D.C. Code § 8-637.03: Environmental Savings Account Program.

The Mayor shall establish an Environmental Savings Account Program which shall permit any person, to establish an Environmental Savings Account (“ESA”) for the purpose of accumulating funds to be used for the cleanup or the redevelopment of a contaminated property. Funds deposited in an ESA and the interest earned on the funds shall be exempt from District income tax; provided, that any funds withdrawn that are not used for cleanup and redevelopment shall be subject to income tax and a 10% penalty.