2018-07-26 Meeting Minutes (EMC)

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• A septic system has a tank, and its purpose is to remove the solids so they don’t go into the leachfield and plug it up. Some other processing goes on, and then the somewhat clarified water goes into a leachfield which has pipes with holes in them, and it drains through the water stratum and ultimately to the groundwater. • Science says cesspits and septic systems are pretty much the same. It is his opinion, and that of many others, that the rush to put in septic systems is a very expensive mistake. • Long Island, New York, is a community on septic systems, and it has numerous water quality problems associated with various kinds of algae, some of which are dangerous. The algae has been an olfactory, visual, and biological catastrophe, and it is mainly attributable to the 100,000 septic systems on the island. • Kihei Beach on Maui has been getting algae blooms, and it has been attributed to wastewater injection wells in Kihei. • The human nitrogen cycle: The extra nitrogen in our diet goes into the waste system via urination, and it flows wherever water flows. It is not absorbed by soil or rock. If you do the math, our homes in Hawaiʻi are depositing between 700,000 and 1.3 million pounds of nitrogen into the environment every year from our cesspools. If you add in the septic systems, there will be even more nitrogen. • The Stony Brook University has a Center for Clean Water Technology, which has been commissioned to take on the problem of nitrogen removal. They have been working for years on it and have come up with a biofilter which has been able to reduce nitrogen by 60% to 70%. Dr. Bennett detailed how the biofilter works in removing nitrogen. Another system with a liner has been getting a 90% reduction in nitrate. • This new technology is exciting. It is low tech, there are no pumps, no electricity, and nothing to monitor. • On another front, a company is using technology called a membrane bioreactor, and is working on getting Hawaiʻi DOH approval. The technology works well, but the difficulty is that people need to have access to their cesspit to install it. It also requires technician maintenance. • The membrane bioreactor is the size of a large suitcase and has the ability to filter the constituents of wastewater to allow clean water to come through. It contains nitrate, so has to go through an anaerobic denitrification process, and then it can be discharged or reused. These membrane bioreactors are in use now.