CHAPTER 5QUARRY SUPERVISORThis chapter provides information on the selectionand operations of pits and quarries. It describes basicprinciples of site selection, preparation, and methodsand techniques of developing pits and quarries.QUARRY SUPERVISORRESPONSIBILITIESPit and quarry operations in the Naval ConstructionForce (NCF) are normally managed by Alfa company.The operations chief of Alfa company is usuallyresponsible for the pit and quarry operations andnormally assigns a quarry supervisor to direct theoperations of the pit and quarry.PITS AND QUARRIESThe operation of the pit and quarry is directlydetermined by the material requirements and tasking forconstruction projects and rock crushing operations. Thesize of the crew assigned to support the pit or quarryoperations is dictated by the availability of theequipment and material required for a construction task.Pits and quarries are classified according to the typeof material they contain and the methods used toexcavate and process the material (table 5-1).PitsPits are excavations made at the earth’s surface inunconsolidated materials, such as clay, sand, gravel,coral, and laterite. They are sites from which suitableconstruction materials are obtained in quantity, beingremoved or extracted from the surface without the useof blasting. Alluvial or stream-deposited gravel pitsyield gravel that is usually clean and free of clay andhumus and are therefore desirable for concrete andbituminous work. Bank or hill gravel pits yield a clayeygravel that is desirable for road or runway surfacingbecause of its binding qualities. Gravel is also used forbase courses and fills. Soil (other than sand and gravel)selected for use in embankments, fills, and subgrades isobtained from borrow pits. Miscellaneous pits containmixed tailings, slag, cinders, or the like, which are alsoused for road or runway surfacing and as aggregates.QuarriesQuarries are sites where large, open excavations aremade for the purpose of extracting or removing rock inits natural state by drilling, cutting, and blasting. In somecases, it may be possible to remove and break up rockby use of dozer rippers and bull pricks (jack hammerattachment). The primary types of rocks obtained fromquarries are igneous and metamorphic, such as trap rock,granite, diorite, geneiss, quartize, and certain shales.Military quarries are generally open-faced, whichmeans the vertical surface of the rock is exposed. Sinceseldom used in its inplace state, quarry rock is processedwith mobile equipment that crushes, screens, andwashes.SITE SELECTIONBefore a pit or quarry is located, an investigation ofthe site must be performed to establish that suitableconstruction materials are available in adequateamounts and that the excavation can be workedefficiently with available equipment. Wheneverpossible, existing pits and quarries are used because (1)the quantity and quality of materials can easily bedetermined; (2) good haul and access roads are probablyalready built; (3) less effort can be spent on removal ofoverburden; and (4) facilities, such as ramps, hoppers,bins, power, and water, are generally available.The chosen site should be as close as possible to theconstruction project and convenient to good routes oftransportation. This allows more efficient hauling bydecreasing the length of haul roads. Pit and quarryhaulage is usually accomplished with equipment, suchas dump trucks and scrapers.Soil FormationThe formation of soil is a continuous process.Basically, the crust of the earth consists of rock thatgeologists classify into three groups: igneous, which isformed by cooling from a molten state; sedimentary,formed by the accumulation and cementing of existingparticles and remains of plants and animals; andmetamorphic, formed from existing rocks that havebeen subjected to heat and pressure. When the rock is5-1
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