CRD Installation Standards & Environmental Compliance 2 — Questions and Answers
Question 1: Which federal regulation primarily governs the use of chemical grouting materials injected into boreholes for geothermal systems near groundwater?
- Clean Air Act
- Safe Drinking Water Act (Correct answer)
- Resource Conservation and Recovery Act
- Comprehensive Environmental Response Act
Correct answer: Safe Drinking Water Act
The Safe Drinking Water Act (SDWA) regulates Underground Injection Control, which governs substances injected into boreholes that could affect groundwater.
Question 2: What is the minimum recommended separation distance between a vertical geothermal borehole and a potable water well in most U.S. state codes?
- 10 feet
- 25 feet
- 50 feet (Correct answer)
- 100 feet
Correct answer: 50 feet
Most state codes require a minimum 50-foot separation between geothermal boreholes and potable water wells to prevent cross-contamination.
Question 3: When installing a horizontal ground loop in a wetland buffer zone, which agency permit is typically required in addition to local building permits?
- EPA Section 401 Water Quality Certification
- U.S. Army Corps of Engineers Section 404 Permit (Correct answer)
- OSHA 29 CFR 1926 Excavation Permit
- USDA NRCS Conservation Compliance Certificate
Correct answer: U.S. Army Corps of Engineers Section 404 Permit
Section 404 of the Clean Water Act, administered by the Army Corps of Engineers, regulates discharge of dredged or fill material into wetlands.
Question 4: Which IGSHPA standard specifies minimum grouting requirements for vertical closed-loop geothermal boreholes to protect groundwater?
- IGSHPA TR-006
- IGSHPA C560 (Correct answer)
- IGSHPA TC100
- IGSHPA WQ-200
Correct answer: IGSHPA C560
IGSHPA C560 provides the standard specifications for thermally enhanced grout used to seal geothermal boreholes and protect groundwater aquifers.
Question 5: A residential geothermal loop field is discovered to have a refrigerant leak from the heat pump into the ground loop. Which immediate action is required under EPA regulations?
- Notify the local utility company within 24 hours
- Repair the leak and document under EPA Section 608 requirements (Correct answer)
- File an emergency Superfund notification within 72 hours
- Shut down the system and wait for state environmental agency inspection
Correct answer: Repair the leak and document under EPA Section 608 requirements
EPA Section 608 of the Clean Air Act requires that refrigerant leaks be repaired promptly and that records be maintained for systems with charges above thresholds.
Question 6: What is the primary purpose of using thermally enhanced grout instead of standard bentonite grout in geothermal boreholes?
- To reduce installation costs by requiring fewer boreholes
- To improve thermal conductivity between the ground loop and surrounding formation (Correct answer)
- To comply with EPA drinking water contamination limits
- To prevent frost heave in shallow borehole sections
Correct answer: To improve thermal conductivity between the ground loop and surrounding formation
Thermally enhanced grout has higher thermal conductivity than standard bentonite, improving heat transfer efficiency between the HDPE loop and surrounding soil/rock.
Question 7: Under ASHRAE 90.1 energy code requirements, what must be verified during commissioning of a geothermal heat pump system?
- That the system uses only R-410A refrigerant
- That entering water temperature to the heat pump falls within manufacturer specifications (Correct answer)
- That the horizontal trenches are backfilled with native soil only
- That the loop field is located at least 200 feet from the property line
Correct answer: That entering water temperature to the heat pump falls within manufacturer specifications
ASHRAE 90.1 commissioning requirements include verifying that entering fluid temperatures are within design parameters to ensure efficient system operation.
CRD Installation Standards & Environmental Compliance 2
Which federal regulation primarily governs the use of chemical grouting materials injected into boreholes for geothermal systems near groundwater?