AZ_FLAP_439(1)_Martinez_Lake_Geotechnical_Report.pdf

Geotechnical Investigation Report Martinez Lake Road

U.S. Army Yuma Proving Grounds Yuma County, Arizona

AZ FLAP 439 (1)

Yeh Project No.: 214-248

October 31, 2016

Prepared for:

Jacobs Engineering Group 707 17th Street, Suite 2400 Denver, Colorado, 80202

Prepared by:

Yeh and Associates, Inc.

391 Front Street, Suite D

Grover Beach, California 93433

Phone: 805-481-9590

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Geotechnical Investigation Report Martinez Lake Road

U.S. Army Yuma Proving Grounds Yuma County, Arizona

AZ FLAP 439 (1)

Yeh Project No.: 214-248

October 31, 2016

Prepared by:

Jonathan D. Blanchard, G.E. (CA) Simon P. Boone Geotechnical Engineer Staff Geologist

Independent Reviewer:

Robert F. LaForce, P.E.

Senior Project Engineer

Geotechnical Investigation Report Yeh Project No. 214-248 Martinez Lake Road October 31, 2016 i

TABLE OF CONTENTS

1. PURPOSE AND SCOPE OF STUDY

2. PROJECT UNDERSTANDING

3. FIELD EXPLORATION AND TESTING

3.1 DRILLING

3.2 LABORATORY TESTING

4. GEOLOGIC SETTING

5. SITE CONDITIONS

5.1 TERRAIN AND VEGETATION

5.2 CLIMATE

5.3 EXISTING PAVEMENT SURFACE CONDITION

6. SUBSURFACE CONDITIONS

6.1 EXISTING PAVEMENT

6.2 SUBGRADE CONDITIONS

6.3 SUBGRADE PROPERTIES

7. GEOTECHNICAL RECOMMENDATIONS

7.1 EARTHWORK DESIGN

7.1.1 GENERAL GRADING

7.1.2 REUSE OF ON-SITE SOIL

7.1.3 EROSION AND SLOPE DRAINAGE

7.1.4 EARTHWORK FACTORS

7.1.5 EXCAVATION

7.1.6 SUBGRADE PREPARATION

7.2 GRADED SLOPE DESIGN

7.3 CULVERT DESIGN

7.4 PAVEMENT DESIGN RECOMMENDATIONS

7.4.1 DESIGN TRAFFIC VOLUME AND SUBGRADE

7.4.2 STRUCTURAL SECTION

ii

7.4.3 AGGREGATE SURFACE DETOUR ROAD

7.4.4 BINDER AND MIX RECOMMENDATIONS

7.4.5 PAVEMENT MAINTENANCE

8. MATERIAL SOURCES

9. LIMITATIONS

10. REFERENCES

List of Figures

FIGURE 1: PROJECT LOCATION MAP (NO SCALE)

FIGURE 2: REGIONAL GEOLOGIC MAP (RICHARD 1992)

FIGURE 3: EXPOSED ALLUVIUM ALONG MARTINEZ LAKE ROAD

FIGURE 4: TYPICAL SURFACE PAVEMENT CONDITIONS ALONG ROAD

FIGURE 5: TYPICAL EMBANKMENT WIDENING

FIGURE 6: SUMMARY OF RCB FOUNDATION PREPARATION AND BACKFILL

List of Tables

TABLE 1: EXISTING PAVEMENT CONDITIONS ENCOUNTERED

TABLE 2: GEOTECHNICAL PROPERTIES TEST SUMMARY

TABLE 3: SUMMARY OF REINFORCED BOX CULVERT LOCATIONS

TABLE 4: STRUCTURAL SECTION THICKNESS

TABLE 5: AGGREGATE SURFACE ROAD RECOMMENDATIONS

List of Plates

Plate Boring Location Map Box Culverts (Plan and Subsurface Profile) ........................................................................................... 2a – 2e

List of Appendices

Page Appendix A – Boring Logs Boring Record Legend ................................................................................................................................. A-1 Boring Logs 16B-01 to 05 for culvert locations .................................................................................... A-2 to 6 Borings Logs 16P-01 to 25 for pavement ........................................................................................... A-7 to 31 Photos of drill rig setups ................................................................................................................... A-32 to 37 file://SYNOLOGYGBCA/GB_Server/Projects%20-%20Grover/214-248%20Jacobs%20-%20Martinez%20Lk.%20Rd/1.%20Report/214-248%20Martinez%20Lake%20Road%20Geotechnical%20Report.docx#_Toc465674680 file://SYNOLOGYGBCA/GB_Server/Projects%20-%20Grover/214-248%20Jacobs%20-%20Martinez%20Lk.%20Rd/1.%20Report/214-248%20Martinez%20Lake%20Road%20Geotechnical%20Report.docx#_Toc465674682 file://SYNOLOGYGBCA/GB_Server/Projects%20-%20Grover/214-248%20Jacobs%20-%20Martinez%20Lk.%20Rd/1.%20Report/214-248%20Martinez%20Lake%20Road%20Geotechnical%20Report.docx#_Toc465674683 file://SYNOLOGYGBCA/GB_Server/Projects%20-%20Grover/214-248%20Jacobs%20-%20Martinez%20Lk.%20Rd/1.%20Report/214-248%20Martinez%20Lake%20Road%20Geotechnical%20Report.docx#_Toc465674685 iii

Appendix B – Results of Laboratory Testing Summary of Laboratory Test Results ................................................................................................... B-1 to 3 Atterberg Limits ........................................................................................................................................... B-4 Percent Passing No. 200 Sieve (%gravel, sand, fines) ........................................................................... B-5 to6 Mechanical Sieve Analysis, Summary of Results ................................................................................ B-7 to 10 Mechanical Sieves Analysis, Gradation Charts ................................................................................. B-11 to 22 pH and Resistivity ..................................................................................................................................... B-23 Proctor Compaction ......................................................................................................................... B-24 to 26 Consolidation Test ..................................................................................................................................... B-27 Consolidated Undrained Triaxial Test .............................................................................................. B-28 to 31 Resistance “R” Value Test ................................................................................................................ B-32 to 38 Appendix C – Pavement Design Calculations AASHTO (1993) Spreadsheet calculations ............................................................................................ C-1 to 3

1. PURPOSE AND SCOPE OF STUDY

Yeh and Associates, Inc., as a sub-consultant to Jacobs Engineering Group, Denver, Colorado, was retained by the Federal

Highway Administration (FHWA), Central

Federal Lands Highway Division (CFL) to provide geotechnical and pavement recommendations for the design of improvements to Martinez Lake Road in Yuma

County, Arizona. Martinez Lake Road is located approximately 20 miles northeast of

Yuma, Arizona and provides the only access from US Highway 95 to Fishers Landing and other recreational areas. The road crosses through the U.S. Army Yuma Proving Grounds and provides access for recreational use, 240 home sites, several hundred mobile home and recreational vehicle sites, the headquarters of the Imperial Wildlife Refuge, Meer Point

Recreational Area and the U.S. Marine’s Martinez Lake Recreational Area. The project location is shown on Figure 1.

