CC - Storm Drainage Report Phases 3 & 412
Storm Drainage Report
for
BRICKYARD SUBDIVISION
PHASES 3&4
Prepared by: John Carpenter, P.E.
October 31, 2017
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T -O ENGINEERS
Project No. 170005
CONSULTING ENGINEERS, SURVEYORS AND PLANNERS
332 NORTH BROADMORE WAY
NAMPA, IDAHO 83687
208-442-6300 • FAX 208-466-0944
STORM DRAINAGE SUMMARY
The proposed Brickyard Subdivision No. 3 & 4 is located northeast of the intersection of N. Eagle
Road and E. Ustick Road. More specifically, it is located on N. Centrepoint Way, south of E.
Jasmine Lane and north of Hobby Lobby. Brickyard Subdivision consists of 59 multi -family lots,
2 mixed use lots, multiple park areas, underground utilities, attached curb and gutter, and street
paving. The multi -family buildings consist of a mix of 2 and 3 story individual units. Each
building cluster will have roof drains connected to storm drainage pipe that conveys the storm
water to seepage beds.
The site is currently vacant and not being used as farm land. The property historically drains to a
ditch in the center of the property, which is routed to a gravity irrigation system that transports
water off the property at the northwest corner. (See Historical Drainage Map, attached). The site
lies within the Settlers Irrigation District and will be supplied irrigation from the Layton Lateral
which is fed by a pump station. The City of Meridian will act as the secondary source of
irrigation. N. Centrepoint Way currently has a seepage bed that is owned and maintained by
ACHD, located on the east side of the road in Phase 1.
Phases 1 and 2 of the subdivision as well as the clubhouse located in the common area in Phase 4,
are expected to be constructed prior to the construction of Phases 3 & 4. The two seepage beds
designed for Phases I and 2 are to be constructed within the boundaries of Phases 3 and 4. The
additional storm systems, as detailed in this report and shown on the Phase 3 and 4 construction
drawings are for the additional storm water storage from the additional Phases.
Brickyard Subdivision No. 3 & 4 consists of five basins, see attached Basin Map.
Phase 3: Basin 3A includes runoff from roof drains, driveways, pavements, parking spaces and
landscaping for the residential building and one of the mixed use buildings. This basin also
includes a portion of the existing private drive between Brickyard Subdivision and Hobby Lobby.
Stormwater from this basin is collected from catch basins in the curb of the parallel parking along
the Hobby Lobby private drive and from an area drain in the parking area, and routed to a sand
and grease trap to Seepage Bed 3A, located under the parking area. Seepage Bed 3A is designed
to store and infiltrate the volume from the 100 year storm.
Basin 3B includes runoff from another portion of the Hobby Lobby private drive, and the parking
area between the mixed use buildings. Basin 3B drains to catch basins in the curb of the private
drive and parking area and is routed to a sand and grease trap and ultimately to Seepage Bed #4,
located in the parking area. Seepage Bed 313 is designed to store and infiltrate the volume from
the 100 year storm.
Basin 3C contains runoff from a portion of the westernmost mixed use building and the Hobby
Lobby private drive. This area mitigates for the area that previously drained to the existing system
in the private drive. Existing area draining to storm system is approximately 0. 19 acres and the
proposed area to drain to the system is approximately 0. 16 acres. The existing catch basin will be
extended to the new gutter line in addition to a catch basin added at the eastern parallel parking
area.
Phase 4: Basin 4A contains runoff from Streets F&G and a portion of Street E as well as
landscaping from the park area and roof drains which will connect to area drains and piping in the
park area. Runoff collected in catch basins from the roads will be routed to sand and grease traps.
Runoff from the park areas and roof drain piping will be routed to area drains and pipes within
the park area. All Stormwater from this basin will be routed to Seepage Bed 4A. Seepage Bed 4A
i is located within the park area and is designed to contain the 25y car storm. For storm events
i
Brickyard Subdivision No. 1 & 2
Drainage Calculations
greater than the 25 -year event, water will back up through the area drains located at the end of the
seepage bed and water will be stored in the park area. The high water elevation is approximately
261 6.0.
Basin 4B contains the southern building on Street G. Runoff from the roof drains and landscaping
in this basin will be routed to Seepage Bed 4B in the southwest corner of the project. Seepage
Bed 4B has been sized to accommodate the 25 year storm for this basin, any additional water will
overflow to the street and ultimately Seepage Bed 4A. All water from the driveways for this
building will also be routed to the streets and to Seepage Bed 4A.
Basin 4C contains the northwest half of Street E. Storm water from this basin will be routed to the
catch basin located at the west end of Street 3, and will be treated by a sand and grease trap and
will be stored and infiltrated through Seepage Bed 4C. Seepage Bed 4C is designed to store and
infiltrate the volume from the 100 year storm.
Flood events will be routed to the existing gravity irrigation system in the north west corner of the
project. See Flood Routing Map attached.
GROUNDWATER
The attached geotechnical investigation identifies several test pits that have been excavated to
determine soil conditions as well as groundwater elevation. No groundwater was encountered.
Contractor shall contact the project engineer for observations if groundwater is encountered
during construction.
DESIGN CRITERIA
• Rational method is used for calculating the peak runoff flows: Q v C * I * A
• Runoff coefficients based on land use from Ada County Highway District Standards.
• Percolation rate at 8 in/hr used in design. Geotechnical report recommends using a
percolation rate of 8 in/hr. At the time of construction project engineer will observe soil
conditions for concurrence with design. Owner's geotechnical engineer will verify soils if
conditions do not appear consistent with design
APPENDICES
• Vicinity Map
• Percolation Bed Sizing Calculations
• Drainage Basin Map
• Soils Report
LA170005\40_final DcsignNorm Report\Phase 3&4\170005 Slonn Drainage Report PH 3 & 4.doe I
Brickyard Subdivision Phase 3 and 4
Hydrology Report and Drainage Calculations
Basin 3A- Seepage Bod 3A
Total Area=
Run-off Coeffecient=
Historic Flow Rate
Percolation Rate
0.29 Acres
0.9
0 cfs `
8 in/hr
Effective depth
Width (Il)-
Length (11)-
pipe Size
Percolation Area (sq ti)-
Storage Vohnne (cl)=
10
10
25
I
250
IUUU
Detention FacilityNo. 1
I7Ui�l14rit (111111
I( N) yr Intensity
(11VI11I AICA (acr,>)
historical
H-11mc Q II.. Kaie
CIA e60 (cls)
Poc Kate
(111/br)
I'm M.
Kate(Q.)
(cis)
Runoff
Ncl6lr,10te Volume(VK)
(cf, ) (en
Its%KegN
fit Satliment
stitaie CI
As:lilabtc Kcg'd Ab -c
Savage (itound
Ch Mora gC
Time to
Percolate II"
1 III)
10
3.11 0.29
0.81 0.00
8.00
0.05
0.77
459
528
1000 472
3
IS
2.62 0.29
0.68 0.00
8.00
0.05
0.64
574
660
1000 -340
3
30
1.82 0.29
0.48 0.00
8.00
0.05
0.43
772
1 887
1000 -113
5
60
1.15 0.29
0.30 0.00
8.00
0.05
0.25
914
1051
1000 51
5
120
0.66 0,29
0.17 0.00
8.00
0.05
0.13
907
1043
1000 43
5
180
0.48 0.29
0.13 0.00
8.00
0.05
0.08
853
981
1000 -19
5
360
0.30 0.29
0.08 0.00
8.00
0-05
0.03
691
795
1000 -205
4
720
0.19 0,29
0.05 0.00
8.00
OA5
0.00
142
1(A
1000 -836
1
1440
1 0.12 0.29
0.03 U,UU
8A0
0.05
-0.01
-1294
-1188
1000 -2488
-8
Brickyard Subdivision Phase 3 and 4
Hydrology Report and Drainage Calculations
Basin 3B- Seepage Bed 3B
Total Area=
Run-off Coeffecient=
Historic Flow Rate
Percolation Rate
0.57 Acres
0.9
0 cis '
8 In/hr
F.ifeclive depth
Width p11-
Length (11)-
Pipe Size
I'ercolation Area (sq n)-
Storage Volume (ei)=
10
10
50
t
Soo
2000
Detention FacilityNo. 1
Duranon(mm)
14III yT Itnensity
NOO Atm(acme)
Flow Rate Q
-CIA(c(sl
Ilistmical
Flow Rate
(cfs)
Pere Irate
(in hr
Pete Ilow
Rate (Qx)
(ds>
Runoff
Net Flow Rate Volume (VK)
cts c(
1I5%Rey'd
fur Sediment
St<ua,e(Cl)
A4ailable Rnfd Above
Storage (tround
o) storage
Tintc to
Percolate (,Ir
1 (Inl
to
3.11 0.57
1.60
0.00
8.00
0.09
1.50
902
1037
2000 -96:3
3
15
2.62 0.57
1.34
0.00
8.00
0.09
1.25
1126
1295
2000 -705
3
30
1.82 0.57
1 0.93
0.00
8.00
0.09
0.54
1 1514
1741
2000 1 -259
5
60
1.15 0.57
0.59
0.00
8.00
0.09
0.50
1790
2059
2000 59
5
120
0.66 0,57
0.34
0.00
8.00
0.09
0.25
1771
2037
2000 37
5
180
0.48 0.57
0.25
0.00
RM
0.09
0.15
1659
1909
2000 •92
5
360
0.30 0.57
0.15
0,00
8.00
0.09
0.06
1324
1523
2000 -477
4
720
0.19 0.57
0.10
0.00
8.00
0.09
0.00
211
242
2000 -1758
I
1440
1 0.12 0.57
0.06
0.00
8.00
0.09
-0.03
-2681
-3083
2000 -5083
8
Brickyard Subdivision Phase 3 and 4
Hydrology Report and Drainage Calculations
Basin 4A -Seepage Bed 4A- 25 year
Total Area=
Run-off Coeffecient=
Historic Flow Rate
Percolation Rate
4.43 Acres
0.62
0 cis
8 in/hr
4.43 Acres
0.62
0 cis
8 in/hr
Effective depth
Width (ft)-
Length (ft)=
Iaipc Size
Percolation Area (sq f0-
Storage Vol a is (cl)=
Effective depth
Width (0)--
Length (11)-
Pipe Size
Percolation Arca (sq it)--
Storage Volume let)-
8.3
40
60
I
2400
8000
8.3
40
60
I
2,100
8000
Detention Facili No. 1
Detention Facility No. 2
Duratunl(unn)
25 yr Intensity
(itv'fi0 Area (aems)
Historical
Flow Rate Q How Rate
--CIA cfs) (cfs)
)'ere [tate
((in hr)
Pcrc Plow
Rale (Q.)
