephone: 970-205-9455 Fax: 970-206-9441
1
• TABLE OF CONTENTS
SCOPE 1
SITE CONDITIONS 2
PROPOSED CONSTRUCTION 2
INVESTIGATION 3
SUBSURFACE CONDITIONS 3
Seismicity 3
SITE DEVELOPMENT 4
Fill Placement 4
Excavation 5
FOUNDATIONS 5
Footings 6
Reinforced Concrete Mat 6
BELOW GRADE AREAS 7
• • FLOOR SYSTEMS 7
PAVEMENTS FOR UNLOADING AREA 9
SURFACE DRAINAGE 11
LIMITATIONS 12
FIGURE 1 - LOCATIONS OF EXPLORATORY BORINGS
FIGURE 2- FIELD BOREHOLE LOG TH-1
• FIGURE 3- FIELD BOREHOLE LOG TH-2
FIGURE 4- FIELD BOREHOLE LOG TH-3
FIGURE 3- SUMMARY LOGS OF EXPLORATORY BORINGS
APPENDIX A- RESULTS OF LABORATORY TESTING
• APPENDIX B-PAVEMENT CONSTRUCTION RECOMMENDATIONS
APPENDIX C - SAMPLE SITE GRADING SPECIFICATIONS
•
•
•
• SCOPE
This report presents the results of our Geotechnical Investigation for the proposed
improvements associated with the Conquest Oil C7 project located northwest of the
intersection of Weld County Road 74 and Highway 392 near Briggsdale, Colorado. The
purpose of the investigation was to evaluate the subsurface conditions and provide
foundation recommendations and geotechnical design criteria for the project.
The report was prepared from data developed during field exploration, laboratory
testing, engineering analysis, and experience with similar conditions. The report
includes a description of subsurface conditions found in exploratory borings observed by
representatives of CGRS, Inc. and discussions of site development as influenced by
• geotechnical considerations. Our opinions and recommendations regarding design
criteria and construction details for foundations, floor systems, slabs-on-grade, lateral
earth loads, pavements, and drainage are provided. If the project grading, building
locations/elevations or proposed construction change, we should be requested to review
▪ • our recommendations contained in this report to determine if they apply to the new
proposed construction. Our opinions are summarized in the following paragraphs. More
complete descriptions of the subsurface conditions, results of our field and laboratory
investigations and our opinions, conclusions and recommendations are included in the
subsequent sections of this report.
SUMMARY OF CONCLUSIONS
✓ 1. Representatives of CGRS, Inc. observed drilling and collected samples
during your field investigation portion of the project. Our Mr. Schram met
with representatives of your firm on-site to observe current conditions and
discuss the field investigation and sampling program for this project. You
delivered field borehole logs as well as soil samples collected during
drilling to our office for laboratory testing.
2. As reported in your boring logs, soils generally consisted of 8 to 10 feet of
silty sand over slightly silty to gravelly sands to the depths explored. A
1.5-foot thick layer of silty clay was found interlayered with the sand in
boring TH-3. Bedrock was not found in our borings. Ground water was
• measured in one boring (TH-3) at a depth of about 18 feet below the
• existing ground surface during drilling. Existing groundwater levels are
not expected to significantly affect the proposed construction.
CGRS,INC. 1
CONQUEST OIL C7
• CTLIT PROJECT NO.FC03645.021-125
• 3. We believe the proposed pre-fabricated metal building can be constructed
on a shallow foundation system consisting of either a footing foundation
or a reinforced mat foundation. We believe the proposed reinforced
containment structure to support the above ground storage tanks can be
constructed on a reinforced mat foundation. Foundation discussion and
criteria for footing and reinforced mat foundations are provided in this
report.
4. If footing foundations are selected for the pre-fabricated metal building,
we believe a slab-on-grade floor is appropriate. Some movement of slab-
on-grade floors should be anticipated. We expect movements will be
minor, on the order of 1 inch or less. If movement cannot be tolerated,
structural floors or a reinforced concrete mat should be considered.
5. The borings drilled in the proposed concrete unloading area penetrated
medium dense silty sand in the upper 8 feet below existing ground
surface. A sample of the silty sand classified as AASHTO A-4 soil, with a
group index of 0. For the unloading pavement, we recommend 7 inches
of portland cement concrete over prepared subgrade.
SITE CONDITIONS
D • The site is located northwest of the intersection of Weld County Road 74 and
Highway 392 near Briggsdale, Colorado (Figure 1). The vacant 11.09±-acre tract is
relatively flat and slopes gently down to the southeast. Ground cover consisted of
natural grasses and weeds. Weld County Road 74 borders the site to the south and
Highway 392 to the southeast. Both roadways were paved with asphaltic concrete. A
dirt road provides access to the eastern portion of the site parallel to Highway 392.
Surrounding parcels were also vacant.
PROPOSED CONSTRUCTION
We understand the proposed construction will consist of a pre-fabricated, single-
story metal building with no below grade area, a reinforced concrete containment
structure to support above ground storage tank(s), and a concrete surfaced unloading
area to provide a hard-surfaced pavement for loading and unloading activities at the site.
No below grade construction is planned. We have assumed very little site grading will
be needed to construct the propose improvements. We also understand the above
•
• ground storage tank(s) will be heavily loaded for the majority of the life of the
containment structure.
CGRS,INC. 2
CONQUEST OIL Cl
• CTL[T PROJECT NO.FC03545.021-125
• INVESTIGATION
Our Mr. Schram met with your representatives on-site to discuss a field
investigation and sampling program. You investigated subsurface conditions at the site
by drilling three borings to depths of 10 to 35 feet below the existing ground surface.
The approximate locations of the borings are shown on Figure 1. Your field
representative observed drilling, logged the soils found in the borings and obtained
samples. Summary logs of the borings, including results of field penetration resistance
tests, are presented on Figures 2 through 4.
You delivered samples obtained during drilling to our laboratory where they were
visually examined by the geotechnical engineer for this project. Laboratory testing
included moisture content, dry density, Atterberg limits, gradation, and water-soluble
sulfate tests. Results of laboratory tests are presented in Appendix A and summarized
on Table A-I.
