Complex sentence: He then worked for LFR Levine Fricke in Emeryville California 1998--2002 as a chemical engineering and environmental consultant in which he designed and implemented wastewater treatment plants using chemical, electrolytic or membrane separation processes.
Split into simpler sentences: He then worked for LFR Levine Fricke in Emeryville California 1998 through 2002 as a chemical engineering and environmental consultant. In this capacity, he designed and implemented wastewater treatment plants using chemical, electrolytic or membrane separation processes.