At a minimum, VDH should publish the scientific documentation that warrants an across the board 25% reduction in sizing using gravelless. I understand the concept however I would like to see the track record of theses reductions actually working over a minimum of 10 years. As a private sector AOSE I rarely spec gravelless systems and I NEVER take a reduction. I've had two experiences with gravelless systems. Both times the installer used gravelless technology without designer permission.

1. EHS designed conventional; installer used chambers and took the reduction. EHS approved at inspection. Within a little over a year the system was blowing out the end of the trenches. The homeowners, due to lack of additional money and that they had signed a waiver and felt they were stuck with it, dealt with the failing system for a few years. They finally called us and we added the "left out" trenches plus one additional (used gravel in all) and they owners are having NO problems with the system (almost 2 years later). These were class II conventional soils.

2. AOSE designed conventional using land management; installer used chambers but did not take a reduction; system started failing within a couple months...blowing out of the dbox. These were very heavy Class III soils 80 - 90 mpi. They only way to get this system working again was to put it on time dosing. There are 100's of conventional systems using land management in that area and all are gravel and all are working just fine with standard dosing. Only this one, the only one using chambers, had problems.

Another thing that bothers me about this legislation is the lack of restrictions due to site and soil conditions. For example, what about a repair in nonconventional soils. Would it be appropriate to take a 25% reduction on a site with a very shallow water table (say anything less than 18") with a typical 18" install? What about this gravelless reduction combined with other reductions (for ex. water saving devices or TL-3 treatment).

I think more investigation into this arbitrary reduction needs to be done. More guidelines as to when it's appropriate to take these reductions. Remember, the only person that truly loses when these systems prematurely fail is the Home Owner.