Permits must be acquired from the U.S. Army Corps of Engineers and the state's Division of Water Quality for any impacts to wetlands or streams. The Natural Systems Group is responsible for obtaining these permits and developing the mitigation plans, which are often required as a condition of the permits. Construction cannot go ahead until all permits are acquired and mitigation plans are approved. Engineers in the Special Environmental Analyses Unit study air quality and noise impacts of highway projects. Staff in the Air Quality and Noise Analysis unit use field data and simulation models to determine potential impacts.
Staff also study air quality in the vicinity of highway projects.
This ensures that the improvements will not adversely effect air quality. Sometimes projects that relieve congestion will actually improve air quality in the immediate area. Community impacts are also studied in the Special Environmental Analyses Unit. A community impacts assessment is conducted in conjunction with environmental impact studies to evaluate the effects of a transportation project on a community and its quality of life. This process is an integral part of project development, assisting in avoiding, minimizing or mitigating impacts.