Telecommunications Reliability Facility - Fort Bragg - (1) Telecommunications Reliability Facility Geotechnical Final

SUBSURFACE EXPLORATION
AND
GEOTECHNICAL RECOMMENDATIONS REPORT

Telecommunications Reliability Facility, FY 17, PN 81894
Fort Bragg, North Carolina

By:

Chris Norton, P.E., Civil Engineer
Geotechnical and Dam Safety Section
U.S. Army Corps of Engineers, Wilmington District
December 2017
This report was prepared by the Wilmington District of the U.S. Army Corps of Engineers. The initials or
signatures and registration designation of individuals appear on these documents within the scope of
their employment as required by Engineer Regulation 1110-1-8152

Date: 21 December 2017

_______________________________
Christopher A. Norton, P.E.
Civil Engineer
CESAW-ECP-EG
Geotechnical and Dam Safety Section

_______________________________
Jason Inskeep, E.I.
Civil Engineer
CESAW-ECP-EG
Geotechnical and Dam Safety Section

NORTON.CHRIST
OPHER.ALLEN.14
58028903
Digitally signed by
NORTON.CHRISTOPHER.ALLEN.1458028903
DN: c=US, o=U.S. Government, ou=DoD,
ou=PKI, ou=USA,
cn=NORTON.CHRISTOPHER.ALLEN.1458028
903
Date: 2017.12.21 12:42:29 -05'00'
INSKEEP.JASON.ALEX
ANDER.1288384173
Digitally signed by
INSKEEP.JASON.ALEXANDER.1288384173
DN: c=US, o=U.S. Government, ou=DoD,
ou=PKI, ou=USA,
cn=INSKEEP.JASON.ALEXANDER.1288384173
Date: 2017.12.21 12:44:08 -05'00'
TABLE OF CONTENTS
1. PURPOSE .................................................................................................................................................. 1
2. QUALIFICATION OF REPORT ..................................................................................................................... 1
3. PROJECT DESCRIPTION ............................................................................................................................. 1
4. EXPLORATION PROCEDURES .................................................................................................................... 1
Site Reconnaissance ................................................................................................................................. 1
Soil Borings and DCP Testing ................................................................................................................... 2
Soil Infiltration Testing ............................................................................................................................. 2
5. SITE AND SUBSURFACE CONDITIONS ....................................................................................................... 3
Site Conditions ......................................................................................................................................... 3
Regional and Site Geology ....................................................................................................................... 3
Subsurface Conditions ............................................................................................................................. 4
Groundwater Conditions ......................................................................................................................... 4
6. ENGINEERING EVALUATIONS AND RECOMMENDATIONS ....................................................................... 5
General .................................................................................................................................................... 5
Geotechnical Investigations ..................................................................................................................... 5
Excavation, Grading, and Fill ................................................................................................................... 5
Damp-proofing and Water-proofing ....................................................................................................... 5
Presumptive Load-Bearing Values of Soils ............................................................................................... 5
Foundations ............................................................................................................................................. 6
Shallow Foundations ................................................................................................................................ 6
Frost Susceptibility ................................................................................................................................... 6
Seismic Site Classification ........................................................................................................................ 7
Liquefaction ............................................................................................................................................. 7

ATTACHMENT A: 35% Design Submittal – Site Plan
ATTACHMENT B: Boring, DCP, and Infiltration Testing Location Plan
ATTACHMENT C: Soil Test Boring Logs
ATTACHMENT D: CBR and UBC Tabulations
ATTACHMENT E: Infiltration Test Tabulations
ATTACHMENT F: Michigan Method – Soil Infiltration Testing
1. PURPOSE
The purpose of this “Subsurface Exploration and Geotechnical Recommendations Report” is to present
the findings and evaluation of subsurface data collected on 25 and 26 September, 2017, at the proposed
Telecommunications Reliability Facility site. This report provides a general overview of the site and
subsurface conditions encountered within the proposed footprint of the components in the 35 percent
design submittal, which was provided to the Wilmington District on 13 July, 2017 (Attachment A). The
proposed components consist of two infiltration basins and a one-story building. The building will be
founded on a shallow slab-on-grade concrete foundation. Preliminary engineering evaluations and
recommendations are also provided with respect to the geotechnical design and construction of the
project.
2. QUALIFICATION OF REPORT
The subsurface investigation was conducted to determine soil and groundwater conditions and was not
intended to serve as an assessment of site wetlands,environmental, or contaminant conditions. The
Architect-Engineer’s (A-E) team should include a Registered Professional Engineer, henceforth referred
to as Engineer, with an appropriate amount of experience in geotechnical engineering design. The
Engineer should be able to interpret this report, make a determination if a more extensive subsurface
investigation is required, and develop foundation and earthwork design parameters. Any additional
subsurface investigations and laboratory analyses conducted to better characterize the site and to
develop the final design should be performed under the direction of an Engineer with an appropriate
amount of experience in geotechnical engineering design.
3. PROJECT DESCRIPTION
The proposed 35 percent design site layout plan can be seen in Attachment A, and consists of a single
story concrete slab-on-grade building and two infiltration basins. The project is located within the
southwest corner of the Special Operations Training Facility (SOTF) compound, just west of the Antenna
Field. The proposed building location is an open grassy area between an existing barbed-wire fence to
the east and the existing wood-line to the west. A gravel parking lot will be constructed along the
southern side of the building, adjacent to the sidewalk. Two infiltration basins will be used for drainage,
one near the northwest corner of the proposed building, and one southeast of the proposed building on
the other side of the existing barbed-wire fence. A new security fence will be placed around the
proposed building connecting it to the rest of the SOTF compound. Please review Attachment A for
more details.
4. EXPLORATION PROCEDURES
Site Reconnaissance
Before the field investigation was performed, the proposed project site(s) and surrounding areas were
visually inspected. The observations were used in planning the subsurface exploration, in determining
areas of special interest, and in relating site conditions to known geologic conditions in the area.
1
Soil Borings and DCP Testing
Subsurface conditions within the proposed building footprint were evaluated by five soil test Hand
Auger (HA) borings labeled TEL-HA-17-01 through TEL-HA-17-05, and five companion Dynamic Cone
Penetrometer (DCP) tests labeled TEL-DCP-17-01 through TEL-DCP-17-05. The borings were taken to a
depth of approximately 7 feet Below Ground Surface (BGS), and the companion DCP tests were
conducted to approximately 6.5 feet BGS.
The HA borings and DCP testing were conducted to visually classify materials and to estimate
engineering properties of the material, respectively. The classifications and engineering properties may
be used in the evaluation and design of the proposed project. North Carolina State Plane Coordinates
(NAD83 - U.S. Survey Feet) and elevations (NAVD88) of borings/companion DCP tests are indicated in
Attachments B and C. State Plane Coordinates were established by a hand-held mapping grade GPS unit,
and should be considered approximate.
The HA borings were conducted in accordance with American Standard Test Method (ASTM) D1452,
with equipment consisting of 5-foot steel rod sections and a 3.25-inch outside diameter steel barrel
sampler. The DCP used for this investigation conforms to ASTM D6951, and consists of a 17.6-lb hammer
that is dropped (free fall) a distance of 22.6 inches, impacting an anvil attached to the drive rod. The
impact drives a 60° cone, attached to the end of the drive rod, into the material of interest. One impact
is equivalent to one “blow count”. The number of blow counts per inch of penetration is recorded
(number blow counts)/(inch of penetration). The blow counts are then used to calculate the California
Bearing Ratio (CBR) for each inch of strata. The CBR is a comparison of the penetration resistance of a
soil to the penetration into a standard crushed stone sample. Penetration resistance, when properly
evaluated, is an index of the soil’s strength, density, and foundation support capability. Equations used
to calculate the CBR are described in ASTM D6951. A correlation between the CBR and Ultimate Bearing
Capacity (UBC) has been developed by the U.S. Army Corps of Engineers (USACE). The derivation of the
correlation equation can be found in the research paper titled “Evaluation of In-Situ Pavement Layers
with the Dynamic Cone Penetrometer (DCP)”, Jeb S. Tingle, et al. The Engineer should note that the UBC
equation does not account for the Ground Water Table (GWT).
Soil classifications are shown on the soil test boring logs in Attachment C, and were determined in the
field by an Engineer. Soil samples were classified in accordance with ASTM D2488 (Visual-Manual
Procedure for Descriptions of Soils). The soil descriptions and classifications are based on visual
examination only; no lab analyses were conducted. CBR and UBC tabulations are included in Attachment
D of this report.
Soil Infiltration Testing
Soil infiltration tests were performed at two locations (TEL-INF-17-1 and TEL-INF-17-2). Boring logs for
these tests are located in Attachment C. These locations were selected based on the A-E’s proposed
location of the infiltration basins.
Testing was conducted using a modified version of the “Percolation Test”; the percolation test
procedure “Michigan Method” can be seen in Attachment F. A boring for each test was conducted by
hand auger to the approximate elevation of the basin invert. The invert elevation for both basins was
provided by the A-E, and required a 4 foot boring for TEL-INF-17-1 and a 5 foot boring for TEL-INF-17-2.
For general awareness, topographic contour lines and a typical drawing of the basins can be seen in
Attachment A. The testing varied from the procedure in Attachment F by utilization of a 3-inch diameter
2
PVC pipe that was inserted to the bottom of the bored hole and approximately 6 inches below the basin
invert. The primary purposes of the pipe was to prevent hole collapse and limit horizontal infiltration as
much as possible. After the PVC pipe was inserted, a 6 inch layer of pea gravel was placed at the bottom
of the pipe to increase soil stability. By inserting the pipe 6 inches below the basin invert, we made the
assumption that the rates recorded were vertical infiltration rates, i.e. the water level outside of the PVC
pipe remained at the bottom of the pipe, thus eliminating horizontal infiltration. In reality, this
assumption is not entirely correct since more than likely the actual outside water level was at some
point above the bottom of the pipe, thus some horizontal infiltration is inevitable. As a worst case
scenario, a scenario in which the water level inside the PVC pipe and the water level outside the pipe
came to equilibrium thus mimicking the actual percolation test, we applied the percolation test
reduction factor seen in Attachment F to the assumed vertical infiltration rates. In addition, it was
assumed that the soil at the invert of the basin was undisturbed, and therefore the measured infiltration
rates are those of the undisturbed soil. In reality, the soil structure was disturbed when the PVC pipe
was inserted 6 inches below the basin invert.
The tests were initiated by filling water to the top of pipe, then measuring from the top of pipe to the
water surface at fifteen (15) minute intervals for four hours, adding water as needed. The drop in water
surface over the timed interval was used to determine the rates in inches per hour.
The tip of the pipe was considered to be in the vadose zone and did not intercept the GWT for the tests.
