GM 12 19 Final Geotechnical and Construction Recommendaitons.pdf

158377846

M E M O R A N D U M Western Federal Lands Highway Division

610 E. Fifth Street Vancouver, WA 98661

DATE: December 9, 2019

TO: Mike Traffalis Project Manager

FROM: Robert Kraig Geotechnical Engineer

SUBJECT: Geotechnical Memo 12-19 Final Geotechnical and Construction Recommendations Public Access Enhancement to Willapa National Wildlife Refuge Stations 20+00 to 37+97

WA PACIFIC 2015(1)

Pacific County, WA

INTRODUCTION

This memorandum provides information and geotechnical recommendations for the Public Access Enhancement to the Willapa National Wildlife Refuge project (project). It presents the results of field reconnaissance, test pit explorations, Wildcat Dynamic Cone Penetrometer exploration at Dohman Creek, and the results from laboratory tests performed on select grab samples obtained during the test pit explorations. In addition, design and construction recommendations are also discussed.

PROJECT DESCRIPTION

The general vicinity of the project is located on the Long Beach Peninsula in southwest Washington near the mouth of the Columbia River and the Willapa National Wildlife Refuge (Refuge) with driving distance of approximately 21 miles from Astoria, Oregon. See Figure 1 for Project Location, and Figure 2 for Project Vicinity.

The purpose of the proposed project is to reconstruct and widen approximately 0.36 miles of the 67th Place road in Pacific County, Washington, up to the existing gate located at about Station 37+97. The proposed reconstruction includes a slight grade raise (approximately 12 inches, or less) and widening at the north shoulder with the construction of additional embankment to gain width at that side. The proposed project lies within the Riekkola Unit of the Refuge and begins at approximately MP 2.0 on the 67th Place road and terminates at about MP 2.36. The route is close to the populated area of Long Beach and is designated as a tsunami evacuation route leading to a designated assembly area.

Figure 1: Project Location

Figure 2: Project Vicinity

MP 2.0

MP 2.36

Project

Long Beach, WA

An additional 0.14-mile segment was added to the project (Station 37+97 to Station 46+65) following the WFLHD Geotechnical investigations and site reconnaissance. That segment is addressed as part of a study performed for the Refuge in 2017 and as such is not further addressed in this memorandum beyond this mention. It is our understanding that the report portion of that study that is specific to the added segment will be provided as part of the supporting documents for the project.

GEOLOGY

The general area lies along the westernmost exposed edge of the central Washington and Oregon Coast Range and is in an area with several major estuaries and adjacent highlands that are reported to reach 2000 feet. Natural bedrock exposures in the wider area are typically restricted to stream courses along larger drainages, but were not observed near the project during our site reconnaissance. The elevation at the project location is approximately 10 feet above sea level.

Reference to the geologic map shows that the project (up to the gate) is located within a mapped unit of Fluvial and Estuarine Deposits (Qf, Holocene) described as unconsolidated clay, silt, sand, and gravel alluvium deposited along rivers and streams; also includes stabilized tidal flat deposits along the Columbia and Naselle Rivers and in Shoalwater Bay.

The segment of the project addressed in this memorandum is bounded at the beginning and end by mapped units of Sand of Mountain Springs (Qm, Pleistocene) described as semi-consolidated, laminated to massive, fine to coarse sand; commonly with yellow-orange to red iron oxide staining and characterized by planar lamination, broad gently dipping cross lamination, trough cross lamination, and localized channel fill with quartzite pebble stringers;

forms hills east of the town of Long Beach up to 100 m (300 feet) above sea level; may represent remains of an older barrier beach and dune field. Note that yellow-orange to red iron oxide staining as described above can be seen in Photo 13.

An excerpt from the geologic map is provided as Figure 3. As shown in the map excerpt, the project is located approximately 1 mile from the Shoalwater Syncline and about 2 miles from the Chinook Fault. Quick reference to the USGS Quaternary Fault and Fold Database of the United States did not show this fault but does show the southern extent of the closest fault zone, the Willapa Bay fault zone, at about 4 miles to the northeast of the project site. The Willapa Bay fault zone is defined as a thrust fault of Middle and late Quaternary (< 1.6 million years) with an undefined dip direction and slip rate between 0.2 and 1.0 mm/yr.

Figure 3: Excerpt from the Geologic Map of the Cape Disappointment-Naselle River Area

SITE CONDITIONS

The WFLHD Geotechnical Section conducted site reconnaissance in November 2016 and again in August 2017 and September 2018 for Dynamic Cone Penetrometer and test pit explorations as discussed below. Project photos are provided in Attachment 1. (The attachment also includes photos taken by other WFLHD design team members with dates other than those shown above.)

The project is located along the 67th Place road beginning at about Milepost (MP) 2.0 and ends at approximately MP 2.36 as shown in Figure 2, and is bound on each side by Refuge land on flat topography, generally covered in thick grassy matting that was once likely part of the Willapa Bay estuary (Qf unit described earlier). The project limits transition out of and into gently sloping ground that appears to define the Qm unit described earlier.

The 67th Place Road as it runs through the project is narrow with an oiled gravel or chip sealed surface. The road shows a high degree of distress and disintegration (Photos 4, 8, and 10), as evident in the form of large potholes that in some areas extend the full width of the road and in other areas where the driving surface has been lost at the shoulder (Photos 2, 3 and 7). It is thought that the travel surface resulted from the accumulation of chip seals rather than from a formal pavement structure. Compounded with the condition of the road was a failing culvert at the Dohman Creek crossing, which was replaced in late-August 2018 by Pacific County and as such is no longer a part of the proposed project.

The roadway and surrounding ground was wet during our site visit in November 2016 with many of the potholes described earlier filled with water, but was generally dry during our visits in August 2017 and September 2018.

Chinook Fault

MP 2.0 MP 2.36

The existing embankment is constructed of fill from an unknown source with an exposure evident in Photo 7, which appears to have been in place since the time of original road construction. While conducting test pit explorations (described in the next section), we observed that the driving surface flexed, and a bouncing sensation could be felt when standing at the shoulder as an empty dump truck passed by. This is typically an indicator of weak subgrade conditions.

