PDFWAC 246-272A-0300
Abandonment.
Persons permanently abandoning a sewage tank, seepage pit, cesspool, or other sewage container shall:
(1) Have the septage removed by an approved pumper; and
(2) Perform one of the following:
(a) Remove and dispose of sewage tanks and other components in a manner approved by the local health officer; or
(b) Leave the sewage tanks and components in place. Remove or destroy the lid if possible and fill the void with soil or gravel; and
(3) Grade the site to the surroundings.