The depth of the existing GWT was not identified during the site investigation and it is assumed that
there are no confining soil layers that restrict flow from the proposed infiltration basins to the GWT.
5. SITE AND SUBSURFACE CONDITIONS
Site Conditions
Significant grading and earthwork will be needed to construct the project. At the time of investigation,
the area of the new building was open and grassy and located between a chain-link barbed wire fence
along the western portion of the SOTF compound, and a dense stand of pine trees to the east of the
proposed building. The area had a moderate slope from the wood-line downhill to the fence. The
surface soils consisted of a loose Silty Sand (SM) with a high infiltration capacity.
The two proposed infiltration basins are located to the northwest and southeast of the proposed
building. The northwest basin is within the wood-line, and will require tree removal to construct. The
surface soils within the proposed area of this basin consist of loose SM with a high infiltration capacity.
The southeast basin is within the fenced part of the SOTF compound. The ground surface within the
proposed area of this basin consists of moderately compact SM with a high infiltration capacity.
No abnormal site conditions were noted.
Regional and Site Geology
Fort Bragg is situated in the “sand hills” area of the Coastal Plain physiographic province of North
Carolina. The Coastal Plain extends westward from the Atlantic Ocean to the Fall Line, a distance of
about 130 miles. The Fall Line is the boundary between the Coastal Plain and the Piedmont
physiographic provinces.
3
Geologic units in the area, ranging from oldest to youngest, include the Carolina Slate Belt rocks, which
are the basement rocks, the Cape Fear Formation, and the Middendorf Formation. The Cape Fear and
Middendorf Formations overlie the basement rock and are part of the generally southeastward-dipping
and thickening wedge of sediments that constitute the Atlantic Coastal Plain deposits. The Middendorf
Formation is exposed at land surface throughout the area. The formation is composed of tan, cross-
bedded, medium and fine-grained, micaceous quartz sand and clayey sand interbedded with clay or
sandy clay lenses or layers. Layers of hematite-cemented sandstone occur locally throughout the
Middendorf Formation as do thin layers of hard kaolin and kaolin-cemented sandstone. Below the water
table, these units are generally friable or plastic. In places, the Middendorf Formation is mottled orange,
gray, and tan color with streaks and laminae of red and purple hematite and manganese oxide stains.
Subsurface Conditions
Soil test borings TEL-HA-17-1 through TEL-HA-17-5 indicate a stratigraphy consisting of Poorly Graded
Sand (SP), Poorly Graded Sand with Silt (SP-SM), Poorly Graded Sand with Clay (SP-SC), and Clayey Sand
(SC). Lean Clay (CL), and Fat Clay (CH) were not encountered during this investigation. Soil test boring
logs are located in Attachment C.
DCP tests TEL-DCP-17-1 through TEL-DCP-17-5 indicate a range of CBRs and associated UBCs from 1.7
percent (762 psf) to 16.9 percent (3578 psf), as indicated in Attachment D, CBR and UBC Tabulations.
Lower strength material was encountered within the middle portion of all tests. DCP tests TEL-DCP-17-1
and TEL-DCP-17-2 indicate particularly low strength soils (less than 1000-psf) below a depth of 25
inches. Please refer to Attachment D for a detailed profile of CBR and UBC values for all tests.
Infiltration test data can be seen in Attachment E. Testing indicates a minimum infiltration rate of
approximately 1.49 inches per hour for TEL-INF-17-1 and 1.43 inches per hour for TEL-INF-17-2.
Attachment E can be reviewed for detailed infiltration testing data.
The above subsurface description is of a generalized nature to highlight the major subsurface
stratification features and material characteristics. The soil test boring logs should be reviewed for
specific information at individual boring locations. The stratifications shown on the soil test boring logs
represent the conditions at the actual boring locations only. Variations should be expected between
boring locations. The stratification lines shown on the soil test boring logs represent the approximate
boundaries between the subsurface materials; the actual transitions are typically more gradual.
Groundwater Conditions
Neither the apparent GWT nor the Seasonal High Water Table (SHWT) were located at any point during
this site investigation.
Due to the prevalence of SC and SP-SC at the project site and the general area, perched water conditions
could be encountered before, during, or after construction. A perched-water condition occurs when
water seeping downward is blocked by a low permeability soil layer, such as SC or CL, and saturates the
more permeable soil above it. The true GWT can be several to many feet below the perched-water level.
It should be noted that the GWT may vary during periods of prolonged drought and excessive rainfall, as
well as seasonally. Therefore, fluctuations in the GWT should be anticipated with changing climatic and
rainfall conditions.
4
6. ENGINEERING EVALUATIONS AND RECOMMENDATIONS
General
Chapters 16, 17, 18, and 33 of the International Building Code (IBC) 2012, adopted and modified by the
Unified Facilities Criteria (UFC) 3-220-01 of 2012, are the primary design standards referenced for these
recommendations. The following evaluations and recommendations are based on the information
available on the proposed structures, observations made at the project site, interpretation of the data
obtained from the soil test borings and associated DCP testing, and previous experience with soils and
subsurface conditions similar to those encountered at the site.
Geotechnical Investigations
A preliminary geotechnical investigation was conducted at the proposed project site by the Wilmington
District, and the results are discussed in this report. This investigation may not meet all requirements set
forth in Section 1803, IBC 2012, adopted and modified by Section 2-3.3, UFC 3-220-01, and this report
should be evaluated accordingly.
Excavation, Grading, and Fill
It is recommended that the Engineer adhere to the requirements set forth in Section 1804, IBC 2012,
adopted and modified by Section 2-3.4, UFC 3-220-01.
Where shallow foundations will bear on compacted fill material, the compacted fill should comply with
the criteria set forth in Section 1804.5, IBC 2012.
Where shallow foundations will bear on Controlled Low-Strength Material (CLSM), the CLSM should
comply with the criteria set forth in Section 1804.6, IBC 2012.
Damp-proofing and Water-proofing
It is recommended that the Engineer adhere to the requirements set forth in Section 1805, IBC 2012,
adopted and modified by Section 2-3.5, UFC 3-220-01. This may include additional investigation(s) to
verify the depth of the GWT or SHWT per Section 1803.5.4, IBC 2012, adopted and modified by Section
2-3.3.4 of UFC 3-220-01.
Presumptive Load-Bearing Values of Soils
It is recommended that the Engineer adhere to the requirements set forth in Section 1806, IBC 2012,
adopted and modified by Section 2-3.6, UFC 3-220-01.
As described above, soils with UBC’s less than 2000 psf were encountered at all locations and various
depths within the proposed building footprint. It is recommended that the Engineer review these
conditions and make a determination if improvement of subgrade materials is necessary, and if so, the
type of improvements needed and to what depth the improvements are needed.
The Engineer should evaluate this geotechnical investigation report, and determine if an additional
geotechnical investigation is required to confirm the load bearing values indicated in this report. The
Engineer should also use the Factors of Safety (FS) shown in Tables 2-2 and 2-3, UFC 3-220-01, when
5
developing the net allowable bearing capacities that will be used for design. All bearing capacities
provided in Attachment D are Ultimate Bearing Capacities (UBC), and should be reduced to Allowable
Bearing Capacities upon selection of the appropriate FS.
Foundations
It is recommended that foundations be designed and constructed in accordance with Sections 1808.2
through 1808.9, IBC 2012, adopted and modified by Section 2-3.8, UFC 3-220-01.
The foundation should be designed such that the net allowable bearing capacity of the soil is not
exceeded, and that total and differential settlement is limited to acceptable values. The net allowable
bearing capacity should be evaluated by the Engineer. Acceptable settlement values can be found in
Section 2-3.8.1, UFC 3-220-01.
The foundation should be designed for the most unfavorable effects due to the combinations of loads
specified in Chapter 16, IBC 2012. The Engineer should also consider possible future events such as
dewatering and flooding due to storms.
Expansive soils are not believed to exist at the site, however, the Engineer should make this
determination and adhere to Section 1808.6, IBC 2012, adopted and modified by Section 2-3.8.4, UFC 3-
220-01, should expansive soils be determined to exist at the site.
Shallow Foundations
It is recommended that shallow foundations be designed and constructed in accordance with Sections
1809.2 through 1809.13, IBC 2012, adopted and modified by Section 2-3.9, UFC 3-220-01.
Shallow foundations should be built on undisturbed soil, compacted fill material, or CLSM in accordance
with Section 1809.2, IBC 2012. Fill material and CLSM should meet the criteria discussed in “Excavation,
Grading, and Fill” of this report.
For excavations, it is recommended that the top 12 inches of finished subgrade be compacted to 95
percent of maximum dry density per ASTM D698.
For fill, it is recommended that material be placed in 6-inch lifts and compacted to 95 percent of
maximum dry density per ASTM D698. Fill material should not be placed over wet or frozen areas. Fill
material should be placed adjacent to structures, such as footings, after the structures have been
completed and accepted, and should be compacted as to avoid loading upon or against the structure.
Footings should be constructed at a minimum depth of 18 inches below the finished ground surface.
Spacing between footings should be at least 1.5 times the width of the larger foundation to minimize
any reduction in bearing capacity due to overlapping zones of influence. The minimum width of footings
should be 12 inches.
Frost Susceptibility
Frost susceptible soils are defined in American Society of Civil Engineers (ASCE) 32, and consist of soil
with greater than 6 percent by mass passing the #200 sieve in accordance with ASTM D422. Lab analyses
of collected samples were not conducted as part of this geotechnical investigation. Due to the suspected
clay content encountered in the soil test borings, it is recommended that the Engineer determine if frost
susceptible soils exist at the site, and if so, protect the foundation and other permanent supports by one
6
or more of the following methods indicated in Section 1809.5, IBC 2012, adopted and modified by
Section 2-3.9, UFC 3-220-01.
Seismic Site Classification
This geotechnical investigation is inadequate to provide the Seismic Site Classification (SSC) for the
proposed building site. It is recommended that the Engineer adhere to Section 1613.3.2, IBC 2012,
adopted and modified by Section 2-1.1.2, UFC 3-220-01, in order to verify the SSC. The SSC is designated
as A, B, C, D, E, or F in accordance with Chapter 20 of ASCE 7-10. The building official may provide an
assumed SSC, however, if one is not provided, and the soil properties are not known in sufficient detail
to verify the SSC, an SSC of D may be assumed for preliminary purposes. For design purposes, the
Engineer should verify the SSC by performing at least one boring to a depth of 100 feet or refusal
(defined as N>100 blows per foot), or other method as determined by the building official.
Liquefaction
This geotechnical investigation is inadequate to provide an assessment of liquefaction potential. It is
recommended that the Engineer adhere to Section 1613, IBC 2012, adopted and modified by Section 2-
1.1, UFC 3-220-01, regarding the assessment of liquefaction potential.
7
ATTACHMENT A
35% Design Submittal – Site Plan
Description DateRev.
