A Ground‐Water Tracer Test with Deuterated Compounds for Monitoring In Situ Biodegradation and Retardation of Aromatic Hydrocarbons

Fully deuterated benzene, toluene, p‐xylene, and naphthalene were used with bromide (inert reference) as ground‐water and pollutant tracers inside a BTEX contaminated plume of anoxic ground water in the Swan coastal plain, Western Australia. Besides the determination of local aquifer parameters and retardation coefficients for several organic pollutants within the contaminated site, this natural gradient ground‐water tracer test shows that deuterated organic compounds can be successfully used for in situ determination of natural biodegradation rates of organic pollutants. It suggests that toluene, p‐xylene, and naphthalene, but not benzene, degrade under sulfate‐reducing conditions.