The geotechnical evaluation consisted of a program of project coordination, reviewing project information, field exploration, laboratory testing, and engineering analyses as a basis for providing the recommendations in this report. This report provides recommendations for reconstruction of the road on a new vertical alignment, structural section thicknesses for the estimated traffic loading conditions, box culvert design, earthwork factors, slope design, compaction and fill placement for grading.

2. PROJECT UNDERSTANDING

Martinez Lake Road runs 10.5 miles from an intersection with US Highway 95 at milepost 46.7 to the Colorado River to the northwest. This project is to design and reconstruct a 5.89-mile segment of Martinez Lake Road, essentially the westerly half of the road alignment. Our

Figure 1: Project Location Map (no scale) understanding of the project is based on the Jacobs (2013) scoping report, and the Jacobs

(2015) preliminary plans, profile and cross sections.

The existing roadway is two lanes (one in each direction), paved with asphalt concrete, has a paved road width of approximately 26 feet and gravel shoulders. The existing roadway is constructed on a combination of cut and fill, with maximum heights of existing cut and embankment slopes ranging from about 10 to 15 feet. The existing embankments have typical side slopes inclinations of about 1v:2h or flatter. Cut slopes have inclinations up to about vertical to 1:1 with evidence of surficial erosion. Vertical curves along portions of the existing alignment have a low radius that limits site distance and/or are in low lying areas that are prone to flooding and washouts.

The roadway will be designed on essentially the same horizontal geometric alignment as the existing facility. The vertical alignment of the roadway will be changed to improve drainage, provide “all weather” access, and eliminate vertical curves within rolling topography that is associated with the poor sight distance. The improvements will generally consist of the following:

• The new roadway will have a paved width of 28 feet with 12-foot lanes, 2-foot paved shoulders, and 8-foot gravel shoulders. The wider road and grade changes will require widening of existing embankment and cut slopes in some areas. The earthwork for the project is expected to balance proposed cuts with fills.

• Embankments will raise the road grade by up to approximately 10 feet above centerline, particularly at drainage crossings with the deepest fills proposed near the proposed box culverts.

• Road cuts to lower the overall roadway profile will be constructed in some areas and to widening of existing cut slopes will be provide. The resulting cut slopes will be up to approximately 15 feet high. Through cuts will be deepened by up to approximately 12 feet below the existing centerline grade.

• Five reinforced concrete box (RCB) culverts are proposed for the project: a six-barrel

RCB at Station 1014+70, a five-barrel RCB at Station 1116+42, an eight-barrel RCB at

Station 1126+80, a four-barrel RCB at Station 1128+75, and a single-barrel RCB at

Station 1166+05. Cover heights range from approximately 2 to 3 feet.

• Approximately 36 new culverts are planned at various drainage crossings to improve drainage, including adding triple 24-inch pipes at Station 1320+50.

• New guardrail, signage, conforming to intersections, and erosion control along stream channels and drainages is also planned.

3. FIELD EXPLORATION AND TESTING

3.1 DRILLING

Drilling services were provided by Enviro-Drill, Inc. of Phoenix, Arizona. Quail Construction of

Yuma, Arizona provided traffic control and flagging for the drilling. Enviro-Drill used a truck-mounted CME 75 drill rig equipped with 8-inch diameter hollow stem augers to advance 30 borings during the period of January 12 to 14, 2016. Memoranda describing the field exploration program and findings were submitted by Yeh (2015, 2016). The approximate boring locations of the borings are shown on Plate 1. The logs of the borings are presented in

Appendix A. Photos of the road surface conditions at the boring locations are presented with the logs in Appendix A.

Deeper borings (to 10, 15 or 20 feet) were drilled in selected cut areas and where concrete box culverts and larger pipe culverts are proposed. The holes were sampled by collecting bulk samples of the pavement and subgrade materials from the auger flights, and by driving either a

2-inch standard penetration test (SPT) split spoon sampler or a 3-inch modified California split spoon sampler into the soil at various depths during drilling. Drive samples were typically taken at depths of approximately 1.5 and 4 feet below the road surface. Sampling below 4 feet was performed at 5-foot intervals. The modified California sampler contained 1-inch high brass liners. The SPT sampler was used without liners. The samplers were driven into the ground at the bottom of the boring using a 140-pound automatic trip hammer in accordance with ASTM

1586, the Standard Penetration Test. Yeh measured the thickness of the existing pavement and any base course materials encountered at each boring location, collected and secured bulk and drive samples for subsequent laboratory testing, recorded blow counts (N-values) for drive samples, and prepared a log of subsurface conditions encountered.

Upon completion, the borings were backfilled with auger cuttings and topped with asphalt cold patch. Groundwater was encountered in one borehole, 16B-01 (Station 1014+50) at a depth of

15 feet. Enviro-Drill obtained a well permit by from the Arizona Department of Water Resources to complete the drilling, and the borehole was backfilled with cement grout and capped with asphalt cold patch.

3.2 LABORATORY TESTING

Laboratory testing was performed on selected samples recovered from the field exploration program. Tests for classification and resistivity were performed at the Yeh office in Grover

Beach, California. Strength and consolidation tests were performed by the Geo-E lab at the

California Polytechnic State University, Civil Engineering Department in San Luis Obispo, California. BTC Labs of Ventura, California performed R-value Testing. Tests for moisture content, unit weight, Atterberg limits, percent passing the 200 sieve, particle size distribution by mechanical sieve analysis, pH and resistivity, compaction relationships between dry unit weight and moisture content using the modified Proctor test, consolidation, consolidated undrained triaxial compressive strength, and R-Value were performed as part of this program. The results of laboratory tests are presented in Appendix B. Testing was performed in accordance with applicable procedures of American Association of State Highway and Transportation Officials

(AASHTO) or ASTM. The soil descriptions were confirmed or modified as necessary on the boring logs based on the test results and further review of selected samples in the laboratory.