RALEIGH, NC 27606-3394
[phone]
[phone] FAX
LICENSE # F-0672FOR OFFICIAL USE ONLYFOR OFFICIAL USE ONLYTELECOMMUNICATIONS
RELIABILITY FACILITY, SOTF
AS SHOWN35% SUBMITTALNOT FORCONSTRUCTION13 JULY 2017
PN-81894
U.S. ARMY CORPS OF ENGINEERS
69 DARLINGTON AVE
WILMINGTON DISTRICT
WILMINGTON, NORTH CAROLINA
ŠUS Army Corpsof EngineersEROSION AND SEDIMENT CONTROL PLANSCALE: 1"=10'CG101EROSION AND SEDIMENT
CONTROL PLAN010'10'30'1"=10'TPTPSFSFLODLODWWATTACHMENT A
ATTACHMENT A
ATTACHMENT B
Boring, DCP, and Infiltration Testing Location Plan
TEL-HA-17-5
TEL-HA-17-1
TEL-HA-17-4
TEL-HA-17-3
TEL-HA-17-2
TEL-INF-17-1
TEL-INF-17-2 !?
!?
!?
!?
!?
!?
!?
Telecommunications Reliability Facility
Ft. Bragg - PN 81894Data Source: CESAW, Stantec2013 Digital Orthphotography:OACSIM IGI&S Map Date: 10/23/2017
Ü
!?Hand Auger/Dynamic Cone Penetrometer Borings
!?Infilitration Test 0 25 5012.5 Feet
Overlay is based on the 35% plans and specs. Site layout was confirmed by Project Management on 17 August 2017. Coordinates are in North Carolina State Plane Feet (NAD83).
Bore_Label X YTEL-HA-17-2 1976375.201 510312.589TEL-HA-17-3 1976395.341 510266.341TEL-HA-17-4 1976350.661 510297.77TEL-HA-17-1 1976376.47 510254.971TEL-HA-17-5 1976373.629 510283.223TEL-INF-17-2 1976320.206 510300.049TEL-INF-17-1 1976473.464 510188.499
ATTACHMENT B
ATTACHMENT C
Soil Test Boring Logs
321.6
319.1
317.6
314.6
321.6
Chris Norton and Jason Inskeep
COMPLETED
Chris Norton, P.E., Civil Engineer
VERTICAL
18. SIGNATURE AND TITLE OF INSPECTOR
9. COORDINATE SYSTEM
SHEET
INCLINED
HORIZONTAL
3. DRILLING AGENCY
2. HOLE NUMBER
13. TOTAL NUMBER CORE BOXES
Fort Bragg, NC OF
Hand Auger
INSTALLATION
15. DATE BORING
17. TOTAL CORE RECOVERY FOR BORING
---
DISTURBED12. TOTAL SAMPLES
0
3
1. PROJECT
NAD83SOTF Telecommunications Reliability Facility
6. THICKNESS OF OVERBURDEN
7. DEPTH DRILLED INTO ROCK
8. TOTAL DEPTH OF BORING
STARTED
South Atlantic Division
USACE, Wilmington District
VERTICAL
UNDISTURBED
5. DIRECTION OF BORING
9/27/17
SHEETS
4. NAME OF DRILLER
BEARINGDEG FROM
VERTICAL
DIVISION
Date Drafted:10/1/2017
Reviewed By:Chris Norton, P.E.
Date Checked:10/19/2017
VERSION:Draft
TEL-HA-17-1
Drafted By:Jason Inskeep, E.I.T.
Boring was acquired with a Hand Auger
(HA).
3"
1
NAVD88
LOCATION COORDINATES
16. ELEVATION TOP OF BORING
14. ELEVATION GROUND WATER
DRILLING LOG
9/27/17
1
N 510254.13 E 1976376.47
0
11. MANUFACTURER'S DESIGNATION OF DRILL
10. SIZE AND TYPE OF BIT
7.0-ft
GWT not encountered
Boring Designation TEL-HA-17-1 SHEET 1 of 1
Boring Designation TEL-HA-17-1
OCT 2013
SAW FORM 1836-A (SOIL BORING)
REMARKS
(Drilling time, water loss, depth of
weathering, etc., if significant)
g
LEGEND
c
Wilmington District
Geotechnical and Dam Safety Section
SCALE
(feet)
b
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
ELEV
(feet)
a
Poorly Graded Sand with Silt (SP-SM), brown,
non-plastic, some rootlets
Poorly Graded Sand with Clay (SP-SC), orange to
brown, fine to medium grained
Poorly Graded Sand (SP), orange to brown and tan,
fine to medium grained
BOTTOM OF BOREHOLE AT 7.0 ft
SOILS ARE FIELD VISUALLY CLASSIFIED IN
ACCORDANCE WITH THE UNIFIED SOIL
CLASSIFICATION SYSTEM
FIELD CLASSIFICATION OF MATERIALS
(Description)
d
BOX OR
SAMPLE #
f
1-ft
3-ft
4.5-ft
0.5-ft
2.5-ft
4-ft
S-1
S-2
S-3
ATTACHMENT C
319.7
317.7
313.2
312.7
319.7
Chris Norton and Jason Inskeep
COMPLETED
Chris Norton, P.E., Civil Engineer
VERTICAL
18. SIGNATURE AND TITLE OF INSPECTOR
9. COORDINATE SYSTEM
SHEET
INCLINED
HORIZONTAL
3. DRILLING AGENCY
2. HOLE NUMBER
13. TOTAL NUMBER CORE BOXES
Fort Bragg, NC OF
Hand Auger
INSTALLATION
15. DATE BORING
17. TOTAL CORE RECOVERY FOR BORING
---
DISTURBED12. TOTAL SAMPLES
0
3
1. PROJECT
NAD83SOTF Telecommunications Reliability Facility
6. THICKNESS OF OVERBURDEN
7. DEPTH DRILLED INTO ROCK
8. TOTAL DEPTH OF BORING
STARTED
South Atlantic Division
USACE, Wilmington District
VERTICAL
UNDISTURBED
5. DIRECTION OF BORING
9/27/17
SHEETS
4. NAME OF DRILLER
BEARINGDEG FROM
VERTICAL
DIVISION
Date Drafted:10/1/2017
Reviewed By:Chris Norton, P.E.
Date Checked:10/19/2017
VERSION:Draft
TEL-HA-17-2
Drafted By:Jason Inskeep, E.I.T.
Boring was acquired with a Hand Auger
(HA).
3"
1
NAVD88
LOCATION COORDINATES
16. ELEVATION TOP OF BORING
14. ELEVATION GROUND WATER
DRILLING LOG
9/27/17
1
N 510312.589 E 1976375.201
0
11. MANUFACTURER'S DESIGNATION OF DRILL
10. SIZE AND TYPE OF BIT
7.0-ft
GWT not encountered
Boring Designation TEL-HA-17-2 SHEET 1 of 1
Boring Designation TEL-HA-17-2
OCT 2013
SAW FORM 1836-A (SOIL BORING)
REMARKS
(Drilling time, water loss, depth of
weathering, etc., if significant)
g
LEGEND
c
Wilmington District
Geotechnical and Dam Safety Section
SCALE
(feet)
b
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
ELEV
(feet)
a
Poorly Graded Sand with Silt (SP-SM), brown, fine to
medium grained, non-plastic, rootlets
Poorly Graded Sand with Clay (SP-SC), orange to
brown, fine to medium grained
Poorly Graded Sand with Clay (SP-SC), orange to
brown, fine to medium grained
BOTTOM OF BOREHOLE AT 7.0 ft
SOILS ARE FIELD VISUALLY CLASSIFIED IN
ACCORDANCE WITH THE UNIFIED SOIL
CLASSIFICATION SYSTEM
FIELD CLASSIFICATION OF MATERIALS
(Description)
d
BOX OR
SAMPLE #
f
1-ft
2.5-ft
7-ft
0.5-ft
2-ft
6.5-ft
S-1
S-2
S-3
ATTACHMENT C
319.9
319.4
314.9
313.4
312.4
319.9
Chris Norton and Jason Inskeep
COMPLETED
Chris Norton, P.E., Civil Engineer
VERTICAL
18. SIGNATURE AND TITLE OF INSPECTOR
9. COORDINATE SYSTEM
SHEET
INCLINED
HORIZONTAL
3. DRILLING AGENCY
2. HOLE NUMBER
13. TOTAL NUMBER CORE BOXES
Fort Bragg, NC OF
Hand Auger
INSTALLATION
15. DATE BORING
17. TOTAL CORE RECOVERY FOR BORING
---
DISTURBED12. TOTAL SAMPLES
0
4
1. PROJECT
NAD83SOTF Telecommunications Reliability Facility
6. THICKNESS OF OVERBURDEN
7. DEPTH DRILLED INTO ROCK
8. TOTAL DEPTH OF BORING
STARTED
South Atlantic Division
USACE, Wilmington District
VERTICAL
UNDISTURBED
5. DIRECTION OF BORING
9/27/17
SHEETS
4. NAME OF DRILLER
BEARINGDEG FROM
VERTICAL
DIVISION
Date Drafted:10/1/2017
Reviewed By:Chris Norton, P.E.
Date Checked:10/19/2017
VERSION:Draft
TEL-HA-17-3
Drafted By:Jason Inskeep, E.I.T.
Boring was acquired with a Hand Auger
(HA).
3"
1
NAVD88
LOCATION COORDINATES
16. ELEVATION TOP OF BORING
14. ELEVATION GROUND WATER
DRILLING LOG
9/27/17
1
N 510266.341 E 1976395.341
0
11. MANUFACTURER'S DESIGNATION OF DRILL
10. SIZE AND TYPE OF BIT
7.5-ft
GWT not encountered
Boring Designation TEL-HA-17-3 SHEET 1 of 1
Boring Designation TEL-HA-17-3
OCT 2013
SAW FORM 1836-A (SOIL BORING)
REMARKS
(Drilling time, water loss, depth of
weathering, etc., if significant)
g
LEGEND
c
Wilmington District
Geotechnical and Dam Safety Section
SCALE
(feet)
b
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
ELEV
(feet)
a
Poorly Graded Sand with Silt (SP-SM), brown, fine to
medium grained, non-plastic, rootlets
Poorly Graded Sand with Clay (SP-SC), orange to
brown, fine to medium grained
Poorly Graded Sand with Clay (SP-SC), orange to
brown, fine to medium grained
Poorly Graded Sand with Clay (SP-SC), orange to
brown, fine to medium grained
BOTTOM OF BOREHOLE AT 7.5 ft
SOILS ARE FIELD VISUALLY CLASSIFIED IN
ACCORDANCE WITH THE UNIFIED SOIL
CLASSIFICATION SYSTEM
FIELD CLASSIFICATION OF MATERIALS
(Description)
d
BOX OR
SAMPLE #
f
1-ft
2.5-ft
5.5-ft
7.5-ft
0.5-ft
2-ft
5-ft
7-ft
S-1
S-2
S-3
S-4
ATTACHMENT C
321.5
319.5
317.0
315.0
314.5
321.5
Chris Norton and Jason Inskeep
COMPLETED
Chris Norton, P.E., Civil Engineer
VERTICAL
18. SIGNATURE AND TITLE OF INSPECTOR
9. COORDINATE SYSTEM
SHEET
INCLINED
HORIZONTAL
3. DRILLING AGENCY
2. HOLE NUMBER
13. TOTAL NUMBER CORE BOXES
Fort Bragg, NC OF
Hand Auger
INSTALLATION
15. DATE BORING
17. TOTAL CORE RECOVERY FOR BORING
---
DISTURBED12. TOTAL SAMPLES
0
4
1. PROJECT
NAD83SOTF Telecommunications Reliability Facility
6. THICKNESS OF OVERBURDEN
7. DEPTH DRILLED INTO ROCK
8. TOTAL DEPTH OF BORING
STARTED
South Atlantic Division
USACE, Wilmington District
VERTICAL
UNDISTURBED
5. DIRECTION OF BORING
9/27/17
SHEETS
4. NAME OF DRILLER
BEARINGDEG FROM
VERTICAL
DIVISION
Date Drafted:10/1/2017
Reviewed By:Chris Norton, P.E.