cl')
Runoff
Net Idow Bate Volume (Vu)
(cfs ) let)
IIS;»Rev'd
tot Sediment
Stora c eO
Avadable
Stnragc
(cf)
Rajd Above
Ground
Storate
Tone to
Perutlate (Te
1 out
10
2.37 4A3
6.51 0.00
8.00
0.44
6.06
3639
4185
8000
-3815
2
3
15
2.00 4.43
5.49 0.00
8.00
0.44
5.05
4544
5225
8000
.2775
3
4
30
1.39 4.43
1 3.82 0.00
8.00
0.44
3.37
6072
6983
8000
1 -1017
4
5
60
0.88 4.43
2.42 0.00
8.00
0.44 _
1.97
7101
8166
8000
166
4
6
120
0.50 4.43
1.37 0.00
8.00
0.44
0.93
6688
7691
8000
-309
4
6
180
0.37 4.43
1.02 0.00
8.00
0.44
0.57
6175
7102
8000
-898
4
6
360
0.23 4.43
0.63 0.00
8.00
0.44
0.19
4045
4652
8000
-3348lj
8000 1428
S
720
0.15 4.43
0.41 0.00
8.00
0.44
-0.03
-1402
-1612
8000
-9612
8000 4154
2
1440
0.09 4.43
0.25 0.00
8.00
0.44
-0.20
-7042
-19599
8000
-27599
8000 19412
Basin 4A
Total Areart
Run-off Coeffecient=
Historic Flow Rate
Percolation Rate
4.43 Acres
0.62
0 cis
8 in/hr
Effective depth
Width (0)--
Length (11)-
Pipe Size
Percolation Arca (sq it)--
Storage Volume let)-
8.3
40
60
I
2,100
8000
Detention Facility No. 2
Dul.tiun Onin
ton-yv lni-ity
itv ") Arca(acres)
Plow Rate Q
=CIAWS)
16storical
Flow Rate
(era
Pcrc Rate
imhr)
Nlc riotc
Ralc (Qnt
Nk)(Cts
Runoff
Net Plow Rate V01ume (Vn)
) (c
It 5%Rev'd
!x Sediment
storam (eq
Mailable Re<jd Above
Stnragc Ground
(cf) Storage
'rime to
1'erco)aw (Te
) (hr)
10
3.11 4.43
8.54
0.00
8.00
0:14
8.10
4858
5587
8000 -2413
3
Is
2.62 4.43
7.20
0.00
8.00
0.44
6.75
6076
6988
8000 .1012
4
30
1.82 4.43
5.00
0.00
8.00
0.44
4.55
8198
1 9428
8000 1428
5
60
1.15 4.43
3.16
0.00
8.00
0.44
2.71
9771
11237
8000 3237
6
120
0,66 4.43
1.81
0.00
8.00
0.44
1.37
9852
11330
8000 3330
6
180
0.48 4.43
1.32
0.00
8.00
0.44
0.87
9438
10854
8000 2854
6
360
0.30 4.43
0.82
0.00
8.00
0.44
0.38
8198
9428
8000 1428
S
720
0.19 4.43
0.52
0.00
8.00
0.44
0.08
3344
3846
8000 4154
2
1440
0.12 4.43
0.33
0.00
8.00
0A4
-0.11
-9923
-11412
8000 19412
-6
Seepage Bed 4A Is designed to store the approximate volume of the 1 hour, 25 year storm. Therefore, greater storm events will cause ponding in the park area
and the low point of Street F. The storm runoff will ultimately drain and percolate through the seepage bed.
Brickyard Subdivision Phase 3 and 4
Hydrology Report and Drainage Calculations
Seepage Bed 4B
Total Area=
Run-off Coeffecient=
Historic Flow Rate
Percolation Rate
0.14 Acres
0.9
0 cis '
8 in/hr
Fffeetive depth
Width (n),-
Length (0)-
Pipe Size
Percolation ,area (sq fl)-
Stora a Volume (cl)-
5
8
20
t
160
320
Detention Facili No. 9
nuculon (min
21)f Inienity
11011) Area (acres
Ifwurinal
flue Rate Q Pim. Rule
- CIA (cis) (cls)
fere Rate
(n'hr)
Pere Plme
Ram (Qa)
WO
Runoff
No Ffmv Rate Vafume (Vn)
WS 1 nt
I IS o Req'd
nor Scdimcni
Stura a el
A,;nhble Refd Above
Storage (ia.und
Wi Stowe
"Pmtc to
Percolate (it
i tilt)
10
2.37 0.14
0.30 0.00
5.00
0.03
0.27
)61
186
320 -134
2
IS
2.00 0.14
0.25 0.00
9.00
0.03
0.22
200
230
320 -90
2
30
1.39 0.14
0.18 0.00
8.00
1 0.03
0.15
1 262
301
320 1 -19
2
60
0.88 0.14
0.11 0.00
8.00
0.03
0.08
293
336
320 16
3
120
0.50 0.14
0.06 0.00
8.00
0.03
0.03
240
276
320 •44
2
180
0.37 0.14
11.05 0.00
8.00
0.03
0.02
183
211
320 -109
2
360
0.23 0.14
0.03 0.00
8.00
0.03
0.00
-14
-16
320 -336
0
720
0.15 0.14
0.02 0.00
9.00
0.03
-0.01
464
-533
320 -853
-4
)4-00
0.09 0.14
0A1 1 0.00
8.00
0.03
-0.02
-1580
-1817
320 -2137
-15
Brickyard Subdivision Phase 3 and 4
Hydrology Report and Drainage Calculations
Basin 4C -Seepage Bed 4C
Total Area=
Run -oft Coeffecient=
Historic Flow Rate
Percolation Rale
0.73 Acres
0.69
0 cis '
8 in/hr
Fffective depth
Width (A)-
Length (A)=
Pipc Size
Percolation Arca (sq li)-=
Storage V01un1c (CO=
10
10
50
I
500
2000
Detention FacilityNo. 1
Uumtion (min(iwhr
IIN)yrlmeneily
Arca(mo)
flow Rate Q
-CIA(ctil
liwotieal
Flow Rate
(cfs
Pew hate
mitt
r'crc Pton
Rate (Qa)
(d'si(cis
Ruttuff
Net Flnw Rale Volunm(VO
) rt)
IIRett'd
for Sediment
Storw cn
Acailahlc Rejd Abmc
Stmage Oraund
(G) SWrauo
Tare
Peturlate
)
to
ITr
hr
10
3.11 O03
1.57
0.00
8.00
0.09
1,47
884
1017
2000 -983
3
15
2.62 0.73
1.32
0.00
8.00
0.09
1.23
1104
1270
2000 .730
3
30
1.82 0.73
0.92
0.00
8.00
1 0.09
0.82
1 1483
1706
2000 1 -294
4
60
1.15 0.73
0.58
0.00
8.00
0.09
0.49
1752
2015
2000 15
5
120
0.66 0.73
0.33
0.00
8.00
0.09
0.24
1727
1986
2000 .14
5
180
0.48 0.73
0.24
0.00
8.00
0.09
0.15
1611
1853
2000 -147
5
360
0.30 0.73
0.15
0.00
8.00
0.09
0.06
1264
1454
2000 -546
4
720
0J9 0.73
0.10
0.00
8.00
0109
WOO
134
155
2000 -1845
1)
1440
1 0.12 0.73
0.06
0.05
8.110
0.09
-0.03
-2778
.3194
2000 -5194
.8771
Brickyard Subdivision Phase 3 and 4
Hydrology Report and Drainage Calculations
Brickyard Subdivision Phase 3 & 4 - SAND & GREASE TRAP SIZING
Sand/Grease
Trap No.
C
1 (100 year)
A
Flow (Q)
El
0.5
2.6
0.73
0.95
E2
0.63
2.6
0.74
1.21
F1
0.6
2.6
0.93
1.45
H1
0.9
2.6
0.29
0.68
H2
0.9
2.6
0.57
1.33
SGT E1 1000 GAL)
Sand & Grease Trap Throat Velocity
S/G #E1
SG Trap
Size (gal)
No. of
Traps (ea)
Baffle
Width (in)
Inside
Width (in)
100 -yr
Peak SG Trap Velocity
Flow (cfs) (fps)
Check
1000
1
1000
1
20
51
0.95 0.13
OK
Baffle Inside Peak SG Trap Velocity
I
Sand & Grease Trap Detention Time
SG Trap
S/G #E1 Size (gal)
No. of
Traps (ea)
100 -yr
Peak
Flow (cfs)
Bottom of
Inv out EI Box EI
Stored Volume Travel
(ftA3) Time (s) Check
1 1000
1
0.95
2406.75 2402.75
70.89 74.70 OK
SGT F1 1000 GAL
Sand & Grease Trap Throat Velocity
SGT E2 (1000 GAL
SG Trap
Size (gal)
No. of
Traps (ea)
Baffle
Width (in)
Inside
Width in
Sand & Grease Trap Throat Velocity
SG Trap Velocity
(fps) Check
1000
1
1000
100 -yr
20
61.5
SG Trap
No. of
Baffle Inside Peak SG Trap Velocity
I
Sand & Grease Trap Detention Time
S/G #E2 Size gal
Traps (ea) Width (in) Width (in) Flow (cfs)
(fps)
Check
1
1000
1
20 51
1.21
1000
0.17
OK
2406.00
2400.92
227.81
Sand & Grease Trap Detention Time
100 -yr
SG Trap
No. of
Peak
Bottom of
Stored Volume
Travel
S/G #E2 Size gal
Traps ea
Flow (cfs)
Inv out EI
Box EI
(ft^3)
Times
Check
1 1000
1
1.21
2406.75
2402.75
70.89
58.48
OK
SGT F1 1000 GAL
Sand & Grease Trap Throat Velocity
S/G #F1
SG Trap
Size (gal)
No. of
Traps (ea)
Baffle
Width (in)
Inside
Width in
100 -yr
Peak
Flow cfs
SG Trap Velocity
(fps) Check
1000
1
1000
1
20
61.5
1.45
0.17 OK
Bottom of
Box EI(ft-3)
Sand & Grease Trap Detention Time
S/G #F1
SG Trap
Size (gal)
No. of
Traps (ea)
100 -yr
Peak
Flow (cfs)
Inv out EI
Bottom of
Box EI
Stored Volume
(ft^3)
Travel
Time (s) Check
1
1000
1
1.45
2406.00
2400.92
227.81
157.02 OK
SGT H1 1000 GAL
Sand & Grease Trap Throat Velocity
S/G #H1
SG Trap
Size (gal)
No. of Baffle
Traps (ea) Width (in)
100 -yr
Inside Peak
Width in Flow cfs
SG Trap Velocity
(fps) Check
1
1000
1 20
61.5 0.68
0.08 OK
Sand & Grease Trap Detention Time
100 -yr
GTap No. of Peak
SGTap
S/G #H1 Size (gal) No.
(ea) Flow (cfs)
1 1000 1 0.68
Inv out EI
Bottom of
Box EI(ft-3)
Stored Volume Travel
Time (s)
Check
2406.00
2400.92
227.81 335.70
OK
Brickyard Subdivision Phase 3 and 4
Hydrology Report and Drainage Calculations
SGT H2 1000 GAL
Sand & Grease Trap Throat Velocity
S/G #H2
SG Trap No. of
Size (gal) Traps (ea)
Baffle
Width (in)
Inside
Width (in)
100 -yr
Peak
Flow (cfs)
SG Trap Velocity
(fps)
Check
1
1000 1
20
61.5
1.33
0.16
OK
Sand & Grease Trap Detention Time
S/G #H2
SG Trap No. of
Size (gal) Traps (ea)
100 -yr
Peak
Flow (cfs) Inv out El
Bottom of
Box EI
Stored Volume
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9
GEOTECHNICAL EVALUATION FOR
"BRICKYARD" - A 15+ ACRE MULTI -FAMILY
RESIDENTIAL AND COMMERCIAL DEVELOPMENT
LOCATED ON THE SOUTHEAST CORNER OF
N. CENTREPOINT WAY AND W. JASMINE LANE,
MERIDIAN, IDAHO
June 12, 2017
GTI -Project No. 1867-ID3
Prepared For:
Land Development Partners, LLC.
