Guidelines for Healthy Food Production in an Urban Brownfield: Is Aquatic Vegetation Safe for Composting?

Abstract

Sibley Mill, located in the community of Harrisburgnear Augusta University, is a designated brownfield. The property was the site of theConfederate Powder Works and later that ofa cotton mill.Soil contaminantsinclude arsenic, barium, cadmium, chromium,lead and mercury.There are documented cases of children in this community with elevated blood concentrations of lead. Risks associated with lead poisoning are damage to the brain and nervous system, slowed growth and development, and behavioral problems.The benefits of urban agricultureare wellestablished, but currently there are no guidelines for safe methods of food production in brownfields. Aquatic vegetation is removed weekly from the Augusta Canal to enablehydroelectric powergenerationat Sibley Mill. We are using this vegetationto implementa novel approach for the production of compostfor raised-bed gardening.We measured the concentrations of 14 heavy metals, prior to composting, to establishbaseline data. Concentrations of barium(253.3-962.4 ppm)and lead(4.1-16.5ppm)exceed the guidelines recommended for drinking waterand are the two metals of greatest concern for the productionof safe, usablecompost.