Date Checked:10/19/2017
VERSION:Draft
TEL-HA-17-4
Drafted By:Jason Inskeep, E.I.T.
Boring was acquired with a Hand Auger
(HA).
3"
1
NAVD88
LOCATION COORDINATES
16. ELEVATION TOP OF BORING
14. ELEVATION GROUND WATER
DRILLING LOG
9/27/17
1
N 510297.77 E 1976350.661
0
11. MANUFACTURER'S DESIGNATION OF DRILL
10. SIZE AND TYPE OF BIT
7.0-ft
GWT not encountered
Boring Designation TEL-HA-17-4 SHEET 1 of 1
Boring Designation TEL-HA-17-4
OCT 2013
SAW FORM 1836-A (SOIL BORING)
REMARKS
(Drilling time, water loss, depth of
weathering, etc., if significant)
g
LEGEND
c
Wilmington District
Geotechnical and Dam Safety Section
SCALE
(feet)
b
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
ELEV
(feet)
a
Poorly Graded Sand with Silt (SP-SM), brown, fine to
medium grained, non-plastic, rootlets
Poorly Graded Sand with Clay (SP-SC), brown, fine to
medium grained
Poorly Graded Sand with Clay (SP-SC), brown, fine to
medium grained
Poorly Graded Sand (SP), orange to brown, fine
grained
BOTTOM OF BOREHOLE AT 7.0 ft
SOILS ARE FIELD VISUALLY CLASSIFIED IN
ACCORDANCE WITH THE UNIFIED SOIL
CLASSIFICATION SYSTEM
FIELD CLASSIFICATION OF MATERIALS
(Description)
d
BOX OR
SAMPLE #
f
1-ft
2.5-ft
5-ft
7-ft
0.5-ft
2-ft
4.5-ft
6.5-ft
S-1
S-2
S-3
S-4
ATTACHMENT C
320.8
318.8
316.8
315.8
313.8
320.8
Chris Norton and Jason Inskeep
COMPLETED
Chris Norton, P.E., Civil Engineer
VERTICAL
18. SIGNATURE AND TITLE OF INSPECTOR
9. COORDINATE SYSTEM
SHEET
INCLINED
HORIZONTAL
3. DRILLING AGENCY
2. HOLE NUMBER
13. TOTAL NUMBER CORE BOXES
Fort Bragg, NC OF
Hand Auger
INSTALLATION
15. DATE BORING
17. TOTAL CORE RECOVERY FOR BORING
---
DISTURBED12. TOTAL SAMPLES
0
4
1. PROJECT
NAD83SOTF Telecommunications Reliability Facility
6. THICKNESS OF OVERBURDEN
7. DEPTH DRILLED INTO ROCK
8. TOTAL DEPTH OF BORING
STARTED
South Atlantic Division
USACE, Wilmington District
VERTICAL
UNDISTURBED
5. DIRECTION OF BORING
9/27/17
SHEETS
4. NAME OF DRILLER
BEARINGDEG FROM
VERTICAL
DIVISION
Date Drafted:10/1/2017
Reviewed By:Chris Norton, P.E.
Date Checked:10/19/2017
VERSION:Draft
TEL-HA-17-5
Drafted By:Jason Inskeep, E.I.T.
Boring was acquired with a Hand Auger
(HA).
Elevation Top of Boring estimated
using existing topographic survey
contours. Please see Attachment B.
3"
1
NAVD88
LOCATION COORDINATES
16. ELEVATION TOP OF BORING
14. ELEVATION GROUND WATER
DRILLING LOG
9/27/17
1
N 510283.22 E 1976373.63
0
11. MANUFACTURER'S DESIGNATION OF DRILL
10. SIZE AND TYPE OF BIT
7.0-ft
GWT not encountered
Boring Designation TEL-HA-17-5 SHEET 1 of 1
Boring Designation TEL-HA-17-5
OCT 2013
SAW FORM 1836-A (SOIL BORING)
REMARKS
(Drilling time, water loss, depth of
weathering, etc., if significant)
g
LEGEND
c
Wilmington District
Geotechnical and Dam Safety Section
SCALE
(feet)
b
0.0
1.0
2.0
3.0
4.0
5.0
6.0
7.0
ELEV
(feet)
a
Poorly Graded Sand with Silt (SP-SM), brown, fine to
medium grained, non-plastic, little organics
Clayey Sand (SC), orange to brown, fine grained
Poorly Graded Sand with Clay (SP-SC), orange to
brown, fine grained
Poorly Graded Sand (SP), orange to brown, fine
grained
BOTTOM OF BOREHOLE AT 7.0 ft
SOILS ARE FIELD VISUALLY CLASSIFIED IN
ACCORDANCE WITH THE UNIFIED SOIL
CLASSIFICATION SYSTEM
FIELD CLASSIFICATION OF MATERIALS
(Description)
d
BOX OR
SAMPLE #
f
1-ft
2.5-ft
4.5-ft
5.5-ft
0.5-ft
2-ft
4-ft
5-ft
S-1
S-2
S-3
S-4
ATTACHMENT C
317.4
315.4
314.4
313.4
317.4
Chris Norton and Jason Inskeep
COMPLETED
Chris Norton, P.E., Civil Engineer
VERTICAL
18. SIGNATURE AND TITLE OF INSPECTOR
9. COORDINATE SYSTEM
SHEET
INCLINED
HORIZONTAL
3. DRILLING AGENCY
2. HOLE NUMBER
13. TOTAL NUMBER CORE BOXES
Fort Bragg, NC OF
Hand Auger
INSTALLATION
15. DATE BORING
17. TOTAL CORE RECOVERY FOR BORING
---
DISTURBED12. TOTAL SAMPLES
0
0
1. PROJECT
NAD83SOTF Telecommunications Reliability Facility
6. THICKNESS OF OVERBURDEN
7. DEPTH DRILLED INTO ROCK
8. TOTAL DEPTH OF BORING
STARTED
South Atlantic Division
USACE, Wilmington District
VERTICAL
UNDISTURBED
5. DIRECTION OF BORING
9/28/17
SHEETS
4. NAME OF DRILLER
BEARINGDEG FROM
VERTICAL
DIVISION
Date Drafted:10/1/2017
Reviewed By:Chris Norton, P.E.
Date Checked:10/19/2017
VERSION:Draft
TEL-INF-17-1
Drafted By:Jason Inskeep, E.I.T.
Boring was acquired with a Hand Auger
(HA).
Elevation Top of Boring estimated
using existing topographic survey
contours. Please see Attachment B.
3"
1
NAVD88
LOCATION COORDINATES
16. ELEVATION TOP OF BORING
14. ELEVATION GROUND WATER
DRILLING LOG
9/28/17
1
N 510188.5 E 1976473.46
0
11. MANUFACTURER'S DESIGNATION OF DRILL
10. SIZE AND TYPE OF BIT
4.0-ft
GWT not encountered
Boring Designation TEL-INF-17-1 SHEET 1 of 1
Boring Designation TEL-INF-17-1
OCT 2013
SAW FORM 1836-A (SOIL BORING)
REMARKS
(Drilling time, water loss, depth of
weathering, etc., if significant)
g
LEGEND
c
Wilmington District
Geotechnical and Dam Safety Section
SCALE
(feet)
b
0.0
1.0
2.0
3.0
4.0
ELEV
(feet)
a
Poorly Graded Sand with Silt (SP-SM), brown, fine to
medium grained, non-plastic, some small rock
Clayey Sand (SC), orange to brown, fine to medium
grained
Poorly Graded Sand with Clay (SP-SC), fine to
medium grained
BOTTOM OF BOREHOLE AT 4.0 ft
SOILS ARE FIELD VISUALLY CLASSIFIED IN
ACCORDANCE WITH THE UNIFIED SOIL
CLASSIFICATION SYSTEM
FIELD CLASSIFICATION OF MATERIALS
(Description)
d
BOX OR
SAMPLE #
f
ATTACHMENT C
321.6
320.6
318.1
316.6
321.6
Chris Norton and Jason Inskeep
COMPLETED
Chris Norton, P.E., Civil Engineer
VERTICAL
18. SIGNATURE AND TITLE OF INSPECTOR
9. COORDINATE SYSTEM
SHEET
INCLINED
HORIZONTAL
3. DRILLING AGENCY
2. HOLE NUMBER
13. TOTAL NUMBER CORE BOXES
Fort Bragg, NC OF
Hand Auger
INSTALLATION
15. DATE BORING
17. TOTAL CORE RECOVERY FOR BORING
---
DISTURBED12. TOTAL SAMPLES
0
0
1. PROJECT
NAD83SOTF Telecommunications Reliability Facility
6. THICKNESS OF OVERBURDEN
7. DEPTH DRILLED INTO ROCK
8. TOTAL DEPTH OF BORING
STARTED
South Atlantic Division
USACE, Wilmington District
VERTICAL
UNDISTURBED
5. DIRECTION OF BORING
9/28/17
SHEETS
4. NAME OF DRILLER
BEARINGDEG FROM
VERTICAL
DIVISION
Date Drafted:10/1/2017
Reviewed By:Chris Norton, P.E.
Date Checked:10/19/2017
VERSION:Draft
TEL-INF-17-2
Drafted By:Jason Inskeep, E.I.T.
Boring was acquired with a Hand Auger
(HA).
Elevation Top of Boring estimated
using existing topographic survey
contours. Please see Attachment B.
