Vegetation of Waste Disposal Areas at a Coal‐Fired Power Plant in Kansas

Abstract

Abstract Disposal of scrubber sludge and fly ash waste from coal‐fired power plants is a costly problem for utilities. Current regulations call for the retired waste areas to be covered with topsoil, then seeded to produce a protective vegetative cap. We conducted field tests over a 3‐yr period to determine if a vegetative cover could be established without first adding topsoil to waste sites. Seven herbaceous and six tree species were planted on scrubber sludge and bottom ash sites. These substrates were first amended with fertilizer, and then hay, woodchips, or cow ( Bos taurus ) manure. The bottom ash was not capable of supporting vegetative growth, even with amendment. Tall wheatgrass [ Agropyron elongatum , (Host) Beauv.], tall fescue ( Festuca arundinacea Schreb.], yellow sweet clover ( Melilotus officinalis Lam.), and Japanese millet [ Echinochloa crusgalli (L.) Beanv.] grew well on scrubber sludge, as did eastern cottonwood (Populus deltoides Marsh.) and eastern red cedar trees ( Juniperus virginiana L.). Generally, herbaceous plants grew best on scrubber sludge to which manure and fertilizer were added, and the trees survived and grew best on scrubber sludge amended with woodchips and fertilizer. This study demonstrates that a good vegetative cover can be produced on scrubber sludge waste areas without first covering them with topsoil.