Terracon Share: DrillingEngineering & ConsultingTesting Services Terracon Visit Website 514 Hillcrest Industrial Blvd. Macon, GA 31204 (478) 757-1606 (478) 757-1608 (fax) LinkedIn Hours: 7:30 am - 5:00 pm About Map About Geotechnical & Environmental Consultants, Inc. (GEC) is a leading statewide provider of comprehensive geotechnical and environmental consulting and construction quality control testing services. What's Nearby? Distance: 5 10 15 20 25 50 mi.