Common guidelines require at least 50' clearance distance between a well and a septic system tank or 150' between a well and a septic drainfieldseptic drainfieldThe drain field typically consists of an arrangement of trenches containing perforated pipes and porous material (often gravel) covered by a layer of soil to prevent animals (and surface runoff) from reaching the wastewater distributed within those trenches.https://en.wikipedia.org › wiki › Septic_drain_fieldSeptic drain field - Wikipedia or leaching bed but you will see that different authorities may recommend different distances. Local soil and rock conditions can make these "rules of thumb" unreliable.