Options are not provided in the question. Th ecomplete question is as following:
A team of environmentalists are removing volatile organic pollutants from soil by circulating air through the soil using pipes. Which remediation method are they using?
A) air sparging B) natural attenuation C) soil vapor extraction D) bioventing
Answer:
A) air sparging
Step-by-step explanation:
Air sparging also known as in-situ volatilization is a soil remediation process in which volatile contaminants (VOCs) from the soil are removed using pressurised air into the groundwater.
Generally hydrocarbon-free gaseous medium is injected into the ground in the area of contamination, where hydrocarbons changes the state of contaminants to vapor state and then extracted through vacuum.
Hence, the correct option is A.