For suitable construction, how far must one be away from a restrictive horizon?

The correct distance for suitable construction away from a restrictive horizon is 2 feet. This specification is grounded in the need to ensure that any sewage or effluent from an on-site sewage facility (OSSF) does not compromise the effectiveness of the system or lead to potential contamination issues. A restrictive horizon may include clay layers or bedrock that can impede drainage and affect the proper functioning of the sewage system.

By maintaining a 2-foot distance, it helps ensure that sufficient soil depth is available for proper filtration and absorption of waste. This distance supports the capacity of the soil to process effluent effectively while reducing the risk of pollutant migration towards groundwater or surface water bodies. In contrast, closer distances may hinder the system's operation, risking system failure or environmental health issues.