SUBSURFACE CONDITIONS

The WFLHD Geotechnical Section conducted two simple subsurface explorations for the project. Explorations included using a hand-operated Wildcat Dynamic Cone Penetrometer (Wildcat) slightly off the north shoulder near the toe of the fill adjacent to the east side of the culvert at Dohman Creek in August 2017, and digging test pits in the first half and second half of the project (TP-1 and TP-2, respectively) in September 2018. The test pits were excavated through the driving surface to expose the fill and underlying native materials below to allow grab samples to be collected. The Wildcat and test pit locations are shown in Figure 4. The Wildcat exploration was advanced to 18.7 feet below the ground surface (BGS). Test pit TP-1 was advanced to 5.5 feet BGS and TP-2 was advanced to 6.3 feet BGS. Test pit tests were accomplished using a backhoe and operator provided by the County. The County’s culvert replacement work at Dohman Creek was nearing completion at the time of the test pit explorations.

Figure 4: Test pit and Wildcat Locations

MP 2.0

MP

2.36

TP18-01

TP18-02

Wildcat

Test Pits TP18-01 & TP18-02 Test pit photos are included in Attachment 1 as Photos 15 through 23 and the gINT logs are provided in Attachment 2.

As mentioned earlier, the driving surface was thought to be old chip seals with thickness measured at approximately 1.5 inches and underlain by a shallow fill of approximately 1 foot over native ground at each of the test sites. The fill consisted of silt, sand, gravel and cobbles with the fill at the TP18-02 location having a larger fraction of gravel (as can be seen in Photo 21), compared to the fill exposed at the TP18-01 location which had a smaller gravel fraction (no clear photo available). The gravel was observed to be angular to subangular and was markedly different from the underlying native soils in color and composition. The underlying soils were observed to be predominantly fine-grain and contained some scattered organics such as roots and other woody material. A 6-inch to 8-inch thick peat layer was encountered in TP18-01 at about 3.6 feet BGS. Grab samples representing the materials encountered in each test pit were collected and brought back to the WFLHD office for examination and possible testing.

Wildcat The Wildcat log is contained in Attachment 2.

The Wildcat is similar to a Standard Penetration Test (SPT) such that a hammer of a specific weight (35 pounds) is dropped at a prescribed height (24 inches), with successive blows to advance a rod into the ground, and the number of blows required to advance the rod is recorded for each 4-inch interval of penetration. Although sample collection is not possible with the Wildcat testing apparatus, the instrument is suitable for indicating changes in relative density (or consistency) between soil layers. The blow counts can be processed to correlate with SPT field N values. Based on these correlations the consistency of the fine-grain soil was shown to be very soft to soft in general, but appeared to become firmer at about 16 feet BGS. A zone was encountered between 2.6 and 5.9 feet BGS that was shown to have zero shear strength as evidenced by the probe dropping within that zone due only to its own weight. This is interpreted to be a void within this depth range. Because the test location was on the downstream end of the culvert, we interpret this void to be possibly scour related.

Lab Tests & Results Bulk Samples 2 from TP-1 and TP-2 were collected to representative the native in situ soils and were submitted to the WFLHD materials testing laboratory in Vancouver, WA following the test pit explorations. The tested samples were shown to classify as elastic silt (MH) in the Unified Soil Classification System (USCS). The fraction passing the #200 sieve in TP18-01 was shown to be 87 percent and in TP18-02 at 97 percent. The Liquid Limit in both samples was shown to be above 50 percent. The Plasticity Index (PI) in TP18-01 was determined at 22 percent moisture content and the PI in TP18-02 at 18 percent. In-situ moisture content varied considerably and was shown to be approximately 94 percent in TP18-01 and about 49 percent in TP18-02. Complete laboratory test results are included in Attachment 2.

Our observations and the results of the laboratory tests suggest that the in-situ subgrade conditions are very poor to poor.

Figure 5: Conceptual cross section

DESIGN RECOMMENDATIONS

The primary geotechnical consideration for this project is the need to stabilize soft/weak foundations soils in order to provide a reliable foundation for roadbed and embankment construction in a high groundwater environment, which has the potential for poor performance of the roadway.

The proposed design calls for increasing the roadway width. A conceptual detail is shown in Figure 5 that shows subexcavation and replacement and embankment construction against the existing embankment to gain additional top width to the north. The subexcavation and replacement with select borrow is intended to provide for removal of the organic layer encountered at the existing embankment edge. The base of the subexcavation should be lined with a separation-stabilization geotextile and a stabilization geogrid. The geotextile will prevent the fine soil materials from migrating into the select borrow and the geogrid will provide tensile resistance during construction and improved long-term performance. The depth of the subexcavation into native soils (not shown in the conceptual detail) should be a minimum of 2 feet.

It is likely that some improvement has resulted from stress increases (strengthening due to consolidation) in the subgrade zones beneath the existing embankment since the original decades-old construction. The new embankment will be constructed on very weak native soils that have yet to experience the type of stress increase that typically results from new embankment construction. Because of this, the potential for differential settlement is high due to the anticipated consolidation that is expected to occur beneath the newly embanked material relative to the somewhat strengthened and already consolidated subgrade beneath the adjacent existing embankment. We anticipate that any future differential settlement will be most noticeable at the paved surface in the form of uneven vertical displacements, particularly in a linear pattern longitudinally along the road above the transition where the newly constructed embankment meets the existing embankment. To help minimize this effect, a stabilization geogrid is recommended below the base course to help distribute stresses more evenly to the subgrade and to help bridge over the transition between the existing and newly-embanked material. This will serve to lower future maintenance efforts typically associated with this type of settlement, but will not completely eliminate the need. As a further mitigation measure, we recommend that the stabilization geogrid extend the full width of the road to address all potential “soft spots” and pothole areas observed within the existing embankment during the site visits.

