During the period from 1993 to 1996, a long-term program was initiated to conduct remediation research at the Strachan Gas Plant in Alberta, Canada. As part of this research program, optimization of the existing pump-and-treat (P{ampersand}T) facility was of interest. The cost-effective treatment of contaminated groundwater produced from the P{ampersand}T system was complicated by several factors, including: (1) increased cost and reduced effectiveness of most water treatment processes because of the cold temperatures and severe winter conditions prevalent in Alberta, (2) interference caused by the mixture of inorganic and organic contaminants found in the groundwater that can reduce the effectiveness of many water treatment processes, and (3) pretreatment to prevent scaling in existing treatment process unit operations caused by the iron, manganese, and hardness of the contaminated groundwater.