• SUBSURFACE CONDITIONS
As reported by your boring logs, soils generally consisted of 8 to 10 feet of silty
sand over slightly silty to gravelly sands to the depths explored. A 1.5-foot thick layer of
•
silty clay was found interlayered with the sand in boring TH-3. Bedrock was not found in
the borings. Ground water was measured in one boring (TH-3) at a depth of about 18
feet below the existing ground surface during drilling. Existing groundwater levels are
• not expected to significantly affect the proposed construction. A more complete
description of the subsurface conditions is presented on your boring logs and in our
laboratory testing.
• Seismicity
This area, like most of central Colorado, is subject to a low degree of seismic risk.
As in most areas of recognized low seismicity, the record of the past earthquake activity
• in Colorado is somewhat incomplete.
•
CGRS,INC. 3
CONQUEST OIL C7
• CTL T PROJECT NO.FC03645.021-125
• According to the 2009 International Building Code and the subsurface conditions
encountered in our borings, this site classifies as a Site Class D. Only minor damage to
relatively new, properly designed and built buildings would be expected. Wind loads, not
seismic considerations, typically govern dynamic structural design in this area. A Remi
Survey can be used to determine the shear wave velocities at the site. A survey of this
type may result in a lower seismic site class (Site Class C). However, in our experience
this is unlikely.
SITE DEVELOPMENT
Fill Placement
The existing on-site soils are suitable for re-use as fill material provided debris or
deleterious organic materials are removed. If import material is required, we
recommend importing granular soils for use below reinforced mat foundations or floor
areas. Import fill should contain no particles larger than 3 inches, 10 to 40 percent silt
• and clay-sized particles (percent passing No. 200 sieve) and exhibit a liquid limit less
than 30 and a plasticity index less than 15.
Areas to receive fill should be scarified, moisture-conditioned and compacted to
• at least 95 percent of standard Proctor maximum dry density (ASTM D 698, AASHTO T
99). The properties of the fill will affect the performance of foundations, slabs-on-grade,
and pavements. Sand soils used as fill should be moistened to within 2 percent of
optimum moisture content. The fill should be moisture-conditioned, placed in thin, loose
lifts (8 inches or less) and compacted as described above. Placement and compaction
of fill should be observed and tested by a representative of our firm during construction.
Fill placement and compaction activities should not be conducted when the fill material
or subgrade is frozen.
Site grading in areas of landscaping where no future improvements are planned
can be placed at a dry density of at least 90 percent of standard Proctor maximum dry
density (ASTM D 698, AASHTO T 99). Example site grading specifications are
• presented in Appendix C.
CGRS,INC.
CONQUEST OIL C7 4
CTL T PROJECT NO.FC03645.021-125
• Excavation
The materials found in our borings can be excavated using conventional heavy-
duty excavation equipment. Excavations should be sloped or shored to meet local,
State and Federal safety regulations. Based on our investigation and OSHA standards,
we believe the sand soils classify as Type C soils. Type C soils require a maximum
slope inclination of 1.5:1 (horizontal:vertical) in dry conditions. Excavation slopes
specified by OSHA are dependent upon types of soil and ground water conditions
encountered. The contractor's "competent person" should identify the soils encountered
in the excavation and refer to OSHA standards to determine appropriate slopes.
Stockpiles of soils, rock, equipment, or other items should not be placed within a
horizontal distance equal to one-half the excavation depth, from the edge of excavation.
Excavations deeper than 20 feet should be braced or a professional engineer should
design the slopes. No deep excavations that would require shoring are anticipated at
this time. If plans change, we should be contacted to provide recommendations.
D • Water and sewer lines are often constructed beneath pavement areas.
Compaction of trench backfill can have a significant effect on the life and serviceability of
pavements. We recommend trench backfill be moisture conditioned and compacted as
described above. Placement and compaction of fill and backfill should be observed and
tested by a representative of our firm during construction.
FOUNDATIONS
We believe the proposed pre-fabricated metal building can be constructed on a
shallow foundation system consisting of either a footing foundation or a reinforced mat
foundation. We believe the proposed reinforced containment structure to support the
above ground storage tanks can be constructed on a reinforced mat foundation. We
estimate potential foundation movements of up to 1 inch could occur for foundations
designed and constructed to the criteria below.
Design and construction criteria for footing and reinforced concrete mat
• foundations are provided below. These criteria were developed from analysis of field
and laboratory data and our experience. The recommended foundation alternatives can
CGRS,INC.
CONQUEST OIL C7 5
. CTL T PROJECT NO.FC03645.021-125
• be used provided all design and construction criteria presented in this report are
followed. The builder and structural engineer should also consider design and
construction details established by the structural warrantor (if any) that may impose
additional foundation design and installation requirements.
1
Footings
1. Footings should be constructed on undisturbed natural soils or properly
compacted fill. Where soil is loosened during excavation, it should be
/ removed and replaced with on-site soils compacted following the criteria
in the Fill Placement section of this report.
2. Footings constructed on the natural soils and/or properly compacted fill
can be designed for a net allowable soil pressure of 3,000 psf. The soil
pressure can be increased 33 percent for transient loads such as wind or
1 seismic loads.
3. Footings should have a minimum width of at least 16 inches.
Foundations for isolated columns should have minimum dimensions of 24
inches by 24 inches. Larger sizes may be required depending on loads
• and the structural system used.
4. The soils beneath footing pads can be assigned an ultimate coefficient of
friction of 0.55 to resist lateral loads. The ability of grade beams, or
footing backfill to resist lateral loads can be calculated using a passive
equivalent fluid pressure of 300 pcf. This assumes the backfill is densely
compacted and will not be removed. Backfill should be placed and
compacted to the criteria in the Fill Placement section of the report.
5. Exterior footings should be protected from frost action. We believe 30
inches of frost cover is appropriate for this site.
6. Foundation walls and grade beams should be well reinforced both top
and bottom.
7. We should be retained to observe the completed footing excavations to
confirm that the subsurface conditions are similar to those found in your
borings. Occasional loose soils may be found in foundation excavations.
• If this occurs, we recommend the loose soils be treated as discussed in
Item 1 above.
