A Short Groundwater Quiz (3/18/98)

1. What approximate percentage of Mainers rely on ground water for their drinking water? 30%, 60%, 70%, or more than 90%?	ANSWER
2. A well drilled into which of the following materials is most likely to produce large amounts of ground water (greater than 500 gpm)? Till Clay Sand Bedrock (ledge)	ANSWER
3. In an area where residential development has occurred, you notice that average groundwater levels have declined over a two year period. What are two factors that could account for the water table drop?	ANSWER
4. What is the "base flow" of a stream? (Hint: if the ground water table drops, how may that affect a stream?)	ANSWER
5. Which of the following threats to groundwater has resulted in contamination of the most wells in Maine? Bacteria and nitrates Salt from sea water intrusion Salt from roads and sand/salt piles Oil and gas from underground storage or spills	ANSWER
6. In Maine, which of the following contaminants occur most often naturally in groundwater? Check all that apply. Manganese Formaldehyde Lead Radon Copper Polycholorinated Biphenyls	ANSWER
7. A previously forested area is developed as a shopping mall and light industrial area (with machine shops, service stations, and furniture refinishers). Stormwater from paved areas is discharged to groundwater in infiltration basins. Name five stormwater contaminants that could affect groundwater.	ANSWER
8. What threats to groundwater are posed by excessive spreading of biosolids (ex. sludge or manure) on agricultural land?	ANSWER
9. What is the difference between a primary and secondary drinking water standard?	ANSWER
10. You hear someone say: "I'm thinking of cutting the trees in that wet area, so the area will dry up." Actually, when trees in a forested wetland are cut, the area often gets more wet. Why?	ANSWER