TECHNOLOGY FOCUS - BIOTECHNOLOGY - Preferred Method: The method comprises providing oxygen and butane either at a constant rate or in pulses to (1) for the entire treatment time. Oxygen is provided as air and butane is provided as a butane substrate comprising at least about 10(preferably 50, particularly 90, especially 99) wt.% butane. The pollutant is treated in-situ at the contaminated site or in a reactor. The pollutant is present within the soil, in a gas (preferably air) or liquid (preferably water). (1) degrades the MTBE in water at a rate greater than 0.1 (preferably 0.2) mg/hour/liter. The decontaminated water comprises less than about 70 (preferably 20, particularly 5, especially 1) ppb MTBE.Preferred Genus: (1) comprises at least one bacterium selected from Pseudomonas, Variovorax, Nocardia, Chryseobacterium, Comamonas, Acidovorax, Rhodococcus, Aureobacterium, Micrococcus, Aeromonas, Stenotrophomonas, Sphingobacterium, Shewanella, Phyllobacterium, Clavibacter, Alcaligenes, Gordona, Corynebacterium or Cytophaga. Preferred Species: (1) comprises at least one bacterium selected from putida, rubrisubalbicans, aeruginosa, paradoxus, asteroides, brasiliensis, restricta, globerula, indologenes, meningosepticum, acidovorans, delafieldii, rhodochrous, erythropolis, fascians, barkeri, esteroaromaticum, saperdae, varians, kristinae, caviae, maltophilia, thalpophilum, spiritivorum, putrefaciens B, myrsinacearum , michiganense, xylosoxydans, terrae, aquaticum B or johnsonae. SPECIFIC MICROORGANISMS - Pseudomonas rubrisubalbicans , Pseudomonas aeruginosa , Variovorax paradoxus , Nocardia asteroides , Nocardia restricta , Chryseobacterium indologenes , Comamonas acidovorans , Acidovorax delafieldii , Rhodococcus rhodochrous , Rhodococcus erythropolis , Aureobacterium esteroaromaticum , Aureobacterium saperadae , Micrococcus varians , Micrococcus kristinae , Aeromonas caviae , Stenotrophomonas maltophilia , Sphingobacterium thalpophilum , Clavibacter michiganense , Alcaligenes xylosoxydans , Corynebacterium aquaticum B and Cytophaga johnsonae are specifically claimed as (1).    EXAMPLE - None given.