Reinforced Concrete Mat
1. The reinforced concrete mat foundation should be designed for a net
allowable soil pressure of 3,000 psf. The soil pressure can be increased
•
33 percent for transient loads such as wind or seismic loads.
CGRS,INC. 6
CONQUEST OIL C7
CTL T PROJECT NO.FC03645.021-125
• 2. Reinforced slabs are typically designed using a modulus of subgrade
recommend use of a modulus of 400 pounds per square inch per inch of
deflection (pci).
3. The soils beneath footing pads can be assigned an ultimate coefficient of
friction of 0.55 to resist lateral loads. The ability of grade beams, or
footing backfill to resist lateral loads can be calculated using a passive
equivalent fluid pressure of 300 pcf. This assumes the backfill is densely
compacted and will not be removed. Backfill should be placed and
compacted to the criteria in the Fill Placement section of the report. A
moist unit weight of 135 pcf can be assumed for natural soils and
compacted fill. These values are considered ultimate values and
appropriate factors of safety should be used. Typically, a factor of safety
of 1.5 is used for sliding and 1.6 for lateral earth pressure.
4. The edges of the mats should be thickened or turned down for structural
strength.
5. Materials beneath the mat foundation should be protected from frost
action. We believe 30 inches of frost cover is appropriate for this site.
6. We should be retained to observe the completed excavations for mats to
confirm that the subsurface conditions are similar to those found in your
D • borings.
BELOW GRADE AREAS
No below grade areas are planned for the pre-fabricated metal building or the
reinforced concrete containment structure. For this condition, perimeter drains are not
usually necessary used around the structures. We should be contacted to provide
foundation drain recommendations if plans change to include basement areas.
I
FLOOR SYSTEMS
If a reinforced concrete mat foundation is selected for the pre-fabricated metal
6 building, the floor will be integral with the foundation system. If a footing foundation is
selected for the pre-fabricated metal building, we believe a slab-on-grade floor can be
used. The subgrade for the slab-on-grade floor will be the natural silty sands and/or
properly compacted fill needed to achieve the desired subgrade elevations. Laboratory
test results indicate the silty sands are non-expansive.
•
CGRS,INC.
CONQUEST OIL C7 7
CTL T PROJECT NO.FC03645.021-125
• It is impossible to construct slab-on-grade floors with no risk of movement. We
believe movements will be less than 1 inch at this site. If movement cannot be tolerated,
structural floors or a reinforced concrete mat foundation should be used for the pre-
fabricated metal building. The level of risk acceptable to the owner should be
considered when selecting the floor system.
Where structurally supported floors are selected, we recommend a minimum void
between the ground surface and the underside of the floor system of 6 inches. The
minimum void should be constructed below beams and utilities that penetrate the floor.
The floor may be cast over void form. Void form should be chosen to break down
quickly after the slab is placed. We recommend against the use of wax or plastic-coated
void boxes.
1
If the owner elects to use slab-on-grade construction and accepts the risk of
movement and associated damage, we recommend the following precautions for slab-
on-grade construction at this site. These precautions can help reduce, but not eliminate
1 • damage or distress due to slab movement.
1. Slabs should be separated from exterior walls and interior bearing
members with a slip joint that allows free vertical movement of the slabs.
This can reduce cracking if some movement of the slab occurs.
2. Slabs should be placed directly on exposed soils or properly moisture
conditioned, compacted fill. The 2009 International Building Code (IBC)
requires a vapor retarder be placed between the base course or subgrade
soils and the concrete slab-on-grade floor. The merits of installation of a
vapor retarder below floor slabs depend on the sensitivity of floor
coverings and building use to moisture. A properly installed vapor
retarder (10 mil minimum) is more beneficial below concrete slab-on-
grade floors where floor coverings, painted floor surfaces or products
stored on the floor will be sensitive to moisture. The vapor retarder is
most effective when concrete is placed directly on top of it, rather than
placing a sand or gravel leveling course between the vapor retarder and
the floor slab. The placement of concrete on the vapor retarder may
increase the risk of shrinkage cracking and curling. Use of concrete with
reduced shrinkage characteristics including minimized water content,
maximized coarse aggregate content, and reasonably low slump will
. reduce the risk of shrinkage cracking and curling. Considerations and
• recommendations for the installation of vapor retarders below concrete
slabs are outlined in Section 3.2.3 of the 2006 report of American
CGRS,INC.
CONQUEST OIL C7
CTL T PROJECT NO.FC03645.021-125
• Concrete Institute (ACI) Committee 302, "Guide for Concrete Floor and
Slab Construction (ACI 302.R1-04)".
3. If slab-bearing partitions are used, they should be designed and
constructed to allow for slab movement. At least a 1.5-inch void should
be maintained below or above the partitions. If the "float" is provided at
the top of partitions, the connection between interior, slab-supported
partitions and exterior, foundation supported walls should be detailed to
allow differential movement.
4. Underslab plumbing should be eliminated where feasible. Where such
plumbing is unavoidable it should be thoroughly pressure tested for leaks
prior to slab construction and be provided with flexible couplings.
Pressurized water supply lines should be brought above the floors as
quickly as possible.
5. Plumbing and utilities that pass through the slabs should be isolated from
the slabs and constructed with flexible couplings. Where water and gas
lines are connected to furnaces or heaters, the lines should be
constructed with sufficient flexibility to allow for movement.
6. HVAC equipment supported on the slab should be provided with a
collapsible connection between the furnace and the ductwork, with
• allowance for at least 1.5 inches of vertical movement.
p
7. The American Concrete Institute (ACI) recommends frequent control
joints be provided in slabs to reduce problems associated with shrinkage
cracking and curling. To reduce curling, the concrete mix should have a
high aggregate content and a low slump. If desired, a shrinkage
compensating admixture could be added to the concrete to reduce the
risk of shrinkage cracking. We can perform a mix design or assist the
design team in selecting a pre-existing mix.
PAVEMENTS FOR UNLOADING AREA
•
One boring was drilled for the proposed unloading area. Laboratory tests on
selected samples indicated the subgrade will consist of silty sand that generally
classifies as AASHTO category A-4 with a group index of 0. If imported fill is needed to
achieve desired grades, we have assumed it will be soils with similar characteristics.
