Applicants accepted into the program must complete at least 30 graduate credit hours to earn a degree. Of these 30 credit hours, 20 must be in courses numbered 500 or above (6 credit hours of thesis plus 14 credit hours of other courses).?ESS 503?must be taken three times during the course of the program, the last of which must be in the student's final semester before graduation. Other specific requirements for the 30 credit hours are listed below.