Why are leachate and methane monitored at a garbage dump?

• A. To prevent groundwater contamination by leachate and reduce the risk of explosion from methane.
• B. To promote methane production and increase leachate volume.
• C. To evaluate composting efficiency in the landfill.
• D. To monitor bird populations around the dump.

Answer: (A)

Landfills create two major hazards as waste breaks down: leachate, a contaminated liquid that can move through soil, and methane, a highly flammable gas produced by anaerobic decomposition. Monitoring leachate and methane directly targets these hazards to protect the environment and people.

Leachate monitoring tracks the quality and movement of the liquid that drains from the waste. If leachate is not collected and treated properly, it can contaminate groundwater or surface water. Regular checks help ensure the landfill’s liner and leachate collection system are working, detect any leaks early, and guide treatment and remediation efforts.

Methane monitoring focuses on the gas produced inside the waste mass. Methane can accumulate and create explosion or fire risks, and it can migrate into nearby buildings or spaces if not controlled. By measuring methane levels, the facility can vent or capture the gas safely and potentially use it as an energy source, while reducing odors and greenhouse gas emissions.

So the main idea is safety and environmental protection: preventing groundwater contamination from leachate and reducing explosion risk from methane. The other options don’t address these real hazards and purposes—promoting methane production, increasing leachate volume, evaluating composting, or monitoring bird populations aren’t the goals of landfill monitoring.