HomeMy WebLinkAboutApp D.1 FINAL GEOTECHNICAL SITE ANALYSIS FOR KALALOCHMay 18, 2016
NORTHWESTERN TERRITORIES, INC.
717 SOUTH PEABODY STREET. PORT ANGELES, WA 99352
Engineers Lirrb Sun*yOra : Gecicq�:'s
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Phone (364) 352-8491 1.800-653.5345 Fax 352-8498 E-Maili iniodnti4u tort
Blair, Church and Flynn Construction Engineers
451 Clovis Avenue, Suite 200
Clovis, California 93612
Attn: Mr. Isaac Wedam
FINAL REPORT
Subject: GEOTECHNICAL SITE ANALYSIS FOR THE NEW KALALOCH CABINS
JEFFERSON COUNTY, WASHINGTON PARCELS: 413273002,
413273004,413273005,413273006 & 413273007
1.0 BACKGROUND AND SCOPE OF WORK
NTI Engineering and Land Surveying (NTI) were requested by Blair, Church and Flynn
Construction Engineers to complete a geotechnical site analysis and foundation assessment for
the proposed Kalaloch Cabins project. The proposed site for the cabins is within the five
adjoining Jefferson County Parcels whose reference numbers are listed above. The site lies
north of the mouth of the Queets River along a coastal bluff on the Pacific Ocean. The subject
parcels, taken together, provide over 1200 feet of frontage on the ocean and an area of
approximately 19 acres on the west side of Highway 101. The site is in the Southwest Quarter
of Section 27 of Township 24 N., Range 13W., of the Willamette Meridian in Jefferson County,
Washington.
All of the building area in the subject parcels is bounded on the west by a coastal bluff. The
bluff rises to an elevation of approximately 75 feet from a coastal lagoon and wild backshore
area at the toe of the bluff. On average the bluff rises at a slope close to 45 degrees from the
horizontal while some sections of the bluff are as steep as 55 to 60 degrees from the horizontal.
The current plan calls for the construction of 20 to approximately 24 small visitor cabins within
the parcels between the highway and the rim of the bluff.
This study includes information on the geologic hazards of the site and recommendations for
geologic hazard buffers for the proposed cabins in addition to information regarding the
subsurface conditions. The geotechnical parameters for foundation design, a suggested pier -
type foundation design and construction advisories are also provided below. NTI Engineering is
also concurrently studying the on-site wastewater treatment and disposal options. During field
work 15 test pits were excavated and logged in the proposed project area provide a design
basis for wastewater system design and to provide insight into foundation conditions.
Fifteen test pits were excavated by back -hoe and logged at the site on March 16, 2016, after
reconnaissance work and utility locates. Soil samples were collected and tested at NTI's
laboratory and field testing and observations were made for soil texture, consistency, drainage
characteristics and the in-situ shear strength of the soil. Field work was completed by Glen
Wade, a professional engineering geologist and Trent Adams, a geotechnical engineer in
training, with the assistance of Steve Luxton, a geotechnical engineer, all employees of NTI
Engineering and Land Surveying.
Direct observations of the subsurface soil were made within the test pits to depths of about 6.5
feet. Exposures of the underlying formations were examined during traverses of the 1200 foot -
long marine bluff. The aerial image below shows the five parcels with Parcel 413273006 on the
north and 41327005 on the south. The rim of the coastal bluff corresponds approximately to
the west line of the forested area in the parcels below.
PHOTO #1
AERIAL VIEW OF THE SUBJECT PARCELS TAKEN IN 2005 (COURTESY OFJEFFERSON COUNTY)
2.0 SITE GEOLOGY AND THE SOILS AT THIS SITE
2.1 Surficial Soil Types
The Soil Conservation Service (SCS -USDA) Soil Survey classifies the local surface soils as
Calawah Silt Loam. This soil, which appears to be partly derived from wind-blown sand, is high
in fine particles and it has some clay content and plastic behavior due to extensive weathering
by the over 100 inches of rainfall that occurs within the area on average each year. Field
observations showed the Calawah Soils were limited in depth at this site and underlain by a
sturdy formation of alpine glacial outwash gravel. The main soil -forming events occurred here
about 15,000 years ago. Atterberg Limit testing carried out on the soil show a Plasticity Index
of approximately 9. This indicates that true clay mineral content is relatively low giving the soil
a semi -plastic behavior. Clayey soils of this type have persistently high moisture content and are
difficult to dry. (See Appendix)
2
PHOTO #2 VIEW OF THE PACIFIC AND LAGOONS FROM NEW KALALOCH CABINS SITE
2.2 Site Geology
United States Geologic Survey Geologists Roland Tabor and Bill Cady studied this region for over
ten years and in 1978 they published their monumental work, the Geologic Map of the Olympic
Peninsula. According to Tabor and Cady, the site is underlain by an alpine glacial outwash gravel
deposit of late Pleistocene age.
