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SITE CONDITIONS At the time of this investigatio4 the majority of the subject roadways were surfaced with highly variable amounts of granular road base. The roadway surfaces generally appeazed to be in poor to good condition and the majority of the roadway subgrade materials appeared stable at the time this report was prepared. It is our understanding that the roadway surface conditions deteriorate rapidly when they become saturated. The existing roadways generally had been constructed with drainage/borrow ditches along both shoulders. A majority of the ditchlines appeaz to be removing the surface runoff away from the roadways adequately; however, we did observe a number of areas where the ditches were not adequately removing the runoff away from the roadway sections. FIELD INVESTIGATION The field investigation For this project was conducted from September 13, 1995 to October 5, 1995. Tweary six (7b) shallow test holes were advanced along the subject roadways to explore the existing pavement and subgrade conditions, and to obtain samples for laboratory testing. The test holes were either drilled with atrack-mounted drill rig utilizing 6-inch diameter augers or with a rubber tine backhoe. The test holes were advanced to depths ranging from 3 to 4 fee[. The test holes were logged by a representative of Northwest Colorado Consultants, Inc. Graphic logs of the test holes were not drawn; however, a table indicating the location, road base gravel thickness and subgrade soil types encountered in each hole are presented later in the Subsurface Conditions section of this report. LABORATORY INVESTIGATION Samples obtained from the test holes were examined and classified in [he laboratory by the project en¢~'aeer. Laboratory testing included standazd property tests, such as natural moisture contents, dry unit weights, grain size analyses and liquid and plastic limits. The laboratory testing was conducted in general accordance with applicable ASTM and AASHTO specifications. Results of the laboratory testing program aze summarized in Table 1. SUBSURFACE CONDITIONS The subsurface conditions encountered in the test holes were highly variable and generally consisted of a layer of granular road base overlying clays and silts. The grantdaz road base materials were encountered at the surface of all [he test holes drilled in the existing roadways. However, natural topsoil was encountered a[ the ground surface along the proposed roadway alignments. The depth and consistency of the road base materials were highly variable across the existing roadways. The depth of the road base materials ranged from as little as 3 inrbes along the SW Bleeder Shaft Access Road to as much as 21 inches along Haul Road B. The consistency of the road base materials was also highly variable. The road base materiak encountered along the southern half of [he Pond A Access Road consisted of gravelly sandy clays which classified as CL soils in accordance with the Uailied Soil Classification System. However, [he road base materials encountered in the Magazine and lob ~o. 95-2431 `lortbwest Colorado Consultants. Inc. Page