This chapter does not apply to:
(1) salaried employees performing duties for which they were trained and hired solely within a federal or state governmental agency;
(2) persons constructing, opening, or closing wells on their own property;
(3) persons constructing, opening, or closing exploration borings;
(4) persons licensed as contractors pursuant to Chapter 11 who drill a borehole for measuring groundwater levels, blasting, or short term dewatering for construction purposes.