The sandy gravel outwash deposit exposed along the bluff contains mostly rocks from the
Olympic Mountains with the granitic rocks of the Continental Glaciation largely absent. A thin
soil of moist clayey silt, and silt loam overlies the outwash. These materials probably arrived at
the site as wind-blown fine sand.
Well logs from the area note the existence of a vertically extensive clayey formation beneath
the gravels. Tabor and Cady mapped a deposit of siltstone and sandstone of Miocene age (15
million years old) that outcrops a few hundred yards to the east. Experience in this region
suggests that the clayey formation at depth may be a highly weathered portion of the same
siltstone/sandstone unit.
The Queets River flows into the Pacific Ocean less than a mile to the south. At present, the river
current runs behind a longshore sand bar before broaching the bar and flowing into the Pacific
Ocean.
2.3 Test Pit Observations - The Average Soil Profile
Many test pits were constructed within the 19 -acre site as shown in the attached map of the
test pit locations. The test pits revealed a more or less typical, averaged soil profile as
summarized below and shown in the photograph below.
DEPTH SOIL DESCRIPTION
---------------------------------------------------------------------------
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0' to V 0"+/- Dark organic detritus with silt and fine sand, very loose, damp to wet
1' -0" to 2' 0"+/- Brown to gray clayey silt with organic content ( silt or clay loam ), soft,
seepage at the contact to the underlying impervious clayey silt
2'-0" to 4' 8"+/- Red -brown to yellow -gray clayey silt, soft, grading to medium stiff,
moist, likely to be restrictive to percolation of water
4'- 8"+/- to Depth Gray -brown to gray sandy GRAVEL, well graded, moderately dense, moist,
moderately well drained. Sandstone clasts are of Olympic origin.
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PHOTO #3 TYPICAL TEST PIT SHOWING FOREST DUFF OVERLYING CLAYEY SILTS
4
3.0 GEOHAZARDS AND SLOPE STABILITY
3.1 Observations and Information Related to Slope -Stability and Geo -Hazards
The bluff at this site is approximately 70 feet in height along most of its length. Most of the
escarpment has a slope of about 45 degrees from the horizontal but the uppermost ten or
fifteen feet of bluff is over -steepened to nearly vertical in some reaches of the bluff's rim. One
section of the bluff lying between lots 3004 and 3005 is prominent and stands at more than 55
degrees from the horizontal in some parts. The slopes here are well vegetated with an
understory of evergreen huckleberry, salal, Indian plum, salmon berry, ocean spray and sword
ferns. Sitka Spruce and Red Alder trees reinforce the bluff's rim and they make an important
contribution to slope stability along the bluff's rim.
Observations along the bluff showed that the outwash gravel formation underlies the whole
site and it appears to extend down to the beach level at the backshore area above the lagoons.
Although an exposure of gray clayey silt was observed near the toe of the bluff on the south,
the gravel appears to be vertically extensive on the face of the bluff. There is about a foot of
loose slope colluvium on the steep slopes here.
x
PHOTO #4
01
MOIST CLAYEY SILT UNDERLAIN BY GRAVEL IS COMMON IN THE SUBSURFACE
5
The gravel observed in test pits and the same gravel formation examined along the slope was
well -graded and relatively low in clay and silt. This material has high internal friction and it
offers good slope stability. A thorough examination of the bluff showed several zones of
seepage along the toe with most of the saturation in the lowest 15 feet of the bluff after a very
wet winter.
The presence of lagoons along the toe of the bluff suggests that the Queets River may have
coursed along the toe of the bluff in this area before broaching the coastal sand and gravel bars
that form along this reach of the Pacific's shoreline.
Recent geologic research must be considered in assessing the prudent setback and geologic
hazard buffers appropriate to this bluff. Brian Atwater, a United Sates Geologic Survey geologist
at the University of Washington, and other researchers have concluded that the Olympic
Peninsula will experience "subduction zone" earthquakes. There is a growing body of evidence
that a very large (possibly 9.0 magnitude) subduction zone earthquake and related tsunami
occurred in 1700. Several other ruptures along the Juan de Fuca Plate margin have occurred
since that event. These ruptures have generated large and dangerous earthquakes.
This series of subduction zone earthquakes have been driven by disturbances along the margin
of the Juan de Fuca Oceanic Plate in the offshore zone where it dives (subducts) beneath the
continental rocks. The fault -line and potential rupture zone is about 65 miles offshore from the
subject site -too close for any complacency.
Evidence of tsunamis (tidal waves) originating along the subduction zone has been found in
coastal sediments and through the offshore cores of submarine turbidity current deposits
(submarine landslide deposits) along the coasts of Oregon and Washington.
When such a subduction zone earthquake occurs, it may be much longer in duration, much
more energetic and far more destructive than the earthquakes that have occurred in the Puget
Sound Region and Western Washington within recorded memory. Due to the longer duration,
higher energy and the longer vibratory period, the expected motion of the ground is very large
and the potential for landslide generation is high. The probability of such an event occurring is
now thought to be about 1 chance in 350 per year or about one chance in seven during the next
50 years. Some researchers suggest that the Olympic Peninsula area is "overdue" for an
occurrence.