3"
1
NAVD88
LOCATION COORDINATES
16. ELEVATION TOP OF BORING
14. ELEVATION GROUND WATER
DRILLING LOG
9/28/17
1
N 510300.05 E 1976320.21
0
11. MANUFACTURER'S DESIGNATION OF DRILL
10. SIZE AND TYPE OF BIT
5.0-ft
GWT not encountered
Boring Designation TEL-INF-17-2 SHEET 1 of 1
Boring Designation TEL-INF-17-2
OCT 2013
SAW FORM 1836-A (SOIL BORING)
REMARKS
(Drilling time, water loss, depth of
weathering, etc., if significant)
g
LEGEND
c
Wilmington District
Geotechnical and Dam Safety Section
SCALE
(feet)
b
0.0
1.0
2.0
3.0
4.0
5.0
ELEV
(feet)
a
Poorly Graded Sand with Silt (SP-SM), brown to tan,
fine to medium grained
Poorly Graded Sand with Clay (SP-SC), brown to
orange, fine to medium grained
Poorly Graded Sand (SP), brown to orange, fine to
medium grained
BOTTOM OF BOREHOLE AT 5.0 ft
SOILS ARE FIELD VISUALLY CLASSIFIED IN
ACCORDANCE WITH THE UNIFIED SOIL
CLASSIFICATION SYSTEM
FIELD CLASSIFICATION OF MATERIALS
(Description)
d
BOX OR
SAMPLE #
f
ATTACHMENT C
ATTACHMENT D
CBR and UBC Tabulations
Boring ID:Boring ID:Boring ID:
TOH Elev.TOH Elev.TOH Elev.
Northing Northing Northing
Easting Easting Easting
NAVD 88 CBR Ultimate NAVD 88 CBR Ultimate NAVD 88 CBR Ultimate
Elevation Bearing Elevation Bearing Elevation Bearing
Depth Depth Capacity Capacity Capacity
(in)(ft)(ft)(%)(psf)(ft)(%)(psf)(ft)(%)(psf)
1 0.08 321.52 7.8 2137 319.62 5.6 1725 319.82 5.6 1725
2 0.17 321.43 7.8 2137 319.53 5.6 1725 319.73 5.6 1725
3 0.25 321.35 7.8 2137 319.45 7.8 2137 319.65 7.8 2137
4 0.33 321.27 16.9 3578 319.37 7.8 2137 319.57 7.8 2137
5 0.42 321.18 12.3 2889 319.28 7.8 2137 319.48 7.8 2137
6 0.50 321.10 12.3 2889 319.20 7.8 2137 319.40 7.8 2137
7 0.58 321.02 7.8 2137 319.12 7.8 2137 319.32 7.8 2137
8 0.67 320.93 7.8 2137 319.03 7.8 2137 319.23 7.8 2137
9 0.75 320.85 16.9 3578 318.95 7.8 2137 319.15 16.9 3578
10 0.83 320.77 7.8 2137 318.87 7.8 2137 319.07 7.8 2137
11 0.92 320.68 7.8 2137 318.78 7.8 2137 318.98 7.8 2137
12 1.00 320.60 7.8 2137 318.70 7.8 2137 318.90 7.8 2137
13 1.08 320.52 7.8 2137 318.62 10.0 2522 318.82 7.8 2137
14 1.17 320.43 7.8 2137 318.53 7.8 2137 318.73 7.8 2137
15 1.25 320.35 7.8 2137 318.45 7.8 2137 318.65 7.8 2137
16 1.33 320.27 7.8 2137 318.37 7.8 2137 318.57 7.8 2137
17 1.42 320.18 7.8 2137 318.28 7.8 2137 318.48 7.8 2137
18 1.50 320.10 7.8 2137 318.20 7.8 2137 318.40 7.8 2137
19 1.58 320.02 7.8 2137 318.12 5.6 1725 318.32 7.8 2137
20 1.67 319.93 7.8 2137 318.03 5.6 1725 318.23 7.8 2137
21 1.75 319.85 7.8 2137 317.95 5.6 1725 318.15 7.8 2137
22 1.83 319.77 7.8 2137 317.87 5.6 1725 318.07 7.8 2137
23 1.92 319.68 7.8 2137 317.78 5.6 1725 317.98 5.6 1725
24 2.00 319.60 3.6 1276 317.70 5.6 1725 317.90 5.6 1725
25 2.08 319.52 3.6 1276 317.62 5.6 1725 317.82 5.6 1725
26 2.17 319.43 317.53 3.6 1276 317.73 5.6 1725
27 2.25 319.35 317.45 3.6 1276 317.65 5.6 1725
28 2.33 319.27 317.37 2.3 937 317.57 5.6 1725
29 2.42 319.18 317.28 2.3 937 317.48
30 2.50 319.10 317.20 2.3 937 317.40
31 2.58 319.02 317.12 2.3 937 317.32 3.6 1276
32 2.67 318.93 1.7 762 317.03 2.3 937 317.23 3.6 1276
33 2.75 318.85 1.7 762 316.95 2.3 937 317.15 3.6 1276
34 2.83 318.77 1.7 762 316.87 2.3 937 317.07 3.6 1276
Notes: Top of Hole (TOH) depth is 0; Horizontal Datum is NC State Plane (US Survey Feet); Vertical Datum is
NAVD88; DCP conforms to ASTM D6951; CBR per ASTM D6951; Ultimate Bearing Capacity correlation per
"Evaluation of In Situ Pavemement Layers with the Dynamic Cone Penetrometer (DCP)", Jeb S. Tingle, et. al.
510254.97
1976376.47
510266.34
1976395.34
510312.59
1976375.20
321.6 319.7 319.9
TEL-DCP-17-2 TEL-DCP-17-3TEL-DCP-17-1
ATTACHMENT D
Boring ID:Boring ID:Boring ID:
TOH Elev.TOH Elev.TOH Elev.
Northing Northing Northing
Easting Easting Easting
NAVD 88 CBR Ultimate NAVD 88 CBR Ultimate NAVD 88 CBR Ultimate
Elevation Bearing Elevation Bearing Elevation Bearing
Depth Depth Capacity Capacity Capacity
(in)(ft)(ft)(%)(psf)(ft)(%)(psf)(ft)(%)(psf)
35 2.92 318.68 3.6 1276 316.78 2.3 937 316.98 3.6 1276
36 3.00 318.60 3.6 1276 316.70 2.3 937 316.90 3.6 1276
37 3.08 318.52 5.6 1725 316.62 3.6 1276 316.82 3.6 1276
38 3.17 318.43 5.6 1725 316.53 3.6 1276 316.73 3.6 1276
39 3.25 318.35 3.6 1276 316.45 2.3 937 316.65 3.6 1276
40 3.33 318.27 3.6 1276 316.37 2.3 937 316.57 3.6 1276
41 3.42 318.18 3.6 1276 316.28 2.3 937 316.48 3.6 1276
42 3.50 318.10 3.6 1276 316.20 2.3 937 316.40 3.6 1276
43 3.58 318.02 3.6 1276 316.12 2.3 937 316.32 3.6 1276
44 3.67 317.93 3.6 1276 316.03 2.3 937 316.23 3.6 1276
45 3.75 317.85 3.6 1276 315.95 3.6 1276 316.15 3.6 1276
46 3.83 317.77 3.6 1276 315.87 3.6 1276 316.07 3.6 1276
47 3.92 317.68 3.6 1276 315.78 2.3 937 315.98 3.6 1276
48 4.00 317.60 3.6 1276 315.70 2.3 937 315.90 3.6 1276
49 4.08 317.52 3.6 1276 315.62 2.3 937 315.82 5.6 1725
50 4.17 317.43 3.6 1276 315.53 2.3 937 315.73 5.6 1725
51 4.25 317.35 3.6 1276 315.45 2.3 937 315.65 5.6 1725
52 4.33 317.27 3.6 1276 315.37 2.3 937 315.57 5.6 1725
53 4.42 317.18 3.6 1276 315.28 3.6 1276 315.48 5.6 1725
54 4.50 317.10 3.6 1276 315.20 3.6 1276 315.40 5.6 1725
55 4.58 317.02 3.6 1276 315.12 3.6 1276 315.32 5.6 1725
56 4.67 316.93 3.6 1276 315.03 3.6 1276 315.23 5.6 1725
57 4.75 316.85 3.6 1276 314.95 3.6 1276 315.15 5.6 1725
58 4.83 316.77 5.6 1725 314.87 3.6 1276 315.07 5.6 1725
59 4.92 316.68 5.6 1725 314.78 3.6 1276 314.98 7.8 2137
60 5.00 316.60 3.6 1276 314.70 3.6 1276 314.90 7.8 2137
61 5.08 316.52 3.6 1276 314.62 3.6 1276 314.82 5.6 1725
62 5.17 316.43 3.6 1276 314.53 3.6 1276 314.73 5.6 1725
63 5.25 316.35 3.6 1276 314.45 5.6 1725 314.65 5.6 1725
64 5.33 316.27 5.6 1725 314.37 5.6 1725 314.57 5.6 1725
65 5.42 316.18 5.6 1725 314.28 5.6 1725 314.48 7.8 2137
66 5.50 316.10 5.6 1725 314.20 5.6 1725 314.40 7.8 2137
67 5.58 316.02 5.6 1725 314.12 5.6 1725 314.32 7.8 2137
68 5.67 315.93 5.6 1725 314.03 5.6 1725 314.23 7.8 2137
321.6 319.7 319.9
510254.97 510312.59 510266.34
1976376.47 1976375.20 1976395.34
Notes: Top of Hole (TOH) depth is 0; Horizontal Datum is NC State Plane (US Survey Feet); Vertical Datum is
NAVD88; DCP conforms to ASTM D6951; CBR per ASTM D6951; Ultimate Bearing Capacity correlation per
"Evaluation of In Situ Pavemement Layers with the Dynamic Cone Penetrometer (DCP)", Jeb S. Tingle, et. al.
TEL-DCP-17-1 TEL-DCP-17-2 TEL-DCP-17-3
ATTACHMENT D
Boring ID:Boring ID:Boring ID:
TOH Elev.TOH Elev.TOH Elev.