4685 S. Highland Dr., Suite 202
Salt Lake City, Utah 84117
TABLE OF CONTENTS
SCOPEOF SERVICES.......................................................................................................................................... I
SITEDESCRIPTION............................................................................................................................................. 2
PROPOSEDDEVELOPMENT............................................................................................................................2
FIELDSTUDIES......................................................................................................................................................2
REGIONALGEOLOGY......................................................................................................................................2
SITESOILS..............................................................................................................................................................3
ArtificialFill...................................................................................................................................................... 3
NativeAlluvial Soils........................................................................................................................................ 3
SURFACE& GROUND WATER......................................................................................................................4
TECTONIC FAULTING AND REGIONAL SEISMICITY............................................................................4
SecondarySeismic Constraints.................................................................................................................... 4
RESULTSOF LABORATORY TESTING......................................................................................................... 5
CONCLUSIONS................................................................................................................................................... 5
RECOMMENDATIONS - EARTHWORK CONSTRUCTION................................................................. 5
General............................................................................................................................................................. 5
Demolition....................................................................................................................................................... 6
Removals/Processing - General................................................................................................................... 6
TransitionalPads............................................................................................................................................. 7
ExcavationDifficulty....................................................................................................................................... 7
FillPlacement...................................................................................................................................................7
StructuralFill and Import Soils.................................................................................................................... 7
Observationand Testing............................................................................................................................... 8
GroundWater................................................................................................................................................8
EarthworkSettlements.................................................................................................................................. 8
SlopeStability................................................................................................................................................... 8
RECOMMENDATIONS—
FOUNDATIONS9
.................................................................................................
General.............................................................................................................................................................
9
9
Conventional Foundation
Recommendations..........................................................................................
FoundationSettlement
................................................................................................................................
PAVEMENTSECTIONS.................................................................................................................................... I
Pavement Construction and Maintenance.............................................................................................. I I
OTHERRECOMMENDATIONS....................................................................................................................13
SiteImprovements........................................................................................................................................ 13
Landscape Maintenance and Planting........................................................................................................ 14
SoilCorrosion............................................................................................................................................... 14
TrenchExcavation........................................................................................................................................ 14
OnsiteUtility Trench Backfill..................................................................................................................... 14
Drainage.......................................................................................................................................................... 15
PLANREVIEW..................................................................................................................................................... 15
LIMITATIONS...................................................................................................................................................... 15
Enclosures:
Figure #1, Site Vicinity Map
Figure #2, Site Exploration Plan
Figure #3, Proposed New Development Site Plan
Appendix A, References
Appendix B, Test Pit Logs
Appendix C, Field Test Results
Appendix D, Laboratory Test Results
GeoTek, Inc.
320 East Corporate Drive Suite 300 Meridian, ID 83642-3511
(208) 888-7010 (208) 888-7924 www.geotekusa.com
June 12, 2017
Project No. 1867-ID3
LAND DEVELOPMENT PARTNERS, LLC
4685 S. Highland Dr., Suite 202
Salt Lake City, Utah 84117
Attention: Mr. James Doolin
Subject: Geotechnical Evaluation for "Brickyard" - a 15+ Acre Multi -Family residential and
Commercial Development Located on the Southeast Corner of N. Centrepoint Way
and W. Jasmine Lane, Meridian, Idaho
In accordance with your request, GeoTek, Inc. (GTI) has completed a geotechnical evaluation of the
subject property for the construction of a mixed-use development (residential/commercial) and
associated improvements. The purpose of our study was to evaluate the soils underlying the site and to
provide recommendations for project design and construction based on our findings. This report
outlines the geotechnical conditions of the site based on current data, and provides earthwork and
construction recommendations with respect to those conditions.
SCOPE OF SERVICES
The scope of our services has included the following:
Review of soils and geologic reports and maps for the site (Appendix A).
2. Site reconnaissance.
3. Review of aerial photographs.
4. Excavating and logging of five (5) exploratory test pits (Appendix B).
5. Obtaining samples of representative soils, as the exploratory test pits were advanced.
6. Performing laboratory testing on representative soil samples (Appendix D).
7. Assessment of potential geologic constraints.
8. Engineering analysis regarding foundation design/construction, foundation settlement, and site
preparation.
9. Preparation of this report.
GEOTECHNICAL I ENVIRONMENTAL I MATERIALS
BRICKYARD JUNE 12, 2017
LAND DEVELOPMENT PARTNERS, LLC PAGE 2
PROJECT NO. 1867-ID3
SITE DESCRIPTION
The project site consists of irregularly shaped parcels totaling approximately 15± acres that is
generally bound by E. Jasmine Lane to the north, Boise Family Psychology, a private business, and
undeveloped land bordering Eagle Road to the east, N. Centrepoint Way to the south, and a
residential development to the west in the City of Meridian, Ada County, Idaho (Figure 2). Access to
the Site is possible from N. Centrepoint Way. The property is mainly undeveloped land with a few
piles of artificial fill. A recently constructed roadway, extending N. Centrepoint Way, bisects the site.
An existing east -west trending natural drainage ditch exists along the southeastern border of the Site.
From topographic maps, the site's elevation is approximately 2,613+ to 2,623+ feet above mean sea
level. Natural drainage at the Site is interpreted to be downward to the south-southwest, conforming
to the natural topography in the area. No standing water was observed on the Site on the date of our
reconnaissance.
PROPOSED DEVELOPMENT
It is our understanding that site development would consist of performing typical cut and fill
earthwork to attain the desired graded configuration (s) for the construction of multiple one to two-
story residential mixed with commercial structures with associated improvements. It is further
assumed that final site grade will be within 3 feet of existing site grade. Reference the attached
Proposed New Development Concept Plan (Figure 3), Concept Plan — Centrepoint and Jasmine, dated
4-12-17, provided by T -O Engineers for use in development of this Geotechnical Evaluation.
FIELD STUDIES
Subsurface conditions at the site were explored by using a rubber -tired backhoe. Five (5) test pits
were advanced onsite. A log of each exploration is included with this report in Appendix B. Two (2)
percolation tests were also performed on the subject site (Appendix C). Three (3) ground water
measurement standpipe piezometers were installed onsite. Field studies were completed during May
of 2017 by our field personnel who conducted field excavation location mapping, logged the
excavations, and obtained samples of representative soils for laboratory testing. The approximate
locations of the explorations are indicated on the enclosed Site Exploration Plan (Figure 2). The
Unified Soil Classification System (USCS) Classification was used to visually classify the onsite soils
during the field evaluation.
REGIONAL GEOLOGY
The subject site is situated within the western portion of the Boise River Valley, which comprises the
northwestern portion of the Snake River Plain physiographic province. The western portion of the
Snake River Plain is aligned in a northwest -southeast direction and generally divides the Owyhee
mountains to the south from the Central Idaho mountains toward the north (Wood and Clemens,
2004). The headwaters of the Boise River are located in the Central Idaho mountains east of Boise,
Idaho. The river leaves the central mountains and enters the Snake River Plain near Barber and drains
BRICKYARD JUNE 12, 2017
LAND DEVELOPMENT PARTNERS, LLC PAGE 3
PROJECT NO. 1867-11133
toward the west into the Snake River near Parma. The Owyhee mountains and the Central Idaho
Mountains are composed predominantly of volcanic and igneous rocks. The western portion of the
Snake River Plain is a northwest trending complex graben formed by extension and regional uplift
along the northern boundary of the basin and range province (Wood and Clemens, 2004). The graben
generally forms a basin which has been partially filled with younger sedimentary and volcanic rocks
(Malde, 1991).
The Boise River Valley is bounded on the northeast by the Boise Front, which is a northwest trending
topographic high extending generally from Boise to Emmett, Idaho. The Boise Front consists of
Cretaceous aged granitic and metamorphic rocks cut by Tertiary aged rhyolite and overlain with
Miocene aged lake sediments (Wood and Clemens, 2004). These units have been cut by northwest
trending faults which down drop these units toward the southwest. The faults also provide conduits
for Quaternary aged basalt intrusions and flows (Malde, 1991).
The depositional environment for the valley floor is dominantly lake laid deposits of sand, silt and clay.
These materials were deposited during two periods of lake activity, one during the Miocene and the
other during the Pleistocene. This valley infilling process has been subsequently truncated by down
faulting within the valley ranging in height from a few feet to over 50 feet. Younger alluvium has been,
and continues to be, transported dominantly by water and deposited on the basins gently sloping valley
floor and within low-level flood plains. Portions of the alluvial deposits are being down cut by
intermittent streams to the flood plain, and as a result stream terraces are being formed.
SITE SOILS
Artificial Fill
Based on our field studies, some spread fills were observed along the perimeter of the site and near
the interior roadway. This fill is generally associated with the construction of the roadway and nearby
residential developments. This spread fill shall be considered artificial fill. The majority of the property
has been cultivated for agricultural use, the upper 6 to 12 inches of material has been disturbed and
consists of a silt with sand with a moderate amount of organics and roots, this shall be considered
artificial fill. Deeper fills may be encountered onsite. The "Artificial Fills" are soft and contain
organics/roots and are not considered suitable for support of foundations. All artificial fill material
should be removed as described in the "Removals" section of this report.
Native Alluvial Soils
Alluvial soils encountered generally consisted of surficial layers of silt and lean clay underlain by sands
with varying amounts of silt content. The moisture content within the alluvial materials was generally
slightly moist to moist near surface and moist at depth. The consistency of these soils ranged from
loose to medium dense near surface and dense to very dense at depth. We anticipate that the onsite
soils can be excavated with conventional earthwork equipment. Thin partially cemented lenses of soils
were encountered in the majority of our excavations; however, we anticipate that the onsite soils can
be excavated with conventional earthwork equipment equivalent to CAT D9R dozers and CAT 235
excavators. Special excavation equipment and techniques may be necessary dependent upon if harder
materials are encountered during construction.
BRICKYARD JUNE 12, 2017
LAND DEVELOPMENT PARTNERS, LLC PAGE 4
PROJECT NO. 1867-11133
After artificial fill is removed, the upper 12 inches of the alluvium will require, at a minimum, some
removal and/or processing efforts to be considered suitable for the support of the proposed site
improvements. Locally deeper processing/removals may be necessary. Refer to the
"Recommendations Earthwork Construction" section of this report for specific site preparation
recommendations.
SURFACE & GROUND WATER
Ground water was not encountered in any of our excavations. According to the State of Idaho
Department of Water Resources Well Drillers' logs, ground water in the vicinity is approximately 15
to 20 feet below the existing ground surface. Irrigation ditches exist adjacent to the site and they
transmit water on a periodic basis. Generally, irrigation ditches and canals will locally influence ground
water during the irrigation season (i.e., May through October). If encountered, wet materials should
be spread out and air-dried or mixed with drier soils to reduce their moisture content as appropriate
for fill placement. Ground water is not anticipated to adversely affect planned development, provided
that earthwork construction methods comply with recommendations contained in this report or
those made subsequent to review of the improvement plan(s). GTI assumes that the design civil
engineer of record will evaluate the site for potential flooding and set grades such that the
improvements are adequately protected. These observations reflect conditions at the time of this
investigation and do not preclude changes in local ground water conditions in the future from natural
causes, damaged structures (lines, pipes etc.), or heavy irrigation.
TECTONIC FAULTING AND REGIONAL SEISMICITY
The site is situated in an area of active as well as potentially active tectonic faults, however no faults
were observed during our field evaluation. There are a number of faults in the regional area, which
are considered active and would have an affect on the site in the form of ground shaking, should they
be the source of an earthquake. It is reasonable to assume that structures built in this area will be
subject to at least one seismic event during their life, therefore, it is recommended that all structures
be designed and constructed in accordance with the International Building Code (IBC). Based on our
experience in the general vicinity, references in our library, field evaluation of the site, a Seismic
Design Site Class Designation of `D' may be used for seismic design.