CONSTRUCTION CONSIDERATIONS

The site reconnaissance, test pit explorations and laboratory test results have shown that the natural soils in the subgrade (elastic silts) will present problems in their ability to provide firm embankment support during construction and should be expected to be prone to settlement over time. Limiting differential settlement across the new roadway prism will be important. To address the primary geotechnical consideration of the very poor subgrade conditions, quality earthwork activities and special precautions will be important to the overall success of constructing new embankments.

As can be seen in Figure 5, a separation-stabilization geotextile is placed at the base and along the sides of the subexcavation to isolate the native elastic silt from the select borrow and to allow the select borrow to retain its strength by preventing migration of the elastic silt into it. Also included at the base of the excavation is a layer of stabilization geogrid to assist in stabilizing the subgrade base during embankment construction and thereafter.

Elastic silt is very sensitive to changes in moisture content and disturbance and can be prone to differential settlement when disturbed during and following construction. Because of this, we recommend that construction commence during the dry season when groundwater levels are expected to be at their lowest and the native soils would be in a “drier” and somewhat strengthened condition. According to the National Data Climate Center (NCDC) Summary of Monthly Normals for the period 1981 to 2010 (the latest period for this information to be available) the months with the least amount of mean precipitation are July and August with precipitation totals of 1.44 inches and 1.66 inches, respectively. Lower groundwater conditions should benefit soil compaction efforts during construction of the new embankment.

The NCDC Summary of Monthly Normals is provided as Attachment 3.

Constructability of the new embankments on the very weak subgrade soils will be a concern.

Sequencing of earthwork activities should be conducted in effort to absolutely minimize construction traffic over the subgrade soils, as the exposed subgrade materials will be very weak and possibly wet resulting in the potential for considerable problems in earthwork activities due to rutting/yielding subgrade that will require additional subexcavation and/or the potential for equipment delays. Conditions such construction timing, single lane use, and available areas for stockpiling of materials and equipment will have an impact on the overall means and methods utilized for this portion of the construction project. A “neat cut” excavation of the subgrade soils by means of equipment with a smooth-bladed bucket to limit disturbance to the sensitive elastic silts in the subgrade should be conducted off or above the planned subexcavation elevation. Following subexcavation of soft subgrade soils to a nominal depth of 2 feet, the separation-stabilization geotextile and stabilization geogrid (geosynthetics) should be rolled out on the prepared subgrade. Replacement materials (select borrow) should be placed in a manner to limit the potential for traffic on the subgrade. The first lift of select borrow should be placed utilizing an initial bridging lift on the order of 18 inches thick. The initial lift should be placed by pushing the replacement materials onto the geosynthetics using a small tracked dozer or similar equipment, no construction traffic should be allowed to operate directly on the geosynthetics without cover of replacement materials in order to protect them and the underlying subgrade. Following placement of the initial 18-inch lift of select borrow, the material should be compacted to a practical density target value with non-vibratory compaction rolling equipment (compression-type rollers) in accordance with Section 204.11(a) and with the intent of the bridging lift to provide a stable base for embankment construction without excessive effort to reach a level of compaction that may damage the subgrade.

To further limit the potential for differential settlement across the new roadway prism a stabilization geogrid will be placed between the base layer and the top of the select borrow subgrade for the full width of the roadway. This may be accomplished by rolling the stabilization geogrid in the direction of construction and overlapping 24 inches at roadway centerline in accordance with Section 207.04(b).

It is our understanding that limited road closures during construction will be allowed.

Contact the WFLHD Geotechnical Engineer if additional problems should arise during construction over the poor subgrade conditions.

REFERENCES

Geologic Map of the Cape Disappointment-Naselle River Area, Pacific and Wahkiakum Counties, Washington; Wells, Ray E.; U.S. Geological Survey; Map I-1832; 1989

USGS U.S. Quaternary Faults website:

https://usgs.maps.arcgis.com/apps/webappviewer/index.html?id=5a6038b3a1684561a9b0aad f88412fcf (accessed 4/18/2019)

National Data Climate Center, NOAA, National Centers for Environmental Information, U.S.

Normals Data (1981 – 2010), https://gis.ncdc.noaa.gov/maps/ncei/normals, Long Beach Experimental Station, WA US USC00454748 https://usgs.maps.arcgis.com/apps/webappviewer/index.html?id=5a6038b3a1684561a9b0aadf88412fcf https://usgs.maps.arcgis.com/apps/webappviewer/index.html?id=5a6038b3a1684561a9b0aadf88412fcf https://gis.ncdc.noaa.gov/maps/ncei/normals

CLOSING

Please contact robert.kraig@dot.gov at (360) 619-7699 with any questions regarding this memorandum.

RK

CC: Kristina Smith, Highway Designer

Megan Chatfield, Materials Engineer Jim Neighorn, Hydraulics Engineer Holly Weiss-Racine, Environmental Protection Specialist Eric Lim, Acting Geotechnical Functional Manager

Geotechnical File

Attachments: Attachment 1: Project Photos Attachment 2: Test Pit Logs, Wildcat Log, Lab Test Results

Attachment 1

- Project Photos

Intentionally Blank

Photo 1: Beginning of project looking to the east (Oct 2016)

Photo 2: Shoulder loss near middle of project looking west (Nov 2016)

Photo 3: Looking east at Dohman Creek (Nov 2016)

Photo 4: Looking west over Dohman Creek (Nov 2016)

Photo 5: Culvert at Dohman Creek inlet side (Nov 2016)

Photo 6: Culvert at Dohman Creek outlet side. (Oct 2016)

Photo 7: Embankment loss at Dohman Creek outlet side (Nov 2016)

Photo 8: Driving surface showing condition near end of proposed project (Nov 2016)

Photo 9: Parking lot near end of proposed project (Nov 2016)

Photo 10: Looking west from entrance of parking area (Nov 2016)

Photo 11: End of project at gate ahead (Nov 2016)

Photo 12: Road cut above gate at end of project (Nov 2016)

Gate at end of project

Road cut

Photo 13: Road cut beyond end of project (Nov 2016)

