|Dungan, Robert - Rob|
Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 11/3/2004
Publication Date: 11/3/2004
Citation: Dungan, R.S., Kukier, U. 2003. Blending foundry sands with soil: effect on dehydrogenase activity [abstract]. Agronomy Abstracts.
Technical Abstract: Each year the foundry industry generates several million tons of waste foundry sands (WFSs) that are suitable for the production of manufactured soils; however, their impact upon soil microbial activity is largely untested. In this study we monitored the dehydrogenase activity (DHA) over a 12-week period in soils blended with molding sands [green sands (bentonite coated silica sand) from iron, aluminum and brass foundries] and with resin binders (Novolac, furan, and phenolic urethane) at a rate of 10, 30, and 50% (dry wt. basis). In soils amended with green sands, the DHA decreased as the blending ratio was increased. The most significant impact on DHA occurred in soil blended with brass green sand, which had very high levels of Cu, Pb, and Zn. Over the 12-week period, the microbial activity in the soil blends did not exhibit recovery when compared to the soil control. In soil amended with resin binders, the DHA generally decreased as the blending ratio was increased; however, at week 4 the DHA was higher in soils amended with furan and phenolic urethane binders than in the soil control. It is suspected that the microorganisms in these treatments are using the resin binders as a carbon source. Overall, the DHA assay may be a useful technique to identify WFSs that could cause negative impacts when beneficially used in the environment.