Secondary Seismic Constraints
The following list includes other potential seismic related hazards that have been evaluated with
respect to the site, but in our opinion, the potential for these seismically related constraints to affect
the site is considered negligible.
Liquefaction
* Dynamic Settlements
* Surface Fault Rupture
* Ground Lurching or Shallow Ground Rupture
BRICKYARD JUNE 12, 2017
LAND DEVELOPMENT PARTNERS, LLC PAGE 5
PROJECT NO. 1867-1133
Summary
It is important to keep in perspective that if a seismic event were to occur on any major fault, intense
ground shaking could be induced to this general area. Potential damage to any settlement sensitive
structures would likely be greatest from the vibrations and impelling force caused by the inertia of the
-_ structures mass than that created from secondary seismic constraints. Considering the subsurface
soil conditions and local seismicity, it is estimated that the site has a low risk associated with the
potential for these phenomenon to occur and adversely affect surface improvements. These potential
risks are no greater at this site than they are for other structures and improvements developed on the
alluvial materials in this vicinity.
RESULTS OF LABORATORY TESTING
Laboratory tests were performed on representative samples of the onsite earth materials in order to
evaluate their physical and chemical characteristics. The tests performed and the results obtained are
presented in Appendix D.
CONCLUSIONS
Based on our field exploration, laboratory testing and engineering analyses, it is our opinion that the
subject site is suited for development from a geotechnical engineering viewpoint. The
recommendations presented herein should be incorporated into the final design, grading, and
construction phases of development. The engineering analyses performed concerning site preparation
and the recommendations presented below, have been completed using the information provided to
us regarding site development. In the event that the information concerning proposed development is
not correct, the conclusion and recommendations contained in this report shall not be considered
valid unless the changes are reviewed and conclusions of this report are modified or approved in
writing by this office.
RECOMMENDATIONS - EARTHWORK CONSTRUCTION
General
All grading should conform to the International Building Code (IBC) and the requirements of the City
of Meridian and/or Ada County except where specifically superseded in the text of this report.
During earthwork construction, all removals, drain systems, slopes, and the general grading
procedures of the contractor should be observed and the fill selectively tested.
Based on the classification of the site soils encountered, we recommend that site construction be
undertaken during the dry weather seasons. If grading is undertaken during the wet periods of the
year, pumping and rutting of the site soils is anticipated. If pumping and rutting conditions occur, and
loose saturated disturbed areas are created, the soils shall be removed to undisturbed soil or be
replaced/recompacted to structural fill requirements. If further soil stabilization techniques are
required during future grading activities, GTI can provide further recommendations at that time. If
unusual or unexpected conditions are exposed in the field, they should be reviewed by this office and
BRICKYARD
LAND DEVELOPMENT PARTNERS, LLC
PROJECT NO. 1867-11133
JUNE 12, 2017
PAGE 6
if warranted, modified and/or additional recommendations will be offered. It is recommended that the
earthwork contractor(s) perform their own independent reconnaissance of the site to observe field
conditions first hand. If the contractor(s) should have any questions regarding site conditions, site
preparation, or the remedial recommendations provided, they should contact an engineer at GeoTek
for any necessary clarifications prior to submitting earthwork bids. All applicable requirements of local
and national construction and general industry safety orders, the Occupational Safety and Health Act,
and the Construction Safety Act should be met.
Demolition
The following recommendations are provided as guidelines in the event a structure is encountered
that are not intended to remain.
1. All existing surface or subsurface structures (not intended to remain), within the area to be
developed, should be razed and moved off site.
2. If a septic tank (to be abandoned or below a proposed improvement) is located within the
project site, it is recommended that it be pumped out and with few exceptions likely removed.
Any leach lines, seepage pits, or other pipes associated with this structure should also be
removed or properly abandoned.
3. If any wells are encountered, an attempt should be made to identify the owner and purpose of
the well. Well abandonment should adhere to the recommendations provided by the Idaho
Department of Water Resources, the Public Health Department, or any other government
agencies. If the well is located in the area of a proposed structure, these recommendations
should be reviewed by GTI and if warranted, additional geotechnical recommendations will be
offered.
Removals/Processing - General
Presented below are removal/processing recommendations for the various soils encountered on the
project. Debris, vegetation, and other deleterious material should be stripped/removed from areas
proposed for structural improvements.
Based on a review of the exploratory logs and our site reconnaissance, after the artificial fill is
removed (upper 6 to 12 inches), a minimum removal/processing depth of 12 inches into alluvial
materials should be accomplished across the site. If the left in place soils can be scarified to encounter
a competent layer below; they may be processed in place; otherwise, they should be removed to
competent material. Locally deeper removals/processing may be necessary based on the field
conditions exposed.
Beneath the foundations, a minimum of 12 inches of compacted structural fill, meeting the
requirements of the Structural Fill and Import Soils section of this report, should be moisture
conditioned and compacted to provide a more uniform foundation support. Structural fill should
e extend a minimum of 12 inches horizontally, from the edge of the footings, for each 12 inches of
F thickness placed below the footings. A minimum relative compaction of 95 percent of the laboratory
i
maximum modified density (ASTM D 1557) at moisture content of optimum or above is necessary to
generate any near surface settlements. Locally deeper removals/processing may be necessary based on
eoTek, Inc.
BRICKYARD JUNE 12, 2017
LAND DEVELOPMENT PARTNERS, LLC PAGE 7
PROJECT NO. 1867-1133
the conditions exposed. Removal bottoms should be checked by a representative of GeoTek, Inc. to
see if deeper removals are necessary.
If very hard cemented materials are encountered during over -excavation, excavation may potentially
be terminated, but this will need to be determined on a case by case basis by a representative of GTI.
Foundations for the proposed structures may be founded on cemented material; however, in order to
avoid the potential for differential settlement, the entire foundation would need to be supported
entirely on the cemented material. If this is not possible, cemented materials should be removed to a
minimum depth of 12 inches below the bottom of the footing and replaced with compacted structural
fill. This can best be determined in the field based upon the conditions exposed. Termination of any
excavation on cemented soils will need to be reviewed by GTI and the owner.
If existing improvements or property line restrictions limit removals, condition specific
recommendations would be provided on a case-by-case basis. During earthwork construction, care
should be taken by the contractor so that adverse ground movements or settlements are not
generated affecting existing improvements.
Transitional Pads
Transitional pads are defined in this report as pads which are partially cut and partially fill. To mitigate
some of the differential settlement which will occur on transitional pads, the cut side should be over-
excavated/processed to a minimum depth equal to 2 feet below the bottom of the footings or to the
depth of the fill, which ever is less. On transitional pads with more than 7.5 feet of fill, plans need to
be reviewed by GTI and site-specific recommendations will be provided.
Excavation Difficulty
We anticipate that the onsite soils can be excavated with conventional earthwork. Seasonal
conditions could cause wet soil conditions to occur onsite. Depending on the depth of cuts, it should
be expected that special excavation and fill placement measures may be necessary. Wet materials
should be spread out and air-dried or mixed with drier soils to reduce their moisture content to the
appropriate level for fill placement. Frozen soils, if encountered, should be removed and allowed to
thaw prior to any fill placement or construction. Removal bottoms should be checked by a
representative of GTI to see if deeper removals are necessary.
j Fill Placement
Subsequent to completing removals/processing and ground preparation, the excavated onsite and/or
imported soils may be placed in relatively thin lifts (less than 8 inches thick), cleaned of vegetation and
debris, brought to at least optimum moisture content, and compacted to a minimum relative
compaction of 95 percent of the laboratory standard (ASTM D 1557).
Structural Fill and Import Soils
Potentially, soils will be imported to the site for earthwork construction purposes. A sample of any
intended import material should first be submitted to GTI so that, if necessary, additional laboratory
or chemical testing can be performed to verify that the intended import material is compatible with
onsite soils. In general, structural fill and import soils should be within the following minimum
guidelines:
BRICKYARD JUNE 12, 2017
LAND DEVELOPMENT PARTNERS, LLC PAGE 8
PROJECT NO. 1867-ID3
Free of organic matter and debris.
Maintain less than 0.2 percent sulfate content.
Maintain less than 3.0 percent soluble material.
Maintain less than 0.02 percent soluble chlorides.
Maintain less than 0.2 percent sodium sulfate content.
Maintain a Plasticity Index less than 12 (i.e., low expansive).
One hundred percent passing the six-inch screen.
* At least seventy-five percent passing a three-inch screen.
Observation and Testing
During earthwork construction all removal/processing and the general grading procedures should be
observed and the fill selectively tested by a representative(s) of GTI. If unusual or unexpected
conditions are exposed in the field, they should be reviewed by GTI and if warranted, modified and/or
additional recommendations will be offered.
Ground Water
Ground water was not encountered during our field evaluation. According to the State of Idaho
Department of Water Resources Well Drillers' logs, groundwater in the vicinity is approximately 15
to 20 feet below the existing ground surface. Based on site conditions in the future, a transient high
ground water condition could develop over a clay or less permeable layer and this condition could
generate down gradient seepage. The possible effect these layers could have on this and adjacent sites
should be considered, and can best be evaluated in the field during grading. If warranted by exposed
field conditions, it may be recommended that a drainage system be established to collect and convey
any subsurface water to an appropriate location for drainage. Typically, potential areas of seepage are
difficult to identify prior to their occurrence; therefore, it is often best to adopt a "wait and see"
approach to determine if any seepage conditions do develop, at which time specific recommendation
to mitigate an identified condition can be provided.
Earthwork Settlements
Ground settlement should be anticipated due to primary consolidation and secondary compression.
The total amount of settlement and time over which it occurs is dependent upon various factors,
including material type, depth of fill, depth of removals, initial and final moisture content, and in-place
density of subsurface materials. Compacted fills, to the heights anticipated, are not generally prone to
excessive settlement. However, some settlement of the native alluvium is expected and the majority
of this settlement is anticipated to occur during grading.
Slope Stability
No significantly high (greater than ten feet) slopes are anticipated to be constructed onsite. All slopes
should be designed at gradients of 2 to I (Horizontal to Vertical) or flatter. All slopes should be
constructed in accordance with the minimum requirements of the City of Meridian and/or Ada
County and the International Building Code. Cut and fill slopes are anticipated to perform adequately
in the future with respect to gross and surficial stability if the soil materials are maintained in a solid to
semi-solid state (as defined by the soils Atterberg Limits) and are limited to the heights prescribed
herein.
BRICKYARD JUNE 12, 2017
LAND DEVELOPMENT PARTNERS, LLC PAGE 9
PROJECT NO. 1867-1133
The importance of proper compaction to the face of a slope cannot be overemphasized. In order to
achieve proper compaction, one or more of the three following methods should be employed by the
contractor following implementation of typical slope construction guidelines: 1) track walk the slopes
at grade, 2) use a combination of sheeps foot roller and track walking, or 3) overfill the slope 3 to 5
feet laterally and cut it back to grade.
Random testing will be performed to verify compaction to the face of the slope. If the tests do not
meet the minimum recommendation of 90 percent relative compaction, the contractor will be
informed and additional compactive efforts recommended. A final evaluation of cut slopes during
grading will be necessary in order to identify any areas of adverse conditions. The need for remedial
stabilization measures should be based on observations made during grading by a representative of this
office. Based on our observations, and if warranted, specific remedial recommendations will be
offered for stabilization.