3.2 Discussion and Factors Regarding The Geo -Hazards At This Site
At this site, the internal friction of the gravel formations at depth offers some protection from
very large and deep-seated rotational landslides. Large rotational slides that might envelope a
large width of the platform are unlikely here due to the presence of the strong well- graded
gravel in the slope and relatively low groundwater saturation levels with good drainage above.
0
Some over -steepened sections along the top of the escarpment may routinely fail in prolonged
wet weather leading to a sudden loss of up to perhaps ten feet of bluff width. Raveling of the
gravelly slope and thin translational slides of the loose surface of the slope may also be the
cause of sudden loss of a few feet of width along the rim.
Due to the presence of well -drained gravels at depth and the significant age of the deposit, the
site appears to have no liquefaction hazard. The potential for lateral spreading is also very low
due to the apparent absence of saturated sands at depth beneath the site and the lack of
confining earth materials.
Although the Queets River lies a few thousand feet to the south, there is some possibility that
the Queets River could re -take what may have been its former channel at the toe of the slope
at this site. If this were to occur, the rate of erosion and the rate of slope recession would be
greatly increased.
The effects of a subduction zone earthquake at this site are difficult, if not impossible, to
predict with precision. Nevertheless, it is easy to imagine that the gravelly slopes along this
bluff could be loosened by five minutes of violent ground motion followed by several large
tsunami waves that may momentarily reach half the height of the bluff. While the escarpment
is probably high enough to avoid direct damage to cabins by tsunamis, the lower portion of the
slope would be deeply washed by enormous surging waves which may follow an earthquake.
Given these conditions, it is easy to imagine that 10 or 15 feet of the bluff's rim could slump
downward in an earthquake along with much of the gravelly soil on the slope itself. In the over -
steepened areas along the top of the bluff, an even wider zone of slumping and instability
should be anticipated.
3.3 The Recommended Geo -Hazard Slope Buffer
In consideration of the factors above and recognizing the limited width of the site, a geohazard
buffer of twenty-five (25) feet is recommended. This buffer should remain in a natural state
and the growth of native shrubs and trees should be encouraged.
The Critical Areas Ordinance and Development Code of Jefferson County require a further five
(5) feet of setback from the geo-hazard buffer to the foundation line of any building, so that the
total setback from bluff's rim to the foundation of permanent structures is 30 feet. Modest
decks that do not encroach into the geo-hazard buffer may be built within the setback zone.
Some use of the geo-hazard buffer by vacationing cabin occupants who hope to enjoy the view
shown in Photograph 1, above, is probably unavoidable. Due to the fact that the seismic hazard
is by far the most significant reason for providing a geo-hazard buffer here, it seems that some
low -impact and thoughtful uses of the buffer might be allowed since they are unlikely to affect
the slope's stability.
Thoughtful and low impact uses of the buffer might include narrow and natural footpaths,
selected low -impact view points with rustic benches and small fire pits that are well away from
native trees. In our opinion, none of these uses would significantly affect the bluffs stability
so long as native trees are preserved as much as possible.
3.4 Final Positions of Cabins To Be Verified By Engineering Geologist
NTI's land surveyors have mapped the bluff's rim at the site and planned positions of the
proposed cottages. In Computer Aided Drafting drawings some of the proposed cabins have
been positioned on the plans 30 feet from the bluff's rim. Due to the zig-zagging and
undulations along the bluff and differing amounts of over -steepening that were not seen in the
site survey, the bluff's rim setbacks scaled from site design drawings may be significantly more
or less than 30 feet once they are staked in the field.
To ensure that all local conditions are fully considered, the final positions of the cottages should
be reviewed by NTI after they are staked from the drawings. Thus, we recommend that the final
positions of the cottages be verified and adjusted as required within the recommended 30 foot
structure setback by the undersigned Engineering Geologist once their graphic footprints have
been staked in the field.
4.0 BUILDING FOUNDATION AND DRAINAGE DESIGN RECOMMENDATIONS
4.1 Prescriptive Spread Footings Under The International Building Code
Typical spread strip footings for foundation tee -walls and isolated footings may be designed
and constructed in accordance with the prescriptive requirements of the current International
Building Code. The design criteria outlined below will lead to a good result if carefully followed.
The New Kalaloch Cabin's site is overlaid with a layer of loose organic forest duff and loose clay
and silt loam soil that must be removed prior to placing any foundation. All excavations for
foundation footings must be carried down to a minimum depth of two feet (24 inches) from the
top of the soil. The silty clay soil at the bottom of the excavation should be compacted if it is
sufficiently dry in fair weather. Compaction effort in trenches and excavations for footings
should result in relative density of at least 91% of the Modified Proctor under ASTM D 1557. All
of the resulting prepared surface should feel uniformly firm under foot prior to placing concrete
footings. All footings should be a minimum of 18 inches in width.