4. GEOLOGIC SETTING

Martinez Lake Road lies in a low-lying basin draining toward the Colorado River to the west.

The region is characterized by northwest trending mountain ranges and low drainage basins, typical landforms of the Basin and Range physiographic province. The surficial geology in the site vicinity as mapped by Richard (1992) is shown on Figure 2. The surficial units are mapped as Holocene-aged alluvium (Qs-Undivided alluvium and old alluvium). Mountain ranges in the area are mapped as Tertiary-aged volcanic rock of varying composition (Tba, Trt). The alluvial deposits encountered at the site consisted of intermixed sand, sandy gravel, with occasional clayey lenses (see photo on Figure 3). The drainage basin along Martinez Lake Road is dendritic with many small sandy drainages that cross or lie adjacent to the roadway alignment resulting in rolling topography. The ground surface within the surrounding landscape is typically covered by an accumulation of gravel sized particles that resulted from landscape armoring.

The armoring results when ongoing surficial erosion erodes away smaller sized particles leaving behind larger particles on the exposed surface

Figure 2: Regional Geologic Map (Richard 1992)

Figure 3: Exposed alluvium along Martinez Lake Road

5. SITE CONDITIONS

5.1 TERRAIN AND VEGETATION

Martinez Lake Road crosses undulating topography of the Colorado River alluvial plain and its tributary drainages. The surrounding landscape is sparse with vegetation that consisted of scattered sage brush, desert willow, and cacti, including Saguaro Cactus. Vegetation is relatively dense in the proximity to the Colorado River and along the drainage near the westerly terminus of the project. The ground elevation along Martinez Lake Road undulates through the dissected drainages. The ground elevation generally slopes downward to the west from the topographic high of el. 464 feet at the eastern project terminus to approximately elevation (el.)

194 at the western terminus of the project. The topographic low is el. 186 feet at the RCB location that will cross the westerly most drainage near Sta. 1014.

5.2 CLIMATE

The climate data (www.usclimatedata.com) for Yuma, Arizona (located approximately 20 miles south of the Martinez Lake Road area, reports an average annual rainfall of 3.09 inches. The majority of rainfall is reported to occur between August and October (monsoon season) and during winter months between December and March. The reported monthly average high temperature ranges from a low of 69 degrees for

December and January to a high of 107 degrees in July.

5.3 EXISTING PAVEMENT

SURFACE CONDITION

Photos showing the typical surface pavement conditions observed along Martinez

Lake Road are presented on

Figure 4. The exposed pavement surface along

Martinez Lake Road consisted of asphalt concrete with a posted Figure 4: Typical Surface Pavement Conditions along Road

Top left to right: Sta. 1052+80, Sta. 1292+00 Bottom left to right: Sta. 1050+50, http://www.usclimatedata.com/ limiting speed of 50 mph. The pavement was in poor to fair condition. The pavement generally had a raveled pavement surface; low to moderate block, fatigue and edge cracking; and localized but highly developed fatigue cracking, patches and deteriorating potholes.

6. SUBSURFACE CONDITIONS

The borings encountered units of existing fill and pavement materials overlying alluvium. The approximate locations of the drill holes are shown on Plate 1 and noted on the logs in Appendix

A. A description of the subsurface conditions encountered is summarized below.

6.1 EXISTING PAVEMENT

The existing structural section generally consisted of variable thicknesses of asphalt concrete pavement over aggregate base. The varying thicknesses of the layers may be associated with differences in past phases of roadway construction and maintenance, patching, seal coating, and repairs with additional base material having placed over the asphalt in some areas. The base materials were typically underlain by sandy subgrade soil. A summary of the thicknesses encountered in each of the borings is presented below:

Table 1: Existing Pavement Conditions Encountered

Boring Number Station

Asphalt Thickness (Inches)

Comments Boring

Number Station Asphalt

Thickness (Inches)

Comments

P-1 1011+00 4” 6” aggregate base

P-16 1222+00 2.5” --

P-2 1027+00 4.5” -- P-17 1232+55 3” --

P-3 1039+85 5” -- P-18 1243+80 3” --

P-4 1050+90 4.5” -- P-19 1255+60 4.5” --

P-5 1053+84 4” 2” aggregate base

P-20 1265+00 4” --

P-6 1062+50 5” -- P-21 1271+30 3” --

P-7 1075+00 3” -- P-22 1278+85 2.5” --

P-8 1087+84 3” -- P-23 1292+00 3.5” --

P-9 1100+45 3” -- P-24 1300+00 3” --

P-10 1142+15 3.5” -- P-25 1320+10 4.5” --

P-11 1151+60 2.5” 2” aggregate base

B-1 1014+25

4” asphalt 1” gravel 1” asphalt

P-12 1177+85 3” 3” aggregate

B-2 1116+50

4” asphalt 1” and

2” asphalt

5” aggregate

P-13 1190+45 5” --

B-3 1126+60 -- Drilled 6’ from right side

EOP

Boring Number Station

Asphalt Thickness (Inches)

Comments Boring

Number Station Asphalt

Thickness (Inches)

Comments

P-14 1196+10 2.5” -- B-4 1128+80 2.5” 4” aggregate Base

P-15 1211+00 3” -- B-5 1166+05 3” 2” aggregate Base

6.2 SUBGRADE CONDITIONS

Subgrade soil encountered below the structural section in each of the borings generally consisted of loose to medium dense sand and sand with gravel. The subgrade soil consisted of in place alluvial material and embankment fill associated with the construction of the existing

Martinez Lake Road. The fill appears to be derived from local alluvial sand and gravel that are predominant throughout the project area.

6.3 SUBGRADE PROPERTIES

Laboratory test results for drive samples had moisture contents ranging from approximately 1.2 to 14 percent and dry unit weights that ranged from approximately 83 to 129 pounds per cubic foot (pcf). Modified Proctor tests performed on bulk samples recovered from borings 16B-03, 16B-05 and 16P-14 had estimated maximum dry unit weights ranging from approximately 116 to

129 pcf and an optimum moisture content for compaction ranging from 4.8 to 10.2 percent.

The percentage of fines (less than No 200 Sieve) from wash samples and mechanical sieve analyses ranged from approximately 2 to 39 percent. Table 21 presents a summary of subgrade soil properties associated with the R-Value test results.