Northing Northing Northing
Easting Easting Easting
NAVD 88 CBR Ultimate NAVD 88 CBR Ultimate NAVD 88 CBR Ultimate
Elevation Bearing Elevation Bearing Elevation Bearing
Depth Depth Capacity Capacity Capacity
(in)(ft)(ft)(%)(psf)(ft)(%)(psf)(ft)(%)(psf)
69 5.75 315.85 5.6 1725 313.95 3.6 1276 314.15 7.8 2137
70 5.83 315.77 5.6 1725 313.87 3.6 1276 314.07 7.8 2137
71 5.92 315.68 5.6 1725 313.78 5.6 1725 313.98 7.8 2137
72 6.00 315.60 7.8 2137 313.70 5.6 1725 313.90 7.8 2137
73 6.08 315.52 7.8 2137 313.62 5.6 1725 313.82 7.8 2137
74 6.17 315.43 7.8 2137 313.53 5.6 1725 313.73 7.8 2137
75 6.25 315.35 7.8 2137 313.45 5.6 1725 313.65 5.6 1725
76 6.33 315.27 313.37 5.6 1725 313.57 5.6 1725
77 6.42 315.18 313.28 5.6 1725 313.48 5.6 1725
321.6 319.7 319.9
510254.97 510312.59 510266.34
1976376.47 1976375.20 1976395.34
Notes: Top of Hole (TOH) depth is 0; Horizontal Datum is NC State Plane (US Survey Feet); Vertical Datum is
NAVD88; DCP conforms to ASTM D6951; CBR per ASTM D6951; Ultimate Bearing Capacity correlation per
"Evaluation of In Situ Pavemement Layers with the Dynamic Cone Penetrometer (DCP)", Jeb S. Tingle, et. al.
TEL-DCP-17-1 TEL-DCP-17-2 TEL-DCP-17-3
ATTACHMENT D
Boring ID:Boring ID:
TOH Elev.TOH Elev.
Northing Northing
Easting Easting
NAVD 88 CBR Ultimate NAVD 88 CBR Ultimate
Elevation Bearing Elevation Bearing
Depth Depth Capacity Capacity
(in)(ft)(ft)(%)(psf)(ft)(%)(psf)
1 0.08 321.42 3.6 1276 320.72 3.6 1276
2 0.17 321.33 3.6 1276 320.63 3.6 1276
3 0.25 321.25 5.6 1725 320.55 7.8 2137
4 0.33 321.17 5.6 1725 320.47 7.8 2137
5 0.42 321.08 7.8 2137 320.38 10.0 2522
6 0.50 321.00 7.8 2137 320.30 16.9 3578
7 0.58 320.92 7.8 2137 320.22 16.9 3578
8 0.67 320.83 7.8 2137 320.13 7.8 2137
9 0.75 320.75 16.9 3578 320.05 16.9 3578
10 0.83 320.67 7.8 2137 319.97 16.9 3578
11 0.92 320.58 7.8 2137 319.88 7.8 2137
12 1.00 320.50 7.8 2137 319.80 16.9 3578
13 1.08 320.42 7.8 2137 319.72 7.8 2137
14 1.17 320.33 7.8 2137 319.63 7.8 2137
15 1.25 320.25 7.8 2137 319.55 16.9 3578
16 1.33 320.17 7.8 2137 319.47 7.8 2137
17 1.42 320.08 7.8 2137 319.38 7.8 2137
18 1.50 320.00 7.8 2137 319.30 7.8 2137
19 1.58 319.92 7.8 2137 319.22 7.8 2137
20 1.67 319.83 5.6 1725 319.13 7.8 2137
21 1.75 319.75 5.6 1725 319.05 7.8 2137
22 1.83 319.67 5.6 1725 318.97 5.6 1725
23 1.92 319.58 5.6 1725 318.88 3.6 1276
24 2.00 319.50 5.6 1725 318.80 3.6 1276
25 2.08 319.42 5.6 1725 318.72 3.6 1276
26 2.17 319.33 5.6 1725 318.63 3.6 1276
27 2.25 319.25 5.6 1725 318.55 5.6 1725
28 2.33 319.17 5.6 1725 318.47 5.6 1725
29 2.42 319.08 5.6 1725 318.38 5.6 1725
30 2.50 319.00 5.6 1725 318.30 5.6 1725
31 2.58 318.92 3.6 1276 318.22 3.6 1276
32 2.67 318.83 3.6 1276 318.13 3.6 1276
33 2.75 318.75 3.6 1276 318.05 3.6 1276
34 2.83 318.67 3.6 1276 317.97 3.6 1276
321.5 320.8
Notes: Top of Hole (TOH) depth is 0; Horizontal Datum is NC State Plane (US Survey Feet); Vertical Datum is
NAVD88; DCP conforms to ASTM D6951; CBR per ASTM D6951; Ultimate Bearing Capacity correlation per
"Evaluation of In Situ Pavemement Layers with the Dynamic Cone Penetrometer (DCP)", Jeb S. Tingle, et. al.
510283.22
1976373.63
510297.77
1976350.66
TEL-DCP-17-4 TEL-DCP-17-5
ATTACHMENT D
Boring ID:Boring ID:
TOH Elev.TOH Elev.
Northing Northing
Easting Easting
NAVD 88 CBR Ultimate NAVD 88 CBR Ultimate
Elevation Bearing Elevation Bearing
Depth Depth Capacity Capacity
(in)(ft)(ft)(%)(psf)(ft)(%)(psf)
35 2.92 318.58 3.6 1276 317.88 3.6 1276
36 3.00 318.50 3.6 1276 317.80 3.6 1276
37 3.08 318.42 3.6 1276 317.72 3.6 1276
38 3.17 318.33 3.6 1276 317.63 3.6 1276
39 3.25 318.25 3.6 1276 317.55 3.6 1276
40 3.33 318.17 3.6 1276 317.47 3.6 1276
41 3.42 318.08 3.6 1276 317.38 3.6 1276
42 3.50 318.00 3.6 1276 317.30 3.6 1276
43 3.58 317.92 3.6 1276 317.22 3.6 1276
44 3.67 317.83 3.6 1276 317.13 3.6 1276
45 3.75 317.75 3.6 1276 317.05 3.6 1276
46 3.83 317.67 3.6 1276 316.97 3.6 1276
47 3.92 317.58 3.6 1276 316.88 3.6 1276
48 4.00 317.50 3.6 1276 316.80 3.6 1276
49 4.08 317.42 3.6 1276 316.72 3.6 1276
50 4.17 317.33 3.6 1276 316.63 3.6 1276
51 4.25 317.25 3.6 1276 316.55 3.6 1276
52 4.33 317.17 3.6 1276 316.47 3.6 1276
53 4.42 317.08 3.6 1276 316.38 5.6 1725
54 4.50 317.00 3.6 1276 316.30 5.6 1725
55 4.58 316.92 3.6 1276 316.22 5.6 1725
56 4.67 316.83 3.6 1276 316.13 5.6 1725
57 4.75 316.75 5.6 1725 316.05 3.6 1276
58 4.83 316.67 3.6 1276 315.97 3.6 1276
59 4.92 316.58 3.6 1276 315.88 5.6 1725
60 5.00 316.50 7.8 2137 315.80 5.6 1725
61 5.08 316.42 5.6 1725 315.72 3.6 1276
62 5.17 316.33 5.6 1725 315.63 3.6 1276
63 5.25 316.25 5.6 1725 315.55 5.6 1725
64 5.33 316.17 5.6 1725 315.47 5.6 1725
65 5.42 316.08 7.8 2137 315.38 5.6 1725
66 5.50 316.00 5.6 1725 315.30 5.6 1725
67 5.58 315.92 5.6 1725 315.22 5.6 1725
68 5.67 315.83 5.6 1725 315.13 5.6 1725
TEL-DCP-17-4 TEL-DCP-17-5
321.5 320.8
510297.77 510283.22
1976350.66 1976373.63
Notes: Top of Hole (TOH) depth is 0; Horizontal Datum is NC State Plane (US Survey Feet); Vertical Datum is
NAVD88; DCP conforms to ASTM D6951; CBR per ASTM D6951; Ultimate Bearing Capacity correlation per
"Evaluation of In Situ Pavemement Layers with the Dynamic Cone Penetrometer (DCP)", Jeb S. Tingle, et. al.
ATTACHMENT D
Boring ID:Boring ID:
TOH Elev.TOH Elev.
Northing Northing
Easting Easting
NAVD 88 CBR Ultimate NAVD 88 CBR Ultimate
Elevation Bearing Elevation Bearing
Depth Depth Capacity Capacity
(in)(ft)(ft)(%)(psf)(ft)(%)(psf)
69 5.75 315.75 5.6 1725 315.05 5.6 1725
70 5.83 315.67 5.6 1725 314.97 5.6 1725
71 5.92 315.58 5.6 1725 314.88 5.6 1725
72 6.00 315.50 5.6 1725 314.80 5.6 1725
73 6.08 315.42 5.6 1725 314.72 7.8 2137
74 6.17 315.33 7.8 2137 314.63 7.8 2137
75 6.25 315.25 7.8 2137 314.55 5.6 1725
76 6.33 315.17 7.8 2137 314.47 5.6 1725
77 6.42 315.08 7.8 2137 314.38 5.6 1725
TEL-DCP-17-4 TEL-DCP-17-5
Notes: Top of Hole (TOH) depth is 0; Horizontal Datum is NC State Plane (US Survey Feet); Vertical Datum is
NAVD88; DCP conforms to ASTM D6951; CBR per ASTM D6951; Ultimate Bearing Capacity correlation per
"Evaluation of In Situ Pavemement Layers with the Dynamic Cone Penetrometer (DCP)", Jeb S. Tingle, et. al.
321.5 320.8
510297.77 510283.22
1976350.66 1976373.63
ATTACHMENT D
ATTACHMENT E
Infiltration Test Tabulations
(in)(in)(in)(in/hr)(in/hr)
TEL-INF-17-1 9:00 9:15 15 48.00 35.00 13.00 52.00 1.81
9:15 9:30 15 35.00 23.50 11.50 46.00 2.24
9:30 9:45 15 48.00 34.00 14.00 56.00 1.98
1976473.46 N 9:45 10:00 15 34.00 22.50 11.50 46.00 2.32
510188.5 W 10:00 10:15 15 34.50 23.50 11.00 44.00 2.16
10:15 10:30 15 23.50 15.50 8.00 32.00 2.29
10:30 10:45 15 24.50 16.50 8.00 32.00 2.18
10:45 11:00 15 31.25 22.50 8.75 35.00 1.85
11:00 11:15 15 22.50 16.00 6.50 26.00 1.88
11:15 11:30 15 30.50 23.25 7.25 29.00 1.53
11:30 11:45 15 23.25 16.50 6.75 27.00 1.89
11:45 12:00 15 32.50 25.00 7.50 30.00 1.49
12:00 12:15 15 25.00 17.50 7.50 30.00 1.98
12:15 12:30 15 27.00 20.00 7.00 28.00 1.68
(in)(in)(in)(in/hr)(in/hr)
TEL-INF-17-2 9:00 9:15 15 60.00 45.44 14.56 58.25 1.61
9:15 9:30 15 45.44 32.13 13.31 53.25 1.98
9:30 9:45 15 60.00 43.06 16.94 67.75 1.92
1976320.21 N 9:45 10:00 15 43.06 31.06 12.00 48.00 1.87
510300.05 W 10:00 10:15 15 60.00 44.75 15.25 61.00 1.70
10:15 10:30 15 44.75 32.63 12.13 48.50 1.81
10:30 10:45 15 60.00 44.69 15.31 61.25 1.71
10:45 11:00 15 44.69 34.31 10.38 41.50 1.52
11:00 11:15 15 34.31 25.69 8.63 34.50 1.64
11:15 11:30 15 60.00 45.06 14.94 59.75 1.66
11:30 11:45 15 45.06 35.13 9.94 39.75 1.43
11:45 12:00 15 35.13 26.44 8.69 34.75 1.61
12:00 12:15 15 60.00 45.13 14.88 59.50 1.65
12:15 12:30 15 45.13 34.06 11.06 44.25 1.62
12:45 13:00 15 34.06 25.44 8.63 34.50 1.66
Notes:
3. The test borings do not extend to the GWT.
4. Depth of the GWT and SHWT are unknown.
7. Percolation rates consist of the total drop in head divided by the elapsed time (in/hr).
8. Infiltration rates consists of the percolation rate divided by a reduction factor (in/hr). This reduction factor is calculated according the the
formula in Attachment F (Michigan Method). These rates are considered to be a conservative estimate of the true infiltration rate. Please refer to the report for
a thorough explanation of methodology and assumptions.
