Boart Longyear diamond drilling firm; Brainard-Kilman, a maker of civil engineering devices, such as well monitoring and test equipment; and ChemGrout a mfg of cement grouting equipment. Longyear acquired Slope Indicator Company, the nation's largest producer of geotechnical instruments, and Northern Air Supply in 1988, followed by the Campbell Pacific Division in 1989 and WTD Environmental Drilling in 1990. Then in 1994, North Star Drilling Company, specializing in sonic drilling was acquired. On January 2, 1995, Boart International and the Longyear Company officially merged into a single company and changed its name to Boart Longyear Limited. At this point the two companies
Waste-to-energy plant plants are located in industrial areas. Landfill gas, which contains about 50% methane, and 50% carbon dioxide, is contaminated with a small amount of pollutants. Unlike at waste-to-energy plants, there are little or no pollution controls on the burning of landfill gas. The gas is usually flared or used to run a reciprocating engine or microturbine, especially in digester gas power plants. Cleaning up the landfill gas is usually not cost effective because natural gas, which it substitutes for, is relatively cheap. Waste-to-energy plant A waste-to-energy plant is a waste management facility that combusts wastes to produce electricity. This type