Table 2: Geotechnical Properties Test Summary

Sample Location γd.

(pcf) wo

Particle Size

Analyses (%G, %S, %F)

Atterberg Limits

LL, PI USC

ASSHTO

Group

Symbol R-Value

16P-01 130 2.6 45, 50, 5 --

Dense SAND with gravel and trace clay

(SP-SC)

A-1-a 65

1 Geotechnical properties are noted for dry unit weight (γd) and moisture content (wo); particle size as percent gravel (G), sand size (S) and fines content (F); Atterberg liquid limit (LL) and plasticity index (PI);

shear strength (S) in kips per square foot measured by pocket penetrometer (pp), torvane (tv) or unconsolidated undrained (uu) tests; friction angle (φ) or cohesion (c) in kips per square foot measured from direct shear (ds) or consolidated undrained (cu) tests.

Sample Location γd.

(pcf) wo

Particle Size

Analyses (%G, %S, %F)

Atterberg Limits

LL, PI USC

ASSHTO

Group

Symbol R-Value

16P-05 116 2.7 40, 56, 4 -- Medium dense

SAND with gravel

(SP)

A-1-a 59

16P-10 114 2.2 14, 77, 9 -- Medium dense

SAND with silt (SP-

SM)

A-3 63

16P-14 118 2.9 49, 49, 2 -- Loose to dense

SAND with gravel

(SP)

A-1-a 70

16P-20 83 3.0 4, 94, 2 -- Medium dense

SAND (SP) A-3 64

16P-25 119 4.2 19, 68, 13 -- Medium dense

SAND with silt and gravel (SW-SM)

A-1-b 47

Composite

AC

Grindings -- -- 37, 56, 7 -- SAND with gravel and silt (SP-SM) A-1 65

7. GEOTECHNICAL RECOMMENDATIONS

The recommendations of this report assume that grading, paving and fill materials will be placed and constructed in general accordance with Standard Specification FP-14. Compliance with those specifications is needed for the recommendations in this report to remain applicable.

7.1 EARTHWORK DESIGN

7.1.1 GENERAL GRADING

All site grading should conform to the applicable sections of FP-14. Fill materials should not contain organic matter or other deleterious material. Excess fill or cut material should be hauled offsite for proper disposal, unless an onsite location has been specifically identified for placement of excess fill on the project plans. Temporary excavations should conform to OSHA requirements.

7.1.2 REUSE OF ON-SITE SOIL

On-site soil removed from excavations and cleansed of topsoil, organics, clay lenses or clods, and oversized rock can be reused as borrow for general embankment fill and unclassified borrow. Fill materials should not contain organic matter or other deleterious material. The soil samples tested were typically 5 to 6 percent below the optimum moisture content for compaction. Moisture conditioning of the excavated soil will be necessary to make the material suitable for compaction. Existing base or excess FDR should be reviewed by the Engineer during construction prior to reuse as shoulder backing, base course or fill material.

Select areas of excavated on-site soil should be suitable for reuse as Foundation Fill (FP-14

704.01), Bedding (FP-14 704.02), Backfill (FP-14 704.03), Structure Backfill (FP-14 704.04), and Select Borrow (FP-14 704.07). Excavated soil may need to be screened to remove oversized particles, and segregated from unsuitable clayey or silty soil that should not be reused as select material. The excavated soil should not be considered suitable for reuse as aggregate

(FP-14 703) or rock (FP-14 705).

7.1.3 EROSION AND SLOPE DRAINAGE

The project site is within a desert environment with sparse vegetation and minimal to no topsoil development. Graded slopes will be vulnerable to erosion. Surface drainage should be maintained to allow the sheet flow of water similar to existing conditions and without concentrating flow or runoff. Maintenance and repairs to gullied or eroded areas should be performed promptly. Concentrated flows of runoff should not be allowed to run over slopes.

Overside drains, curbs, and drainages that convey surface water should be designed with appropriate erosion control and scour resistance surfaces. Downside drains should carry to the water the base of slopes before it is discharged. Energy dissipation devices should be provided at the outlet of pipes and ditches where concentrated flows of runoff may cause erosion.

7.1.4 EARTHWORK FACTORS

Earthwork factors2 were estimated for the subsurface conditions encountered. The subgrade encountered along the proposed vertical realignment of Martinez Lake Road generally consisted of sandy alluvial soil. It is recognized that disturbance to drive samples occurs due to compaction of samples during driving, and loosening of the soil when recovering the sampler from the drill hole and during trimming in the laboratory. Differences in soil density occur in areas that have been previously graded (the existing road subgrade), rodent borrows are present (particularly within the upper 2 feet of a site), and because of inherent differences in soil type and consistency.

2 The earthwork factor represents the ratio of the existing in-situ unit weight of the soil before construction to the unit weight of the same soil after compaction. For example, an earthwork factor of 0.95 represents a 5 percent loss in the volume of soil following compaction. An earthwork factor of 1.05 represents a 5 percent gain in volume of the soil or pavement following compaction due to bulking of a relatively dense material.

A 50 percent loss in volume should be used for the upper 1 foot of material in areas of undisturbed ground to account for losses due to grubbing, rodent burrows, and compaction.

Where on-site soil will be excavated for reuse as embankment fill, an average earthwork factor of 0.95 should be used. The earthwork factor should be reduced to 0.92 where the excavated soil will be used as fill that will be to at least 95 percent relative compaction. An earthwork factor of 0.97 should be used where the upper 2 feet of the existing subgrade is either compacted in-place or removed and replaced as compacted fill. The earthwork factors are approximate and should be checked and adjusted as-needed as the grading work progresses to properly balance earthwork operations.

7.1.5 EXCAVATION

Sandy alluvial soils containing varying amounts of gravel were encountered in the proposed cut areas along Martinez Lake Road. Excavation of the alluvial soils should be possible with conventional heavy earthmoving equipment and should not require heavy ripping or blasting.

The excavated soil is likely to contain gravel and cobble size materials, occasional boulders, and zones of riprap along existing stream channels. Oversized materials and zones of unsuitable soil will need to be removed from the excavated soil before it is considered suitable for reuse as compacted fill.