Percolation and Infiltration Rates
Infiltration
RatesStartEnd
Elapsed
Time (min)
Observation Time Head at Beginning of
Observation Time
Head at End of
Observation Time
Total Head Loss
over Time Interval
Percolation
Rate
Elapsed
Time (min)
6. The distance from the top of the pipe to the basin invert (including pea gravel) was approximately 48 inches for TEL-INF-17-1 and 60 inches for TEL-INF-17-
1. The results of this test are not a direct reflection of the permeability (k) and are not a substitute for normal laboratory permeability testing.
Infiltration
RatesStartEnd
2. It is assumed that no conditions, such as a confining soil layer, exist at this site which would prevent vertical infiltration to the GWT.
5. A PVC pipe was driven approximately 6 inches below the basin invert in an attempt to force pure vertical infiltration during the test. More than likely, this
only prevented horizontal infiltration to an extent, with an unknown amount of horizontal infiltration taking place during the test. Therefore, a conservative
assumption was made that full horizontal infiltration took place (the water outside the pipe was in equilibrium with water inside the pipe), and the numbers
acquired during the test were in fact percolation rates. These rates are shown in the pecolation column above. These values were corrected to infiltration
rates using the procedure outlined in Attachment F of this report. Predicted infiltration rates can be seen in the last column in the tables above.
Observation Time Head at Beginning of
Observation Time
Head at End of
Observation Time
Total Head Loss
over Time Interval
Percolation
Rate
ATTACHMENT E
ATTACHMENT F
Michigan Method – Soil Infiltration Testing
ATTACHMENT F
Appendix E
Soil Infiltration Testing Protocol
Purpose of this Protocol
The soil infiltration testing protocol describes evaluation
and field testing procedures to determine if infiltration
BMPs are suitable at a site, as well as to obtain the
required data for infiltration BMP design.
When to Conduct Testing
The Site Design Process for LID, outlined in Chapter 5
of this manual, describes a process for site development
and application of nonstructural and structural BMPs. It
is recommended that soil evaluation and investigation
be conducted following development of a concept plan
or early in the development of a preliminary plan.
Who Should Conduct Testing
Soil evaluation and investigation may be conducted
by soil scientists, local health department sanitarians,
design engineers, professional geologists, and other
qualified professionals and technicians. The stormwater
designer is strongly encouraged to directly observe the
testing process to obtain a first-hand understanding of
site conditions.
Importance of Stormwater BMP
Areas
Sites are often defined as unsuitable for infiltration
BMPs and soil-based BMPs due to proposed grade
changes (excessive cut or fill) or lack of suitable areas.
Many sites will be constrained and unsuitable for infil-
tration BMPs. However, if suitable areas exist, these
areas should be identified early in the design process
and should not be subject to a building program that
precludes infiltration BMPs. Full build-out of site areas
otherwise deemed to be suitable for infiltration should
not provide an exemption or waiver for adequate storm-
water volume control or groundwater recharge.
Safety
As with all field work and testing, attention to all appli-
cable Occupational Safety and Health Administration
(OSHA) regulations and local guidelines related to
earthwork and excavation is required. Digging and
excavation should never be conducted without adequate
notification through the Michigan One Call system
(Miss Dig www.missdig.net or 1-800-482-7171 ). Exca-
vations should never be left unsecured and unmarked,
and all applicable authorities should be notified prior to
any work.
Infiltration Testing:
A Multi-Step Process
Infiltration testing is a four-step process to obtain the
necessary data for the design of the storm water manage-
ment plan. The four steps include:
1. Background evaluation
• Based on available published and site specific
data
• Includes consideration of proposed development
plan
Used to identify potential BMP locations and
testing locations
• Prior to field work (desktop)
2. Test pit (deep hole) observations
• Includes multiple testing locations
• Provides an understanding of sub-surface
conditions
• Identifies limiting conditions
3. Infiltration testing
• Must be conducted onsite
• Different testing methods available
4. Design considerations
• Determine suitable infiltration rate for design
calculations
• Consider BMP drawdown
• Consider peak rate attenuation
ATTACHMENT F
Step 1. Background evaluation
Prior to performing testing and developing a detailed
site plan, existing conditions at the site should be inven-
toried and mapped including, but not limited to:
• Existing mapped soils and USDA Hydrologic Soil
Group classifications.
• Existing geology, including depth to bedrock, karst
conditions, or other features of note.
• Existing streams (perennial and intermittent,
including intermittent swales), water bodies,
wetlands, hydric soils, floodplains, alluvial soils,
stream classifications, headwaters, and first order
streams.
• Existing topography, slope, drainage patterns, and
watershed boundaries.
• Existing land use conditions.
• Other natural or man-made features or conditions
that may impact design, such as past uses of site,
existing nearby structures (buildings, walls),
abandoned wells, etc.
• A concept plan or preliminary layout plan for
development should be evaluated, including:
0 Preliminary grading plan and areas of cut and
fill,
o Location of all existing and proposed water
supply sources and wells,
o Location of all former, existing, and proposed
onsite wastewater systems,
0 Location of other features of note such as utility
rights-of-way, water and sewer lines, etc.,
o Existing data such as structural borings, and
o Proposed location of development features
(buildings, roads, utilities, walls, etc.).
In Step 1, the designer should determine the potential
location of infiltration BMPs. The approximate location
of these BMPs should be on the proposed development
plan and serve as the basis for the location and number
of tests to be performed onsite.
Important: If the proposed development is located on
areas that may otherwise be a suitable BMP location,
or if the proposed grading plan is such that potential
BMP locations are eliminated, the designer is strongly
encouraged to revisit the proposed layout and grading
plan and adjust the development plan as necessary. Full
build-out of areas suitable for infiltration BMPs should
not preclude the use of BMPs for runoff volume reduc-
tion and groundwater recharge.
Step 2. Test pits (deep holes)
A test pit (deep hole) allows visual observation of the
soil horizons and overall soil conditions both hori-
zontally and vertically in that portion of the site. An
extensive number of test pit observations can be made
across a site at a relatively low cost and in a short time
period. The use of soil borings as a substitute for test
pits is strongly discouraged, as visual observation is
narrowly limited in a soil boring and the soil horizons
cannot be observed in-situ, but must be observed from
the extracted borings.
A test pit (deep hole) consists of a backhoe-excavated
trench, 2Y2-3 feet wide, to a depth of 6-7Y2 feet, or until
bedrock or fully saturated conditions are encountered.
The trench should be benched at a depth of 2-3 feet for
access and/or infiltration testing.
At each test pit, the following conditions are to be noted
and described. Depth measurements should be described
as depth below the ground surface:
• Soil horizons (upper and lower boundary),
• Soil texture, structure, and color for each horizon,
• Color patterns (mottling) and observed depth,
• Depth to water table,
• Depth to bedrock,
• Observance of pores or roots (size, depth),
• Estimated type and percent coarse fragments,
• Hardpan or limiting layers,
• Strike and dip of horizons (especially lateral
direction of flow at limiting layers), and
• Additional comments or observations.
The Sample Soil Log Form at the end of this protocol
may be used for documenting each test pit.
At the designer's discretion, soil samples may be
collected at various horizons for additional analysis.
Following testing, the test pits should be refilled with the
original soil and the topsoil replaced. A test pit should
never be accessed if soil conditions are unsuitable or
unstable for safe entry, or if site constraints preclude
entry. OSHA regulations should always be observed.
LID Manual fol' Michigan -Appendix E Page 438
ATTACHMENT F
It is important that the test pit provide information
related to conditions at the bottom of the proposed
infiltration BMP. If the BMP depth will be greater than
90 inches below existing grade, deeper excavation of
the test pit will be required. The designer is cautioned
regarding the proposal of systems that are significantly
deeper than the existing topography, as the suitability
for infiltration is likely to decrease. The design engineer
is encouraged to consider reducing grading and earth-
work as needed to reduce site disturbance and provide
greater opportunity for stormwater management.
The number of test pits varies depending on site condi-
tions and the proposed development plan. General
guidelines are as follows:
• For single-family residential subdivisions with
on-lot infiltration BMPs, one test pit per lot is
recommended, preferably within 100 feet of the
proposed BMP area.
• For multi-family and high-density residential
developments, one test pit per BMP area or acre is
recommended.
• For large infiltration areas (basins, commercial,
institutional, industrial, and other proposed land
uses), multiple test pits should be evenly distributed
at the rate of four to six pits per acre of BMP area.
The recommendations above are guidelines. Additional
tests should be conducted if local conditions indicate
significant variability in soil types, geology, water table
levels, depth and type of bedrock, topography, etc. Simi-
larly, uniform site conditions may indicate that fewer
test pits are required. Excessive testing and disturbance
of the site prior to construction is not recommended.
Step 3. Infiltration tests
A variety of field tests exists for determining the infil-
tration capacity of a soil. Laboratory tests are not
recommended, as a homogeneous laboratory sample
does not represent field conditions. Infiltration te~ts
should be conducted in the field. Infiltration tests
should not be conducted in the rain, within 24 hours
of significant rainfall events (>0.5 inches), or when the
temperature is below freezing.
At least one test should be conducted at the proposed
bottom elevation of an infiltration BMP, and a mini-
mum of two tests per test pit are recommended. Based
on observed field conditions, the designer may elect to
modify the proposed bottom elevation of a BMP. Person-
nel conducting infiltration tests should be prepared to
adjust test locations and depths depending on observed
conditions.
Methodologies discussed in this protocol include:
• Double-ring infiltrometer tests.
• Percolation tests (such as for onsite wastewater
systems).