Photo 14: Road cut above gate showing silty sand exposure (Nov 2016)

Photo 15: Location of TP18-01 (Sept 2018)

Photo 16: TP18-01 (Sept 2018)

TP18-01

Photo 17: TP18-01 (Sept 2018)

Photo 18: Organics encountered in TP18-01 (Sept 2018)

Fill

Travel surface

Native

Photo 19: Location of TP18-02 (Sept 2018)

Photo 20: TP18-02 (Sept 2018)

TP18-02

Gravelly fill

Photo 21: TP18-02 gravelly fill (Sept 2018)

Photo 22: TP18-02 fill, organics and native soil (Sept 2018)

Native soil

Fill

Organics

Photo 23: TP18-02 fill, organics and native soil (Sept 2018)

Native soil

Fill

Organics

Travel surface

Attachment 2

- FLH Descriptive Terminology for Boring Logs

- Test Pit Logs

- Wildcat Log

- Lab Test Results

10/04/2018

SOIL CLASSIFICATION CHART

Criteria for Assigning Group Symbols and Group Name Using Laboratory TestsA Group

Symbol Group NameB

COARSE-GRAINED

SOILS

More than 50% retained on No. 200 Sieve

GRAVELS

More than 50% of coarse fraction retained on No. 4 Sieve

Clean GRAVELS Less than 5% fines E

Cu ≥ 4 and 1 ≤ Cc ≤ 3C GW Well-graded GRAVEL D

Cu < 4 and/or 1 > Cc > 3 C GP Poorly-graded GRAVEL D

GRAVELS with fines More than 12% fines E

Fines classify as ML or MH GM Silty GRAVEL D,F Fines classify as CL or CH GC Clayey GRAVEL D,F

SANDS

Less than 50% retained on No. 4 Sieve

Clean SANDS Less than 5% fines I

Cu ≥ 6 and 1 ≤ Cc ≤ 3 C SW Well-graded SAND H

Cu < 6 and/or 1 > Cc > 3 C SP Poorly-graded SAND H

SANDS with fines More than 12% fines I

Fines classify as ML or MH SM Silty SAND F,H Fines classify as CL or CH SC Clayey SAND F,H

FINE-GRAINED

SOILS

50% or more passes the No. 200 Sieve

SILTS and CLAYS Liquid limit less than 50

Inorganic PI > 7 and plots on or above the “A” line J CL Lean CLAY K,L,M PI < 4 or plots below “A” line J ML SILT K,L,M

Organic Liquid limit – oven dried Liquid limit – not dried < 0.75 OL Organic CLAY K,L,M,N

Organic SILT K,L,M,O

SILTY and CLAYS Liquid limit 50 or more

Inorganic PI plots on or above “A” line CH Fat CLAY K,L,M PI plots below “A” line MH Elastic SILT K,L,M

Organic Liquid limit – oven dried Liquid limit – not dried < 0.75 OH Organic CLAY K,L,M,P

Organic SILT K,L,M,Q

HIGHLY ORGANIC

SOILS Primarily organic matter, dark in color, and organic odor PT PEAT A Based on material passing the 3-inch sieve.

B If field sample contains cobbles or boulders, add “with cobbles” or “boulders” or both, to group name.

C Cu = D60/D10 Cc = (D30)2 / (D10 x D60) D If soil contains ≥15% sand, add “with sand” to group name.

E Gravels with 5 to 12% fines require dual symbols:

GW-GM well-graded GRAVEL with silt GW-GC well-graded GRAVEL with clay GP-GM poorly-graded GRAVEL with silt GP-GC poorly-graded GRAVEL with clay

F If fines classify as CL-ML, use dual symbol GC-GM or SC-SM G If fines are organic, add “with organic fines” to group name.

H If soil contains ≥15% gravel, add “with gravel” to group name.

I Sand with 5 to 12% fines require dual symbols:

SW-SM well-graded SAND with silt SW-SC well-graded SAND with clay SP-SM poorly-graded SAND with silt SP-SC poorly-graded SAND with clay J If Atterberg limits plot in hatched area, soil is a CL-ML, silty

CLAY.

K If soil contains 15 to 29% plus No. 200, add “with sand” or “with gravel”, whichever is predominant.

L If soil contains ≥ 30% plus No. 200, predominantly sand, add “sandy” to beginning of group name.

M If soil contains ≥ 30% plus No. 200, predominantly gravel, add “gravelly” to beginning of group name.

N PI ≥ 4 and plots on or above “A” line.

O PI < 4 or plots below “A” line.

P PI plots on or above “A” line.

Q PI plots below “A” line.

APPARENT DENSITY OF COARSE-

GRAINED SOIL

SPT N-value (blows per foot) Apparent Density

0 to 4 Very Loose

5 to 10 Loose

11 to 30 Medium Dense

31 to 50 Dense

> 50 Very Dense

CONSISTENCY OF

FINE-GRAINED SOIL

SPT N-value (blows per foot) Consistency

0 to 1 Very Soft

2 to 4 Soft

5 to 8 Firm

9 to 15 Stiff

16 to 30 Very Stiff

> 30 Hard

SOIL STRUCTURE TERMS

Stratified Alternating layers of varying material or color with layers > 1/4 inch (6 mm), note thickness and inclination.

Laminated(1) Alternating layers of varying material or color with layers < 1/4 inch (6 mm), note thickness and inclination.

Fissured(1) Breaks along definite planes of fracture with little resistance to fracturing.

Slickensided(1) Fracture planes appear polished or glossy, sometimes striated.

Blocky(1) Cohesive soil that can be broken down into smaller angular lumps which resists further breakdown.

Disrupted Soil structure is broken and mixed. Infers that material has moved substantially -landslide debris.

Homogeneous Same color and appearance throughout.

Lensed Inclusion of small pockets of different soil, such as small lenses of sand scattered through a mass of clay; < 1/4 inch (6 mm) note thickness.

(1) Do not use laminated, fissured, slickensided, or blocky for coarse-grained soils.