RECOMMENDATIONS — FOUNDATIONS
General
Foundation design and construction recommendations are based on preliminary laboratory testing and
engineering analysis performed on near surface soils. The proposed foundation systems should be
designed and constructed in accordance with the guidelines contained herein and in the International
Building Code.
Based on our experience in the area, the soils onsite should have a negligible corrosive potential to
concrete and metal, materials selected for construction purposes should be resistant to corrosion.
Where permitted by building code, PVC pipe should be utilized. All concrete should be designed,
mixed, placed, finished, and cured in accordance with the guidelines presented by the Portland
Cement Association (PCA) and the American Concrete Institute (ACI).
Based on our grading recommendations, the soils beneath the foundations are anticipated to have low
expansion potential. Therefore, foundation recommendations for low expansive soil conditions are
provided below. If more expansive soils are encountered, the pad(s) will either need to be regraded
and the more expansive soils removed by the contractor or increased foundation recommendations
will need to be provided.
Conventional Foundation Recommendations
Column loads are anticipated to be 50 kips or less while wall loads are expected to be 3 kips per lineal
foot or less. The conventional recommendations provided are from a geotechnical engineering
perspective (i.e., for expansive conditions) and are not meant to supersede the design by the project's
structural engineer.
Preliminary recommendations for foundation design and construction are presented below. The
specific criteria to be used should be verified on evaluation of the proposed buildings, structural loads,
and expansion and chemical testing performed after grading is complete.
BRICKYARD JUNE 12, 2017
LAND DEVELOPMENT PARTNERS, LLC PAGE 10
PROJECT NO. 1867-1133
The bearing values indicated are for the total dead plus frequently applied live loads and may be
increased by one third for short duration loading which includes the effects of wind or seismic forces.
When combining passive pressure and friction for lateral resistance, the passive component should be
reduced by one third. A grade beam, reinforced as below and at least 12 inches wide, should be
utilized across all large entrances. The base of the grade beam should be at the same elevation as the
bottom of the adjacent footings. Footings should be founded at a minimum depth of 24 inches below
lowest adjacent ground surface as required by local codes to extend below the frost line.
Reinforcement for spread footings should be designed by the project's structural engineer.
For foundations systems including a crawl space, it is recommended that it be designed so that water
is not allowed to penetrate the crawl space. Proper grading and backfill for the foundations is critical
and should adhere to the "fill placement" and "drainage" recommendations of this evaluation as well as
local building codes.
The coefficient of friction and passive earth pressure values recommended are working values. Strip
footings should have a minimum width of one foot and spread footings should have a minimum soil to
concrete area of four square feet. Increases are allowed for the bearing capacity of the footings at a
rate of 250 pounds per square foot for each additional foot of width and 250 pounds per square foot
for each additional foot of depth into the recommended bearing material, up to a maximum outlined.
If the bearing value exceeds 3,000 psf, an additional review by GTI is recommended. As mentioned
earlier, the structural fill should be moisture conditioned and compacted a minimum of 12 inches
below bottom of footings. Prior to the placement of concrete, moisture should be added to the
subgrade soils to minimize water loss of the concrete during placement and curing.
If the grading recommendations presented in this report are complied with, proposed concrete floor
slabs may be supported on a 6 -inch layer of compacted 3/4 -inch aggregate base material. A structural
engineer should evaluate the proposed loading and determine the slab thickness, concrete strength,
and the locations and size of the reinforcing steel.
Modulus of subgrade reaction (k) may be used in the design of the floor slab supporting heavy truck
traffic, forklifts, machine foundations, and heavy storage areas. Based on typical R -value test results
and the interrelationships published by the Portland Cement Association for "R" -Value (resistance
value) vs Modulus of Subgrade Reaction, an approximate k -value (modulus of subgrade reaction) of
125 pounds per square inch per inch may be utilized for slab design.
Minimum
Structural Fill
Minimum
Allowable
Passive
Maximum
Footing
Depth Below
Footing
Bearing
Coefficient
Earth
Earth
Type
Footing
Depth
Pressure
of Friction
Pressure
Pressure
Bottom
(inches)
(psf)
(psf/ft)
(psf)
inches
Strip or
12
24
1,500
0.35
250
3,000
Spread
The coefficient of friction and passive earth pressure values recommended are working values. Strip
footings should have a minimum width of one foot and spread footings should have a minimum soil to
concrete area of four square feet. Increases are allowed for the bearing capacity of the footings at a
rate of 250 pounds per square foot for each additional foot of width and 250 pounds per square foot
for each additional foot of depth into the recommended bearing material, up to a maximum outlined.
If the bearing value exceeds 3,000 psf, an additional review by GTI is recommended. As mentioned
earlier, the structural fill should be moisture conditioned and compacted a minimum of 12 inches
below bottom of footings. Prior to the placement of concrete, moisture should be added to the
subgrade soils to minimize water loss of the concrete during placement and curing.
If the grading recommendations presented in this report are complied with, proposed concrete floor
slabs may be supported on a 6 -inch layer of compacted 3/4 -inch aggregate base material. A structural
engineer should evaluate the proposed loading and determine the slab thickness, concrete strength,
and the locations and size of the reinforcing steel.
Modulus of subgrade reaction (k) may be used in the design of the floor slab supporting heavy truck
traffic, forklifts, machine foundations, and heavy storage areas. Based on typical R -value test results
and the interrelationships published by the Portland Cement Association for "R" -Value (resistance
value) vs Modulus of Subgrade Reaction, an approximate k -value (modulus of subgrade reaction) of
125 pounds per square inch per inch may be utilized for slab design.
BRICKYARD JUNE 12, 2017
LAND DEVELOPMENT PARTNERS, LLC PAGE I 1
PROJECT NO. 1867-ID3
It is recommended that a plastic water vapor retarder be utilized below the slab. The vapor retarder
should conform to the specifications presented in ASTM E 1745-97 and should be placed as described
in ASTM E 1643-98 and the Guide for Concrete Floor and Slab Construction, published by the
American Concrete Institute (ACI 302.1 R-96).
A minimum ten -mil thick vapor retarder should be placed on a minimum 6 -inch thick layer of
aggregate base material and a 2 -inch layer of select sand should be placed over the vapor retarder.
The vapor retarder should be lapped adequately to provide a continuous protection under the entire
slab.
Foundation Settlement
Provided that the recommendations contained in this report are incorporated into final design and
construction phase of development, total settlement is estimated to be less than one inch and
differential settlement is estimated to be less than 0.75 inches for a 25 -foot span. Two-way angular
distortions due to settlements are not estimated to exceed 1/400. The structures should be loaded
uniformly so as to avoid any localized settlements.
PAVEMENT SECTIONS
Pavement sections presented in the following table are based on an R -value of 24, assumed traffic
index(s) for development and estimated traffic index(s) for development. These pavement sections
are presented for planning purposes only and should be verified based on specific laboratory testing
performed subsequent to rough grading of the site.
Pavement Construction and Maintenance
All section changes should be properly transitioned. If adverse conditions are encountered during the
preparation of subgrade materials, special construction methods may need to be employed. All
subgrade materials should be processed to a minimum depth of 12 inches and compacted to a
minimum relative compaction of 90 percent near optimum moisture content. All aggregate base
should be compacted to a minimum relative compaction of 95 percent at optimum moisture content.
The recommended pavement sections provided are meant as minimums. If thinner or highly variable
pavement sections are constructed, increased maintenance and repair should be expected. If the ADT
(average daily traffic) or ADTT (average daily truck traffic) increases beyond that intended, as reflected
by the traffic index(s) used for design, increased maintenance and repair could be required for the
pavement section.
Positive site drainage should be maintained at all times. Water should not be allowed to pond or seep
into the ground. If planters or landscaping are adjacent to paved areas, measures should be taken to
minimize the potential for water to enter the pavement section.
BRICKYARD JUNE 12, 2017
LAND DEVELOPMENT PARTNERS, LLC PAGE 12
PROJECT NO. 1867-11133
Hot -Mix Asphalt Pavement Sections
*Subbase gradation specification requirement per the current edition of the Idaho State Public Works
Construction (ISPWC) Manual.
Concrete Pavement Section
The Portland Cement Concrete (PCC) pavement sections presented below are based on an R -value of
24, assumed traffic index(s), a load safety factor of 1. 1, a modulus of rupture of 600 psi, and the
guidelines presented in the latest revision to the Portland Cement Association, "Portland Cement
Concrete Pavement Design for Light, Medium & Heavy Traffic (1991)". These preliminary pavement
sections are presented for planning purposes only and should be verified based on specific laboratory
testing performed subsequent to rough grading of the site.
The following criteria for the Portland Cement Concrete pavement should also be incorporated into
preliminary site design. No traffic should be allowed upon the newly poured concrete slabs for a
minimum of 7 days after pouring. This time period is critical as it gives the concrete time to cure and
gain strength. Perimeter edges of the concrete should be thickened, as appropriate. Longitudinal and
transverse joints should be utilized to control cracking. Longitudinal and transverse control joints
should be placed on approximately I I to 15 foot centers. These control joints can be constructed by
using expansion joint material and pouring each section separately or by saw cutting the slabs to a
minimum depth of one-fourth the slab thickness. Other methods for appropriately providing control
joints may also be utilized. All joints should be properly sealed. All concrete should be designed,
mixed, placed, finished, and cured in accordance with the guidelines presented by the Portland
Cement Association (PCA), the American Concrete Institute (ACI) and the International Building
Code (I BC).
MINIMUM
MINIMUM AGGREGATE
ASPHALT
THICKNESS (in.)
ASSUMED TRAFFIC
SUBGRADE
CONCRETE
Aggregate
Subbase*
RIGHT -OF -AWAY
R -VALUE
THICKNESS
Base (3/4"
(Uncrushed
(in.)
minus)
Aggregate)
Parking and Drives
No Truck Access
24
2.5
4.0
10.0
TI = 6.0
Truck Access
24
3.0
6.0
12.0
TI = 8.0
Heavy Truck Access
24
4.0
8.0
14.0
TI = 10.0
*Subbase gradation specification requirement per the current edition of the Idaho State Public Works
Construction (ISPWC) Manual.
Concrete Pavement Section
The Portland Cement Concrete (PCC) pavement sections presented below are based on an R -value of
24, assumed traffic index(s), a load safety factor of 1. 1, a modulus of rupture of 600 psi, and the
guidelines presented in the latest revision to the Portland Cement Association, "Portland Cement
Concrete Pavement Design for Light, Medium & Heavy Traffic (1991)". These preliminary pavement
sections are presented for planning purposes only and should be verified based on specific laboratory
testing performed subsequent to rough grading of the site.
The following criteria for the Portland Cement Concrete pavement should also be incorporated into
preliminary site design. No traffic should be allowed upon the newly poured concrete slabs for a
minimum of 7 days after pouring. This time period is critical as it gives the concrete time to cure and
gain strength. Perimeter edges of the concrete should be thickened, as appropriate. Longitudinal and
transverse joints should be utilized to control cracking. Longitudinal and transverse control joints
should be placed on approximately I I to 15 foot centers. These control joints can be constructed by
using expansion joint material and pouring each section separately or by saw cutting the slabs to a
minimum depth of one-fourth the slab thickness. Other methods for appropriately providing control
joints may also be utilized. All joints should be properly sealed. All concrete should be designed,
mixed, placed, finished, and cured in accordance with the guidelines presented by the Portland
Cement Association (PCA), the American Concrete Institute (ACI) and the International Building
Code (I BC).
