This chapter applies in Baltimore City and Anne Arundel, Baltimore, Calvert, Carroll, Cecil, Charles, Frederick, Harford, Howard, Montgomery, and Prince George's counties. A gasoline dispensing facility exempted under §C of this regulation is subject only to the record-keeping and reporting requirements of Regulation .07D of this chapter. The provisions of this chapter do not apply to: The owner or operator of an existing gasoline dispensing facility whose average monthly gasoline throughput during calendar years 1990 and 1991 was less than 10,000 gallons; The owner or operator of any new gasoline dispensing facility that has a total gasoline storage tank capacity of less than 2,000 gallons; or An existing independent small business gasoline marketer whose average monthly gasoline throughput during calendar years 1990 and 1991 was less than 50,000 gallons. If a person purchases a gasoline dispensing facility equipped with an approved system, the new owner or operator shall continue to operate the approved system unless the average monthly gasoline throughput during any calendar year after the purchase is less than 10,000 gallons.