We used the group index approach to estimate the support characteristics of the
anticipated subgrade in our design calculations.
We understand heavily loaded trucks and unique materials handling equipment
• will be trafficking the unloading pavement. Our designs are based on the AASHTO
CORS,INC. 9
CONQUEST OIL C7
CTL T PROJECT NO.FC03645.021-125
• design method and our experience. For design calculations, we assumed an Equivalent
Single-Axel Load (ESAL) of 365,000 would be appropriate for this site. We should be
contacted if our assumptions for traffic loading conditions for the unloading area are not
accurate to review our pavement thickness design.
1
Using the criteria discussed above we recommend the minimum pavement
sections provided in Table C.
TABLE C
1 RECOMMENDED PAVEMENT SECTIONS
Unloading Area 7.0"
Our experience indicates rigid portland cement concrete pavements generally
perform better than asphalt pavements in areas where trucks stop and maneuver at slow
D • speeds as is the case for the unloading areas of this site. We do not recommend using
asphaltic concrete for the unloading area pavements.
Design of the pavement section is a function of paving materials and support
characteristics of the subgrade. The quality of paving materials is reflected in the
structural coefficients we used in the above evaluation. If the pavement is constructed of
inferior material, then its serviceability and life will be reduced. Criteria for pavement
materials and construction are presented in Appendix B.
Our firm should be retained to carry out construction control and observations
during subgrade preparation and paving operations. Concrete should be carefully
monitored for quality control. To avoid problems associated with scaling and to continue
strength gain, we recommend deicing salts not be used the first year after placement.
The primary cause of premature pavement deterioration is infiltration of water
into the pavement system. This increase in moisture content usually results in the
•
• softening of subgrade soils and eventual failure of the pavement. We recommend
pavements and surrounding ground surface be sloped to cause surface water to rapidly
CGRS,INC. t 0
CONQUEST OIL C7
• CTL T PROJECT NO.FC03645.021-125
• run off and away from pavements. The final grading of the subgrade should be carefully
controlled so the pavement design cross-section can be maintained. Low spots in the
subgrade that can trap water should be eliminated. Seals should be provided in all joints
to reduce the possibility of water infiltration.
WATER-SOLUBLE SULFATES
Concrete that comes into contact with soils can be subject to sulfate attack. We
measured water-soluble sulfate concentrations in two samples from this site.
Concentrations were measured between 0.01 and 0.07 percent. Sulfate concentrations
less than 0.1 percent indicate Class 0 exposure to sulfate attack for concrete that comes
into contact with the subsoils, according to the American Concrete Institute (ACI). For
1 this level of sulfate concentration, ACI indicates any type of cement can be used for
concrete that comes into contact with the soils and/or bedrock. In our experience,
superficial damage may occur to the exposed surfaces of highly permeable concrete,
even though sulfate levels are relatively low. To control this risk and to resist freeze-
thaw deterioration, the water-to-cementitious material ratio should not exceed 0.50 for
concrete in contact with soils that are likely to stay moist due to surface drainage or high
water tables. Concrete should be air entrained.
SURFACE DRAINAGE
Performance of pavements, flatwork and foundations are influenced by changes
in subgrade moisture conditions. Carefully planned and maintained surface grading can
reduce the risk of wetting of the foundation soils and pavement subgrade. We
recommend the following precautions be observed during and maintained after the
completion of the proposed construction:
1. Wetting or drying of the open foundation excavations should be avoided.
2. Positive drainage should be provided away from foundations. We
recommend a minimum slope of at least 5 percent in the first 10 feet
away from the foundations in landscaped areas, where possible.
Pavements and sidewalks adjacent to the building should be sloped for
• positive drainage away from the building. Water should not be allowed to
pond on pavements.
CGRS,INC. 11
CONQUEST OIL C7
. CTL T PROJECT NO.FC03645.021-125
• 3. Backfill around foundations should be moisture treated and compacted as
described in the Fill Placement section of this report.
4. Roof drains should be directed away from the structures. Downspout
extensions and splash blocks should be provided at discharge points.
Where downspouts discharge onto pavement and aggregate-surfaced
» parking areas, the pavement or aggregate-surfaced parking areas should
be sloped away from the structures.
5. Landscaping should be carefully designed to minimize irrigation.
Irrigation should not be located within 5 feet of the foundations.
Sprinklers should not discharge within 5 feet of foundations. Irrigation
should be limited to the minimum amount sufficient to maintain
vegetation; application of more water will increase likelihood of slab and
foundation movements.
6. Impervious plastic membranes should not be used to cover the ground
surface immediately surrounding the structures. These membranes tend
to trap moisture and prevent normal evaporation from occurring.
Geotextile fabrics can be used to limit weed growth and allow for
evaporation.
. LIMITATIONS
Although the borings were spaced to obtain a reasonably accurate picture of
subsurface conditions, variations not indicated in the borings are always possible. We
should be retained to observe footing excavations to confirm soils are similar to those
•
found in our borings. We should also be retained to observe and test placement and
compaction of fill, backfill, subgrade, and other fills during construction.
• This report was prepared from data developed during your field exploration,
laboratory testing, engineering analysis and experience with similar conditions. The
recommendations contained in this report were based upon our understanding of the
planned construction. If plans change or differ from the assumptions presented herein,
• we should be contacted to review our recommendations.
We believe this investigation was conducted in a manner consistent with that
level of skill and care ordinarily used by members of the profession currently practicing
• under similar conditions in the locality of this project. No warranty, express or implied, is
• made.
CGRS,INC. t 2
CONQUEST OIL Cl
• CTL T PROJECT NO.FC03645.021-125
• If we can be of further service in discussing the contents of this report or in the
analysis of the structures and pavement from the geotechnical point of view, please
contact the undersigned.
•••................
....LICE
CTL I TROMPS S �'✓ cP°.
oto
O1
Eric D. Bernhardt, , \/oN a •✓o'
Project Manager 'b....,,...••°
" RFG
Reviewed by: ,,c � ,/r>�,,
. u ,
R. B. "Chip f adtfetter, II w
Division Ma 4 y Pb p�
u
•
•
•
•
r
CGRS,INC. 1.3
CONQUEST OIL C7
• CTL T PROJECT NO.FC03645.021-125
I
III!
