In tidally effected areas the production of sulfuric acid from surrounding landforms can be neutralized using natural carbonate in salt water.

   Dry cracked drain beds.                                                           

     Significant oxidation of sulfidic sediment at a depth of 300mm.                                                 

This photo shows the black iron monosulfide, grey benign unoxidised passive acid sulfate soils (PASS) marine mud and the oxidized region from drying and cracking all in close proximity.

The Calibrated Flood Gate Valve allows for managed amounts of seawater relying only on tidal flow.

This involved allowing managed amounts of seawater into the drainage system to essentially keep the drains in a wet un-oxidized state and also neutralize acidity from surrounding fields.