• Vertical Bearing Capacity of Soil
Spread footings installed on soil prepared as noted above may be designed for an allowable
vertical load of 1500 pounds per square foot of bearing area.
8
• Lateral Load Capacity of Soil
Allowable lateral load on adjoining soil may be taken as 100 pounds per square foot per foot of
depth for the native silt soils at this site. Backfill should be compacted into place. If additional
lateral bearing is required, backfill the footings with imported clean pit -run sandy gravel with
less than 8 % fines passing the 200 sieve meeting the requirements for "Gravel Borrow" under
the Washington State Department of Transportation's Standard Specification (WSDOT) #9-
03.14(1). The lateral bearing capacity of this imported backfill material may be taken as 200
pounds per square foot per foot of depth if the gravel has been compacted in place to a relative
density of 92% under the ASTM D1557 testing procedure. Native well -graded gravel quarried
from the south end of the project area may meet this specification. Refer to the attached Soil
Classification & Gradation Report # 16070 in the Appendix.
• Sliding Resistance
Resistance to lateral sliding is governed by cohesion in the clayey silt soils of this site at a depth
of 24 inches. Design footings for a lateral sliding (shearing) resistance of 150 pounds per square
foot of foot basal area resulting from soil -to -footing cohesion.
• Seismic Site Class "D"
Due to the presence of moderately stiff alpine glacial sediments and underlying soft and
weathered rocks of Miocene age at depth, this site is assigned a Seismic Site Class D
• Wet Weather Procedure
If water occurs in footing excavations during winter work or if weak, muddy soil is encountered,
over -excavate the affected footing areas to a depth of three (3) feet and fill the bottom of the
trench with a foot of clean pit -run gravel replacement fill meeting the WSDOT specification for
"Gravel Borrow." Replacement fill should be compacted until it reaches a firm condition and
placed so that the top of the fill is 24 inches beneath the original surface of the ground. Do not
over -compact this fill if it is placed on wet clayey soil. Excessive compaction may weaken the
soil and the foundation.
4.2 Concrete Pier Foundation Alternatives Defined
Concrete or other structural piers may used at this site to take advantage of the much stronger
gravel soil typically lying at depths of more than five (5) feet at this site. If concrete or similar
piers are selected, please ensure that the Contractor follows the procedures and understands
the specifications below in completing the piers.
si
PROCEDURES FOR INSTALLATION OF CONCRETE PIERS AT THE NEW KALALOCH CABINS
• Standard Method
Pier post holes may be augured into the soil by tractor -mounted post hole augers. Clear duff
and top soil away before auguring holes for the piers. Holes for piers must be carried down into
the underlying gravel layer. In most areas of the site, the gravel will be encountered at about 5
feet of depth, but all holes should be deepened until the gravelly soil is encountered below the
silt and clayey soils. 16 -inch augers that are capable of 6 feet of depth are best for this work but
a 12 -inch auger with less depth capacity could be used if pier holes are started by hand
excavation work. Please see attached drawing; Version 2.0, of the "Typical Foundation Pier" for
New Kalaloch Cabins.
If desired, concrete may be poured against the ground in the resulting post holes. Use 6 -sack
concrete for the piers below ground level to restrict water penetration and retard rebar
corrosion. Concrete for piers may be mixed on site by hand if the work schedule requires it or if
time -dependent sloughing of augured holes is a problem. Use a rich concrete mixture and be
sure that the concrete is well consolidated by using a concrete vibrator or by actively rodding
the concrete as it is being placed.
Steel reinforcing "cages" may be prefabricated using #4 rebar and #3 ties and stirrups as shown
on the attached drawing. Stub out 30 inches of rebar to continue reinforcement into the
column above. Cages may be "plunged" into the fresh concrete and braced into plumb and
accurate alignment. Be sure that the rebar cages are centered within the holes so that the rebar
are well away from the surrounding soil. Keep soil and debris off of the fresh concrete at the
top -of -pier so that concrete to be placed later has direct contact with the clean surface of the
new concrete in the augured holes.
Column forms may be placed on the resulting piers and the form height adjusted to meet the
architectural requirements and to allow for embedment of anchorage for the cabin
substructure. Piers should not rise higher than 5 feet from the ground using the design
provided here. Continue the same concrete reinforcing to the column as noted on the drawing
with 30 inches of dowel lap to the upper "cage". Concrete for the upper columns should be at
least 3000 psi -28 day strength with air content at least 5% to not more than 7% to improve
frost resistance. In most cases, piers over 3 feet in height will require bracing to resist lateral
loads. This should be assessed by the project architect or structural engineer.
10
• Alternative Method
If post holes are unstable and sloughing cannot be overcome by improved using site -mixed
concrete to quickly fill the pier holes, tube forms may be inserted into the excavations
immediately after auguring the holes. Forms may then be aligned and plumbed and braced.
