DECONTAMINATION PROCESS

Solutions containing pesticide wastes from greenhouses, for example, are decontaminated in a system including a soil bed reactor. Waste water from the greenhouse goes to a sample tank from which samples are withdrawn for assay of toxicity. Water from the sample tank goes to a holding tank, or to a downstream subsystem if toxicity level is low. Water in the holding tank is aerated to promote degradation of toxic materials. Water from the holding tank is applied near the upper surface of a layer of soil in the soil bed reactor. Air from the sample tank and holding tank, and intermittently, air containing pesticides from the greenhouse, is also passed through the layer of soil in the soil bed reactor. Microbial action in the soil degrades toxic materials in both the gaseous and liquid streams. Water from the soil bed reactor may then be discharged to a pond populated by plant and animal species which promote further degradation of any remaining toxic materials before the water is discharged from the system. A bioassay technique employing aquatic amphipods sensitive to water borne toxic materials is provided for routine screening of toxicity levels in the various solutions in the system.