Abstract: Contaminating material is extracted from a body of water by providing a floating bed on which plants such as Cat Tails can be grown with their roots hanging into the body of water over an area where extraction of contaminating material from the body of water is required, growing the plants to take up the contaminating material from the body of water and harvesting the upstanding plant mass by moving the bed to a harvesting machine which cuts away the plant mass leaving at least part of the root mass to continue growing into a new season. The bed can be returned to a location for the next season.

Abstract: Contaminating material is extracted from a body of water by providing a floating bed on which plants such as Cat Tails can be grown with their roots hanging into the body of water over an area where extraction of contaminating material from the body of water is required, growing the plants to take up the contaminating material from the body of water and harvesting the upstanding plant mass by moving the bed to a harvesting machine which cuts away the plant mass leaving at least part of the root mass to continue growing into a new season. The bed can be returned to a location for the next season.

Abstract: Contaminating material is extracted from a body of water by providing a floating bed on which plants such as Cat Tails can be grown with their roots hanging into the body of water over an area where extraction of contaminating material from the body of water is required, growing the plants to take up the contaminating material from the body of water and harvesting the upstanding plant mass by moving the bed to a harvesting machine which cuts away the plant mass leaving at least part of the root mass to continue growing into a new season. The bed can be returned to a location for the next season.

Abstract: Contaminating material is extracted from a body of water by providing a floating bed on which plants such as Cat Tails can be grown with their roots hanging into the body of water over an area where extraction of contaminating material from the body of water is required, growing the plants to take up the contaminating material from the body of water and harvesting the upstanding plant mass by moving the bed to a harvesting machine which cuts away the plant mass leaving at least part of the root mass to continue growing into a new season. The bed can be returned to a location for the next season.

Abstract: A holding assembly for an edge of a flexible film sheeting where the assembly comprises an elongate flexible channel member for extending along the edge and an elongate locking strip detachably engagable within the channel member for clamping the associated film sheeting therebetween has the locking strip moved into place by a guide body arranged for sliding movement across a support surface such as the ground on which the film sheeting is located. The guide body having a slot therein for receiving the channel member and carries a pivotal lever including a pair of rollers for guiding and forcing the locking strip into place. The guide body is carried on a skid and moves underneath the edge of the film across the width of the opening to be closed.

Abstract: A holding assembly for an edge of a flexible film sheeting where the assembly comprises an elongate flexible channel member for extending along the edge and an elongate locking strip detachably engagable within the channel member for clamping the associated film sheeting therebetween has the locking strip moved into place by a guide body arranged for sliding movement across a support surface such as the ground on which the film sheeting is located. The guide body having a slot therein for receiving the channel member and carries a pivotal lever including a pair of rollers for guiding and forcing the locking strip into place. The guide body is carried on a skid and moves underneath the edge of the film across the width of the opening to be closed.

Abstract: Waste materials are composted in an elongate pit which is maintained covered to retain odors. The pit includes two rails each arranged along a respective side of the opening for receiving operating machines and a carriage for supplying a covering sheet. Each side edge of the sheet has attached thereto a channel shaped support member arranged for engaging over the respective rail so as to attach the side edge to the rail. A reel is mounted on the carriage and is arranged to roll the sheet and the two support members onto the reel and to un-roll the sheet and the two support members therefrom for deployment. An arch support bridges the support members and can flex to a flat condition from rolling on the reel. The carriage includes guides for moving the support members apart to a wider spacing for rolling on to the reel with the sheet flat and for guiding the support members onto the rails and for bowing the arch upwardly in the deployed position.