Tubes should be backfilled with imported %-inch crushed rock that is at least 60% fractured and
with less than 6% of silt and clayey fines. Crushed rock backfill should be tamped into place
beside the tube forms to improve the friction and to provide more lateral support. Complete
vigorous compaction of the area around the piers after the concrete is placed in the tube forms.
Rebar cages may then be inserted into the forms using galvanized wire centralizers to keep the
rebar cages centered in the tube forms. (If you have questions about this, please contact the
undersigned Geotechnical Engineer.)
Concrete for the upper columns should be at least 3000 psi -28 day strength with controlled air
content at least 5% to not more than 7%. Consolidate and vibrate the concrete to avoid "honey-
combing".
• Design Data For Foundation Piers
Piers installed as outlined above will be able to carry the following loads to the soil. (Be sure
that a compatible anchorage design for the cabin substructure is provided by the Structural
Engineer or Project Architect.)
• Allowable downward vertical load per pier 5.5 kips ( 5500 # ) per pier
• Allowable upward uplift load per pier - 0.8 kips (800 #) per pier
• Lateral force capacity per pier at ground level - 1.75 kips ( 1700 #) in any direction
• Unbraced lateral force capacity per pier 5 ft above ground - 0.35 Kips 350 pounds
• Seismic Site Class "D"
• Total compression settlement of soil
• Differential settlement expected
4.3 Slab -On -Grade Construction
Approximately W when footing substrate is
prepared as directed above
Approximately %" to W when footing
substrate is prepared as directed above .
Pier type foundation construction methods are recommended for this site rather than integral
slab and footing arrangements. If slab on grade construction is required follow these
recommendations.
Prepare slab areas by removing all dark duff and organic soils to a depth of at least one foot.
11
Backfill the resulting excavation with Gravel Borrow meeting WSDOT specification 9-03.14(1) to
adjust floor height well above the native ground grade. Compact the fill to 95% of the Modified
Proctor Optimal Density under ASTM D 1557 in thin lifts of not more than one foot. To ensure a
dry floor, provide a final lift of 4 -inches of Hillcar 7/8" to 3/8" Capillary Break Washed Crushed
Gravel from the Hillcar Quarry near Forks, Washington, or equal capillary break product. This
material should be compacted with a vibratory plate compactor until the resulting surface is
dense and unyielding. When prepared for concrete, the capillarity break gravel should have a
96% relative density under ASTM D 1557.
Once near the slab bottom grade, cover the base rock with a 6 mil minimum thickness vapor
barrier or as specified by the project Architect. A leveling course of 1 or 2 inches of well drained
sand may be placed over the vapor barrier at the discretion of the Contractor or Architect to
enhance the adsorption of concrete bleed water and improve concrete cure and finishing.
Reinforce the concrete slab as specified by the Structural Engineer or Architect. Ensure the
specified clear cover for floor reinforcement is observed.
4.4 Roof and Driveway Drainage May Be Routed To Dry Wells
A gray to light brown well -graded gravel was identified in all test pits from depths of about 5
feet downward. The attached sieve analysis of the material (Appendix 1) indicates that less than
2% of the material passes the 200 sieve and well -graded composition indicating good drainage.
Observations of this gravel in outcrops along the bluff suggest that this gravel is extensive in
depth and widespread under the area and that it will safely accept drainage water at moderate
rates in all weather conditions. Thus, this material may receive drainage from parking lots and
downspouts. Infiltration galleries of imported drain rock or free -draining crushed rock should
extend down through the overlying soil well into the gravel below. Use filter fabrics to avoid
contamination of the drain rock by silt and clay from the overlying soil.
4.5 Parking and Driveway Design Recommendations
To prepare the existing soil beneath parking and driveway areas, begin by removing dark
organic detritus (top soil) and excessively soft or wet soil. The resulting surface should be rough
graded and compacted (if it is dry enough to compact) to 88 percent of the Modified Proctor
Density under ASTM D 1557 prior to placing any aggregate base or embankment materials.
Some areas of the site are already ballasted with gravel that was likely to have been quarried
from the pit at the south end of the project area.
4.6 Pavement Sub -base Recommendations
Place a woven geotextile fabric as specified by the project Civil Engineer over the prepared
subgrade. In the areas where ballast has not already been placed, build up with 16 -inches of
Hillcar Quarry 2 -inch minus ballast or 16 -inches of "Gravel Borrow" meeting WSDOT
specification 9-03.14(1).
12
This material should be compacted in 12 -inch lifts with a plate compactor or vibratory roller to
a firm unyielding condition. When in this condition, the pavement sub -base gravel would have
a 95% relative density under ASTM D 1557. If wet weather work is required, 24 or more inches
of ballast or gravel may be required to obtain enough stability for equipment operation. In the
event of wet weather work, the sub -base thickness should be reviewed at the time of
construction by the Engineering Geologist or the Geotechnical Engineer.
