The Comptroller shall administer and enforce this title. The Comptroller may delegate any power or duty of the Comptroller under this title. To enforce this title, the Comptroller may make investigations, hold hearings, examine persons under oath, and receive evidence. To enforce this title, the Comptroller may issue subpoenas for the attendance of witnesses to testify or to produce evidence. For inspection or drawing samples, the Comptroller shall have access, during normal business hours, to: each place where motor fuel is stored for sale; each conveyance used to transport motor fuel; or subject to the provisions of paragraph (2) of this subsection, the propulsion tank of any special fuel powered motor vehicle used for business purposes. In the case of the propulsion tank of a vehicle described in paragraph (1)(iii) of this subsection, the Comptroller shall also have access for inspection or drawing samples any time the vehicle is in operation. A denial of access by an agent, owner, or other person who operates such a place, conveyance, or motor vehicle is prima facie evidence of a violation of this title. The Comptroller may detain a motor vehicle, vessel or railroad tank car placed on a customer’s siding for use or storage for the purpose of inspecting the vehicle’s propulsion tanks. The Comptroller may remove samples of diesel fuel in reasonable quantities necessary to determine the composition of the fuel. The Comptroller may inspect and issue citations to operators of motor vehicles for violations of this subtitle at sites where fuel is, or may be, produced, stored, or loaded into or consumed by motor vehicles including: a terminal; a fuel storage facility or bulk storage facility that is not a terminal; a retail fuel facility; a highway rest stop; and a highway inspection station, weigh station, mobile inspection station, or other similar location designated by the Comptroller.