b'Septic system leach fi elds eff ectively eliminate almost all bacteria and many viruses. The effluent leaving the tank contains tens of thousands of fecal bacteria, but after percolating through four feet of soil, the bacterial count is reduced to one per gram of soil.Nutrients like nitrogen are not completely removed during their transit through a typical septic system. So they proceed into the groundwater and eventually into the coastal waters. The septic system serving a family of three releases enough nitrogen to contaminate hundreds of gallons of marine water on a daily basis. Excess nitrogen entering a salt pond or bay in the form of nitrate leads to:Phytoplankton blooms, causing cloudy or greenish coloring Excess growth of macro algae, sea lettuce Decline or outright loss of eelgrass beds. Increase in decayed plant material at bottom Decrease of shellfi sh like scallops and soft-shell clams.Odors from decay of excess vegetation.As the density of housing development increases, so does the risk of nitrates contaminating nearby wells.Excess phosphorous (phosphates) from household wastewater joins the groundwater and fl ows to our freshwater lakes and ponds where it stimulates: Plant growth Depletion of oxygen Decay at the bottomAs the density of housing development increases, so does the risk of nitrates and phosphates contaminating nearby Town and private wells. Take Care of your Septic System:Have it pumped out regularly: The system should be pumped regularly to remove the sludge and the fl oating scum. The frequency depends on how you use your system and what goes down the drain. All systems should be pumped every three to fi ve years to avoid septic system failure.Conserve water: Reducing the fl ow through your system will reduce theMaintenance is the movement of solids and scum into the soil absorption system.single most importantDont overload the system: A dripping faucet or a leaky toilet can addconsideration in making hundreds of gallons of water to the system each week. If you are goingsure a septic system will work well over time. to have a large gathering, rent a portable toilet to reduce the demand onWhat goes down the your septic system. Stagger your washing machine and dishwasher use todrain or toilet either spread out the fl ow. nds its way into the soil or stays in the septicDont install or use a garbage disposal: These devices add large amountstank until it is pumped of grease and organic matter to the system and will shorten the life ofout. your soil absorption fi eld. Page 27bluepages.indd 27 8/26/2009 1:50:32 PM'