Abstract: A method of ballasting a cover of a sludge digester that is comprised of a storage tank and the cover. The method includes placing a ballast into the storage tank in a first predetermined position, placing the cover onto the storage tank, lowering a lifting member of a lifting device through an access port in the cover and into the storage tank, securing the lifting member to the ballast, using the lifting device to lift the lifting member and the ballast until the ballast is in a second predetermined position that is substantially above the first predetermined position, engaging a support bracket attached to the cover with a support member; and securing the ballast to the cover with the support member while the ballast is in a third predetermined position that is substantially below the second predetermined position.