In which conditions should no leaching system be constructed?

High groundwater conditions are critical when assessing the suitability of a site for a leaching system. When the water table is high, the risk of contamination and system failure increases significantly. The leaching system relies on the natural percolation of effluent into the soil for treatment and dispersal. If the groundwater is already elevated, it can interfere with this process, preventing the effluent from filtering through the soil adequately. As a result, untreated or partially treated effluent may flow directly into the groundwater, posing environmental and public health risks.

The other conditions listed, while potentially challenging, do not inherently prohibit the construction of a leaching system like high groundwater does. Dry soil conditions may require different design considerations but can still support a leaching system with proper adjustments. Rocky terrain can complicate installation and affect drainage, but it does not automatically disqualify the site. Low rainfall areas may influence the moisture levels and performance of the system, but they still may allow for successful leaching system construction with proper engineering solutions.