ABSTRACT
Environmental scientists and engineers have focused their attention on a new area of soil and groundwater pollution: soil gases. Because of soil variation, an on-site test for gas yield, zone of influence, vertical efficiency, and vapor content should be conducted before final design and approval of a remediation procedure. The time required for remediation of heterogeneous soils depends upon the proportion of contaminated material exposed to bulk air flow. A simple double-well test was conducted to measure horizontal changes in conductivity using direct velocity measurements. The installed flow meters intercepted gas flows at their highest velocities. Soil vapor extraction/sparge systems should be monitored at least once a month. The monitoring allows for fine tuning of the system. Sparging refers to air injection into the saturated zone of the aquifer in order to remove volatile organic substances. The sparge-point wellfield can be superimposed within the conceptual relationship of the double-well withdrawal/injection combination.