7.1.6 SUBGRADE PREPARATION

The roadbed should be prepared for placement of aggregate base or embankment fill materials in accordance with FP-14. Prior to placing fill or base course materials, the subgrade should be scarified to a depth of 9 inches, conditioned to a moisture content suitable for compaction, and compacted in-place to at least 95 percent relative compaction. The subgrade along the new road alignment should generally consist of medium to dense sandy material that should be suitable for the support of the new roadway and embankment fill. Where the existing alignment crosses alluvium deposits along the existing drainages, the subgrade should be reviewed following the initial subexcavation to evaluate whether or not additional soft or compressible soil is in place. If needed, additional subexcavation should be provided to remove soft or compressible soil prior to placing the embankment fill or culvert pipes.

7.2 GRADED SLOPE DESIGN

The proposed realignment will involve various embankment construction, excavation for cuts, and widening of existing cut and embankment slopes through undulating terrain with intervening drainages. Graded slopes should be designed to inclinations of 1v:2h or flatter. Where the embankment fill is placed adjacent to an existing embankment, the new fill should be keyed into the existing slope such that at least the outer 5-feet of the existing embankment is removed.

Figure 5: Typical Embankment Widening The keying can be performed in association with placement of the new fill, and such that the soil excavated from the existing embankment slope is simultaneously incorporated into the layer of the compacted fill that is being placed. The excavated material should be scarified and blended with the new fill to provide uniformity of material and moisture content that is suitable for compaction.

7.3 CULVERT DESIGN

Table 3 summarizes the locations and details for five reinforced concrete box (RCB) culverts that are shown on the Jacobs (2015) plans. Figure 6 presents a detail that shows the recommended preparation of the subgrade below the new culverts for a wet and dry case. The culverts will be cast-in-place and designed according to Arizona Department of Transportation

Standard Plans. The approximate bottom, maximum cover thickness estimated from Jacobs’ plans are also shown in Table 3 with a generalized description of the foundation soil encountered at each location.

Table 3: Summary of Reinforced Box Culvert Locations

Location Structure

Bottom (below existing grade)

Maximum Cover

Case per

Figure 6

Yeh Boring

No.

Generalized Foundation Soil

Encountered

1014+55 Six Barrel RCB 10 ft. span x 5 ft. high 2 ft. 2 ft. Wet 16B-01 Loose sand and shallow groundwater

1116+42 Five Barrel RCB at 45o skew 10 ft. span x 5 ft. high

1-2 ft. 5 ft. Dry 16B-02 Medium dense to dense sand and clayey sand with gravel

Location Structure

Bottom (below existing grade)

Maximum Cover

Case per

Figure 6

Yeh Boring

No.

Generalized Foundation Soil

Encountered

1126+80 Eight Barrel RCB at

45o skew 10 ft. span x 5 ft. high

2 ft. 4 ft. Dry 16B-03 Medium dense to dense sand with gravel

1128+75 Four Barrel RCB at 45o skew 10 ft. span x 5 ft. high

0.5-1.5

ft. 2 ft. Dry 16B-04 Medium dense to dense sand with gravel

1166+05 Single Barrel RCB at

45o skew 10 ft. span x 5 ft. high

2 ft. 2 ft. Dry 16B-05 Medium dense silty sand and sand with gravel

The recommended foundation preparation shown in Figure 6 should be provided below both the

RCB and the headwalls at the inlet and outlet of the culverts. The cutoff walls at the inlet and outlet ends of the RCB can extend the foundation preparation.

The foundation support for the RCB is generally good with the exception of RCB1014 where loose sand was encountered to a depth of about 13 feet below the proposed culvert. The foundation preparation for RCB1014 should conform to the wet case in Figure 6. Subexcavation to at 2 feet below existing grade, proof rolling the subgrade with a heavy vibratory roller, and placement of geogrid over the subgrade is recommended to help limit the estimated settlement of the culvert.

Figure 6: Summary of RCB Foundation Preparation and Backfill

The subgrade below the RCB should be excavated using an excavator or backhoe type equipment to avoid the need for construction traffic to operate on the subgrade. Proof rolling should consist of compacting the exposed subgrade with a 12-ton roller as noted on Figure 6. If the subgrade is soft and yielding under the vibratory load, the proof rolling should be completed with static loads and an additional four passes of proof rolling should be provided. Geogrid conforming to Section 714.03, Stabilization Geogrid, should then be placed over the subgrade in accordance with FP-14.

The foundation preparation for the remaining RCB should conform to the dry case in Figure 6.

The subgrade below the culvert excavations should be scarified to a depth of 9 inches, conditioned to a moisture content suitable for compaction, and compacted in-place to at least 95 percent relative compaction.

Compacted fill conforming to Section 704, Backfill Material, should then be placed over the prepared subgrade and to fill any voids or low spots left from the foundation preparation. A 3-inch layer of aggregate base course material conforming to Section 703.05b, Class E Base, should then be placed to the bottom of the box culvert elevation and be compacted to at least 95 percent relative compaction in accordance with FP-14. The recommended foundation preparation should limit the estimated settlement of the RCB to less than 1 inch total and to less than ¾ inches in 30 feet differential.

7.4 PAVEMENT DESIGN RECOMMENDATIONS

The minimum pavement design thickness for the new Martinez Lake Road is recommended based on design standards provided in Chapter 11 of the CFLHD Project Development and

Design Manual (PDDM) and the AASHTO (1993) Guide for the Design of Pavement Structures.

Preliminary pavement structural sections were evaluated and presented in the Yeh (2016) memorandum. Based on our evaluation and discussions with Jacobs, the concept to use new hot mix asphalt (HMA) over aggregate base was selected as being the appropriate alternative for this project. An alternate section is also provided to incorporate reclaimed pulverized asphalt from the existing structural section (full depth reclamation (FDR) material) into the new structural section as a subbase layer. The spreadsheet calculations for our recommended traffic loading and thickness recommendations are presented in Appendix C.

7.4.1 DESIGN TRAFFIC VOLUME AND SUBGRADE

The design traffic volume was estimated using the average daily traffic (ADT) and vehicle distributions provided by Jacobs in a memorandum received on February 2, 2016 and procedures in the Federal Lands Highway Project Development and Design Manual (FHWA

2014). Jacobs reported that the current seasonal average daily traffic (ADT) for Martinez Lake

Road is approximately 2,000 vehicles per day with 20.2 percent pickup trucks, 25.7 percent 2-axle trucks and 3.5 percent 4-axle truck. These data were used to estimate the number of 18-kip equivalent single axle loads (ESALs) considering a design life of 25 years. This design

ESAL value was 2,091,043 for Martinez Lake Road. Calculation of ESAL loads are presented in Appendix C.