4.7 The Geotechnical Engineer's Paving Recommendations
Parking lot paving and paving base will be as specified by the project Civil Engineer. The
suggestions below are those of the Geotechnical Engineer. A grading base of 7/8 inch minus
free -draining crushed rock (Hillcar 7/8"minus clean crushed rock) or alternative product
meeting WSDOT 9-03.9(3) for "Top Course" should be placed on the sub -base for grading.
A 6 -inch lift of this product should be shaped and compacted to 98% of the ASTM D 1557
relative density.
The Geotechnical Engineer recommends paving the resulting surface with at least 2.5 inches of
asphaltic concrete to ensure a sufficiently hot mix for better compaction and to obtain a longer
pavement life. The resulting pavement should have a minimum life of 25 to 30 years.
4.8 Avoid Winter Work
Winter or wet season work will be difficult and excessively expensive at this site. Therefore,
excavation and grading work should be planned for dry summer weather.
5.0 CLOSURE
If excessively wet or soft soils are observed in foundation areas or if conditions in the
subsurface vary significantly from those described herein, please notify the undersigned
Engineering Geologist immediately for on-site assistance. NTI Engineering offers on-site testing
of compaction, concrete and aggregates testing and building code construction inspections that
may be requested for this project.
Sincerely yours,
For NTI Engineering and Land Surveying
Glen Wade, PG, LEG
Lead Engineering Geologist
Steve S. Luxton MSc. PE
Senior Geotechnical Engineer
13
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A.
Q ;A,
Robert A. Leach MBA, PE
Principal Engineer
APPENDIX
DOCUMENTS OF THE APPENDIX:
1. Drawing of Typical Pier -Type Foundation - Version 2.0
2. Laboratory Soil Test Reports
Soil Classification Gradation # 16070
Atterberg Limits # 16073
Moisture Content # 16073
Atterberg Limits # 16072
Moisture Content # 16072
Atterberg Limit # 16071
3. Map of Test Pit Locations
14
APPENDIX 1
DRAWING OF TYPICAL PIER -TYPE FOUNDATION
VERSION 2.0
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S T R I DATE: NTI ENGINEERING & SURVEYING
DESIGNED BY: 5, LLJXTon/
NORTHWESTERN TERRITORIES, INC.
PROJECT: AIW ,(mss 4A,6DCN CARia/5 Engineers ■Land Surveyors ■Geologists
�' ' Construction Coordination ■Materials Testing
FOR: RCIc- 6o VST, ,EN5/,V>fE/Z5 717 SOUTH PEABODY . PORT ANGELES, WASHINGTON 98362 a (360)452-8491
SHT• OF / NTI www.nti4u.com info@ntKu.com
APPENDIX 2
LABORATORY SOILS TEST REPORTS
NTI MATERIALS TESTING LABORATORY. Specimen Control # 16070
„y,,,«„ - �� --y-- --y-,
Construction Inspection - Materials Testing
iN�P 7 717 SOUTH PEABODY, PORT ANGELES, WASHINGTON 983&'t,(360)4524491
SUIL GLASslrl%;A i IVN i
WET GRADATION/ USCS
Client:
��Blair,
Church, and FI nn
Date:
3/17/2016
Project.
Kalaloch Cabins
Sample taken
by:
G. Wade / T. Adams
BILLING INFORMATION
Material:
Native
Lab Account #:
BCFC1601-03
Source_:
New Kalaloch Cabins Site
Client Contact:
Tested By:
BC/ SRW
Email:
Date Tested:
3/21/2016
Phone#:
Test requested:
Wet / Dry Sieve:
Wet
Remarks:
Sample #3 taken from TP -15; Brown Sandy Gravel
Reviewed:
ieve Die (mm)
Sieve Size Dry Wt. (grams)
% Retained
% Passing
125.0
5"
0.0
0.0%
100.0%
Dry start weight:
11277.3
75.0
3"
1621.2
14.4%
85.6%
Dry weight after wash:
11089.9
50.0
37.5
2"
1.5"
1272.4
1217.3
11.3%
10.8%
74.3%
63.5%
Minus #200 Weight:
D10:
187.4
0.00
25.0
1"
1530.4
13.6%
50.0%
D30:
0.00
19.0
3/4"
938.6
8.3%
41.7%
D60:
0.00
12.5
1/2"
1432.4
12.7%
29.0%
Cu:
#DIV/0!
9.5
3/8"
673.3
6.0%
23.0%
Cc:
#DIV/0!
4.75
#4
320.8
2.8%
20.1%
Soil Classification:
2.00
#10
652.0
5.8%
14.4%
Moisture Content:
0.85
#20
403.7
3.6%
10.8%
.425
1Y40 379.8
3.4%
7.4%
.250
#60 355.1
3.1%
4.3%
0.15
#100 182.4
1.6%
2.6%
0.075
#200 110.5
1.0%
1.7%
0
Pan 187.4
1.7%
0.0%
100.00
ILI
l
l I I
!
l _
I
_-�--
�- -- --
90.00
80.00
70.00
60.00
50.00
40.00
>`
LL M
C
p i
L.