There are differences between the two methods. A
double-ring infiltrometer test estimates the vertical
movement of water through the bottom of the test area.
The outer ring helps to reduce the lateral movement of
water in the soil from the inner ring. A percolation test
allows water movement through both the bottom and
sides of the test area. For this reason, the measured rate
of water level drop in a percolation test must be adjusted
to represent the discharge that is occurring on both the
bottom and sides of the percolation test hole.
Other testing methodologies and standards that are
available but not discussed in detail in this protocol
include (but are not limited to):
• Constant head double-ring infiltrometer.
• Testing as described in the Maryland Stormwater
Manual, Appendix D .1, using five-inch diameter
casing.
• ASTM 2003 Volume 4.08, Soil and Rock (I):
Designation D 3385-03, Standard Test Method for
Infiltration Rate of Soils in Field Using a Double-
Ring Infiltrometer.
• ASTM 2002 Volume 4.09, Soil and Rock (II):
Designation D 5093-90, Standard Test Method
for Field Measurement of Infiltration Rate Using
a Double-Ring Infiltrometer with a Sealed-Inner
Ring.
• Guelph permeameter.
• Constant head permeameter (Amoozemeter).
LID Manual for Michigan -Appendix E Page 439
ATTACHMENT F
Methodology for double-ring infiltrometer field test
A double-ring infiltrometer consists of two concentric
metal rings. The rings are driven into the ground and
filled with water. The outer ring helps to prevent diver-
gent flow. The drop-in water level or volume in the
inner ring is used to calculate an infiltration rate. The
infiltration rate is the amount of water per surface area
and time unit which penetrates the soils. The diameter
of the inner ring should be approximately 50-70 percent
of the diameter of the outer ring, with a minimum inner
ring size of four inches. Double-ring infiltrometer test-
ing equipment designed specifically for that purpose
may be purchased. However, field testing for storm-
water BMP design may also be conducted with readily
available materials.
Equipment for double-ring infiltrometer test:
Two concentric cylinder rings six inches or greater
in height. Inner ring diameter equal to 50-70 percent
of outer ring diameter (i.e., an eight-inch ring and a
12-inch ring). Material typically available at a hardware
store may be acceptable.
Water supply,
• Stopwatch or timer,
• Ruler or metal measuring tape,
• Flat wooden board for driving cylinders uniformly
into soil,
• Rubber mallet, and
• Log sheets for recording data.
Procedure for double-ring infiltrometer test
• Prepare level testing area.
• Place outer ring in place; place flat board on ring
and drive ring into soil to a minimum depth of two
inches.
• Place inner ring in center of outer ring; place flat
board on ring and drive ring into soil a minimum of
two inches. The bottom rim of both rings should be
at the same level.
• The test area should be presoaked immediately
prior to testing. Fill both rings with water to water
level indicator mark or rim at 30-minute intervals
for one hour. The minimum water depth should be
four inches. The drop in the water level during the
last 30 minutes of the presoaking period should be
applied to the following standard to determine the
time interval between readings:
0 If water level drop is two inches or more, use
IO-minute measurement intervals.
0 If water level drop is less than two inches, use
30-minute measurement intervals.
• Obtain a reading of the drop in water level in the
center ring at appropriate time intervals. After each
reading, refill both rings to water level indicator
mark or rim. Measurement to the water level in the
center ring should be made from a fixed reference
point and should continue at the interval determined
until a minimum of eight readings are completed or
until a stabilized rate of drop is obtained, whichever
occurs first. A stabilized rate of drop means a
difference of 14 inch or less of drop between the
highest and lowest readings of four consecutive
readings.
• The drop that occurs in the center ring during the
final period or the average stabilized rate, expressed
as inches per hour, should represent the infiltration
rate for that test location.
Methodology for percolation test
Equipment for percolation test
• Post hole digger or auger,
• Water supply,
• Stopwatch or timer,
• Ruler or metal measuring tape,
• Log sheets for recording data,
• Knife blade or sharp-pointed instrument (for soil
scarification),
• Course sand or fine gravel, and
• Object for fixed-reference point during
measurement (nail, toothpick, etc.).
LlD Manual for Michigan -Appendix E Page 440
ATTACHMENT F
Procedure for percolation test
This percolation test methodology is based largely on
the criteria for onsite sewage investigation of soils. A
24-hour pre-soak is generally not required as infiltra-
tion systems, unlike wastewater systems, will not be
continuously saturated.
• Prepare level testing area.
• Prepare hole having a uniform diameter of 6-10
inches and a depth of 8-12 inches. The bottom and
sides of the hole should be scarified with a knife
blade or sharp-pointed instrument to completely
remove any smeared soil surfaces and to provide
a natural soil interface into which water may
percolate. Loose material should be removed from
the hole.
• (Optional) Two inches of coarse sand or fine gravel
may be placed in the bottom of the hole to protect
the soil from scouring and clogging of the pores.
• Test holes should be presoaked immediately prior
to testing. Water should be placed in the hole to a
minimum depth of six inches over the bottom and
readjusted every 30 minutes for one hour.
• The drop in the water level during the last 30
minutes of the final presoaking period should be
applied to the following standard to determine the
time interval between readings for each percolation
hole:
0 If water remains in the hole, the interval for
readings during the percolation test should be 30
minutes.
0 If no water remains in the hole, the interval
for readings during the percolation test may be
reduced to 10 minutes.
• After the final presoaking period, water in the hole
should again be adjusted to a minimum depth of
six inches and readjusted when necessary after
each reading. A nail or marker should be placed at
a fixed reference point to indicate the water refill
level. The water level depth and hole diameter
should be recorded.
• Measurement to the water level in the individual
percolation holes should be made from a fixed
reference point and should continue at the interval
determined from the previous step for each
individual percolation hole until a minimum of
eight readings are completed or until a stabilized
rate of drop is obtained, whichever occurs first.
A stabilized rate of drop means a difference of V<i
inch or less of drop between the highest and lowest
readings of four consecutive readings.
• The drop that occurs in the percolation hole during
the final period, expressed as inches per hour,
should represent the percolation rate for that test
location.
• The average measured rate must be adjusted to
account for the discharge of water from both
the sides and bottom of the hole and to develop
a representative infiltration rate. The average/
final percolation rate should be adjusted for each
percolation test according to the following formula:
Infiltration Rate= (Percolation Rate)/(Reduction
Factor)
Where the Reduction Factor is given by**:
With:
R _ 2d1 -D,d + 1 !-DIA
d 1 =Initial Water Depth (in.)
D,d =Average/Final Water Level Drop (in.)
DIA= Diameter of the Percolation Hole (in.)
The percolation rate is simply divided by the reduc-
tion factor as calculated above or shown in Table E.1
below to yield the representative infiltration rate. In
most cases, the reduction factor varies from about two
to four depending on the percolation hole dimensions
and water level drop -wider and shallower tests have
lower reduction factors because proportionately less
water exfiltrates through the sides.
** The area reduction factor accounts for the exfiltra-
tion occurring through the sides of percolation hole. It
assumes that the percolation rate is affected by the depth
of water in the hole and that the percolating suiface
of the hole is in uniform soil. If there are significant
problems with either of these assumptions then other
adjustments may be necessary.
LID Manual for Michigan -Append.ix E Page 441
ATTACHMENT F
Step 4. Use design considerations
provided in the infiltration BMP.
Table E.1
Sample Percolation Rate Adjustments
6
8
6
10
6
8
8
10
6
8
10
10
0.1 3.0
0.5 2.9
2.5 2.6
0.1 3.7
0.5 3.6
2.5 3.3
0.1 4.3
0.5 4.3
2.5 3.9
0.1 2.5
0.5 2.4
2.5 2:r
0.1 3.0
0.5 2.9
2.5 2.7
0.1 3.5
0.5 3.4
2.5 3.2
0.1 2.2
0.5 2.2
2.5 2.0
0.1 2.6
0.5 2.6
2.5 2.4
0.1 3.0
0.5 3.0
2.5 2.8
LID Manual for Michigan -Appendix E Page 442
ATTACHMENT F
Additional Potential Testing -Bulk Density
Bulk density tests measure the level of compaction of a soil, which is an indicator of a soil's ability to absorb rain-
fall. Developed and urbanized sites often have very high bulk densities and, therefore, possess limited ability to
absorb rainfall (and have high rates of stormwater runoff). Vegetative and soil improvement programs can lower the
soil bulk density and improve the site's ability to absorb rainfall and reduce runoff.
Macropores occur primarily in the upper soil horizons and are formed by plant roots (both living and decaying), soil
fauna such as insects, the weathering processes caused by movement of water, the freeze-thaw cycle, soil shrinkage
due to desiccation of clays, chemical processes, and other mechanisms. These macropores provide an important
mechanism for infiltration prior to development, extending vertically and horizontally for considerable distances.
It is the intent of good engineering and design practice to maintain these macropores when installing infiltration
BMPs as much as possible. Bulk density tests can help determine the relative compaction of soils before and after
site disturbance and/or restoration and should be used at the discretion of the designer/reviewer.
Soi/ Test Pit Lag Sheet
Project:
Name:
Location:
Test Pit#
Horizon Depth
(In.)
Color
REDOX FEATURES
Abundance
Few ........ < 2%
Common .. 2-20%
Many ...... > 20%
Contrast
faint
Red ox
Features
hue & chroma of matrix
and redox are closely related.
distinct
matrix & redox features vary
1 -2 units of hue and several unites
of chroma & value.
prominent
Matrix & redox features
Texture
vary several units in hue, value & chroma
HORIZONS
0 -organic layers of decaying plant and
animal tissue (must be greater than 12-
18% organic carbon, excluding live roots).
A (topsoil) -mineral horizon at or near
the surface in which an accumulation of
humified organic matter is mixed with the
mineral material.
Date:
Soil Series:
Other:
Notes Boundary
(if applicable)
COARSE FRAGMENTS(% of profile)
15-35% 35-65% >65%
gravelly very gravelly extremely gravelly
channery very channery extremely channery
cobbly very cobbly extremely cobbly
flaggy very flaggy extremely flaggy
stony very stony extremely stony
BOUNDARY
Distinctness
abrupt ... < 1" (thick) gradual .. 2.5 -5"
c/ear ..... 1 -2.5" diffuse .... > 5
Topography
smooth -boundary is nearly level
wavy-pockets with width > than depth
irregular -pockets with depth > than width
B (subsoil) -mineral horizon with evidence of
pedogenesis or llluviation (movement into the
horizon).
C (substratum) -the un-weathered geologic
material the soil formed in. Shows little or no
sign of soil formation.
E -mineral horizon which the main feature is loss of silicate clay,
iron, aluminum. Must be underlain by a B {alluvial) horizon.
l...ilD Manual fo11Michigan -Appendix B Page 443
ATTACHMENT F