ABSTRACT
THE NATURE OF BACTERIAL GASES The near-surface underground is a diverse habitat for many species of bacteria. Among the mass of rock, soil, and water underground, bacteria may seem imma terial, but over time they can alter their environment in ways that affect under ground construction. Bacteria underground have no direct access to the energy of the sun; most acquire chemical energy by decomposing organic compounds incorporated in sediments. Among the waste products of bacterial decomposition are potentially hazardous amounts of methane, hydrogen sulfide, and carbon di oxide.