The alluvial sand encountered along Martinez Lake Road generally classified as A-1 and A-3 with some areas of A-2 that are considered to provide good to excellent subgrade support for the roadway. R-values obtained from bulk samples ranged from approximately 47 to 70. The recommended structural section thicknesses were estimated considering a resilient modulus

(Mr) of 13,200 psi for the sandy subgrade encountered.

7.4.2 STRUCTURAL SECTION

Martinez Lake Road will be reconstructed along a new vertical alignment within the project limits. The recommended structural sections are based on the traffic loading conditions assuming a 25-year design life for a 4R project and a minimum structural number of 2.80. The alternative 3-layer section can be used to incorporate FDR material reclaimed from the existing structural section. The alternative 2- or 3-layer sections should not be alternated but should be applied to specific areas and defined limits or the entire reach of the roadway. The recommended structural section thicknesses are presented in Table 4.

Table 4: Structural Section Thickness

Alternative

Surface Course

HMA

(inches)

Base Course

AB

(inches)

Subbase Course FDR Material

(inches) Structural Number

2-layer Section 4 8 -- 2.88

3-layer Section 4 4 4 2.80

FDR can be reclaimed for reuse within the new structural section by pulverizing the existing asphalt pavement along Martinez Lake Road, harvesting and stockpiling the material (if needed), and then placing the material as subbase for the new structural section. The thickness of the existing pavement encountered in the borings ranged from approximately 2.5 to 5 inches thick, with an average thickness of 3.5 inches. Borings B-1 and B-2 encountered a second layer of pavement below a thin layer of soil that is likely associated with past washout and reconstruction of the roadway. Pulverizing should extend to at least 1 inch below the existing pavement. A typical depth of 5 inches of pulverization should be considered for design if FDR material is to be harvested for reuse within the new structural section.

Shoulder backing materials should be placed along the new edge of pavement (NEP) to support the pavement edge and reduce the potential for edge cracking. Shoulder backing should consist Class D base conforming to Section 7.03.05 of FP-14. Shoulder backing should be at least 3 inches thick at the NEP and extend at least 2 beyond the NEP.

7.4.3 AGGREGATE SURFACE DETOUR ROAD

Temporary detours may be used to direct traffic around construction areas where heavy grading is in progress. The detours will be aggregate surface roads that would likely be in use for less than one year. Aggregate surface roads are designed based on the anticipated traffic loading conditions. The guidelines for the design of gravel roads were not used for the analysis because the estimated traffic volumes for Martinez Lake Road are relatively high (2,000 ADT).

Compared to typical gravel roads, the detour is short-term and temporary, and the R-value of the subgrade soil encountered is relatively high that will provide good support for the detour.

The structural section for the detour is based on compacting the upper 9 inches of sand and gravel subgrade material to at least 95 percent relative compaction. A modulus for the subgrade

(19,500 psi) was selected for estimating thickness of the aggregate surface course based on the average R-value of the subgrade soil that was tested.

Table 5: Aggregate Surface Road Recommendations

Alternative Surface Course

(inches) Structural Number 18-kip ESALs Subgrade

Preparation

6-month detour

4” AB 1.28

41,821 Compact upper 9 inches to 95% relative compaction 5” FDR 1.32

1-year detour

5” AB 1.42

83,642 Compact upper 9 inches to 95% relative compaction 6” FDR 1.44

Maintenance of the aggregate surfaced detour will likely be necessary to control dust, repair wash-board or eroded surfaces, and maintain an adequate crown. The crown of the aggregate surface road should be graded to a typical cross slope of 4 percent to help minimum erosion and wash boarding. A dust palliative can be used to help reduce dust and the need for watering for dust control.

7.4.4 BINDER AND MIX RECOMMENDATIONS

The State of Arizona has adopted a program of Asphalt Binder Grade Selection that classifies this project area as a Desert Region. The recommended binder for this area is PG 70-10

(LTPPBind). This project is in a rural area and we understand the location of existing commercial asphalt plants may result in relatively long haul distance to the construction site

(see discussion in Section 8 of this report). Loss of temperature and segregation of the hot asphalt mix can occur during transport. We recommend that the project specifications require the use of a material transfer device at the point of placement to insure uniform temperatures and prevent segregation of the mix during placement.

7.4.5 PAVEMENT MAINTENANCE

The pavement condition should be periodically evaluated to help plan and scope the need for maintenance and rehabilitation following the initial construction of the pavement. Maintenance of asphalt concrete pavements should typically include periodic fog, chip or slurry seals to reduce the rate of weathering, and overlaying with additional HMA when needed to strengthen and further the life of the pavement. Deflection surveys can be performed to evaluate the structural capacity of pavements and the need for future overlays.

8. MATERIAL SOURCES

The main material requirements for this project are likely to be hot mix asphalt, aggregate base, and concrete. Earthwork is expected to be balanced for the roadway construction. While no specific contacts were made for this project, there are commercial suppliers of construction materials in Yuma, Arizona approximately 20 miles south of Martinez Lake Road on

Highway 95. Relatively long haul distances will make it necessary to monitor truck hauling and standby times, and to check mix temperatures arriving at the site and during placement.

9. LIMITATIONS

This study has been conducted in general accordance with currently accepted geotechnical practices in this area for use by the client for design purposes. The conclusions and recommendations submitted in this report are based upon the data obtained from field reconnaissance, drilling and sampling, and our understanding of the proposed project and type of construction described in this report. If there are any changes in the project or site conditions, Yeh should review those changes and provide additional recommendations, if needed. Any modifications to the recommendations of this report or approval of changes made to the project should not be considered valid unless they are made in writing. The report and drawings contained in this report are intended for design-input; and are not intended to act as construction drawings or specifications.

Site conditions will vary between points of observation or sampling, seasonally, and with time.

The nature and extent of subsurface variations across the site may not become evident until excavation is performed. If during construction, fill, soil, or water conditions appear to be different from those described herein, Yeh should be advised and provided the opportunity to evaluate those conditions and provide additional recommendations, if necessary. The geotechnical professional should observe portions of the construction and site conditions, such as excavations, exposed subgrades and earthwork, to evaluate whether or not the conditions encountered are consistent with those assumed for design, and to provide additional recommendations during construction, if needed.

10. REFERENCES

American Association of State Highway and Transportation Officials (AASHTO), AASHTO

Guide for Design of Pavement Structures, Washington D.C., copyright 1993.

