Proper LP Inspection - Texas Onsite Wastewater Association
North Carolina Sea Grant (1982) • Background • Research based development • Intended for public and private guidance • Has become ‘Doctrine’ for LPD design • Specifically referenced in 30 TAC Chapter 285 • For a “less informed” professional community at time of publication • Technical knowledge of system design by professionals has greatly increased (soil science, hydraulics, electric pumps and controls, etc.)
North Carolina Sea Grant (1982) • Design Method • Determine length of trench to be installed • Trenches laid out with contour on topographic map of site • Most often all trenches of same length • Trenches connected by manifold or header pipe • Trenches split into groups from manifold to groups with elevation changes limited to roughly 2 feet differential. • Valve(s) set to pressurize group (typically one valve per group; may be multiple groups pressurized at same time) • Manifold pipe from pump tank to trenches may be connected to either highest or lowest trench (no preference stated).
Alarm Light Pump & Alarm on separat
hydromulch Berm & swale
Riser to grade with screws Masonry
References • EPA Onsite Wastewate