30.00
20.00
10.00
0.00
4
L
I L
100.00 10.00 1.00 0.10 0.01
Grain Size (mm)
REMARKS:
r.. fop
NTI MATERIALS TESTING LABORATORY
Engineers - Land Surveyors - Geologists
Construction Inspection - Materials Testing
NT/ 717 SOUTH PEABODY, PORT ANGELES, WASHINGTON 98362, '360)452-8491
Spec 011 Control # 116073
A178ROMG LIMITS
• ASTM D4318
Client: 1131air, Church, and Flynn Date: 3/17/2016
Project: IKalaloch Cabins Sample taken by: G. Wade / T. Adams
BILLING INFORMATION Material: Native
Lab Account M BCFC1601-03 Source: New Kalaloch Cabins Site
Project Manager: G. Wade Tested by: BC/TA
Client Contact: Isaac Wedam
Email & Phone: iwedam bcf-en r.com ; 559 326-1400
y line, Gray Clayey Silt
Sam le #4 taken from Toe of slope at North Propert
LIQUID LIMIT
DETERMINATION
Sample #
Moisture
Can/Lid #
Mass of
Can/Lid (g)
Mass of Can/Lid + Wet
Soil (g)
Mass of Can/Lid + Dry
Soil (g)
Mass ofMass
Dry Soil
of
Water (g)
% Water
Content
Number
of Drops
1
4
13.8
27.7
25.0
11.2
2.7
24.1
23
2
H3
13.8
1 28.8
25.9
12.1
2.9
24.0
28
3
H2
13.8
29
26.2
12.4
2.8
22.6
31
4
G1
13.8
29.1
26.1
12.3
3.0
24.4
26
PLASTIC LIMIT
DETERMINATION
Sample #
Moisture
Can/Lid #
Mass of
Can/Lid (g)
Mass of Can/Lid + Wet
Soil (g)
Mass of Can/Lid + Dry
Soil (g)
Dry Soil Mass of
(g)
Mass of
Water (g)
% Water
Content
Number
of Drops
1
H2
13.8
45.8
41.3
27.5
4.5
16.4
N/A
2
H3
13.8
42.3
1 38.4
1 24.6
3.9
15.9
N/A
3
G3
14.4
43.5
1 40.0
1 25.6
3.5
13.7
1 N/A
RESULTS
LIQUID LIMIT DETERMINATION
25.0 8
•
LIQUID LIMIT
24
24.0
-
PLASTIC LIMIT
23.0
z
L)
-
•
15
22.0
o!
a
PLASTICITY
INDEX
3 21,0
20.0
10 100
NUMBER OF DROPS
9
ti
NTI MATERIALS TESTING LABORATORY
Engineers — Land Surveyors — Geologists
qW Construction Inspection — Materials Testing
AfTl 717 SOUTH PEABODY, PORTMGElES, WASHNGTOH OM Gaol 4511.8481
Specimen Control #
I 16073
MOISTURE CONTENT
ASTM D2216
Client:
Blair, Church, and Flynn Consulting Engineers
Date: 3/17/2016
Project
Kalaloch Cabins
Sample Taken By: G. Wade / T. Adams
BILLING INFORMATION
Material: Native
Lab Account:
BCFC1601-03
Source: New Kalaloch Cabins Site
Project Manager:
Glen Wade
Tested By: B. Carey
Client Contact:
Isaac Wedam
Date Tested: 3/18/2016
Email:
iwedam@bcf-engr.com
Phone #:
(559) 326-1400
Remarks:
None
RESULTS
Wet Sample
Weight (g)
Oven Dry Sample
Weight (g)
Weight of Water in
Sample (g)
Moisture Content
N
905.6
743.2
162.4
1 21.85
NTI MATERIALS TESTING LABORATORY
qjw Engineers — Land Surveyors — Geologists
Construction Inspection — Materials Testing
JVW 717SOUTH PMMY, PM MWIEs. WASH TON K16Z (W) 452-W1
Specimen Control #
16072
MOISTURE CONTENT
ASTM D2216
Client:
Blair, Church, and Flynn Consulting Engineers
Date: 3/17/2016
Project
Kalaloch Cabins
Sample Taken By: G. Wade / T. Adams
BILLING INFORMATION
Material: Native
Lab Account:
BCFC1601-03
Source: New Kalaloch Cabins Site
Project Manager:
Glen Wade
Tested By: B. Carey
Client Contact:
Isaac Wedam
Date Tested: 3/18/2016
Email:
iwedam@bcf-engr.com
Phone #:
(559) 326-1400
Remarks:
INone
RESULTS
Wet Sample
Weight (g)
