Patent ID: 9598233
Date: 2017-03-21
CPC Classifications: B65D

Claim:
1. A system comprising: a holding tank; a flexible floating cover; a mounting piece that secures to a sidewall of the holding tank; a mast element extending above an interior of a holding tank and having a first end attached to the mounting piece; a guide element with a first end attached to a second opposite end of the mast element, the guide element having a longitudinal axis extending into the interior of the holding tank, the longitudinal axis attached to or including a ballast element that hangs freely within the holding tank without contacting a base of the holding tank, wherein the guide element is configured to extend through and slideably engage an aperture in the flexible floating cover to allow the floating cover to rise and fall along the longitudinal axis of the guide element between the first end of the guide element and the ballast element responsive to changes to a volume stored within the holding tank.