Descriptive Terminology for Boring Logs

Field descriptions of borings are based on the FLH Soil and Rock Description and Identification Guidelines that generally follow the Visual-Manual Procedure (ASTM D 2488). The soil classifications shown on the boring logs are based on laboratory tests (ASTM D 2487) when the two-letter group symbol follows the group name in parenthesis.

Standard Penetration Test (SPT): the SPT consists of driving a 2 in (50 mm) O.D. split barrel sampler a depth of 18 in (450 mm) or 24 in (600 mm) using a 140 lb (63.6 kg) hammer with a 30 in (750 mm) drop. The blow count is the number of blows recorded for each 6 inch (50 mm) increment.

The N-value is the total number of blows for the second and third increments. Note that the N-values shown on the boring logs do not include any corrections for non-standard sampler size, hammers, drill rods, etc.

ANGULARITY OF

COARSE-GRAINED SOILS

Angular

Sharp edges and relatively plane sides with unpolished surfaces

Subangular

Similar to angular description, but with rounded edges

Subrounded

Nearly plane sides, but will have well-rounded corners and edges.

Rounded

Smoothly curved sides and no edges

PARTICLE SIZE OF COARSE-GRAINED SOILS

Component Grain Size Limits

Boulders > 12” (> 300 mm)

Cobbles 3 – 12” (75 – 300 mm)

Coarse Gravel 3/4 - 3" (19 - 75 mm)

Fine Gravel #4 Sieve - 3/4" (4.75 - 19 mm)

Coarse Sand #10 - #4 Sieve (2.00 - 4.75 mm)

Medium Sand #40 - #10 Sieve (0.425 - 2.00 mm)

Fine Sand #200 - #40 Sieve (0.075 - 0.425 mm)

10/04/2018

GRAIN/CRYSTAL SIZE FOR ROCKS (MODIFIED AFTER WENTWORTH, 1972)

Grain Size Description Criteria Less than 0.003 inches (<0.075 mm)

Very fine grained Cannot be distinguished by unaided eye. Few to no mineral grains are visible with a hand lens.

0.003 to 0.02 inches (0.075 to 0.425 mm) Fine grained

Few grain/crystal boundaries are visible; grains can be distinguished with difficulty by the unaided eye but can be somewhat distinguished by hand lens.

0.02 to 0.08 inches (0.425 to 2 mm) Medium grained Most grain/crystal boundaries are visible; grains distinguishable by eye and with the aid of a hand lens.

0.08 to 0.2 inches

(2 to 4.75 mm) Coarse grained Grain/crystal boundaries are visible; grains distinguishable with the naked eye and hand lens.

Greater than 0.2 inches

(>4.75 mm)

Very coarse grained

Grain/crystal boundaries are Clearly visible; grains are distinguishable with the naked eye.

GRAIN SHAPE (FOR SEDIMENTARY ROCKS)

Description Characteristic

Angular Showing very little evidence of wear. Grain edges and corners are sharp. Secondary corners are numerous and sharp.

Subangular

Showing definite effects of wear. Grain edges and corners are slightly rounded off. Secondary corners are slightly less numerous and slightly less sharp than in angular grains.

Subrounded Showing considerable wear. Grain edges and corners are rounded to smooth curves. Secondary corners are reduced greatly in number and highly rounded.

Rounded Showing extreme wear. Grain edges and corners are smoothed off the broad curves. Secondary corner are few in number and rounded.

Well-rounded Completely worn. Grain edges or corners are not present. No secondary edges or corners are present. DEGREE OF WEATHERING

Term Description Grade

Fresh No visible sign of rock material weathering; slight discoloration on major discontinuity surface is possible. I

Slightly Weathered

Discoloration indicates weathering of rock material and discontinuity surfaces. All rock material may be discolored by weathering and the external surface may be somewhat weaker than in its fresh condition.

II

Moderately Weathered

Less than half the rock material is decomposed and/or disintegrated to a soil.

Fresh or discolored rock is present either as a discontinuous framework or as corestones. A minimum 2-inch (50 mm) diameter sample cannot be broken readily by hand across the rock fabric.

III

Highly Weathered

More than half of the rock is decomposed and/or disintegrated to soil. Fresh or discolored rock is present either as a discontinuous framework or as corestones.

A minimum 2-inch (50 mm) diameter sample can be broken readily by hand across the rock fabric.

IV

Completely Weathered

All rock material is decomposed and/or disintegrated to soil. The original mass structure is still largely intact. Material can be granulated by hand. If rock is considered to be completely weathered, use FLH Soil Description and Identification Guidelines to describe the residual soil material.

V

Residual Soil

All rock material is converted to soil. The mass structure and material fabric are destroyed but the apparent structure remains intact. There may be a large change in volume, but the soil has not been significantly transported. Material can be easily broken-down by hand. If rock is considered to be completely weathered, use FLH Soil Description and Identification Guidelines to describe the residual soil material.

VI

RELATIVE STRENGTH OF SOIL INFILLING (ISRM, 1978 & 1981)

Grade Description Field Identification Approximate

Uniaxial Compressive

Strength

S1 Very Soft Easily penetrated several inches by fist

<3.5 psi (<25 kPa)

S2 Soft Easily penetrated severl inches by thumb

3.5 - 7 psi (25 - 50 kPa)

S3 Firm

Can be penetrated several inches by thumb with moderate effort

7 - 14.5 psi (50 - 100 kPa)

S4 Stiff

Readily indented by thumb but penetrated only with great effort

14.5 - 36 psi (100 - 250 kPa)

S5 Very Stiff Readily indented by thumbnail

36 - 72.5 psi (250 - 500 kPa)

S6 Hard Indented with difficulty by thumbnail

>72 psi (>500 kPa)

RELATIVE STRENGTH OF INTACT ROCK SPECIMENS (ISRM, 1978 &1981)

Grade Description Field Indentificaiton Approximate Uniaxial Compressive Strength

R0 Extremely Weak Rock Specimen can be indented by thumbnail 35 - 150 psi

(250 - 1,000 kPa)

R1 Very Weak Rock

Specimen crumbles under sharp blow with point of geological hammer, and can be peeled with a pocket knife.

