3702 TULALIP AVE 2016-01-01 MF Import

SERS Pub�ic Safeh ^-1-1 Communication Tower , � SI Report No. 704-05224-5 December 2G, 2000 Page 2 3.1 Subsurface Exploration In order to ascertain soii conditions at the site, three Standard Penetration Test (SP� soil borings (B-1 through B-3) were made using our CME75 truck-mounted, hollow-stem, power auger with an automatic hammer. The soil boring locations were reviewed with Mr. Ottosen and Mr. Diamond prior to drilling and are shown on the attached Boring Location Plan in the Appendix. The boring logs are also found in the Appendix. It shouid be noted that PSI was not able to place soil borings at all proposed guy locations due to lack of access by our drill rig. Portions of the site had not been cleared of trees and dense brush or graded level at the time of our site exploration. The Standard Penetration Test is performed by driving a 2-inch, O.D., split-spoon sampler into the undisturbed formation located at the bottom of the advanced auger with repeated blows of a 140- pound, pin-guided, automatic hammer falling a vertical distance of 30 inches. The number of blows required to drive the sampler one-foot is a measure of the soil consistency (cohesive soils) anc density(non-cohesive soils). The automatic hammer used on our drill rig generally produces lower standard penetration test values than those oblained using a traditional safety hammer. Studies by PSI have generally indicated that penetration resistances may vary by a factor of 1.5 to 2 between the two methods. We have considered this drilling and testing methodology in our evalualion of soii strength and compressibility. Soil samples were generally taken in the boring at 2.5-foot intervals for the firsl 10 feet, and then at 5-foot intervals to the termination depth of the boring. Samples were identified in the field, placed in sealed containers, and transported to the laboratory (or further classiflcation and testing. Undisturbed samples will be retained for 60 days aker submittai of this report and then discarded, uniess notified otherwise in writing. 3.2 Field & Laboratory Testing Selected samples of the subsurface soils encountered were returned to our laboratory for further evaluation to aid in classification of the materials, and to help assess their strength and compressibility r,haracteristics. The laboratory evaluation consisted of visual and textural examinations, moisture content tests, grain size analyses, and Alterberg limits tests. Results of the tests are summarized in the Appendix. 3.3 Engineering Analyses Engineering analyses and recommendations regarding general foundation design including allowable soil bearing pressures, minimum footing depth requirements, and estimates of