431111)
• HWY 14
Briggsdale
APPROXIMATE
SCALE: 1"=150' S
0' 75' 150' re SITE S u i'e
CRnoses eat -74 r
Galeton
II HWY 392
LEGEND: VICINITY MAP
(WELD COUNTY,CO)
NOT TO SCALE
TH-1 INDICATES APPROXIMATE
• LOCATION OF EXPLORATORY
i BORING
•ants . ion 021
r • TH-3 t �. -
I . TH1 . /T
e TH-2 I 11.09 e acquired)
��—�
e (Site to be acquired)
• . L - - ._ _ .__ J._-- .
04
. - - `t
/ /
oo.wr..w-ra F.r.e....e.r u.0
. -- r,.r�- - -/---—ti—
__ _ s 075„o: • 506.25'• _. - A' . •
A 7.
Locations of
• Exploratory
all Borings
CGRS,INC FIGURE 1
CONQUEST OIL C7
• CTL I T PROJECT NO.FC03645.021-125
II
CGRS FIELD BOREHOLE LOG BOREHOLE NUMBER
TH-1
*CT NUMBER: 1-8019-12439aa TOTAL DEPTH: 10'
PROJECT NAME: Conquest Oil C-7 TOP OF RISER:-
(with cap removed)
LOCATION: Briggsdale, CO
STATIC WATER LEVELS(BGS)
DRILLING CO: Drilling Engineers, Inc.
DRILLING METHOD: HSA Time
DRILLER: Sean Date
LOGGED BY: TJ Grisel Water Level
START: 3/18/2010 COMPLETED: 3/18/2010 Casing Depth
i d
c
au
s' To
2 'o
Notes LITHOLOGY
a. 3 a) DEPTH DESCRIPTION
I— z a 5 IY (PPm)
a) a> § a) a)
es E
as cag E (i3co com co co
—0 - .
SANDY SILT: Brown, fine to _ _ _ill very fine-grained, stiff, moist —
• (SM)
CAL 1 15 18 18 0.0 @ 2' bgs II -CAL 2 21 18 18 0.0 @ 4' bgs _-_ . _.
--5 __
SAND: Brown,fine to medium-
grained, sub-angular, medium
_ dense, moist(SW) ,
• CAL 3 16 18 18 0.0 @ 9 bgs
0 — -10 .•.•.•.•.•.•.•.•.•..•.•.•.
•
1 End of Boring @ 10 bgs /
CGRS,INC.
CONQUEST OIL C7
• CTLIT PROJECT NO.FC03645.021-125 FIGURE 2
C G FIELD BOREHOLE LOG BOREHOLE NUMBER
TH-2
•CT NUMBER: 1-8019-12439aa TOTAL DEPTH: 25'
D PROJECT NAME: Conquest Oil C-7 TOP OF RISER:-
(with cap removed)
LOCATION: Briggsdale, CO STATIC WATER LEVELS (BGS)
DRILLING CO: Drilling Engineers, Inc. .
DRILLING METHOD: HSA Time
' DRILLER: Sean Date
LOGGED BY: TJ Grisel Water Level
START: 3/18/2010 COMPLETED: 3/18/2010 Casing Depth
L..
a)
Z o Notes LITHOLOGY
z IY DEPTH DESCRIPTION (ppm)
a) w a a� wU
15.
E 8 E E
—0 F
SANDY SILT: Brown,fine to - - -
very fine-grained, very stiff, _
0 _ moist(SM) - __
CAL 1 30 18 18 -_ - - =
--5 0.0@5'bgs . .._—
CAL 2 36 18 18 -- -
—-10 SAND: Brown, fine to medium- 0.0 @ 10'bgs
-
grained, sub-angular, very
- dense, moist to wet @ 15' bgs
• - to saturated @ 20'bgs; No
_ Recovery @ 20'bgs(SW)
CAL 3 45 18 18
-15 0.0@15'bgs
CAL 4 50+ 18 0 --20
NM @ 20' bgs
• - ..... .........
5 50+ 18 4 0.0 @ 25' bgs
-25
End of Boring @ 25' bgs
/
CGRS,INC.
CONQUEST OIL C7
• CTLIT PROJECT NO.FC03645.021-125 FIGURE 3
CGRS FIELD BOREHOLE LOG BOREHOLE NUMBER
TH-3
•JECT NUMBER: 1-8019-12439aa TOTAL DEPTH : 30'
ll PROJECT NAME : Conquest Oil C-7 TOP OF RISER :-
(with cap removed)
LOCATION : Briggsdale, CO
DRILLING CO: Drilling Engineers, Inc. STATIC WATER LEVELS(BGS)
DRILLING METHOD : NSA Time 0950 1050 1239
DRILLER: Sean Date 3/18/2010 3/18/2010 3/18/2010
LOGGED BY:TJ Grisel Water Level 20.90 20.84 20.82
START: 3/18/2010 COMPLETED : 3/18/2010 Casing Depth 32.25
c
•cu }
a) .n Ii
NOTES WELL WELL
(:).
z DESCRIPTION (ppm) p DESIGN CONSTRUCTION
m w Q w CI) I I
J
E E O E E I,7
O rco � m ro ro p
v7 6
Stick-Up(-3
- ft)
IP • -0 -
SANDY SILT:Gray,fine-grained, a}; 47-4;-
stiff,moist(SM) _- ''i re
CAL 1 18 24 9 -5 "'=_= `= �=
0.0@5'bgs
-
CAL 2 18 24 3 - -- — "
SAND: Brown,fine to medium
_ grained,sub-angular,medium- "'` :mt.`'
+ _ dense,moist to very moist @ 14' "' `
bgs Natural '., M
CAL 3 15 24 7 ; Backfill . :,,..r,
4`
-15 0.0 15'
-- @ is
SILTY CLAY:Wet,brown,rather
`stiff,some fine sand(CL) bgs;Sa pledfo :TO ;
-
Retained for
- SAND: Brown,fine to medium-
Analysis
• CAL 4 50+ 24 0 grained,sub-angular, medium
-20 dense to very dense;wet to NM @ 20'bgs
1"Sch.40
- saturated @ 20'bgs; No recovery : PVC Riser
@ 20' bgs : 10/20 Silica•
:
- Sand filter
CAL 5 50+ 24 21 ::::•:::::::::::::
41 --2
0.0 @ 25'bgs r TiT T-- _ 1"Schedule
SILTY SAND: Brown,fine-grained, TV.T+T 7-17 T= 40 PVC
• = sub-angular,very dense, T T-'1-' screen#10
T' T T..
saturated(SM) T T 71-T.T. slot
T T.T.7-r
T.
