CWD Water Quality & Environmental Regulations 2 — Questions and Answers
Question 1: Under the Safe Drinking Water Act (SDWA), which agency sets National Primary Drinking Water Regulations?
- OSHA
- EPA (Correct answer)
- USGS
- CDC
Correct answer: EPA
The EPA establishes National Primary Drinking Water Regulations (NPDWRs) under the SDWA to protect public health.
Question 2: What does a Maximum Contaminant Level Goal (MCLG) represent?
- The legally enforceable limit for a contaminant
- The level at which no known adverse health effects occur (Correct answer)
- The detection threshold of a contaminant
- The treatment technique required for removal
Correct answer: The level at which no known adverse health effects occur
MCLGs are non-enforceable public health goals set at the level at which no known or anticipated adverse effects on health occur.
Question 3: Which test is typically performed first when assessing a new well for potable use?
- Volatile organic compound (VOC) scan
- Coliform bacteria test (Correct answer)
- Heavy metals panel
- Radon analysis
Correct answer: Coliform bacteria test
Coliform bacteria testing is the standard initial indicator test for microbiological safety of a new potable well.
Question 4: A well is located 40 feet from a septic drain field. What is the primary regulatory concern?
- Excessive iron leaching
- Nitrate and pathogen contamination from sewage effluent (Correct answer)
- Lowered static water level
- Increased hardness levels
Correct answer: Nitrate and pathogen contamination from sewage effluent
Setback distances from septic systems are required because sewage effluent can introduce nitrates, bacteria, and viruses into groundwater.
Question 5: Which naturally occurring contaminant is most commonly associated with granite bedrock aquifers and is a known carcinogen?
- Iron
- Manganese
- Arsenic (Correct answer)
- Calcium
Correct answer: Arsenic
Arsenic naturally occurs in granite and other rock formations and is a Group 1 human carcinogen regulated under the SDWA.
Question 6: What is the primary purpose of a sanitary well seal?
- To increase well yield
- To prevent surface water and contaminants from entering the well annulus (Correct answer)
- To reduce pump vibration
- To maintain artesian pressure
Correct answer: To prevent surface water and contaminants from entering the well annulus
A sanitary well seal closes the annular space between the casing and borehole to prevent surface contamination from entering the well.
Question 7: Under most state regulations, which chemical is used for shock chlorination of a newly drilled well?
- Sodium fluoride
- Potassium permanganate
- Sodium hypochlorite (bleach) (Correct answer)
- Sulfuric acid
Correct answer: Sodium hypochlorite (bleach)
Sodium hypochlorite (household bleach) or calcium hypochlorite is used to disinfect new wells through shock chlorination.
CWD Water Quality & Environmental Regulations 2
Under the Safe Drinking Water Act (SDWA), which agency sets National Primary Drinking Water Regulations?