DA Smith was commissioned in 2020 by the Federal Highway Administration (FHWA), Central Federal Lands Highway Division to conduct exploratory drilling on the existing Upper and Lower Kings River highway bridges located in Kings Canyon National Park, Highway 180, California. ODEX drilling was required through the sand and granite boulder sediments comprising the Kings River channel for the purpose of evaluating a deep foundation refitting option.
A total of 1,154 feet was drilled in 11 holes, with the deepest hole reaching 115 feet. Holes were drilled through the both the bridge deck and roadway abutments. SPT sampling was conducted on 5-foot intervals. Downhole flowing sands required the use of a special cuttings capture and diversion system to avoid sediment contamination in the river. DA Smith controlled highway traffic while drilling with an automated traffic signal system. Careful coordination with the FHWA, National Park Service, and regional vendors allowed logistical challenges posed by the site’s remote mountain location to be overcome, resulting in a successful and efficient drilling campaign.
DA Smith has and continues to drill for multiple client firms on the Western Slope, including the Federal Highway Administration (FHWA), CTL Thompson, DOWL, Cesare Inc., CGRS, RockSol, Walter Environmental & Engineering Group, Lithos Engineering, Gerhart Cole, Snowshoe Engineering, Ninyo and Moore, Lincoln-Devore, and others. Projects include disturbed and undisturbed soil sampling, standard penetration testing, GeoProbe direct push sampling, ODEX drilling, mud rotary drilling, bedrock coring, contaminant sampling, water sampling and monitoring wells, and piezometer installations. Sites range from drive-up to difficult-access locations on public and private property.
In 2018, DA Smith (formerly Agapito Associates, Inc.) drilled one test well and two associated monitoring wells near the U.S. National Park Service’s Phantom Ranch located at the bottom of the Grand Canyon. Drilling was completed under contract to HDR Engineering, Inc. in support of a larger study to develop alternate water supplies for National Park Service facilities at the Grand Canyon. AAI’s crew, supplies, fuel, and heli-portable drilling equipment was airlifted to site via helicopter. Crews resided on site for the duration of the drilling campaign.
Work activities were carefully coordinated with NPS personnel to minimize ground disturbance and impacts to tourists, including tourists traveling via mule train past the drill site. One 8-inch diameter test well (4-inch casing) and two 6-inch diameter monitoring wells (2-inch casing) were drilled through unconsolidated gravel and boulders to depths reaching 50 feet.
The test well was completed with steel casing and screen, a test pump, and wellhead piping containing a flow meter, pressure gauge, isolation valve, and a stainless steel sampling tap. A 4-hour step drawdown test, followed by a 24-hour constant rate pumping test was conducted by DA Smith personnel under the supervision of an HDR hydrogeologist.
In 2017, DA Smith (formerly Agapito Associates, Inc.) drilled monitoring wells into and near the Level 2 Adit of the Standard Mine located near Crested Butte, Colorado, for HDR Engineering, Inc. in support of the Environmental Protection Agency’s (EPA) remediation work at the Standard Mine Superfund Site, located in the Gunnison National Forest.
Drilling was completed with a low-impact, track-mounted drill rig and down-the-hole (DTH) hammer. DA Smith modified a specialized light rig for the remote alpine site conditions located above 11,000 feet. Holes were drilled to 85 feet deep. The wells were completed with 5.0-inch-diameter, Schedule 80 pipe, grouted with bentonite, and capped. A monument with a locking cap and protective bollards were installed.
In 2020, DA Smith drilled 12 ODEX holes to sample sand and gravel resources to a depth of 54 feet for Rocky Mountain Industrials (formerly Rocky Mountain Resources). Holes were logged and continuously sampled over their length with 3.5-foot intact tube samples or 5-foot bulk bucket samples.