'71-T T.T.:
CAL 6 50+ 24 24 0.0@30'bgs rTT-rT ...
CGRS,INC. --3 I
CONQUEST OIL C7 End of Boring @ 30'bgs /
• CTLIT PROJECT NO.FC03645. -1[o FIGURE 4
•
r
I
APPENDIX A
RESULTS OF LABORATORY TESTING
• •
•
•
•
•
•
III
0
III HYDROMETER ANALYSIS 1 SIEVE ANALYSIS
25 HR. 7 HR. TIME READINGS U.S.STANDARD SERIES CLEAR SQUARE OPENINGS
45 MIN. 15 MIN. 60 MIN. 19 MIN. 4 MIN. 1 MIN. '200 '100 '50 '40 '30 '18 '10'8 '4 3/8' 3/4' 1W 3" 5'6" 8'
100 _ - __ - -• -- -0
90 - -- 10
80 • ___.-- 0
•
•
2• •
30 w
_
40 w
• • • •
H
z • : .. - 0 w
U.1 50 ---' _. .. —
cc
_ U
•
10 -90
'
I, 127.001 0.002 .005 .009 .019 .037 .074 .149-•-.297 .590 1.19 2.0 2.38 4.76 9.52 19.1 36.1 76.2
200
0.42 152
DIAMETER OF PARTICLE IN MILLIMETERS
SANDS GRAVEL
CLAY(PLASTIC)TO SILT(NON-PLASTIC) FINE I MEDIUM I COARSE FINE I COARSE I COBBLES
Sample of SAND,SILTY(SC-SM) GRAVEL 1 % SAND 60 %
From TH- 1 AT 2 FEET SILT&CLAY 39 % LIQUID LIMIT 20
` •
PLASTICITY INDEX 6
I HYDROMETER ANALYSIS I SIEVE ANALYSIS
25 HR. 7 HR. TIME READINGS U.S.STANDARD SERIES CLEAR SQUARE OPENINGS
45 MIN. 15 MIN. 60 MIN. 19 MIN. 4 MIN. 1 MIN. '200 '100 '50 '40 '30 '16 '10'8 '4 3/8' 3/4' 1'h' 3' 5'8' 8'0
100 -. -_ - _ ..0 - 0
so -..
— r
1
80 _..... -_,--
,. .._.._ _ . ---- 30 C?
C7 70 -
_. __ _
a 60 —._
. _ . .. .
: . z
50
w
a 40 • • --. _._
.- 70
.001 0.002 .005 009 .019 .037 .074 .149 .297 0 42 590 1.19 2 0 2.38 4.78 9.52 19.1 36.1 76.2 127522
DIAMETER OF PARTICLE IN MILLIMETERS
SANDS GRAVEL
CLAY(PLASTIC)TO SILT(NON-PLASTIC) FINE I MEDIUM I COARSE FINE I COARSE 1 COBBLES
• Sample of SAND, SILTY(SM) GRAVEL 0 % SAND 77 %
From TH-2 AT 4 F_EET SILT&CLAY 23 % LIQUID LIMIT
PLASTICITY INDEX
Gradation
• CGRS,INC. Test Results
CONQUEST OIL C7
CTL I T PROJECT NO.FC03645.021-125
FIGURE A-1
II
T
• HYDROMETER ANALYSIS SIEVE ANALYSIS
25 HR. 7 HR. TIME READINGS U.S.STANDARD SERIES CLEAR SQUARE OPENINGS
45 MIN. 15 MIN. 60 MIN. 19 MIN. 4 MIN. 1 MIN. '200 '100 '50 *40 '30 '16 '10 '8 '4 3/8' 3/4" Ph' 3' 5"6" 8'
100 --- __ _____ __ __._ 0
::__ 10
•
ID 80 - -- __ '_ - _ 20
070 - - _. 30 Z 0.< 60 -_ . _ 40 w
U50 _-5p
cc
40 - __ __ L --60 d
30 .---- -70
20 _._ f _.80
i.
