Karen M. Mancl

Development of a Metric To Test Group Differences in Ecological Knowledge as One Component of Environmental Literacy.

Abstract Environmental literacy has been defined in numerous ways and attempts have been made to measure how environmentally literate people are. Many attempts to measure literacy have instead measured peoples knowledge about pollution and their attitudes toward the environment. According to many environmental education experts, knowledge and attitudes are important components of environmental literacy, especially if the goal of environmental education is to change behavior. However, the experts also indicate that, to change an individuals behavior, knowledge about the environment must be associated with environmental sensitivity, personal beliefs, and decisionmaking and problem-solving skills. The research presented in this article contributes to environmental literacy research by offering a tested, valid survey instrument to measure ecological knowledge—one component of environmental literacy. In this article, we provide an example of how this instrument can be applied by comparing knowledge levels among diverse groups of Ohio citizens.

Biomass accumulation and carbon utilization in layered sand filter biofilm systems receiving milk fat and detergent mixtures.

This research evaluated utilization of organic compounds and biomass accumulation in three different layered sand filter biofilm systems renovating a mixture of detergent and milk fat. Organic compounds were measured as chemical oxygen demand (COD) and biomass as ATP. A two-layer sand filter with coarse sand on the top and fine sand at the bottom; a three-layer sand filter with pea gravel on the top, coarse sand in the middle, and fine sand at the bottom; and a two-filters in-series sand filter biofilm system each received mixtures of butterfat and detergent. While the three-layer sand filter system had greater COD utilization capacity due to a longer filter run, the two-filters in-series sand filter system had greater COD utilization efficiency. The COD utilization was highly associated with the period of filter run to clogging. The decrease of COD utilization rate could lead to the clogging of sand filters. To maintain long filter runs without clogging, a COD loading rate of 2100 mg O(2)/m(2)/h was recommended for three-layer sand filters and 1800 mg O(2)/m(2)/h for two-layer sand filters for high fat content wastewater. In the two-layer sand filters and the three-layer sand filters, biomass did not seem to accumulate in any particular layer on a unit volume of sand. However, based on unit surface area, the coarse sand layer accumulated more biomass than the fine sand layer and the pea gravel layer.

Effect of inoculation on the biodegradation of butterfat-detergent mixtures in fixed-film sand columns

Abstract The purpose of this work was to investigate the feasibility of biodegradation of butterfat using an aerobic sand column system. Two bench-scale sand columns were inoculated with lipolytic microorganisms to colonize the sand with an active biofilm, and two uninoculated columns were used as controls. Butterfat was fed daily to the columns in artificial wastewaters that were supplemented with a detergent to provide emulsification. Sand columns exhibited physical infiltration, trapping butterfat in the sand, and resulted in an apparent high degree of COD and BOD5 removal from the effluent. Accumulation of biomass on the sand grains was demonstrated by measurement of ATP. Biomass accumulated in the columns over the 259-day experiment. At the end of the experiment, the amount of biomass was comparable in inoculated and uninoculated columns. Uninoculated columns were shown to lag behind inoculated columns by about 100 days in COD removal.

Pretreatment of turkey fat-containing wastewater in coarse sand and gravel/coarse sand bioreactors.

Fat, oil and grease in wastewater can be difficult to treat because of their slow decomposition. Traditional pretreatment facilities to remove fat, oil and grease from wastewater are increasingly costly. The hypothesis in this study was that pretreatment of animal fat-containing wastewater in sand and sand/gravel filters facilitates the conversion of slowly degradable organic matter measured as the difference between chemical oxygen demand (COD) and 5-day biochemical oxygen demand (BOD(5)) for subsequent biological treatment. The pretreatment was evaluated using simulated turkey-processing wastewater and coarse sand and sand/gravel filters at a constant hydraulic loading rate of 132L/m(2)/day. Two types of fixed media reactors were employed: (i) one set with a varying depth of coarse sand, and (ii) the second was similar but with an additional pea gravel cap. The results indicated that the relative removal of COD was slightly improved in the sand bioreactors with a pea gravel cap irrespective of the depth of coarse sand, but partial conversion to BOD(5) was not consistently demonstrated. Pea gravel may act as a sieve to entrap organic matter including fat globules from the wastewater. Multiple dosing at the same daily loading rate slightly improved the treatment efficiency of the sand bioreactors. The ratios of influent-COD/effluent-COD were always greater than 1.0 following a change in the dosing frequency after a rest period, suggesting that organic matter, specifically fat globules in this case, was retained by the column matrix.

