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Process Specialties "EXCELLENCE IN PROCESS ENGINEERING AND SUPPORT' June 3, 2011 Timothy R. O'Brien Engineering Geologist Central Valley Regional Water Quality Control Board 11020 Sun Center Drive, #200 Rancho Cordova, CA 95670-6114 Subject: PSI Wastewater Characterization Report Dear Mr. O'Brien, Per your request dated April 20, 2011 we have completed modifications to our wastewater treatment system and we have also finished the required wastewater and well water testing using an EPA Certified laboratory. After your visit we began working on our two wastewater treatment systems to better control the pH of our wastewater discharges. These discharges consist mainly of Ultra Pure Deionized water (that we manufacture/purify on site from well water) and small amounts of neutralized Sulfuric Acid (as Sodium Sulfate after neutralization) and neutralized Hydrofluoric Acid (as Sodium Fluoride after neutralization). Information is attached to this report for both of these harmless compounds. As you know we are engineers and we found in both our research and our development work, that the neutralization of Ultra Pure DI -Water and subsequent tight pH control, is much more difficult than the neutralization of normal water, and more challenging than we thought it would be. However, with diligent work, combined with the purchase of newer caustic injection systems and new more sophisticated pulse pH controllers (one for each system), we are now able to maintain a stable pH control on both systems. We also changed from using 50% Sodium Hydroxide (Caustic Soda) to a more dilute 30% solution for neutralization. Attached to this report you will find the logs for systems 1 & 2 for the month of May. All the discharges over the past month of testing and production are now within the required specification of 6.0 - 9.0 pH. Most are within our new target range of 6.5 - 8.5 pH. During the past month a lot of testing and tweaking was going on, so you might note on the logs an above normal count of discharges on certain days. This was due to testing, and most of those discharges were half the volume of normal (also normal is now 150 gallons per discharge, for better pH control). While working with the Laboratory, Torrent Labs in Milpitas, we learned a lot about both our discharges and about the incoming well water we purify and turn into DI -Water. As we first suspected and subsequently discovered, the ground water in our area is non -potable and if drank it can pose significant health risks.