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Cudjoe Regional Wastewater Treatment System. Let’s Finish the Job Well. Wastewater injected in shallow wells moves to surface waters. Florida Keys National Marine Sanctuary Water Quality Protection Program 2013 Report to Congress (pg. 22).
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Cudjoe Regional Wastewater Treatment System Let’s Finish the Job Well
Wastewater injected in shallow wells moves to surface waters Florida Keys National Marine Sanctuary Water Quality Protection Program 2013 Report to Congress (pg. 22) “Wastewater disposed into a shallow injection well can rise toward the surface and contaminate residential canals and other near- shore waters as shown in this experiment using viral particles as tracers (Paul 1997).”
Wastewater injected in shallow wells moves to surface waters “Groundwater movement in the Florida Keys is quite different than most coastal systems. Groundwater and surface waters continuously interact due to the porous nature of the water table aquifer. “ “When tides are high in the Atlantic, Atlantic surface water is pushed into the subsurface and groundwater flows toward Florida Bay. When tides are low, groundwater flows toward the ocean. This continual sloshing of groundwater controls the overall path of the injected wastewater and septic effluent in the subsurface, thus increasing the possibility of surface water contamination.” “Submarine Groundwater Discharge, An Unseen Yet Potentially Important Coastal Phenomenon”, Corbett, Burnett, Chanton (National Sea Grant College Program of NOAA) at page 5.
Wastewater injected in shallow wells moves to surface waters “After injection into a well, the less dense buoyant wastewater plume rises toward the surface.” CRWWTP is sited at a closed landfill “Results demonstrated that wastewater is rapidly transported upward toward the surface and laterally, which delivers tracers placed into injection wells to nearby surface waters after several days to weeks…” Kevin Dillon, Gulf Coast Research Laboratory, Ocean Springs, Mississippi Tropical Connections, page 143 (2012)
Lower Keys Waters Require Very Low Nutrient Levels “The Florida Keys coral and seagrass communities are dependent on very low nutrient conditions. Any increases in nutrient loading results in the beginning of changes in the biotic community and can ultimately result in green water (high chlorophyll) and/or smothering of hard bottom communities by benthic algae.” William L. Kruczynski, Ph.D. Retired EPA Scientist
Florida Law acknowledges the unique geology and fragile waters of the FKNMS
Minimum Disposal Requirement: Provide reasonable assurance of no harm to surface waters
Deep Well and 1 MGD: It is all about the Money Monroe County Sanitary Master Plan (2000) . “Deep well injection is mandated in Monroe County for effluent discharged from plants of 1 mgd capacity and greater. Because deep well injection eliminates all wastewater nutrients from the environment, deep well injection was also evaluated for the 0.5 mgd plant size but was found to be more expensive than shallow well injection.” Pg 3-22. (width of wells not to scale)
AWT leaves nutrients in the water far in excess of DEP Water Quality Standards for Lower Keys. “The total nitrogen (TN) and total phosphorus levels in the back country waters nearby are already too high… The addition of any further TN and TP loads will contribute to violation of numerical nutrient standards recently adopted by DEP.” Brian Lapointe, Ph.D. June 12, 2014 Phosphorous Nitrogen
Although AWT will result in a net reduction of nutrients from the FKNMS as a whole …
RAMP-UP FLOW PROJECTIONS (MGD) 2.35 Even relatively small levels of discharge during the expected ramp up period … can impact the surface waters of the Cudjoe Basin. Brian Lapoint, Ph.D. 1.99 1.44 1.18 1.07 1.00 .89 .94 .72 .80 .58
RAMP-UP FLOW PROJECTIONS (MGD) Even relatively small levels of discharge during the expected ramp up period … can impact the surface waters of the Cudjoe Basin. Brian Lapointe, Ph. D.
Cudjoe Regional Wastewater Treatment System Let’s Finish the Job Well