BRICKYARD JUNE 12, 2017
LAND DEVELOPMENT PARTNERS, LLC PAGE 13
PROJECT NO. 1867-11133
*Subbase gradation specification requirement per the current edition of the Idaho State Public Works
Construction (ISPWC) Manual.
OTHER RECOMMENDATIONS
Site Improvements
As is commonly known, expansive soils are problematic with respect to the design, construction and
long term performance of concrete flatwork. Due to the nature of concrete flatwork, it is essentially
impossible to totally mitigate the effects of soil expansion. Typical measures to control soil expansion
for structures include; low expansive soil caps, deepened foundation system, increased structural
design, and soil presaturation. As they are generally not cost effective, these measures are very
seldom utilized for flatwork because it's less costly to simply replace any damaged or distressed
sections than to "structurally" design them.
Even if "structural" design parameters are applied to flatwork construction, there would still be
relative movements between adjoining types of structures and other improvements (e.g., curb and
sidewalk). This is particularly true as the level of care during construction of flatwork is often not as
meticulous as that for structures. Unfortunately, it is fairly common practice for flatwork to be
poured on subgrade soils, which have been allowed to dry out since site grading. Generally after
flatwork construction is completed, landscape irrigation begins, utility lines are pressurized, and
drainage systems are utilized; presenting the potential for water to enter the dry subgrade soils,
causing the soil to expand.
Recommendations for exterior concrete flatwork design and construction can be provided upon
request. If, in the future, any additional improvements are planned for the site, recommendations
concerning the geological or geotechnical aspects of design and construction of said improvements
could be provided upon request. This office should be notified in advance of any fill placement,
grading, or trench backfilling after rough grading has been completed. This includes any grading, utility
trench and retaining wall backfills.
eoTek, Inc.
MINIMUM AGGREGATE
MINIMUM
THICKNESS (in.)
ASSUMED TRAFFIC
SUBGRADE
CONCRETE
Aggregate
Subbase*
RIGHT -OF -AWAY
R -VALUE
THICKNESS
Base (3/4"
(Uncrushed
(in.)
minus)
Aggregate)
Parking and Drives
No Truck Access
24
7.0
6.0
11.0
TI = 6.0
Truck Access
24
8.0
6.0
10.0
TI = 8.0
Heavy Truck Access
24
9.0
6.0
9.0
TI = 10.0
*Subbase gradation specification requirement per the current edition of the Idaho State Public Works
Construction (ISPWC) Manual.
OTHER RECOMMENDATIONS
Site Improvements
As is commonly known, expansive soils are problematic with respect to the design, construction and
long term performance of concrete flatwork. Due to the nature of concrete flatwork, it is essentially
impossible to totally mitigate the effects of soil expansion. Typical measures to control soil expansion
for structures include; low expansive soil caps, deepened foundation system, increased structural
design, and soil presaturation. As they are generally not cost effective, these measures are very
seldom utilized for flatwork because it's less costly to simply replace any damaged or distressed
sections than to "structurally" design them.
Even if "structural" design parameters are applied to flatwork construction, there would still be
relative movements between adjoining types of structures and other improvements (e.g., curb and
sidewalk). This is particularly true as the level of care during construction of flatwork is often not as
meticulous as that for structures. Unfortunately, it is fairly common practice for flatwork to be
poured on subgrade soils, which have been allowed to dry out since site grading. Generally after
flatwork construction is completed, landscape irrigation begins, utility lines are pressurized, and
drainage systems are utilized; presenting the potential for water to enter the dry subgrade soils,
causing the soil to expand.
Recommendations for exterior concrete flatwork design and construction can be provided upon
request. If, in the future, any additional improvements are planned for the site, recommendations
concerning the geological or geotechnical aspects of design and construction of said improvements
could be provided upon request. This office should be notified in advance of any fill placement,
grading, or trench backfilling after rough grading has been completed. This includes any grading, utility
trench and retaining wall backfills.
eoTek, Inc.
BRICKYARD
LAND DEVELOPMENT PARTNERS, LLC
PROJECT NO. 1867-ID3
JUNE 12, 2017
PAGE 14
Landscape Maintenance and Planting
Water has been shown to weaken the inherent strength of all earth materials. Slope stability is
significantly reduced by overly wet conditions. Graded slopes constructed within and utilizing onsite
materials would be erosive. Eroded debris may be minimized and surfiicial slope stability enhanced by
establishing and maintaining a suitable vegetation cover as soon as possible after construction.
Compaction to the face of fill slopes would tend to minimize short-term erosion until vegetation is
established. Plants selected for landscaping should be lightweight, deep-rooted types, which require
little water and are capable of surviving the prevailing climate. From a geotechnical standpoint leaching
is not recommended for establishing landscaping. If the surface soils are processed for the purpose of
adding amendments, they should be recompacted to 90 percent compaction.
Only the amount of irrigation necessary to sustain plant life should be provided. Over watering the
landscape areas could adversely affect proposed site improvements. We recommend that any
proposed open bottom planter areas adjacent to proposed structures, be eliminated for a minimum
distance of 5 feet and desert landscape using xeriscape technology be used outside of this buffer zone.
As an alternative, closed bottom type planters could be utilized. An outlet, placed in the bottom of
the planter, could be installed to direct drainage away from structures or any exterior concrete
flatwork. Irrigation timers should be adjusted on a monthly basis.
Soil Corrosion
Based on our experience in the area, the soils onsite should have a negligible corrosive potential to
concrete and metal, materials selected for construction purposes should be resistant to corrosion.
Where permitted by building code PVC pipe should be utilized. All concrete should be designed,
mixed, placed, finished, and cured in accordance with the guidelines presented by the Portland
Cement Association (PCA) and the American Concrete Institute (ACI).
Trench Excavation
All footing trench excavations should be observed by a representative of this office prior to placing
reinforcement. Footing trench spoil and any excess soils generated from utility trench excavations
should be compacted to a minimum relative compaction of 90 percent if not removed from the site.
Considering the nature of the onsite soils, it should be anticipated that caving or sloughing could be a
factor in excavations. Shoring or excavating the trench walls and slopes to the angle of repose
(typically 25 to 45 degrees) may be necessary and should be anticipated in non-cemented soils. All
excavations should be observed by one of our representatives and conform to national and local safety
codes.
Onsite Utility Trench Backfill
Considering the overall nature of the soil encountered onsite, it should be anticipated that materials
will need to be imported to the site for use as pipe bedding and pipe zone material. All utility trench
f backfill should be brought to near optimum moisture content and then compacted to obtain a
minimum relative compaction of 90 percent of the laboratory standard. Compaction testing and
observation, along with probing should be performed to verify the desired results. Sand backfill, unless
excavated from the trench, should not be used adjacent to perimeter footings or in trenches on
slopes. Compaction testing and observation, along with probing should be performed to verify the
desired results. Sand backfill, unless excavated from the trench, should not be used adjacent to
perimeter footings or in trenches on slopes. Compaction testing and observation, along with probing
eoTek, Inc.
BRICKYARD JUNE 12, 2017
LAND DEVELOPMENT PARTNERS, LLC PAGE 15
PROJECT NO. 1867-11133
should be performed to verify the desired results. Offsite utility trenches should be compacted to a
minimum of 90 relative compaction. Compaction testing and observation, along with probing should
be performed to verify the desired results.
Drainage
Positive site drainage should be maintained at all times in accordance with the IBC. Drainage should
not flow uncontrolled down any descending slope. Water should be directed away from foundations
and not allowed to pond and/or seep into the ground. Pad drainage should be directed toward the
street or other approved area. The ground immediately adjacent to the foundation shall be sloped
away from the building at a minimum of 5 -percent for a minimum distance of 10 feet measured
perpendicularly to the face of the wall. If physical obstructions prohibit 10 feet of horizontal distance,
a 5 -percent slope shall be provided to an approved alternate method of diverting water away from the
foundation. Swales used for this purpose shall be sloped a minimum of 2 -percent where located
within 10 feet of the building foundation. Impervious surfaces within 10 feet of the building foundation
shall be sloped a minimum of 2 -percent away from the building. Roof gutters and down spouts should
be utilized to control roof drainage. Down spouts should outlet onto paved areas or a minimum of
five feet from proposed structures or into a subsurface drainage system. Areas of seepage may
develop due to irrigation or heavy rainfall. Minimizing irrigation will lessen this potential. If areas of
seepage develop, recommendations for minimizing this effect could be provided upon request.
PLAN REVIEW
Final grading, foundation, and improvement plans should be submitted to this office for review and
comment as they become available, to minimize any misunderstandings between the plans and
recommendations presented herein. In addition, foundation excavations and earthwork construction
performed on the site should be observed and tested by this office. If conditions are found to differ
substantially from those stated, appropriate recommendations would be offered at that time.
LIMITATIONS
The materials encountered on the project site and utilized in our laboratory study are believed
representative of the area; however, soil materials vary in character between excavations and
conditions exposed during mass grading. Site conditions may vary due to seasonal changes or other
factors. GeoTek, Inc. assumes no responsibility or liability for work, testing, or recommendations
performed or provided by others. Since our study is based upon the site materials observed, selective
laboratory testing and engineering analysis, the conclusions and recommendations are professional
opinions. These opinions have been derived in accordance with current standards of practice and no
warranty is expressed or implied. Standards of practice are subject to change with time.
RfAaHMMIM
BRICKYARD
LAND DEVELOPMENT PARTNERS, LLC
PROJECT NO. 1867-ID3
JUNE 12, 2017
PAGE 16
The opportunity to be of service is greatly appreciated. If you have any questions concerning this
report or if we may be of further assistance, please do not hesitate to contact the undersigned.
Respectfully submitted,
GeoTek, Inc.
Tyler Lydeen, EI
Staff Professional
GeoTek, Inc.
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FIGURE I
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Meridian, Idaho
G E O T E K Prepared for: TO Engineers, Inc.
GEOTECHNICAL I ENVIRONMENTAL I MATERIALS
Project No.: Report Date: Drawn By:
320 E. Corporate Dr, Suite 300, Meridian, ID 83642 1867-ID3 June 2017 TL
(208) 888-7010 (phone) / (208) 888-7924 (FAX)
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REFERENCES
Ada County Highway District Development Policy Manual, Revised by Resolution No. 690, October
2003
ASTM, 200, "Soil and Rock: American Society for Testing and Materials," vol. 4.08 for ASTM test
methods D-420 to D-4914, 153 standards, 1,026 pages; and vol. 4.09 for ASTM test method D-
4943 to highest number.
Breckinridge, R.M., Lewis, R.S., Adema, G.W., Weisz, D.W., 2003, Map of Miocene and Younger Faults
in Idaho, Idaho Geological Survey, University of Idaho
Day, Robert W., 1999, Geotechnical and Foundation Engineering — Design and Construction
Day, Robert W., 2002, Geotechnical Earthquake Engineering Handbook
GeoTek, Inc., In-house proprietary information.
Idaho Department of Water Resources, Treasure Valley Hydrology — Geology
Idaho Department of Water Resources, Well Information, Well Driller Reports, 2015
Idaho Transportation Department CD-ROM Publications
Johnson, Bruce R. and Raines, Gary L., 1995, Digital representation of the Idaho state geologic map: a
contribution to the Interior Columbia Basin Ecosystem Management Project. USGS Open -File
Report 95-690
Malde, H.E., 1991. Quaternary geology and structural history of the Snake River Plain, Idaho and
Oregon. In: The Geology of North America, Quaternary Nonglacial Geology: Conterminous
U.S., Vol. K-2, 252-281 pp.