Jacobs Engineering Group (2015), Plans Proposed for: AZ FLAP 439(1), Martinez Lake Road, Yuma County” 30 percent plans prepared for Federal Highway Administration, Central

Federal Lands Highway Division, submitted November 11, 2015.

Jacobs Engineering Group (2013), Federal Highway Administration, Central Federal Lands

Highway Division, Federal Lands Access Project Scoping Report, US Army Yuma Proving

Grounds & Imperial National Wildlife Refuge, Yuma County, Arizona, AZ FLAP 439(1), Martinez Lake Road 4R, submitted June 30, 2013.

Richard, S.M. (1992), Geologic Map of the Imperial Reservoir Quadrangle, Yuma County, Arizona and Imperial County, California, Arizona Geologic Survey Open-File Report 92-11, October 1992.

U.S. Department of Transportation, Federal Highway Administration, Project Development and

Design Manual (PDDM), Chapter 11 – Pavements, Government Printing Office, Washington

D.C, March 2008, December 2014 transmittal.

U.S. Department of Transportation, Federal Highway Administration, Standard Specifications for

Construction of Roads and Bridges on Federal Highway Projects FP-14, U.S.

Yeh and Associates, Inc. (2015), Geotechnical Field Investigation Plan for Martinez Lake Road, AZ FLAP 439(1), Yuma County, Arizona, memorandum prepared for Jacobs Engineering

Group, Inc., YA Project No. 214-248, submitted December 16, 2015.

Yeh and Associates, Inc. (2016), Geotechnical Field Investigation Summary for Martinez Lake

Road, AZ FLAP 439(1), Yuma County, Arizona, memorandum prepared for Jacobs

Engineering Group, Inc., YA Project No. 214-248, submitted January 20, 2016

Yeh and Associates, Inc., Preliminary Pavement Structural Sections for Martinez Lake Road 4R, MP4.3-10.2, AZ FLAP 439(1), Yuma County, Arizona, memorandum prepared for Jacobs

Engineering Group, YA Project No. 214-248, submitted February 8, 2016.

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1300+00

1250+00

1200+00

1150+00

1100+00

1050+00

End Station 1322+00

Begin Station 1011+00

Martinez Lake Road

16P24

16P-25

16P-23

16P-22 16P-21

16P-20 16P-19

16P-18 16P-17

16P-16 16P-15

16P-14

16P-12

16P-11

16P-10

16P-09

16P-08 16P-0716P-05

16P-04 16P-0216P-01

16B-05

16B-04 16B-03

16B-02

16P-13

16P-06 16P-03

16B-01

Content may not reflect National Geographic's current map policy. Sources:

National Geographic, Esri, DeLorme, HERE, UNEP-WCMC, USGS, NASA, ESA, METI, NRCAN, GEBCO, NOAA, increment P Corp.

Boring Location Map

PROJECT NAME: PLATE

PROJECT NUMBER: DATE:

0 10.5

Miles

214-248 2016

MARTINEZ LAKE ROAD

Yuma County, AZ

Yuma Proving Grounds to Highway 95

PLATEPROJECT NAME:

PROJECT NUMBER: DATE:

DRILL HOLE DIAGRAM

Qa1

Qa2

LEGEND:

Alluvium: Loose SAND with clay (SW-SC) and trace gravel.

Interpreted Groundwater Surface

Groundwater Level Encountered

ASTM D2487/USCS CLASSIFICATION SYMBOLS:

SP, SW

GP, GW

SM, GM

SC, GC

CL, CH

ML

poorly graded, well graded SAND poorly graded, well graded GRAVEL silty SAND, silty GRAVEL clayey SAND, clayey GRAVEL lean CLAY, fat CLAY

SILT

DUAL SYMBOLS REPRESENT MIXED OR

BORDERLINE SOIL CLASSIFICATIONS

SEE TEXT AND LOGS OF EXPLORATION FOR

DESCRIPTION OF SUBSURFACE CONDITIONS

Alluvium: Medium dense SAND with clay (SW-SC) and trace gravel.

Qa3 Alluvium: SAND with clay and gravel (SP-SC).

Ground Surface

Qa1

Qa2

Qa3

1014+00

A’

1014+20 1014+40 1014+60 1014+80 1015+00 1015+201013+80 1015+40

-20

A

-10

-30

-20

-10

-30

0 20

SCALE 2a Martinez Lake Road Yuma County, AZ

214-248 2016

Box Culvert 1, Sta. 1014+55

Nort h

16B-01

DRILL HOLE DIAGRAM

LEGEND:

Interpreted Groundwater Surface

Groundwater Level Encountered

ASTM D2487/USCS CLASSIFICATION SYMBOLS:

SP, SW

GP, GW

SM, GM

SC, GC

CL, CH

ML

poorly graded, well graded SAND poorly graded, well graded GRAVEL silty SAND, silty GRAVEL clayey SAND, clayey GRAVEL lean CLAY, fat CLAY

SILT

DUAL SYMBOLS REPRESENT MIXED OR

BORDERLINE SOIL CLASSIFICATIONS

SEE TEXT AND LOGS OF EXPLORATION FOR

DESCRIPTION OF SUBSURFACE CONDITIONS

Ground Surface

1115+80

A’

1116+00 1116+20 1116+40 1116+60 1116+80 1117+001115+60 1117+20

-20

A

-10

-30

-20

-10

-30

0 20

SCALE 2b Martinez Lake Road Yuma County, AZ

214-248 March 2016

Box Culvert 2, Sta. 1116+42

No rth

16B-02

DRILL HOLE DIAGRAM

LEGEND:

Interpreted Groundwater Surface

Groundwater Level Encountered

ASTM D2487/USCS CLASSIFICATION SYMBOLS:

SP, SW

GP, GW

SM, GM

SC, GC

CL, CH

ML

poorly graded, well graded SAND poorly graded, well graded GRAVEL silty SAND, silty GRAVEL clayey SAND, clayey GRAVEL lean CLAY, fat CLAY

SILT

DUAL SYMBOLS REPRESENT MIXED OR

BORDERLINE SOIL CLASSIFICATIONS

SEE TEXT AND LOGS OF EXPLORATION FOR

DESCRIPTION OF SUBSURFACE CONDITIONS

Ground Surface

1126+00

A’

