Phytoremediation: Risk or benefit?
The proposed use of phytoremediation at an increasing variety of contaminated sites has resulted in concerns by regulating agencies that a successful removal of constituents from contaminated sludge or soil by plants might result in the unwanted transfer of these constituents to the food chain. As part of the basis for a corrective measures study for a potential remedy, this pathway may need to be evaluated. Different constituents of concern result in different transport issues. For volatile compounds, the evolution of gases from plants as part of evapotranspiration may be an issue. This paper discusses the risks associated with polycyclic aromatic hydrocarbons (PAHs) that are frequently present at hazardous waste surface impoundments for which phytoremediation may have attractive cost advantages over conventional closure methods. Central to an analysis of potential uptake effects is an evaluation of constituent transport, exposure pathway and toxicity. Methods by which each of these can be estimated are presented. Regulatory frameworks under which these evaluations may be performed at the state level are still evolving, in fact Texas issued new proposed regulatory language pertaining to ecological risk as this paper was going to print. The attractiveness of phytoremediation in a RCRA setting is greater if a phytoremediation-based cover can be substituted for a traditional RCRA landfill cap. At the federal level some flexibility has now been provided, but it must be adopted by RCRA- delegated states to be useful. Alternatively, a demonstration that the phytoremediation-based cover somehow meets the RCRA closure design criteria for caps must be made. Work to make this kind of demonstration compelling is underway under the oversight of EPA.
- Research Organization:
- Environmental Resources Management, Beaumont, TX (US)
- OSTI ID:
- 20006485
- Report Number(s):
- CONF-990608-; TRN: IM200008%%92
- Resource Relation:
- Conference: Air and Waste 92nd Annual Meeting and Exhibition, St. Louis, MO (US), 06/20/1999--06/24/1999; Other Information: 1 CD-ROM. Operating Systems: Windows 3.1, '95, '98 and NT; Macintosh; and UNIX; PBD: 1999; Related Information: In: Air and Waste 92nd annual meeting and exhibition proceedings, [9500] pages.
- Country of Publication:
- United States
- Language:
- English
Similar Records
Clean closure of former hazardous waste impoundments using statistical analysis of constituent concentrations in associated media
A thick homogeneous vegetated cover design proves cost - and schedule-effective for the reclamation of uranium mills sites near Spokane, Washington