(a) The board of regents of the Texas State University System may charge each student enrolled at Southwest Texas State University an environmental service fee in an initial amount not to exceed $1 per semester of the regular term or term of the summer session. The fee may not be imposed unless approved by a majority vote of the students at the university voting in an election held for that purpose at the same time and using the same ballot as a student government election.
(b) Not more than once in an academic year, the board of regents may increase the amount of the fee authorized by this section to cover increased operating costs of environmental services funded from revenue from the fee. The board may not increase the amount of the fee unless the increase is approved by a majority vote of the students at the university voting in an election held for that purpose in which at least 1,000 students at the university cast ballots and that is held at the same time and using the same ballot as a student government election. The total amount of the increased fee may not exceed:
(1) $6 per student for each regular semester or for each term of the summer session not covered by Subdivision (2); or
(2) $3 per student for each six-week or shorter term of the summer session.

(c) A fee imposed under this section may be used only to provide environmental improvements at the university through services such as recycling, transportation, employment, product purchasing, matching funds for grants, planning and maintenance, and irrigation.
(d) The university may not use revenue from the fee imposed under this section to reduce or replace other money allocated by the university for environmental projects.
(e) The university shall retain any fee revenue that exceeds the amount necessary to cover current operating expenses for environmental services and any interest generated from that revenue. The university may use the excess revenue and interest generated from that revenue only for the purposes provided by Subsection (c).