sary for ingress and egress including the elevated portion thereof used as a hoist, shall be enclosed with fire–resistive soundproofing material approved by the Fire Department, and the same shall be painted or stained so as to render the appearance of said derrick as unobtrusive as practicable. 48. That all tools, pipe and other equipment used in connection with any drilling or production operations shall be screened from view, and all drilling operations shall be conducted or carried on behind a solid fence, which shall be maintained in good condition at all times and be painted or stained so as to render such fence as unobtrusive as practicable. 49. That no materials, equipment, tools or pipe used for either drilling or production operations shall be delivered to or removed from the controlled drilling site except between the hours of 8:00 o’ clock a.m. and 6:00 o clock p.m., on any day, except in case of emergency incident to unforeseen drilling or production operations, and then only when permission in writing has been previously obtained from the Administrator. 50. That no earthen sumps shall be used. 51. That within sixty (60) days after the drilling of each well has been completed, and said well placed on production, or abandoned, the derrick, all boilers and all other drilling equipment shall be entirely removed from the premises unless such derrick and appurtenant equipment is to be used within a reasonable time limit determined by the Administrator for the drilling of another well on the same controlled drilling site. 52. That no oil, gas or other hydrocarbon substances may be produced from any well hereby permitted unless all equipment necessarily incident to such production is completely enclosed within a building, the plans for said building to be approved by the Department of Building and Safety and the Fire Department. This building shall be of a permanent type, of attractive design and constructed in a manner that will eliminate as far as practicable, dust, noise, noxious odors and vibrations or other conditions which are offensive to the senses, and shall be equipped with such devices as are necessary to eliminate the objectionable features mentioned above. The architectural treatment of the exterior of such building shall also be subject to the approval of the Administrator. 53.