D.C. Mun. Regs. tit. 21, r. 21-909
Whenever a septic tank and sub-soil sewage disposal system is discontinued, the system shall be thoroughly and carefully disconnected, the system from the plumbing system and the septic tank shall be filled and covered over in a workmanlike manner.
Whenever any earth pit privy is discontinued, the pit shall be filled in a workmanlike manner as provided in § 907.
Whenever any other privy, outhouse, method or system for storing or disposal of human excreta or body wastes is discontinued, all excreta and body wastes shall be disposed of as provided in this chapter.
All boxes, cans and receptacles used for the reception, storage, or disposal of any human excreta or body wastes from any discontinued privy, outhouse, or other method or system of disposal, shall be disposed of in a manner that does not endanger the public health or otherwise create a nuisance.
The superstructure from any discontinued privy, outhouse, method, or system for storing of disposal of any human excreta or body wastes shall be demolished and any portion which may have come in contact with any human excreta or body wastes shall be disposed of in a manner that does not endanger the public health or otherwise constitute a nuisance.
D.C. Mun. Regs. tit. 21, r. 21-909