Othberg, K.L., 1994. Geology and geomorphology of the Boise Valley and adjoining areas, western
Snake River Plain, Idaho. Idaho Geological Survey Bulletin 29: 54 pp.
USGS, 2003, Seismic Hazard Map of Idaho, Peak Acceleration (%g) with 2% Probability of Exceedance
in 50 years.
lm��
TEST PIT LOG GENERAL NOTES
CONSISTENCY OF FINE-GRAINED SOILS
GRAIN SIZE TERMINOLOGY
RELATIVE DENSITY OF COARSE-GRAINED SOILS
Unconfined
Compressive
Strength, Qu
psf
Standard
Penetration or
N -value (SS)
Blows/Ft. Consistency
Particle Size
Standard Penetration (SPT)
or N -value (SS) Relative Density
Blows/Ft.
< 500
<2 Very Soft
Over 12 in. 300mm
0-3 Ve Loose
500-1,000
2-3 Soft
12 in. to 3 in. 300mm to 75 mm
4-9 Loose
1,001 — 2,000
4-6 Firm
3 in. to #4 sieve 75mm to 4.75 mm
10-29 Medium Dense
2,001 — 4,000
7-12 Medium Stiff
#4 to #200 sieve (4.75mm to 0.075mm)
Passing 4200 Sieve (0.075mm)
30-49 Dense
2,001 — 4,000
13-26 Stiff (Hard)*
50+ Very Dense
8,000+
27+ Very Stiff(Very Hard)*
SPT penetration test using 140 pound hammer, with 30 inch free fall on 2 inch outside diameter 1% I.D. sampler.
For Ring Sampler using 140 pound hammer, with 30 inch free fall on 3 inch outside diameter2'/2 I.D. sampler, N -value X 0.7.
For fine grained soil Consistency, thumb
penetration also used per ASTM D 2488.
*The terms Stiff and Very Stiff are used in -lieu of Hard and Very Hard to avoid confusion with cemented soils.
RELATIVE PROPORTIONS OF SAND AND GRAVEL
GRAIN SIZE TERMINOLOGY
Descriptive Term(s) of other
constituents
Percent of
Dry Weight
Major Component
of Sample
Particle Size
Trace
< 15
Boulders
Over 12 in. 300mm
With
15-29
Cobbles
12 in. to 3 in. 300mm to 75 mm
Modifier
> 30
Gravel
3 in. to #4 sieve 75mm to 4.75 mm
Sand
Silt or Clay
#4 to #200 sieve (4.75mm to 0.075mm)
Passing 4200 Sieve (0.075mm)
RELATIVE HARDNESS OF CEMENTED SOILS (CALICHE)
Description
General Characteristics
Very Dense to Moderately Hard
Partially Cemented Granular Soil - Can be carved with a knife and broken with force by hand.
Very Stiff to Moderately Hard
Partially Cemented Fine -Grained Soil - Can be carved with a knife and broken with force by hand.
Moderately Hard
Moderate hammer blow required to break sample.
Hard
Heavy hammer blow required to break sample.
Very Hard
Repeated heavy hammer blows required to break sample.
UNIFIED SOIL CLASSIFICATION SYSTEM
ASTM
D 2487
Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests"
Soil Classification
Group
Symbol
Group Namea
Gravels Clean Gravels
Cu >_ 4 and 1 < Cc < 3c GW
Well -graded gravelD
More than 50% of coarse Less than 5% fines'
Cu < 4 and/or 1 > Cc > 3c GP
Poorly graded gravel',
fraction retained on
No. 4 sieve Gravels with Fines
Fines classify as ML or MH GM
Silty gravelD•F.13
Coarse -Grained Soils More than 12% fines
Fines classify as CL or CH GC
Clayey gravelo,F,G
More than 50% retained Sands Clean Sands
Cu >_ 6 and 1 < Cc < 3° SW
Well -graded sand"
on No. 200 sieve 50% or more of coarse Less than 5% fines'Cu
< 6 and/or 1 > Cc > 3c SP
Poorly graded sand"
fraction passes
No. 4 sieve Sands with Fines
Fines classify as ML or MH SM
Silty sand F,1.11
More than 12% fines'
Fines Classify as CL or CH SC
Clayey sandF,c.H
Silts and Clays inorganic
PI > 7 and plots on or above "A" line' CL
Lean clay"L•'.'
Liquid limit less than 50
PI < 4 or plots below "A" line' ML
SiltKL,"'
organic
(Liquid limit - oven dried)/(Liquid limit -not
Organic clay"' -"'H
Fine -Grained Soils
dried) < 0.75 OL
Organic silt"' -110
50% or more passes Silts and Clays inorganic
PI plots on or above "A" line CH
Fat clay"L,'•'
No. 200 sieve Liquid limit 50 or more
PI lots below "A" line MH
Elastic SiltK,L,1.1
organic
(Liquid limit - oven dried)/(Liquid limit -
Organic clayK�L M,P
not dried) < 0.75 OH
Organic siltK.L,"'D
Highly organic soils Primarily organic matter, dark in color, and organic odor PT
Peat
Sands with 5 to 12% fines require dual symbols:
^Based on the material passing the 3 -in. (75 -mm) sieve
SW -SM well -graded sand with silt,
B If field sample contained cobbles or boulders, or both, add "with cobbles
SW -SC well -graded sand with clay,
or boulders, or both" to group name.
cCu = D60/Djo Cc = (D30) /(Dio x D60)
SP -SM poorly graded sand with silt,
D If soil contains >_ 15% sand, add "with sand" to group name.
SP -SC poorly graded sand with clay
EGravels with 5 to 12% fines require dual symbols:
J If Atterberg limits plot in shaded area, soil
is a CL -ML, silty clay.
KIf soil contains 15 to 29% plus No. 200, add
"with sand" or "with
GW -GM well -graded gravel with silt,
gravel," whichever is predominant.
GW -GC well -graded gravel with clay,
L If soil contains >_ 30% plus No. 200 predominantly sand, add
GP -GM poorly graded gravel with silt,
"sandy" to group name.
GP -GC poorly graded gravel with clay.
rn If soil contains >_ 30% plus No. 200, predominantly
gravel, add
F If fines classify as CL -ML, use dual symbol GC -GM, or SC -SM.
"gravelly" to group name.
G If fines are organic, add "with organic fines" to group name.
N PI >_ 4 and plots on or above "A" line.
H If soil contains >_ 15% gravel, add "with gravel" to group name.
o PI < 4 or plots below "A" line.
P PI plots on or above "A" line.
Q PI plots below "A" line.
60XC
For classification of fine-grainedsoils
and fine-grained fractionof
coarse-grained soils50
Equation of -A" - tinedHorizontal
at PI=4 to LL=25 5.
then PI=0.73 (LL-20)tX
40 p+, Equation of "U" - line
Z Vertical at LL=16 to PI=7,
30 1 then PI=0.9 (LL -8)
U
�o
20 G
MH or OH
10 r
Lm_-
7
4 L_ L - ML ML or OL
0 ' - -. i 1
0 10 16 20 30 40 50 60 70 so 90 100 11C
LIQUID LIMIT (LL)
LOG LEGEND
SAMPLING
MATERIAL DESCRIPTION
Soil Pattern
USCS Symbol
USCS Classification
NR
FILL
Artificial Fill
Soft
GP or GW
Poorly/Well graded GRAVEL
L
GM
Silty GRAVEL
Firm
GC
Clayey GRAVEL
MD
GP -GM or GW -GM
Poorly/Well graded GRAVEL with Silt
Stiff
GP -GC or GW -GC
Poorly/Well graded GRAVEL with Clay
D
SP or SW
Poorly/Well graded SAND
Very Stiff
SM
Silty SAND
- -_ _ H =
SC
Clayey SAND
_
SP -SM or SW -SM
Poorly/Well graded SAND with Silt
SP -SC or SW -SC
Poorly/Well graded SAND with Clay
i # +
SC -SM
Silty Clayey SAND
ML
SILT
MH
Elastic SILT
CL -ML
Silty CLAY
CL
Lean CLAY
CH
Fat CLAY
PCEM
PARTIALLY CEMENTED
CEM
CEMENTED
BDR
BEDROCK
SAMPLING
Cohesionless
Soils
SPT
Ring Sample
No Recovery
Bulk Sample
Water Table
Cementation
NR
Very Loose
So
CONSISTENCY
Cohesionless
Soils
Cohesive Soils
Cementation
VL
Very Loose
So
Soft
MH
Moderately Hard
L
Loose
F
Firm
H
Hard
MD
Medium Dense
S
Stiff
VH
Very Hard
D
Dense
VS
Very Stiff
VD
Very Dense
TEST PIT L 0 G
320
LOGGED BY: LJL
PROJECT #: 1867-01 METHOD: Backhoe
APIC.",
PROJECT: Brickyard EXCAVATOR: Just Dig It
CLIENT: T -O Engineers, Inc DATE: 5/23/17
G E 0 T E K LOCATION: —43.63853[;-116.35760 ELEVATION: 2621 Feet
SAMPLES
CQ
o
T
T
C
g
O
N
TEST PIT NUMBER: TP -1
U
C
ti
REMARKS
C_
E
O
U
-
O
p
<n
m
h
v
MATERIAL DESCRIPTION AND COMMENTS
ML
Brown SILT with Sand; Slightly Moist
So
Grass vegetative ground cover
with organics present to—1'-0".
1
I
F
2
3 -XII
;i
S
4
PCEM
Tan Partially Cemented SAND; Slightly Moist
MH
6
SM
Tan Silty SAND; Slightly Moist
VD
"Hard Pan"
Percolation rate test P-1
7
Installed @ 60"
8
GP
Lt Tan Poorly Graded GRAVEL with Silt & Sand and trace
VD
"Pit Run"
3" minus Cobbles; Slightly Moist
9
10-
11
12
Bottom of Test Pit @ 12'-0"
No Ground Water Encounterd
13
14-
4151617181920
15-
16-
17-
18-
19-
20-
320 E. Corporate Drive, Suite 300, Meridian, Idaho 83642 (208) 888-7010 Fax: (208) 888-7924
TEST PIT L 0 G
320
LOGGED BY: LJL
PROJECT #: 1867-ID1 METHOD: Backhoe
PROJECT: Brickyard EXCAVATOR: Just Dig It
CLIENT: T -O Engineers, Inc DATE: 5/23/17
G E 0 T E K LOCATION: --43.639060,-116.3560° ELEVATION: —2623 Feet
SAMPLES
c
�,
o-
y
E
N
TEST PIT NUMBER: TP -2
c
H
REMARKS
E
O
U
O
p
M>
m
N
=
MATERIAL DESCRIPTION AND COMMENTS
ML
Brown SILT with Sand w/ organics; Slightly Moist
so
Weed Ground Cover to V-0°
1
F
2
3
S
4
PCEM
Tan Partially Cemented SAND; Slightly Moist
MH
"Hard Pan"
5
SW
Reddish Brown well Graded SAND; Slightly Moist
D
6
7
8
End of Test Pit @ 8'-0"
No Ground Water Encounterd
9
10-
11
12-
21314151617181920
13-
14-
15-
16-
17-
18-
19-
20-
320 E. Corporate Drive, Suite 300, Meridian, Idaho 83642 (208) 888-7010 Fax: (208) 888-7924
TEST PIT L 0 G
320
LOGGED BY: LJL
PROJECT #: 1867-ID1 METHOD: Backhoe
PROJECT: Brickyard EXCAVATOR: Just Dig It
CLIENT: T -O Engineers, Inc DATE: 5/23/17
G E 0 T E K LOCATION: — 43.6378 , -116.3559° ELEVATION: — 2620 Feet
SAMPLES
c
T
T
w
C d
Q
N
TEST PIT NUMBER: TP -3
C
ti
REMARKS
G
m
d
a
N
H
V
—
N
p
E
M
>
o
m N
O
MATERIAL DESCRIPTION AND COMMENTS
ML
Dark Brown SILT with Sand w/ organics; Slightly Moist
so
Weed Ground Cover to 1'-0"
1
ML
Brown SILT with Sand; Slightly Moist
F
2
3
S
PCEM
Tan Partially Cemented SAND and Gravel; Slightly Moist
MH
"Hard Pan'
4
5
aT
SM
Lt Brown Silty SAND; Slightly Moist
vID
GP
Lt Tan Poorly Graded GRAVEL with Silt & Sand and trace
vID
"Pit Run"
3" minus Cobblers; Slightly Moist
7
8
9
10-
11
End of Test Pit ell' -O"
Ground Water Monitor
No Ground Water Encountered
GW -1 Installed
12-
21314151617181920
13-
14-
15-
16-
17-
18-
19-
20-
320 E. Corporate Drive, Suite 300, Meridian, Idaho 83642 (208) 888-7010 Fax: (208) 888-7924
TEST PIT L 0 G
320
LOGGED BY: LJL
PROJECT #: 1867-ID1 METHOD: Backhoe
AS
PROJECT: Brickyard EXCAVATOR: Just Dig It
CLIENT: T -O Engineers, Inc DATE: 5/23/17
G G 0 T E K LOCATION: — 43.6377841 -116.3590 ELEVATION:— — 2620 Feet
SAMPLES
o
T
CL
i.
