I applied online. The process took 4 weeks. I interviewed at Oklahoma Department of Environmental Quality (Oklahoma City, OK) in Jun 2015
Interview
First, I had taken a 45 min. grammar and writing test, which had high relate to the job responsibility. After the writing test, there was a 45 min Panel Interview. They asked 10 questions and score them. At last, you can ask any question which you concern about the job. They are very friendly to solve the problem for you.