10 _ .. _: ... ._ L---90
•
.001 0.002 005 008 - L
019 03] .074 .149 j 29] 042590 1.19 20 236 4.76 9.52 19.1 361 1-�76 100
2 127 200
152
DIAMETER OF PARTICLE IN MILLIMETERS
SANDS GRAVEL
CLAY(PLASTIC)TO SILT(NON-PLASTIC)
FINE I MEDIUM I COARSE FINE I COARSE I COBBLES
Sample of SAND, SLIGHTLY SILTY(SP-SM) GRAVEL 27 % SAND 63 %
From TH -2 AT 14 FEET SILT&CLAY 10 % LIQUID LIMIT
▪ • - PLASTICITY INDEX
HYDROMETER ANALYSIS SIEVE ANALYSIS
25 HR. 7 HR. TIME READINGS U.S.STANDARD SERIES CLEAR SQUARE OPENINGS
45 MIN. 15 MIN. 60 MIN. 19 MIN. 4 MIN. 1 MIN. '200 '100 '50 '40 '30 '16 '10 '8 '4 3/8' 3/4' 1'h' 3' 5"6" 8'0
100 ___. __ ___ ---_• 90 :_... __. _.. _. _ ..._._. :___10
80 1
z - _ :_I z
a 60 __— _. J _ ._.. __
cr
• W 50 _.. .. 'i 50 w
c..,
LC
do0 _..: -. . _60 a
30 _.. .. _ 70
__-_ 80
di
10 _. . .. . _ ___ -_ 90
_ 100
O01 0 002 .005 .009 019 -.037 074 .149 .297 0.42 590 1.19 2.0 2.38 4.76 9 52 19.1 36.1 ]fi.2 127
200
15
2
DIAMETER OF PARTICLE IN MILLIMETERS
SANDS GRAVEL
CLAY(PLASTIC)TO SILT(NON-PLASTIC)
• FINE I MEDIUM ICOARSE FINE I COARSE I COBBLES
• Sample of SAND, GRAVELLY(SP) GRAVEL 29 % SAND 66
From TH -3 AT 9 FEET SILT&CLAY 5 % LIQUID LIMIT
0/0
PLASTICITY INDEX
Gradation
• CONS NC. Test Results
CONQUEST OIL C7
CTL I T PROJECT NO.FC03645.021-125
FIGURE A-2
• • • • • • • • • or •
• • s
TABLE A-I
SUMMARY OF LABORATORY TESTING
ATTERBERG LIMITS PASSING AASHTO
MOISTURE DRY LIQUID PLASTICITY NO. 200 SOLUBLE CLASSIFICATION
DEPTH CONTENT DENSITY LIMIT INDEX SIEVE SULFATES (GROUP
BORING (FEET) (%) (PCF) (%) (%) INDEX) DESCRIPTION
TH-1 2 5.2 20 6 38.5 A-4 (0) SAND, SILTY (SC-SM)
TH-1 4 2.8 0.07 SAND, SILTY (SM)
TH-2 4 4.5 23.3 SAND, SILTY (SM)
TH-2 14 5.5 10.0 SAND, SLIGHTLY SILTY (SP-SM)
TH-3 4 3.2 0.01 SAND, SILTY (SM)
TH-3 9 1.7 5.0 SAND, GRAVELLY (SP)
CGRS,INC.
CONQUEST OIL C7
CTLIT PROJECT NO.FC03645.021-125 Page 1 of 1
p
p
p
APPENDIX B
PAVEMENT CONSTRUCTION RECOMMENDATIONS
D0
p
S
S
S
S
• PAVEMENT CONSTRUCTION RECOMMENDATIONS
I
Moisture Treated Subgrade (MTS)
1. The subgrade should be stripped of organic matter, scarified, moisture
treated and compacted to the specifications stated below in Item 2. The
compacted subgrade should extend at least 3 feet beyond the edge of the
pavement where no edge support, such as curb and gutter, are to be
constructed.
2. Sandy and gravelly soils should be moisture conditioned near optimum
moisture content and compacted to at least 95 percent of standard
Proctor maximum dry density (ASTM D 698, AASHTO T 99).
3. Utility trenches and all subsequently placed fill should be properly
compacted and tested prior to paving. As a minimum, fill should be
compacted to 95 percent of standard Proctor maximum dry density.
4. Final grading of the subgrade should be carefully controlled so the design
cross-slope is maintained and low spots in the subgrade that could trap
water are eliminated.
5. Once final subgrade elevation has been compacted and tested to
compliance and shaped to the required cross-section, the area should be
• • proof-rolled using a minimum axle load of 18 kips per axle. The proof-roll
should be performed while moisture contents of the subgrade are still
within the recommended limits. Drying of the subgrade prior to proof-roll
or paving should be avoided.
. 6. Areas that are observed by the Engineer that have soft spots in the
subgrade, or where deflection is not uniform of soft or wet subgrade shall
be ripped, scarified, dried or wetted as necessary and recompacted to the
requirements for the density and moisture. As an alternative, those areas
may be sub-excavated and replaced with properly compacted structural
backfill. Where extensively soft, yielding subgrade is encountered; we
recommend a representative of our office observe the excavation.
Portland Cement Concrete (PCC)
1. Portland cement concrete should consist of Class P of the 2005 CDOT -
' Standard Specifications for Road and Bridge Construction specifications
for normal placement or Class E for fast-track projects. PCC should have
a minimum compressive strength of 4,200 psi at 28 days and a minimum
modulus of rupture (flexural strength) of 600 psi. Job mix designs are
recommended and periodic checks on the iob site should be made to
verify compliance with specifications.
S
• 2. Portland cement should be Type II "low alkali" and should conform to
ASTM C 150.
B-1
CGRS,INC.
CONQUEST OIL C7
• CTL T PROJECT NO.FC03645.021-125
• 3. Portland cement concrete should not be placed when the subgrade or air
temperature is below 40°F.
4. Concrete should not be placed during warm weather if the mixed concrete
has a temperature of 90°F, or higher.
5. Mixed concrete temperature placed during cold weather should have a
temperature between 50°F and 90°F.
6. Free water should not be finished into the concrete surface. Atomizing
nozzle pressure sprayers for applying finishing compounds are
recommended whenever the concrete surface becomes difficult to finish.
7. Curing of the portland cement concrete should be accomplished by the
use of a curing compound. The curing compound should be applied in
accordance with manufacturer recommendations.
8. Curing procedures should be implemented, as necessary, to protect the
pavement against moisture loss, rapid temperature change, freezing, and
mechanical injury.
9. Construction joints, including longitudinal joints and transverse joints,
should be formed during construction or sawed after the concrete has
begun to set, but prior to uncontrolled cracking.
II • 10. All joints should be properly sealed using a rod back-up and approved
epoxy sealant.
11. Traffic should not be allowed on the pavement until it has properly cured
and achieved at least 80 percent of the design strength, with saw joints
already cut.
We should be retained to observe and test portland cement concrete during placement.
Placement should not commence until the subgrade is properly prepared and tested.
S
S
•
B-2
CGRS,INC.
CONQUEST OIL C7
• CTL T PROJECT NO.FC03645.021-125
I •
I
I
APPENDIX C
SAMPLE SITE GRADING SPECIFICATIONS
P
I
I
S
S
• SAMPLE SITE GRADING SPECIFICATIONS
1. DESCRIPTION
This item shall consist of the excavation, transportation, placement and compaction of
materials from locations indicated on the plans, or staked by the Engineer, as necessary
to achieve building site elevations.
2. GENERAL
The Soils Engineer shall be the Owner's representative. The Soils Engineer shall
approve fill materials, method of placement, moisture contents and percent compaction,
and shall give written approval of the completed fill.
