4-4-7: DRILLING RESTRICTIONS:
   A.   Location: No person, firm or corporation shall conduct any drilling or other oil and gas mining operations within two hundred fifty feet (250') of a residence; provided, that this provision shall not apply to any oil and gas well which was drilled prior to the effective date hereof, and in constant production since the date drilling operations ceased.
   B.   City Permit: No person, firm or corporation shall engage in any oil and gas mining or exploration operation without having first applied for and received from the city a permit for the same. No person, firm or corporation shall engage in mining operations except in compliance with any restrictions imposed by the permit issued by the city. (1991 Code § 14-278)