150 - 725 psi (1,000 - 5,000 kPa)

R2 Weak Rock Shallow cuts or scrapes can be made in a specimen with a pocket knife. A firm blow with a geological hammer point creates shallow indents.

725 - 3,500 psi (5,000 - 25,000 kPa)

R3 Medium Strong Rock

Specimen cannot be scraped or cut with a pocket knife.

Specimen can be fractured with a single firm blow with a geologic hammer point.

3,500 - 7,250 psi (25,000 - 50,000 kPa)

R4 Strong Rock Specimen requires more than one firm blow of the geologic hammer point to fracture.

7,250 - 14,500 psi (50,000 - 100,000 kPa)

R5 Very Strong Rock

Specimen requires many firm blows from the hammer end of the geologic hammer to fracture.

14,500 - 36,250 psi (100,000 - 250,000 kPa)

R6 Extremely Strong Rock

Specimen can only be chipped with firm blows from the hammer end of the geologic hammer.

>36,250 psi (>250,000 kPa)

JRC RANGES (ISRM, 1978 &1981)

DISCONTINUITY CONDITION (ISRM, 1978, 1981)

Condition Description

Excellent Condition

Very rough surfaces, no separation, hard discontinuity wall (>R2).

Good Condition

Slightly rough surfaces, separation less than ~0.04 inches (1 mm), hard discontinuity wall (>R2).

Fair Condition

Slightly rough surface, separation greater than ~0.04 inches (1 mm), soft discontinuity wall (<R3).

Poor Condition

Slickensided surfaces, or soft gouge less than ~0.2 inches (5 mm) thick, or open discontinuities between ~0.4 and 0.2 inches (1 to 5 mm).

Very Poor Condition

Soft gouge greater than ~0.2 inches (5 mm), or open discontinuities greater than ~0.2 inches (5 mm).

DISCONTINUITY SPACING (INCLUDES

JOINTS/FRACTURES, BEDDING, AND FAULTS

Description Spacing of Discontinuity Extremely Widely

Spaced >20 feet (>6 m)

Very Widely Spaced

~6 to 20 feet (2 to 6 m)

Widely Spaced ~2 to 6 feet (600 mm to 2 m)

Moderately Spaced

~8 inches to 2 feet (200 to 600 mm)

Closely Spaced ~2 to 8 inches (60 to 200 mm)

Very Closely Spaced

~3/4 to 2 inches (20 to 60 mm)

Extremely Closely Spaced

<3/4 inches (<20 mm)

𝑅𝑅𝑅𝑅𝑅𝑅 (%) =

𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿ℎ 𝑜𝑜𝑜𝑜 𝑆𝑆𝑜𝑜𝑆𝑆𝐿𝐿𝑆𝑆 𝐶𝐶𝑜𝑜𝐶𝐶𝐿𝐿 𝑖𝑖𝐿𝐿 𝑝𝑝𝑖𝑖𝐿𝐿𝑝𝑝𝐿𝐿𝑝𝑝 > 4 𝑖𝑖𝐿𝐿𝑝𝑝ℎ𝐿𝐿𝑝𝑝 (100 𝑚𝑚𝑚𝑚)

𝑇𝑇𝑜𝑜𝐿𝐿𝑇𝑇𝑇𝑇 𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿ℎ 𝑜𝑜𝑜𝑜 𝐶𝐶𝑜𝑜𝐶𝐶𝐿𝐿 𝑅𝑅𝑆𝑆𝐿𝐿

𝑥𝑥 100

𝐹𝐹𝐹𝐹 =

𝑁𝑁𝑆𝑆𝑚𝑚𝑁𝑁𝐿𝐿𝐶𝐶 𝑜𝑜𝑜𝑜 𝐿𝐿𝑇𝑇𝐿𝐿𝑆𝑆𝐶𝐶𝑇𝑇𝑇𝑇 𝑜𝑜𝐶𝐶𝑇𝑇𝑝𝑝𝐿𝐿𝑆𝑆𝐶𝐶𝐿𝐿𝑝𝑝

𝑇𝑇𝑜𝑜𝐿𝐿𝑇𝑇𝑇𝑇 𝑇𝑇𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿ℎ 𝑜𝑜𝑜𝑜 𝑝𝑝𝑜𝑜𝐶𝐶𝐿𝐿 𝐶𝐶𝐿𝐿𝑝𝑝𝑜𝑜𝑟𝑟𝐿𝐿𝐶𝐶𝐿𝐿𝑆𝑆 (𝑜𝑜𝐿𝐿𝐿𝐿𝐿𝐿)

𝐶𝐶𝑅𝑅 (%) = �

𝑇𝑇𝑜𝑜𝐿𝐿𝑇𝑇𝑇𝑇 𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿ℎ 𝑜𝑜𝑜𝑜 𝐶𝐶𝑜𝑜𝐶𝐶𝐿𝐿 𝑅𝑅𝐿𝐿𝑝𝑝𝑜𝑜𝑟𝑟𝐿𝐿𝐶𝐶𝐿𝐿𝑆𝑆

𝑇𝑇𝑜𝑜𝐿𝐿𝑇𝑇𝑇𝑇 𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿𝐿ℎ 𝑜𝑜𝑜𝑜 𝐶𝐶𝑜𝑜𝐶𝐶𝐿𝐿 𝑅𝑅𝑆𝑆𝐿𝐿 𝑅𝑅𝐶𝐶𝑖𝑖𝑇𝑇𝑇𝑇𝐿𝐿𝑆𝑆

� ∗ 100

S-0

S-1

S-2

S-3

S-2

S-4

Fines = 87%

Travel surface approximately 1.5" thick. (Accumulated chip seals?)

0.125 ft Silty, sandy gravel, yellow brown and light brown, damp, angular to subangular, some organics. FILL

1.125 ft Elastic SILT (MH), light gray, damp, some scattered organics. AASHTO A-7-5(25).