3. CLEARING JOB SITE
The Contractor shall remove all trees, brush and rubbish before excavation or fill
placement is begun. The Contractor shall dispose of the cleared material to provide the
Owner with a clean, neat appearing job site. Cleared material shall not be placed in
areas to receive fill or where the material will support structures of any kind.
4. SCARIFYING AREA TO BE FILLED
• All topsoil and vegetable matter shall be removed from the ground surface upon which
fill is to be placed. The surface shall then be plowed or scarified to a depth of 8 inches
until the surface is free from ruts, hummocks or other uneven features, which would
prevent uniform compaction by the equipment to be used.
5. COMPACTING AREA TO BE FILLED
After the foundation for the fill has been cleared and scarified, it shall be disked or
bladed until it is free from large clods, brought to the proper moisture content and
compacted to not less than 95 percent of maximum dry density as determined in
accordance with ASTM D 698 or AASHTO T 99.
6. FILL MATERIALS
On-site materials classifying as CL, SC, SM, SW, SP, GP, GC, and GM are acceptable.
Fill soils shall be free from organic matter, debris, or other deleterious substances, and
shall not contain rocks or lumps having a diameter greater than three (3) inches. Fill
• materials shall be obtained from the existing fill and other approved sources.
7. MOISTURE CONTENT
Fill materials shall be moisture treated. Sand soils can be moistened to within 2 percent
• of optimum moisture content. Sufficient laboratory compaction tests shall be performed
to determine the optimum moisture content for the various soils encountered in borrow
•
areas.
CGRS,INC. C-1
CONQUEST OIL C7
• CTL T PROJECT NO.FC03645.021-125
•
The Contractor may be required to add moisture to the excavation materials in the
borrow area if, in the opinion of the Soils Engineer, it is not possible to obtain uniform
moisture content by adding water on the fill surface. The Contractor may be required to
rake or disk the fill soils to provide uniform moisture content through the soils.
The application of water to embankment materials shall be made with any type of
watering equipment approved by the Soils Engineer, which will give the desired results.
Water jets from the spreader shall not be directed at the embankment with such force
that fill materials are washed out.
Should too much water be added to any part of the fill, such that the material is too wet
to permit the desired compaction from being obtained, rolling and all work on that section
of the fill shall be delayed until the material has been allowed to dry to the required
moisture content. The Contractor will be permitted to rework wet material in an
approved manner to hasten its drying.
8. COMPACTION OF FILL AREAS
Selected fill material shall be placed and mixed in evenly spread layers. After each fill
layer has been placed, it shall be uniformly compacted to not less than the specified
percentage of maximum dry density. Fill materials shall be placed such that the
thickness of loose material does not exceed 8 inches and the compacted lift thickness
does not exceed 6 inches.
• • Compaction, as specified above, shall be obtained by the use of sheepsfoot rollers,
multiple-wheel pneumatic-tired rollers, or other equipment approved by the Engineer.
Compaction shall be accomplished while the fill material is at the specified moisture
content. Compaction of each layer shall be continuous over the entire area.
Compaction equipment shall make sufficient trips to insure that the required dry density
is obtained.
9. COMPACTION OF SLOPES
Fill slopes shall be compacted by means of sheepsfoot rollers or other suitable
equipment. Compaction operations shall be continued until slopes are stable, but not
ID too dense for planting, and there is no appreciable amount of loose soil on the slopes.
Compaction of slopes may be done progressively in increments of three to five feet (3' to
5') in height or after the fill is brought to its total height. Permanent fill slopes shall not
exceed 3:1 (horizontal to vertical).
10. DENSITY TESTS
Field density tests shall be made by the Soils Engineer at locations and depths of his
choosing. Where sheepsfoot rollers are used, the soil may be disturbed to a depth of
several inches. Density tests shall be taken in compacted material below the disturbed
surface. When density tests indicate that the dry density or moisture content of any
layer of fill or portion thereof is below that required, the particular layer or portion shall be
• reworked until the required dry density or moisture content has been achieved.
CGRS,INC. C-2
CONQUEST OIL C7
CTLIT PROJECT NO.FC03645.021-125
• 11. COMPLETED PRELIMINARY GRADES
All areas, both cut and fill, shall be finished to a level surface and shall meet the
following limits of construction:
A. Overlot cut or fill areas shall be within plus or minus 2/10 of one foot.
B. Street grading shall be within plus or minus 1/10 of one foot.
The civil engineer, or duly authorized representative, shall check all cut and fill areas to
observe that the work is in accordance with the above limits.
12. SUPERVISION AND CONSTRUCTION STAKING
Observation by the Soils Engineer shall be continuous during the placement of fill and
compaction operations so that he can declare that the fill was placed in general
conformance with specifications. All site visits necessary to test the placement of fill and
observe compaction operations will be at the expense of the Owner. All construction
staking will be provided by the Civil Engineer or his duly authorized representative.
Initial and final grading staking shall be at the expense of the owner. The replacement of
grade stakes through construction shall be at the expense of the contractor.
13. SEASONAL LIMITS
▪ • No fill material shall be placed, spread or rolled while it is frozen, thawing, or during
unfavorable weather conditions. When work is interrupted by heavy precipitation, fill
operations shall not be resumed until the Soils Engineer indicates that the moisture
content and dry density of previously placed materials are as specified.
14. NOTICE REGARDING START OF GRADING
The contractor shall submit notification to the Soils Engineer and Owner advising them
of the start of grading operations at least three (3) days in advance of the starting date.
Notification shall also be submitted at least 3 days in advance of any resumption dates
when grading operations have been stopped for any reason other than adverse weather
• conditions.
15. REPORTING OF FIELD DENSITY TESTS
Density tests made by the Soils Engineer, as specified under "Density Tests" above,
shall be submitted progressively to the Owner. Dry density, moisture content and
.
percent compaction shall be reported for each test taken.
16. DECLARATION REGARDING COMPLETED FILL
The Soils Engineer shall provide a written declaration stating that the site was filled with
• acceptable materials, or was placed in general accordance with the specifications.
•
CGRS,INC. C-3
CONQUEST OIL C7
• CTL IT PROJECT NO.FC03645.021-125
Hello