Tennessee will reduce speeds in Sullivan County to decrease air-polluting emissions. The affected area includes Interstate 81 from Kingsport to Bristol on the Virginia border, as well as portions of U.S. 421 toward Mountain City and U.S. 23 toward Asheville, N.C.
State transportation workers hoped to begin posting the new signs Feb. 5. The speed limit will be decreased from 70 mph for all vehicles to 55 mph for trucks and 65 mph for other vehicles. The Highway Patrol will issue only warnings the first two weeks.
The U.S. Environmental Protection Agency considers Sullivan County a “non-attainment area” because of air pollution, says Ed Cole, environmental and planning chief for Tennessee’s transportation department.
“County governments are looking at ways to improve air quality to meet EPA standards,” Cole says. “A study conducted by the Federal Highway Administration shows that reducing truck speed limits by 10 mph can reduce the nitrogen oxide emissions factor by about 18 percent or more per truck. If we get reductions anywhere close to that level, it will be worth it.”