Which of the following statements about landfill gas (LFG) contamination is/are correct?
1. LFG can directly transfer NMOCs to groundwater.
2. Condensation of LFG in the vadose zone can lead to contamination.
3. LFG cannot be used as an energy source.
1
Only 1 and 2
2
Only 2 and 3
3
Only 1 and 3
4
All are correct.