Natural moisture = 94.3%

3.6 ft Peat layer 6" to 10" thick.

4.3 ft Elastic SILT (MH), light gray, damp, some organics.

Fine roots (organics) observed at 5.3'.

5.5 ft

Bottom of test pit at 5.5 ft.

Groundwater Depth:

While Drilling: 5 ft At Completion: --- After Drilling: ---

Notes:

Latitude: 46.36025° Longitude: -123.997833° Date Started: 9/4/18 Date Completed: 9/4/18 Driller/Company: Pacific County/NA Hammer Type:

Drill: Backhoe

Logger/Company: Robert Kraig/FHWA

Sheet: 1 of 1 Project Location: Pacific County, WA

25 50 75 100

PL LLWC

N VALUE

10 20 30 40

Project Name:Public Access Enhancement to Willapa National Wildlife Refuge D ep th ft)

D ril lin g

M et ho d

Field Blow Count (Recovery)No. Test Results

T yp e

SAMPLE

MATERIAL DESCRIPTION

TP18-01

U. S. DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

FEDERAL LANDS HIGHWAY DIVISION

F H

W A

B O

R

IN

G L

O G

F

H W

A _D

A T

A T

E M

P

LA

T E

_2

3.

G

D T

/2 4/

:4

C :\M

Y F

IL

E

S \P

R O

JE

C

T S

\W

IL

LA

P

A N

A T

IO

N

A L

R E

F U

G E

\S U

B S

U R

F A

C E

IN

V

E S

T

IG

A T

IO

N

\S E

P T

T E

S T

P

IT

S \W

IL

LA

P A

N A

T

IO

N A

L W

IL

D

LI

F

E R

E F

U G

E .G

P J

G ra ph ic

L og

S-0

S-1

S-2

S-3

S-2

S-4

Fines = 97%

Travel surface approximately 1.5" thick. (Accumulated chip seals?)

0.125 ft Silty, sandy gravel, yellow brown to light brown and gray, damp, angular to subangular, some organics.

1.125 ft Elastic SILT (MH), light brown, damp, some scattered organics. Natural moisture = 49.5%. AASHTO:

A-7-5(23).

Organics observed at 1.4'.

1" to 2" layer of organics at 3.5'.

At bottom of hole transitions to light gray, some organics, increasing moisture but water not observed in hole.

6.3 ft Bottom of test pit at 6.3 ft.

Groundwater Depth:

While Drilling: --- Groundwater Not Observed At Completion: --- Groundwater Not Observed After Drilling: --- Groundwater Not Observed

Notes:

Latitude: 46.36275° Longitude: -123.994472° Date Started: 9/4/18 Date Completed: 9/4/18 Driller/Company: Pacific County/NA Hammer Type:

Drill: Backhoe

Logger/Company: Robert Kraig/FHWA

Sheet: 1 of 1 Project Location: Pacific County, WA

25 50 75 100

PL LLWC

N VALUE

10 20 30 40

Project Name:Public Access Enhancement to Willapa National Wildlife Refuge D ep th ft)

D ril lin g

M et ho d

Field Blow Count (Recovery)No. Test Results

T yp e

SAMPLE

MATERIAL DESCRIPTION

TP18-02

U. S. DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

FEDERAL LANDS HIGHWAY DIVISION

F H

W A

B O

R

IN

G L

O G

F

H W

A _D

A T

A T

E M

P

LA

T E

_2

3.

G

D T

/2 4/

:4

C :\M

Y F

IL

E

S \P

R O

JE

C

T S

\W

IL

LA

P

A N

A T

IO

N

A L

R E

F U

G E

\S U

B S

U R

F A

C E

IN

V

E S

T

IG

A T

IO

N

\S E

P T

T E

S T

P

IT

S \W

IL

LA

P A

N A

T

IO

N A

L W

IL

D

LI

F

E R

E F

U G

E .G

P J

G ra ph ic

L og

M = mass of hammer = 35 lb = 15.9 kg

H = height of drop = 24 in = 60.96 cm

Ap = projected area of the cone = 3.14 in2 = 20.3 cm2

M' = mass of the driven portion of the hammer = 5.49 lb = 2.5 kg

Nd = number of blows per 10 cm (4 in) of drive Pa = Mass of the rod string = 3.26 kg x the number of rods

Project : Willapa National Wildlife Refuge Project Number: WA Pacific 2015(1) Boring Number:

Boring Location:

# of Nd = blows RESIST* N'** Strt end Strt end rods per 10 cm kg/cm²

0.0 0.1 0.0 0.3 1 1 3.5 1 Very Loose V. Soft

0.1 0.2 0.3 0.7 1 2 7.0 2 Very Loose Soft

0.2 0.3 0.7 1.0 1 2 7.0 2 Very Loose Soft

0.3 0.4 1.0 1.3 1 2 7.0 2 Very Loose Soft

0.4 0.5 1.3 1.6 1 3 10.5 3 Very Loose Soft

0.5 0.6 1.6 2.0 1 3 10.5 3 Very Loose Soft

0.6 0.7 2.0 2.3 1 2 5.3 2 Very Loose V. Soft

0.7 0.8 2.3 2.6 1 2 5.3 2 Very Loose V. Soft

0.8 0.9 2.6 3.0 1 0 0.0 0 --- ---

0.9 1.0 3.0 3.3 1 0 0.0 0 --- ---

1.0 1.1 3.3 3.6 2 0 0.0 0 --- ---

1.1 1.2 3.6 3.9 2 0 0.0 0 --- ---

1.2 1.3 3.9 4.3 2 0 0.0 0 --- ---

1.3 1.4 4.3 4.6 2 0 0.0 0 --- ---

1.4 1.5 4.6 4.9 2 0 0.0 0 --- ---

1.5 1.6 4.9 5.2 2 0 0.0 0 --- ---

1.6 1.7 5.2 5.6 2 0 0.0 0 --- ---

1.7 1.8 5.6 5.9 2 0 0.0 0 --- ---

1.8 1.9 5.9 6.2 2 2 6.1 2 Very Loose V. Soft

1.9 2.0 6.2 6.6 2 2 6.1 2 Very Loose V. Soft

2.0 2.1 6.6 6.9 3 2 5.4 2 Very Loose V. Soft

2.1 2.2 6.9 7.2 3 2 5.4 2 Very Loose V. Soft

2.2 2.3 7.2 7.5 3 2 5.4 2 Very Loose V. Soft

2.3 2.4 7.5 7.9 3 2 5.4 2 Very Loose V. Soft

2.4 2.5 7.9 8.2 3 2 5.4 2 Very Loose V. Soft

2.5 2.6 8.2 8.5 3 2 5.4 2 Very Loose V. Soft

2.6 2.7 8.5 8.9 3 2 5.4 2 Very Loose V. Soft

2.7 2.8 8.9 9.2 3 2 5.4 2 Very Loose V. Soft

2.8 2.9 9.2 9.5 3 3 8.1 2 Very Loose Soft

2.9 3.0 9.5 9.8 3 2 5.4 2 Very Loose V. Soft

3.0 3.1 9.8 10.2 4 2 4.8 1 Very Loose V. Soft

3.1 3.2 10.2 10.5 4 4 9.7 3 Very Loose Soft

3.2 3.3 10.5 10.8 4 3 7.2 2 Very Loose Soft

3.3 3.4 10.8 11.2 4 4 9.7 3 Very Loose Soft

3.4 3.5 11.2 11.5 4 4 9.7 3 Very Loose Soft

3.5 3.6 11.5 11.8 4 6 14.5 4 Loose Soft

3.6 3.7 11.8 12.1 4 5 12.1 3 Very Loose Soft

3.7 3.8 12.1 12.5 4 5 12.1 3 Very Loose Soft

3.8 3.9 12.5 12.8 4 5 12.1 3 Very Loose Soft

3.9 4.0 12.8 13.1 4 6 14.5 4 Loose Soft

4.0 4.1 13.1 13.5 5 5 10.9 3 Very Loose Soft

4.1 4.2 13.5 13.8 5 6 13.1 4 Very Loose Soft

4.2 4.3 13.8 14.1 5 5 10.9 3 Very Loose Soft

4.3 4.4 14.1 14.4 5 6 13.1 4 Very Loose Soft

4.4 4.5 14.4 14.8 5 10 21.9 6 Loose Firm

4.5 4.6 14.8 15.1 5 9 19.7 6 Loose Firm

4.6 4.7 15.1 15.4 5 8 17.5 5 Loose Soft

4.7 4.8 15.4 15.7 5 8 17.5 5 Loose Soft

4.8 4.9 15.7 16.1 5 8 17.5 5 Loose Soft

4.9 5.0 16.1 16.4 5 9 19.7 6 Loose Firm

5.0 5.1 16.4 16.7 6 10 20.0 6 Loose Firm

5.1 5.2 16.7 17.1 6 9 18.0 5 Loose Firm

5.2 5.3 17.1 17.4 6 9 18.0 5 Loose Firm

5.3 5.4 17.4 17.7 6 9 18.0 5 Loose Firm

5.4 5.5 17.7 18.0 6 11 22.0 6 Loose Firm

5.5 5.6 18.0 18.4 6 10 20.0 6 Loose Firm

DYNAMIC CONE PENETROMETER ANALYSIS

DEPTH (m) DEPTH (ft)

North side of road at east side of culvert outlet

DENSITY/CONSISTENCY

0 50 100 150 200

**Correlated SPT N Value

*Dynamic cone resistance equation

Cone Resistance

( )10' ap d d PMMA

NHM

q rodsofnumberKgstringrodofMassP KghammerofportiondrivenMassM cmareaconeojectedAcmBlowsN cmHeightDropHKgmassHammerM a pd

26.3 49.2

10Pr,10/ 1.38,89.15

5.3 ' dqN =

Attachment 3

- NCDC Summary of Monthly Normals

U.S. Department of Commerce Summary of Monthly Normals 1981-2010

Generated on 10/16/2019

National Centers for Environmental Information National Oceanic & Atmospheric Administration 151 Patton Avenue National Environmental Satellite, Data, and Information Service Asheville, North Carolina 28801

Current Location: Elev: 25 ft. Lat: 46.3675° N Lon: -124.0377° W Station: LONG BEACH EXPERIMENTAL STATION, WA US USC00454748

Precipitation (in.)

Totals Mean Number of Days

Precipitation Probabilities Probability that precipitation will be equal to or less than the indicated amount

Means Daily Precipitation Monthly Precipitation

vs. Probability Levels

Month Mean >= 0.01 >= 0.10 >= 0.50 >= 1.00 0.25 0.50 0.75

01 11.79 22.9 17.0 8.3 3.5 8.18 11.69 15.15

02 8.40 18.7 14.0 5.9 2.3 4.78 7.25 11.43

03 8.64 22.5 16.0 6.3 2.0 6.86 8.17 10.27

04 6.26 20.1 12.6 4.2 1.3 4.33 5.42 8.34

05 3.81 16.8 8.9 2.2 0.6 2.83 3.83 4.87

06 2.94 14.0 7.1 1.7 0.3 1.78 2.83 3.99

07 1.44 11.6 3.6 0.7 0.1 0.70 1.06 1.75

08 1.66 10.9 3.7 0.8 0.3 0.72 1.36 1.90

09 2.58 12.3 5.7 1.6 0.4 1.02 2.39 4.19

10 7.20 18.5 11.7 4.9 1.6 4.89 7.35 10.07

11 12.26 22.3 17.4 8.5 3.6 8.14 11.21 16.32

12 11.67 22.1 16.6 8.2 3.6 8.86 11.75 13.99

Summary 78.65 212.7 134.3 53.3 19.6 53.09 74.31 102.27

-7777: a non-zero value that would round to zero

Empty or blank cells indicate data is missing or insufficient occurrences to compute value

Robert.Kraig Highlight

Robert.Kraig Highlight

Attachment 2- Lab Test Results