Daniel E. Meeroff

Application of photochemical technologies for treatment of landfill leachate

Because of widely varying practices in solid waste management, an all-inclusive solution to long-term management of landfill leachate is currently not available. There is a major technological need for sustainable, economical options for safe discharge of leachate to the environment. Two potential on-site pretreatment technologies, photochemical iron-mediated aeration (PIMA) and TiO(2) photocatalysis were compared for treatment of landfill leachate at laboratory scale. Results of bench scale testing of real landfill leachate with PIMA and TiO(2) photocatalysis showed up to 86% conversion of refractory COD to complete mineralization, up to 91% removal of lead, up to 71% removal of ammonia without pH adjustment, and up to 90% effective color removal with detention times between 4 and 6h, in field samples. The estimated contact times for 90% removal of COD, ammonia, lead, and color were found to be on the order of 10-200 h for PIMA and 3-37 h for TiO(2) photocatalysis. Testing with actual leachate samples showed 85% TiO(2) photocatalyst recovery efficiency with no loss in performance after multiple (n>4 uses). Pre-filtration was not found to be necessary for effective treatment using either process.

Evaluation of coastal ocean discharges and environmental impacts in southeast Florida.

This article outlines the current literature regarding anthropogenic inputs of nutrients and microorganisms into the coastal oceans. The concern about nutrients and microorganisms in coastal marine waters is that they may cause a shift in local populations of organisms and encourage invasive algae and coral diseases. The lack of baseline data on marine populations makes it difficult to determine the source of marine population shifts. This report focuses on the question of whether there is sufficient data to implicate coastal ocean outfall discharges of secondary treated wastewater effluent in southeast Florida as a causative agent in impacts to coastal communities. The literature does not appear to support evidence of population shifts from any particular source.

Environmental infrastructure and socio-economic indicators in San Pedro Sula, Honduras

Access to water and sanitation was evaluated with respect to socio-economic factors for San Pedro Sula, Honduras (SPS), a medium-sized industrial city. A multidisciplinary analysis was conducted using socio-economic distribution and infrastructure assessments to determine the nature and extent of any existing inequalities. Although piped water access was nearly universal, socio-economic status did not always correlate with quality of service. Other notable relationships were observed with monthly expenditures, homes with dirt floors, and topography. Results indicate that SPS would benefit from improved operation and maintenance of existing infrastructure, implementation of groundwater disinfection and source water protection, and construction of sewage treatment facilities.

Using Multiple Tracers to Evaluate Coastal Water Quality Impacts for Sewered and Non-Sewered Areas

When onsite treatment and disposal systems (OSTDS) are not properly sited or installed, they can be a potential risk to public health and a source of environmental degradation. There are estimated to be over 2.3 million onsite sewage treatment and disposal systems currently in use in Florida, serving approximately 4.5 million people. These systems discharge over 426 million gallons of treated effluent per day in to the subsurface soil environment. Nearly 40% of those systems are found along Floridas southeastern Atlantic coastline. Onsite system failure can result in problems that include direct exposure to inadequately treated sewage, ground and surface water pollution, and contamination of shellfish beds. Throughout the State of Florida, where the water table is high, septic tanks have proven to be problematic from a water resource perspective. Impacts are traced to a lack of regulation prior to the 1980s and to high densities of septic tanks on small lots. Moreover, many of these high-density developments were historically inhabited only in the winter months when the water table is low and performance optimal. When the water table is high, septic tanks cannot operate properly because the water table is above the drainage pipes, interfering with the normal hydraulic specifications and complicating pollutant migration modeling. Thus, the potential for groundwater and surface water contamination is increased, and clearly there is a need to quantify the contribution of environmental degradation attributable to OSTDS. The research team has investigated differences in sewered and non-sewered areas in Broward and Palm Beach Counties in Florida to attempt to quantify the nutrient loading contribution from septic tanks and also to determine the extent of observed nutrient contamination from other sources in a major urban setting. Recently, a unique opportunity to study a rural area in Taylor County, allowed the research team to investigate newer tracers. Taylor County (see Figure 1) is located in Northwest Florida along the Gulf of Mexico coastline directly south of Tallahassee. The total area of the County is 789,000 acres (3,191 km 2 ), of which approximately 15% is comprised of water bodies. Taylor County has four rivers, numerous canals, creeks, and springs, and nearly 60 miles of Gulf of Mexico coastline. The major tourist attractions are fishing and scalloping, particularly from July through September. Half of its southern coast is part of the Big Bend Sea Grasses Aquatic Preserve and is classified as Outstanding Florida Waters . Prior studies have been conducted by the Suwanee River Water Management District (SRWMD) and the Taylor County Health Department (TCHD) in Taylor County to determine if water quality criteria are being met. An ongoing beach monitoring program posts advisories approximately 46% of the time due to high concentration of indicator bacteria (>400 CFU/100mL for fecal coliform, >100 CFU/100mL for Enterococcus ). Maintenance of the microbiological quality and safety of water systems used for drinking, for recreation, and for the harvesting of seafood is imperative. Contamination of these water systems can result in high risks to human health and significant economic losses due to closures of beaches and shellfish harvesting areas.