1997 Progress Report: The Effect of Plants on the Bioavailability and Toxicity of Contaminants in SoilEPA Grant Number: R825413
Title: The Effect of Plants on the Bioavailability and Toxicity of Contaminants in Soil
Investigators: Banks, M. Katherine , Schwab, Arthur Paul , Smith, J. Scott
Institution: Kansas State University , Purdue University
Current Institution: Kansas State University , Purdue University
EPA Project Officer: Lasat, Mitch
Project Period: January 1, 1997 through December 31, 2000
Project Period Covered by this Report: January 1, 1997 through December 31, 1998
Project Amount: $499,941
RFA: DOE/EPA/NSF/ONR Joint Program on Bioremediation (1996) RFA Text | Recipients Lists
Research Category: Hazardous Waste/Remediation , Land and Waste Management
Objective:The overall objective of this project is to evaluate the effect of plants on the bioavailability and toxicity of contaminants in soil. Sub-objectives are listed below.
Objective 1: Evaluate the effect of plant roots and their associated rhizosphere on the availability of soil contaminants for bioremediation by soil microbes and higher plants.
Objective 2: Investigate the fate of petroleum contaminants in plant/soil systems.
Objective 3: Quantify the contribution of weathering to reduced contaminant bioavailability and toxicity.
Objective 4: Determine the impact of plants on leaching of contaminants and the toxicity of leachates.
Objective 5: Develop a chemical extractant or sequential series of extractants to rapidly assess bioavailability.
Objective 6: Assess changes in rhizosphere microbial community associated with plants established in contaminated soil.
Objective 7: Evaluate the impact of root characteristics on contaminant bioavailability, toxicity, and bioremediation/phytoremediation efficiency.
Progress Summary:We have made significant progress on the experimental and field studies described below. Fate of 14C labeled contaminants in plant chambers. The chambers were constructed and the plants established in the soil in November 1997. The chambers were dismantled in June 1998 and soil, biomass, and leachate samples are currently being analyzed for target contaminants and 14C.
Effect of aging on contaminant bioavailability in soil-plant systems. The contaminated soil began the aging process in March 1998. The first assessment of contaminant concentration and toxicity will occur after six months of aging (October 1998).
Field evaluation of bioavailability and toxicity during phytoremediation. The Port Hueneme field study began in September 1997. The study area was constructed and plants established at the site. Soil, water, and biomass are sampled every three months. Irrigation and fertilization are performed as needed.
Development of an extraction method to predict bioavailability of soil contaminants. The extraction study is currently underway at Purdue University and should be completed by December 1998.
Future Activities:October, 1998 First sampling (6 months) for weathering study. Soil will be tested for contaminants and toxicity, and placed in greenhouse pots for plant phase of this study. Sampling at Port Hueneme is planned.
January, 1999 Sampling will be performed at Port Hueneme.
April, 1999 First take-down for 6 months weathering greenhouse study. Analyses of contaminants, and plant biomass and root characteristics will occur. Second sampling for weathering study (12 months). Analyses and greenhouse study for this soil begins. Sampling at Port Hueneme is planned.
July, 1999 Sampling will be performed at Port Hueneme.
October, 1999 Second take-down for 6 months weathering greenhouse study and first take-down for 12 months weathering greenhouse study. Analysis of soil and biomass will begin. Third sampling for weathering study (18 months). Soil analyses and greenhouse study for the 18 month weathered soil will begin. Sampling at Port Hueneme is planned.
January, 2000 Last sample collection at the Port Hueneme field site. Field study is complete.
April, 2000 Second take-down for 12 months weathering greenhouse study and first take-down for 18 months weathering greenhouse study. Analysis of soil and biomass will occur.
September, 2000 Second take-down for 18 months weathering greenhouse study. Analysis of soil and biomass will occur.
October, 2000 Research ends. Final report submitted.