C
N
TEST PIT NUMBER: TP -4
U
H
REMARI(S
CL
v
o
o
;_
<n
m
o
N
MATERIAL DESCRIPTION AND COMMENTS
ML
Dark Brown SILT with Sand w/ organics; Slightly Moist
So
Weed Ground Cover to 1'-0"
Fill Cover
1
F
2
3
S
4
PCEM
Brown Partially Cemented SAND; Slightly Moist to Moist
MH
"Hard Pan"
5
GP
Lt Tan Poorly graded GRAVEL with Sand and trace 3" minus
VID
Percolation rate test P-2
6
Cobbles; Slightly Moist to Moist
Installed @ 6'-0"
7
8
9
Trace 6" minus Cobbles @ 9'-6"
10
11
End of Test Pit @ 11'-0"
Ground Water Monitor
No Ground Water Encounterd
GW -2 Installed
12
13-
314151617181920
14-
15-
16-
17-
18-
19-
20-
320 E. Corporate Drive, Suite 300, Meridian, Idaho 83642 (208) 888-7010 Fax: (208) 888-7924
TEST PIT LOG
320
LOGGED BY: LJL
PROJECT #: 1867 -IDI METHOD: Backhoe
Aa�
PROJECT: Brickyard EXCAVATOR: Just Dig It
CLIENT: T -O Engineers, Inc DATE: 5/23/17
G E 0 T E K LOCATION: -43.639121,-116.3603° ELEVATION: -2616 Feet
SAMPLES
c
T
T
w
C d
co
N
TEST PIT NUMBER: TP -5
C
N
REMARKS
O-
a
U
—
C
E
O
=
O
`-'
MATERIAL DESCRIPTION AND COMMENTS
CL
Dark Brown, Lean CLAY with organics; Moist
so
Weed Ground Cover to V-0°
ML
Brown SILT with Sand; Moist
F
1
2
3
4
GP
Poorly graded GRAVEL with Sand and Trace 3" minus
D
No "Hard Pan" Encountered
Cobbles; Slightly Moist
5
6
7
8
9
Trace 6" minus Cobbles @ 9'-0"
10-
11
12-
13-
End of Test Pit @ 13'-0"
Ground Water Monitor
No Ground Water Encountered
GW -3 Installed
14-
4151617181920
15-
16-
17-
18-
19-
20-
320 E. Corporate Drive, Suite 300, Meridian, Idaho 83642 (208) 888-7010 Fax: (208) 888-7924
FIELD TESTS AND OBSERVATIONS (1867-I03)
PERCOLATION TESTS
The infiltration rate was determined by conducting percolation tests for onsite soils. The infiltration
rate was determined in inches per hour in general accordance with Ada County requirements.
Infiltration rate results are presented below.
LOCATION
INFILTRATION RATE
TP -3 @ 11'-0"
(Inches/Hour)
(P-1) TP- I @ 6'-0"
24.00+
(P-2) TP -4 @ 6'-0"
24.00+
GROUND WATER MONITORING RESULTS
Ground water monitoring results are presented below. Ground water elevation results are recorded
in feet below existing grade.
LOCATION
GROUNDWATER
ELEVATION
TP -3 @ 11'-0"
ll' -O"+
TP -4 @ 11'-0"
1 1'-0"+
TP -5 @ 13'-0"
13'-00f+
ril J ;a 4 Z
LABORATORY TESTS RESULTS (I 867-ID3)
ATTERBERG LIMITS
Atterberg limits were performed on representative samples in general accordance with ASTM D 4318.
The results are shown in the following plates.
PARTICLE SIZE ANALYSIS
Sieve analyses were performed in general accordance with ASTM test method C 136 and ASTM C 117.
Test results are presented in the following plates.
RESISTANCE R -VALUE TESTING
Tests were conducted on representative soil samples, in general accordance with Idaho test method
T-8 and AASHTO T-190, to determine the soil's performance when placed in the base, subbase, or
subgrade of a road subjected to traffic.
LLOCATION R -VALUE @ 200
psi
TP -I @2.0'-3.0' 24
21MMUM MI
W
Z
IZ
1--
Z Z
W
U
of
W
IL
100
90
80
70
60
50
40
30
20
10
0
Particle Size Distribution Report
V R/'111V JILC - 111111.
%13" % Gravel % Sand % Fines
Coarse Fine Coarse Medium Fine Silt Clay
0 0 0 1 5 22 72
Test Results (ASTM C136 & ASTM C117)
Opening
Percent
Spec."
Pass?
Size
Finer
(Percent)
(X=Fail)
1/2"
100
Cu= Cc=
3/8"
100
#4
100
#8
99
#16
98
#30
96
#50
91
#100
82
#200
72
(no specification provided)
Source of Sample: TP -1 Depth: 2'-3'
Sample Number: 3108
Boise Office
320 E Corporate Drive Suite 300
Meridian, ID 83642
Ph— (208)888-7010
Fax (208) 888-7924
G E O T E K � .Seoteku—com
Material Description
silt with sand
Atterberg Limits (ASTM D 4318]
PL= 28 LL= 34 P1= 6
Date Received: 5/23/17 Date Tested: 5/24/17
Tested By: Sean Wright
Checked By: Luke Landriani, PE
Title: Senior Engineer
Client: T -O Engineers
Project: Brickyard
Date Sampled: 5/32/17
Classification
USCS (D 2487)=
ML AASHTO (M 145)= A-4(4)
Coefficients
D90= 0.2692
D85= 0.1879 D60=
D50=
D30= D15=
D90=
Cu= Cc=
Remarks
F.M.=0.33
Date Received: 5/23/17 Date Tested: 5/24/17
Tested By: Sean Wright
Checked By: Luke Landriani, PE
Title: Senior Engineer
Client: T -O Engineers
Project: Brickyard
Date Sampled: 5/32/17
ry
W
Z
LL
I—
Z
W
U
W
a-
100
90
80
70
60
50
40
30
20
10
0
Particle Size Distribution Report
%13"
%+3" % Gravel
Coarse Fine
0 0 0
VI\f\IIV JILL - 111111.
% Sand
Coarse Medium Fine
0 5 16
Test Results (ASTM C136 & ASTM C117)
Opening
Percent
Spec.*
Pass?
Size
Finer
(Percent)
(X=Fail)
1/2"
100
3/8"
100
#4
100
#8
100
#16
99
#30
97
#50
92
#100
87
#200
79
(no specification provided)
Source of Sample: TP -5 Depth: 0.5'-1.0'
Sample Number: 3109
Boise Office
320 E Corporate Drive Suite 300
Meridian, ID 87642
Phone(208)888-7010
Fax (208) 888-7924
G E O T E K v ww.geotekuma nn
silt with sand
% Fines
Silt
79
Material Description
Atterberg Limits (ASTM D 4318
PL= 25 LL= 30 P1= 5
Classification
USCS (D 2487)= ML AASHTO (M 145)= A-4(3)
Coefficients
D90= 0.2222 D85= 0.1247 D60=
D50= D30= D15=
D10= Cu= Cc=
Remarks
F.M.=0.25
Date Received: 5/23/17 Date Tested: 5/24/17
Tested By: Sean Wright
Checked By: Luke Landriani, PE
Title: Senior Engineer
Client: T -O Engineers
Project: Brickyard
Date Sampled: 5/23/17
,
,
,
,
LIQUID AND PLASTIC LIMITS TEST REPORT
60
Dashed line indicates the approximate
upper limit boundary for natural soils
---- CL -ML
i
50
40
X
W
0
z
U 30
U)H
J
0.
ev
20
10
11
ML ®r
L
MH or
OH
0
0 10 20 30 40 50 60
70 80 90 100 110
LIQUID LIMIT
MATERIAL DESCRIPTION
LL
PL
PI
%<#40
%<#200
uSCS
•
silt with sand
34
28
6
94
72
ML
■
silt with sand
30
25
5
95
79
ML
Project No. 1867-ID1 Client: T -O Engineers
Remarks:
Project: Brickyard
•Source of Sample: TP -1 Depth: 2'-3' Sample Number: 3108
■Source of Sample: TP -5 Depth: 0.5'-1.0' Sample Number: 3109
Boise Office
310 E Corporate Dr. Suite 200 Meridian, ID 83612
Phone (208) 808-70 10 Pax (208) 888-7921
G E O T E K —g—O k.`a--
Report Date
,
,
,
,
'
'
---- CL -ML
i
Tested By: Josh Krause Checked By: Luke Landriani, PE
R -VALUE TEST REPORT
100
80
60
a�
CU
40
20
0
100 200 300 400 500 600 700 800
Exudation Pressure - psi
Resistance R -Value and Expansion Pressure - Idaho T-8
Expansion
Compact. Density Moist.
No. Pressure o Pressure
psi p /o
cf psi
Horizontal Sample Exud. R
R
Press. psi Height Pressure Valu
@ 160 psi in. psi Value Corr
1 100 105.2 20.1 0.30
88 2.54 221 32 32
2 100 103.8 20.8 0.06
1022.54 203 25 25
3 100 103.3 21.4 0.00
114 2.51 181 19 19
Test Results
Material Description
R -value at 200 psi exudation pressure = 24
silt with sand
Project No.: 1867-ID1
Tested by: Sean Wright
Project: Brickyard
Checked by: Luke Landriani, PE
Source of Sample: TP -1 Depth: 2'-3'
Remarks:
Sample Number: 3108
Date: 6/9/2017
Boise Office
320 E Corporate Or. Suite 700 Meridian, ID 8362
Phone(208)888-7010 Fix(208)888-7924
G E O T E K ww .8eotekumcorn
Report Date 6/7/1