A biofilm is a congregation of single or various organismal populations that are attached to either an abiotic or biotic surface through a self-secreted material called extracellular polymeric substance (EPS). Bioremediation is a safe, ecologically sustainable alternative to chemical and physical methods of environmental remediation. One preferred method of in-situ bioremediation is biofilm technology because pollutant-degrading organisms are able to survive and adapt better to environmental conditions within their EPS barriers. In our lab we are using single organism, Pseudomonas sp. strain ADP biofilms, attached to glass slides in a drip flow reactor (DFR) being fed 50- ppm atrazine solution. We are comparing this data to the same P. ADP cells under planktonic conditions in a liquid media shake flask. Our pollutant of interest is atrazine (C 8 H 14 N 5 Cl), a herbicide that has been widely used on farms in the United States since 1958 to kill weeds. Atrazine is created under laboratory conditions and does not occur naturally. In our experiment, we are expecting to observe some atrazine degradation in shake flasks and a higher level of degradation under DFR conditions. We collected samples daily from the shake flask as well as the effluent from the DFR, to be processed with liquid-liquid extraction for GC-MS analysis to quantify levels of atrazine degradation.