Characteristics and Utilizations of a Pilot Scale Aquifer Model

摘要

A pilot scale aquifer model, consisted of a tank with five types of unscreened sediments involving gravel, medium sand, fine sand, silt, and clay, was constructed in the laboratory. The average porosity of the aquifer was estimated at 0.1463 and 0.1459 by water supply and drainage tests, respectively. Among these material layers in the tank, medium sand layer was the main aquifer with a thickness of 40 cm approximately and specific yield ranged from 0.20 to 0.22. The leaching of clay soil layer on the top of fine sand had an obvious effect on the formation of hydrochemical characteristics of the aquifer. The detections of dissolved oxygen from monitoring wells indicated that there were biodegradation processes that degraded organic chemicals from clay soil in the aquifer. With the functions of supplying, draining, monitoring, abstracting, injecting and so on, the pilot scale aquifer model is being used to study on renovating groundwater system contaminated by leaks of gasoline. So far, the distributions of BTEX contaminants have been detected in the aquifer by destroyed experiments that 4 L gasoline was injected, to the aquifer. The detected results will play a basic role in studying on intrinsic biodegradation and enhanced engineered biodegradation technologies continuously.