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Wild Horse Dams and Reservoir West Test Quarry DRMS 111 Application
<br /> For the proposed Wild Horse Reservoir,the dams will likely be either earth-or rockfill embankments.The core will
<br /> be composed of fine-grained on-site borrow material. The upstream and downstream shells will be composed of
<br /> earth or rockfill. A two-layer chimney filter/drain system is required, consisting of a coarse filter (drain) layer
<br /> downstream of a fine filter layer, will be included between the core and the downstream shell. The minimum
<br /> horizontal widths of the filter zones will be 5 feet for each zone. A two-layer blanket drain will connect the
<br /> downstream chimney drain to the downstream toe. The filter drain system is required to evacuate water seeping
<br /> through the dam. Large-size rock will also be required as riprap for erosion protection on the upstream slope to
<br /> protect against wave and wind action. A 3-foot layer of riprap bedding may be required to protect the underlying
<br /> embankment from scouring. A summary of showing Project material requirements for a select dam type scenario
<br /> is presented in Table 3-3.
<br /> Table 3-3: Summary of Total Rough Order of Magnitude Material Quantities
<br /> for Selected Dam Type Scenario
<br /> Core Material ASTM C-33 1-1/2"- 6"-Bedding/ Shell
<br /> Dso = 30"
<br /> Dam Dam Type (Low- Washed Gravel 3"- Material Riprap
<br /> Permeability Filter Sand Drain Transition (Rockfill/Eart (CY)
<br /> Fine-Grain)(CY) (CY) (CY) (CY) hfill) (CY)
<br /> Zone 1 Zone 2 j Zone 3 Zone 6/3A Zone 4 Zone 7
<br /> West Dam Earthfill 1,615,000 345,000 335,000 235,000 5,345,000 380,000
<br /> East Dams Earthfill 100,000 35,000 30,000 11 30,000 370,000 50,000
<br /> Main Dam Rockfill 290,000 45,000 45,000 19,000 775,000 55,000
<br /> Total 2,005,000 425,000 410,000 285,000 6,490,000 485,000
<br /> (Values over 20,000 rounded up to next 5,000;values under 20,000 rounded up to next 1,000.)
<br /> Wild Horse Reservoir is a large-scale civil construction project with several appurtenances, including structures,
<br /> roads, and pipelines. Rock-sourced material is required for road base, coarse and fine aggregates, and pipe
<br /> bedding material.Any material that can be produced to suitable quality and quantity on-site reduces the need for
<br /> import, thus making the project more economically feasible and minimizing hauling.
<br /> 3.2.15 Explosives
<br /> 6.3.3(p)Specify if explosives will be used in conjunction with the mining or reclamation operation. In consultation
<br /> with the Office, the Applicant must demonstrate,pursuant to Rule 6.5(4), Geotechnical Stability Exhibit, that off-
<br /> site areas will not be adversely affected by blasting during mining or reclamation operations.
<br /> Drilling will be accomplished with hydraulic track-mounted drills. Material is planned to be extracted for this
<br /> program via blasting. It may be necessary to remove overburden material in order to reach rock of suitable quality
<br /> for drilling and blasting.
<br /> The quarry surface will be made level based on the geology of the rock surface and the initial blast. As blasting
<br /> continues, each quarry will typically develop a more level blasting surface for subsequent blasts. Drilling will be in
<br /> a specified pattern and to a specified depth for each blast. Blasting will be divided into smaller blasts and
<br /> sequenced from the free face in a top-down manner. The blasting plan will begin with a series of test blasts to
<br /> determine the optimum blast design.
<br /> Explosives such as Ammonium Nitrate mixed with Fuel Oil (ANFO) or equivalent blasting emulsions consisting of
<br /> oxidizers,fuels,and stabilizers will be used as the explosive agent. Explosives will be delivered to the site as needed;
<br /> no explosives will be stored on-site. Precise quantities of the explosive agent will be added to each drill hole to
<br /> achieve a certain powder factor that varies based on the density of the rock being blasted and based on the
<br /> intended rock product. Blasting will be done with modern detonation methods to achieve millisecond delays
<br /> Tetra Tech May 2024 17
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