TL-3 Sizing for any product should not be considered “Generally Approved” The loading rates are way too high for the worst of conditions! Why would you take the worst conditions and make the systems smaller and lower? Systems in TL-3 conditions should be raised up and larger.

 Sites that have less than 6” of suitable in situ soil should be raised up to 12” above restriction and use an approved UV device and loaded at TL-2. Sites that have 6” of suitable in situ soil should be raised up 6” and loaded at TL-2.

If a site requires a deviation from this an engineer may make a plan that fits the constraints of the site as a custom engineered plan, which would not be considered “Generally Approved”.