The Department of Homeland Security proposed Wednesday requiring colleges to pay $70,000 for each international student applying for Optional Practical Training, a sharp increase from the roughly $500 fee students have generally paid themselves. The proposal would also charge schools $30,000 for applications to extend the program. Optional Practical Training, or OPT, allows students on F-1 visas to work temporarily in the United States in jobs related to their fields of study after graduation. The program is an important factor in international students’ decisions to study in the United States and can provide a path to other immigration statuses, including the H-1B visa, for graduates seeking to remain in the country for work. Shifting the fee to colleges—and raising it dramatically—could make the cost of supporting OPT applicants a significant consideration for schools. DHS defended the proposal as a way to limit what it characterized as unfair competition with U.S. workers. An unnamed department spokesperson said OPT was not intended to serve as a “back door into the American workforce” or a source of low-cost labor, and said foreign students should demonstrate their value to employers.