The Sigma Group (Sigma) is an employee owned, award-winning consulting engineering firm headquartered in Southeastern Wiscons ... in. Sigma provides civil design, environmental consulting, geoscience consulting, and facility services to a diverse range of clients. Our Milwaukee-based staff includes registered Professional Engineers in civil, environmental, and chemical disciplines; Professional Land Surveyors; Construction Inspectors; certified asbestos supervisors/inspectors; certified lead/risk assessors; Certified Hazardous Materials Managers, Professional Geologists, and Registered Hydrogeologists, as well as additional engineering technicians, inspectors, scientists, and compliance specialists. This team of professionals is highly skilled in computer-based applications for modeling and site design, managing GIS-based assets, and environmental information. read more