1126+20 1126+40 1126+60 1126+80 1127+00 1127+201125+80 1127+60

-20

A

-10

-30

-20

-10

-30

1127+40

0 20

SCALE 2c Martinez Lake Road Yuma County, AZ

214-248 2016

Box Culvert 3, Sta. 1126+80

No

16B-03

DRILL HOLE DIAGRAM

LEGEND:

Interpreted Groundwater Surface

Groundwater Level Encountered

ASTM D2487/USCS CLASSIFICATION SYMBOLS:

SP, SW

GP, GW

SM, GM

SC, GC

CL, CH

ML

poorly graded, well graded SAND poorly graded, well graded GRAVEL silty SAND, silty GRAVEL clayey SAND, clayey GRAVEL lean CLAY, fat CLAY

SILT

DUAL SYMBOLS REPRESENT MIXED OR

BORDERLINE SOIL CLASSIFICATIONS

SEE TEXT AND LOGS OF EXPLORATION FOR

DESCRIPTION OF SUBSURFACE CONDITIONS

Ground Surface

1128+00

A’

1128+20 1128+40 1128+60 1128+80 1129+00 1129+201127+80 1129+60

-20

A

-10

-30

-20

-10

-30

1129+40 1129+80

0 20

SCALE 2d Martinez Lake Road Yuma County, AZ

214-248 2016

Box Culvert 4, Sta. 1128+75

No rt h

16B-04

DRILL HOLE DIAGRAM

LEGEND:

Interpreted Groundwater Surface

Groundwater Level Encountered

ASTM D2487/USCS CLASSIFICATION SYMBOLS:

SP, SW

GP, GW

SM, GM

SC, GC

CL, CH

ML

poorly graded, well graded SAND poorly graded, well graded GRAVEL silty SAND, silty GRAVEL clayey SAND, clayey GRAVEL lean CLAY, fat CLAY

SILT

DUAL SYMBOLS REPRESENT MIXED OR

BORDERLINE SOIL CLASSIFICATIONS

SEE TEXT AND LOGS OF EXPLORATION FOR

DESCRIPTION OF SUBSURFACE CONDITIONS

Ground Surface

1165+20

A’

1165+40 1165+60 1165+80 1166+00 1166+20 1166+401165+00 1166+80

-20

A

-10

-30

-20

-10

-30

1166+60 1167+201167+00

0 20

SCALE 2e Martinez Lake Road Yuma County, AZ

214-248 2016

Box Culvert 5, Sta. 1166+05

St a.

6+

No

16B-05

APPENDIX A - BORING LOGS

DATE

10/28/2016

PROJECT NAME

Martinez Lake Road

SANDY ORGANIC fat CLAY with GRAVEL GRAVELLY ORGANIC fat CLAY GRAVELLY ORGANIC fat CLAY with SAND

Elastic SILT

ORGANIC elastic SILT with GRAVEL

SANDY elastic ELASTIC SILT

SILTY, CLAYEY SAND

Group Names

SC-SM

Graphic / Symbol Graphic / Symbol Group Names

GC

GP

GC-GM

SANDY ORGANIC SILT

Lean CLAY with SAND Lean CLAY with GRAVEL

SANDY lean CLAY with GRAVEL

ORGANIC lean CLAY

GRAVELLY ORGANIC lean CLAY GRAVELLY ORGANIC lean CLAY with SAND

Fat CLAY

Elastic SILT with GRAVEL

SANDY elastic SILT SANDY elastic SILT with GRAVEL GRAVELLY elastic SILT GRAVELLY elastic SILT with SAND

ORGANIC elastic SILT

SANDY ORGANIC SILT with GRAVEL

GRAVELLY ORGANIC SILT

GRAVELLY ORGANIC SILT with SAND

ORGANIC SILT

Well-graded SAND with CLAY and GRAVEL (or SILTY CLAY and GRAVEL)

SILTY, CLAYEY SAND with GRAVEL

CLAYEY SAND with GRAVEL

SILTY SAND with GRAVEL

COBBLES

Well-graded GRAVEL with SAND

Well-graded GRAVEL with SILT

Well-graded GRAVEL with CLAY and SAND (or SILTY CLAY and SAND)

Well-graded SAND with CLAY (or SILTY CLAY)

Poorly graded GRAVEL

Poorly graded GRAVEL with CLAY (or SILTY CLAY)

Poorly graded SAND with SILT

Poorly graded SAND with CLAY (or SILTY CLAY)

Poorly graded SAND with CLAY and GRAVEL (or SILTY CLAY and GRAVEL)

Lean CLAY

ORGANIC elastic SILT with SAND

SANDY ORGANIC elastic SILT with GRAVEL GRAVELLY ORGANIC elastic SILT GRAVELLY ORGANIC elastic SILT with SAND

GW-GC

GP-GM

GP-GC

GM

Well-graded SAND with SILT

SW-SC

SP-SM

GRAVELLY SILT

Modified California Sampler (3" O.D.)

GRAVELLY SILT with SAND

SILT

ORGANIC SILT with SAND ORGANIC SILT with GRAVEL

Standard Penetration Test (SPT) (2" O.D.)

GROUP SYMBOLS AND NAMES

DRILLING METHOD SYMBOLS

OL

CH

MH

OH

OL/OH

ORGANIC SOIL

ORGANIC SOIL with SAND ORGANIC SOIL with GRAVEL

SANDY ORGANIC SOIL

SANDY ORGANIC SOIL with GRAVEL

GRAVELLY ORGANIC SOIL

GRAVELLY ORGANIC SOIL with SAND

OH

SM

Poorly graded SAND with SILT and GRAVEL

SANDY lean CLAY

GRAVELLY lean CLAY

ORGANIC lean CLAY with SAND ORGANIC lean CLAY with GRAVEL

SANDY ORGANIC lean CLAY SANDY ORGANIC lean CLAY with GRAVEL

Fat CLAY with SAND Fat CLAY with GRAVEL

SANDY fat CLAY SANDY fat CLAY with GRAVEL GRAVELLY fat CLAY GRAVELLY fat CLAY with SAND

ORGANIC fat CLAY ORGANIC fat CLAY with SAND ORGANIC fat CLAY with GRAVEL

SANDY ORGANIC fat CLAY

Elastic SILT with SAND

Well-graded GRAVEL

Poorly graded GRAVEL with SILT

GRAVELLY lean CLAY with SAND

Standard California Sampler (2.5" O.D.)

C Consolidation (ASTM D 2435-04)

CL Collapse…