Would an inspector approve the following holding tank siting? 10 m from an uncased water supply well, 7 m from the house, 5 m from the property line, and 35 m from a natural spring source.

• A. Yes
• B. No
• C. Only if a variance is granted
• D. Not enough information

Answer: (B)

The main consideration is keeping a holding tank far enough from drinking-water sources to prevent contamination. An uncased water supply well has no protective borehole barrier, so contaminants from a holding tank can more easily reach the aquifer through soil and groundwater. A 10-meter separation from such a well is typically not adequate under common setback rules, which often require a much larger buffer (often 15 meters or more, depending on soil, well type, and local regulations). Because the well is so close, the risk to drinking water is too high, so this siting would be rejected by an inspector.

The other distances (7 m from the house and 5 m from the property line) are also factors the authority would check, but they do not override the primary safety issue here. The 35 m distance to a natural spring helps, but it doesn’t compensate for the problematic proximity to the uncased well. A variance might be considered in some cases, but as shown, the standard check would conclude this siting isn’t acceptable.