Page 227 - Villas at Savona Close-out Manual

Geotechnical Investigation Report
Villas at Savona
continuously examined, visually classified and logged by an Amec Foster Wheeler field geologist.
Results of the field study are presented in Appendix A, which includes a brief description of drilling
and sampling equipment and procedures, and logs of the test borings.

The boring logs and related information included in this report are indicators of subsurface
conditions only at the specific locations and times noted. Subsurface conditions, including
groundwater levels, at other locations on the subject site may differ significantly from conditions
at the sampling locations.

The soils encountered during the field study were visually classified in general accordance with
the Unified Soil Classification System (USCS). The soil classification symbols appear on the
boring logs and are described in Appendix A.

4.2 Laboratory Testing

Laboratory testing was completed to aid in soil classification and evaluation of the engineering
properties of the soil. Selected soil samples were tested for moisture content (ASTM D2216),
Atterberg limits (plasticity index) (ASTM D4318), and particle size distribution (ASTM C136). The
results of the moisture content tests are shown on the boring logs presented in Appendix A. All
other test results are presented in Appendix B.

5.0 SITE CONDITIONS AND GEOTECHNICAL PROFILE

5.1 Site Conditions

The project site is residential complex comprised of 15 buildings along with a swimming pool and
moderate growth of shrubs and trees. The buildings are two-story structures constructed of wood
and stucco and concrete slab-on-grade. Foundations consist of concrete turndowns at the
building edge or shallow spread-type footings founded 1.5 feet below finished grade.

5.2 Geotechnical Profile

The geotechnical profile for soils encountered at the project can be characterized as primarily
clayey sand with occasional lenses of sandy clay. At the surface, exploratory borings encountered
a thin layer of landscape gravel. The Amec Foster Wheeler investigation encountered clayey
sand from the ground surface to the boring termination depth of 20 feet below ground surface.
The TerraPacific investigation indicates clayey sand to a depth of 40 feet. The clayey sand and
sandy clay layers are generally moist, uncemented to strongly cemented, medium plastic, and
light brown to dark brown. Zones of calcium carbonate filaments were visible in soil samples
collected throughout the full depth. In general, SPT blow counts increased with depth with
firmness ranging from soft to hard in the upper ten feet and very firm to hard below 10 feet.
Refusal blow counts were encountered during the geotechnical investigation in boring B-2 and
B-3 at depths of seven and nine feet, respectively.

5.3 Groundwater Conditions

No free groundwater was encountered in the test borings for the investigation or observed during
the site visit. Groundwater depth information available from the Arizona Department of Water

Heerup Engineering, PC
Chandler, Arizona December 30, 2015 Page 2