SELECTED SPECIES AND AMENDMENTS FOR REVEGETATING SALINE FLUE-GAS DESULFURIZATION SLUDGE - GREENHOUSE STUDY

Codisposing low-volume wastes from electrical generating stations with flue gas desulfurization (FSD) scrubber sludge simplifies waste dispo sal but produces a saline waste that presents unique challenges to rev egetation. This greenhouse study identified plants amendments for reve getating a saline FGD sludge disposal pond in eastern Arizona. Surviva l and growth of 16 sown accessions plus two vegetatively propagated ac cessions of inland saltgrass [Distichlis spicata var. stricta (Torr.) Beetle] were investigated in saline FGD sludge (EC/e = 6.65 S m(-1)). Amendments used included two soils from the disposal site, Claysprings gravelly clay (Typic Torriorthent) and Sheppard sand (Typic Torripsam ment), composted steer manure, and N-P-K fertilizer. Soils and manure were added at 2:1 sludge/amendment (v/v). Plants were irrigated with a 1:1 mixture of disposal pond water and untreated well water (EC = 2.0 9 S m(-1)). One accession of inland saltgrass, two cultivars to tall w heatgrass [Elytrigia pontica (Pondq.) Holub 'Largo' and 'Jose'], Altai wildrye [Leymus angustus (Trin.) Pilger 'Praireland'], tall fescue (F estuca arundinacae Schreb. 'Alta'), and alkali sacaton [Sporobolus air oides (Torr.) Torr. 'Saltalk'] show promise for revegetating saline FG D sludge disposal sites. Survival rates were the same in unamended slu dge and in sludge amended with the clay soil or with N-P-K fertilizer. Plant dry matter produced was the same in unamended sludge and in slu dge amended with either of the soils or with N-P-K. Although survival rates were significantly lower with manure than with any other amendme nt, due to high EC values, growth was significantly greater by all mea surement, due to the high fertility of this treatment.