The doctor of philosophy (Ph.D.) degree program is a research-oriented degree intended for full-time students. Although courses may be taken on a part-time basis, a minimum of one year of full-time residency normally is required for completion of the doctoral dissertation.
Admission and Degree Requirements for Students Entering with a Master's Degree
A master's degree in geology, chemistry, biology, chemical engineering, environmental engineering, environmental science, or related fields usually is required. In some cases, highly qualified students with bachelor's degrees in these fields may be accepted directly into the doctoral program.
A minimum master's grade-point average (GPA) of 3.5, or the equivalent, typically is required for admission, and applicants must submit their GRE scores. International students must achieve a minimum TOEFL score of 550.
Specific degree requirements and dissertation topics are approved by the department on an individual basis. Among the requirements, students must:
1. maintain a minimum overall GPA of 3.0;
2. take a minimum of 30 credits of EvSc 790 or 26:375:790 Doctoral Dissertation;
3. have completed at least 18 credits of formal elective coursework beyond the master's degree.
If a student should complete the required 30 credits of EvSc 790 or
26:375:790 before the dissertation research is completed, he or she
must register for a minimum of 3 credits of EvSc 790 or 26:375:790 for
each semester until the dissertation research has been completed. Students who have completed their research and are only writing their dissertation must register matriculation continued (26:380:800) (1H) each semester until the dissertation is completed and submitted.
Admission and Degree Requirements for Students Entering with a Bachelor's Degree
Exceptional students with appropriate undergraduate degrees may apply directly for admission to the doctoral program. Applicants are evaluated on a case-by-case basis. Typically, a minimum undergraduate GPA of 3.5, or the equivalent, is required for admission, and these students must submit their GRE scores. International students must achieve a minimum TOEFL score of 550 on the written test or 213 on the computer test.
Once admitted to the program, students must maintain a minimum overall GPA of 3.0.
Required Courses (30 credits)
Students are required to take a minimum of 30 credits of EvSc 790 or 26:375:790 Doctoral Dissertation.
Electives Courses (30 credits)
No more than 6 credits may be taken in EvSc 725,726 or 26:375:725,726 Independent Study. The remaining 24 credits of electives may be chosen from any 600- to 700-level courses, including courses that are outside the approved course offerings when the approval of the graduate director is obtained. The research adviser will determine the elective courses in consultation with the doctoral student.
All Doctoral Students
Qualifying Examination. Within three semesters of their admission to the program, doctoral students must take a qualifying examination, and they must pass this examination within two years after their admission. A student is allowed only two attempts to pass this examination.
Formation of Dissertation Committee. By the end of second semester, doctoral students must form a dissertation committee that meets the approval of the graduate adviser (not the dissertation adviser) in environmental science. The committee must consist of the doctoral student's dissertation adviser and three additional experts in the field. At least one external committee member is strongly encouraged.
Research Proposal. Within four semesters of admission, each doctoral student must make a formal oral and written presentation on the scope of his or her proposed research to members of this committee and to other interested persons. The committee members must approve formally the dissertation proposal by the end of the fourth semester. This time frame ensures that students meet the doctoral requirement of having an approved dissertation committee formed and a dissertation proposal approved within one semester of passing the qualifying examination.
Dissertation. The dissertation must be composed at a minimum of three papers submitted to an appropriate peer-reviewed journal in the field of study. These papers must be substantiated with appropriate introduction and summary chapters. Doctoral students must, at a minimum, meet the following requirement before being approved to advance to the dissertation defense: one paper published, one paper accepted for publication and one paper submitted for possible publication.
Dissertation Defense. After submitting the final document to the dissertation committee, students are required to make an oral defense of their dissertations. To receive final approval, students must obtain signatures from all members of the dissertation committee. Any student who is unable to complete the requirements for the Ph.D. degree may become a candidate for the master of science in environmental science once he or she meets the requirements for that degree.
Programs, Faculty, and Courses 