Oven Dry Sample Weight of Water in
Weight (g) Sample (g)
Moisture Content
N
224.0
166.3 57.7
34.7
NTI MATERIALS TESTING LABORATORY
Engineers — Land Surveyors — Geologists
Construction Inspection — Materials Testing
NTAI 717 SOUTH PEABODY, PORT ANGELES, WASHINGTON 98362, 360 452-8491
Specimen Control # 116072
ATTERBERG LIMITS
ASTM D4318
Client: 1131air,
Church, and Flynn Date:
3/17/2016
Project:
Kalaloch Cabins Sample taken by.,
G. Wade / T. Adams
BILLING INFORMATION Material:
Native
Lab Account #:
BCFC1601-03 Source:
New Kalaloch Cabins Site
Project Manager:
G. Wade/ T. Adams Tested by:
Client Contact:
Isaac Wedam
Email & Phone:
iwedam bcf-en r.com, 569 326-1400
Remarks:
Sam le could not be rolled to required thread thickness for plastic limit test. (Non -plastic)
Sam le #2 taken from TP -3; Yellow Brown Silty Clay
LIQUID LIMIT DETERMINATION
Sample #
Moisture
Can/Lid #
Mass of
Can/Lid (9)
Mass of Can/Lid + Wet Mass of Can/Lid + Dry
Soil Soil
19) (9)
Mass of
Dry Soil
(g)
Mass of % Water
Water Content
(9)
Number
of Drops
Ps
1
0.0
0.0 #DIV/0!
2
0.0
0.0 #DIV/0!
3
0.0
0.0 #DIV/0!
4
0.0
0.0 0.0
PLASTIC LIMIT DETERMINATION
Sample #
Moisture
Can/Lid #
Mass of
Can/Lid (g)
Mass of Can/Lid + Wet Mass of Can/Lid + Dry
Soil (g) Soil (g)
of
D Mass soli
Dry S
Mass of
Water (g)
% Water
Content
Number
of Drops
1
0.0
0.0
#DIV/0!
N/A
2
0.0
0.0
#DIV/0!
N/A
3
0.0
0.0
#DIV/0!
N/A
RESULTS
13.0
0
o
0
le
a
3
LIQUID LIMIT DETERMINATION
5
I
f
ji
!
�i
LIQUID LIMIT
PLASTIC LIMIT
NP
PLASTICITY
INDEX
12.0
1
10
NUMBER OF DROPS
100
NTI MATERIALS TESTING LABORATORY
Engineers - Land Surveyors - Geologists
Construction Inspection - Materials Testing
/VTI 717 sovrH PEABODY, PORT mGELES, wAsHINGTON 98362, 360)452 -mi
Specimen Control # 116071
ATTERBERG LIMITS
ASTM D4318
Client: 1131air,
Church, and Flynn Date:
3/17/2016
Prci ect:
I Kalaloch Cabins Sample taken by:
G. Wade / T. Adams
BILLING INFORMATION Material:
Native
Lab Account #:
BCFC1601-03 Source:
New Kalaloch Cabins Site
Project Manager:
G. Wade/ T. Adams Tested by: JBC
Client Contact:
Isaac Wedam
Email & Phone:
wedam bcf-en r.com; 559 326-1400
Remarks:
Sample #1 taken from TP -1; Gray Clayey Silt
LIQUID LIMIT DETERMINATION
Sample #
Moisture
Can/Lid #
Mass of
Can/Lid (g)
Mass of CantLid + Wet Mass of Can/Lid + Dry
Soil (g) Soil (g)
Mass of
Dryg))oil
Mass of
Water (g)
% Water
Content
Number
of Drops
1
B
13.8
24.5 19.8
6.0
4.7
78.3
31
2
A3
1 14.6
1 26 20.9
6.3
5.1
81.0
21
3
C4
13.8
1 25.1 20.1
6.3
5.0
79.4
23
4
PLASTIC LIMIT DETERMINATION
Sample #
Moisture
Can/Lid #
Mass of
Can/Lid (g)
Mass of Can/Lid + Wet Mass of Can/Lid + Dry
Soil (g) Soil (g)
Mass of
Dry ,oll
Mass of
Water (g)
% Water
Content
1
13.5
41.7 32.3
18.8
9.4
50.0
2
14.6
44.0 35.1
20.5
8.9
43.4
3
1
13.7
1 43.4 1 34.1
20.4
9.3
45.6
4
13.9
26.8 1 22.8
8.9
4.0
44.9
RESULTS
82.0
81.5
81.0
80.5
U0 80.0
a79.5
3 79.0
78.5
78.0
10
LIQUID LIMIT DETERMINATION
I
LIQUID LIMIT
l
1
I
79
E
PLASTIC LIMIT
i
;
1
45�
PLASTICITY
INDEX
f i
JJ
j
34
NUMBER OF DROPS
100
APPENDIX 3
MAP OF TEST PIT LOCATIONS