SCMWC operates four deep wells in Senior Canyon that produce groundwater for agricultural needs. This well water contains differing concentrations of hydrogen sulfide (H2S) gas. Hydrogen sulfide is a secondary contaminant, which means that it is not toxic, but aesthetically has the odor of rotten eggs and thus is unsuitable for drinking or bathing. H2S is very common in groundwater throughout the country.
To remove 90-95% of the H2S in its well water, SCMWC purchased a Packed Tower Aerator (PTA) at a cost of $60,000. The tower is a 40-inch diameter cylinder and is 34 feet tall. It is packed with plastic balls that look similar to whiffle balls. Water is pumped into the top of the aerator while a powerful blower pumps air into the bottom of the unit. The air travels upwards in a mass of bubbles and comes out from a hole in the top of the aerator. The H2S attaches to the air molecules, thereby lowering the concentration of H2S in the water.
Once the concentration of H2S is lowered in the water from the four deep wells, the water can be blended with water coming from the West Fork, North Fork, and Tunnel in the company’s potable line and then treated with sodium hypochlorite. This treatment process further lowers the H2S concentration through chemical oxidation and enhances Senior Canyon’s supply of potable water.