Treatment of Sanitary Sewer Overflow with Fixed Media Bioreactors

Fixed media bioreactors (biofilters) are a promising and proven technology used for wastewater treatment in unsewered rural areas. As an on-site treatment system, it can potentially provide high treatment efficiency with a relatively low cost and maintenance. This research expanded the application of fixed media bioreactors and tested their feasibility in the treatment of sanitary sewer overflows (SSO) at high hydraulic loading of 0.2 m/h. Sand, peat, and textile (felt) were used as media to treat simulated 6-h peak flows for a 25-year SSO event in the city of Columbus, Ohio. The influent SSO was a mixture of primary sludge from a wastewater treatment plant diluted with tap water. The efficiency of treatment was measured as changes in the concentrations of biochemical oxygen demand (BOD5), chemical oxygen demand (COD), and total suspended solids (TSS). Sand as a filter medium had the best removal of organic matter with average 84% reduction of BOD5 and 90% of COD. The TSS removal was more than 90% in all media. Peat and felt were somewhat more efficient than the sand in the TSS removal. The media type and influent BOD5 concentration were two major factors that impacted the treatment of BOD5 (p<0.007). For the treatment of COD, significant factors were media type, influent concentration, and time course of loading in each SSO event (p= 0.001).

Evaluation of Drip Irrigation Emitters Distributing Primary and Secondary Wastewater Effluents

Drip irrigation is a reliable and efficient way to deliver water to the soil; however, drip emitter clogging is a major concern when irrigating treated wastewater. Four types of drip irrigation emitters from three manufacturers were analyzed over a one-year period to monitor the incidence of clogging and its effect on irrigation uniformity. A controlled laboratory experiment was conducted using two different types of pressure compensating emitters designed for reclaimed wastewater, one type of non-pressure compensating emitter designed for reclaimed wastewater, and one type of non-pressure compensating agricultural emitter designed for potable water applications. Emitters of each type distributed tap water, primary treated septic tank effluent, and secondary treated sand filter effluent. Emitter flow rates were measured each month to identify clogged or flow restricted emitters. Some clogging was seen in each type of emitter over the course of the experiment and emitter flow rates fluctuated over time, suggesting that clogging was gradual and often incomplete. Many of the emitters exhibited a cyclical flow rate indicating that clogging was reversible. The emitters distributing septic tank effluent exhibited the most significant reduction in flow. The most severely clogged emitter experienced a reduction of 63% after one year of irrigation with septic tank effluent. Secondary treatment using the sand filter showed the least clogging in all four types of emitters. One of the reclaimed wastewater emitter types experienced an average reduction in flow of 1% while the other two actually increased in flow by1% and 4% after one year of irrigation with effluent from a sand filter. Water quality appeared to have a more pronounced effect than did emitter type. The effect of wastewater type on emitter discharge was +3.3% for tap water, -9.4% for septic tank effluent and -0.3% for effluent from secondary sand filtration. While the agricultural drip emitters experienced a significant negative impact after one year of operation the three drip emitters designed for distributing septic tank effluent and reclaimed wastewater showed little clogging and a high degree of uniformity.

Economic Analysis of Poorly Sited Septic Systems: A Hedonic Pricing Approach

Proper design and quality of soil play an important role in the functioning of soil-based septic systems. Septic systems with traditional leach fields are not suitable for treatment of domestic wastewater in Ohio due to shallow soils. Along with other adverse health effects, untreated or partially treated wastewater could lead to a loss of property valuation. The assessed value of 549 randomly selected properties in Licking County, Ohio was analysed using hedonic pricing method to isolate the effect of poor site selection on the value of the properties. Results indicate that properties sited on soils that are deemed optimal for wastewater treatment are valued 6.2% to 6.8% higher than those sited on sub-optimal soils. The results from this study can help the property owners in making better private decisions regarding installation of septic systems, but can also guide policy decisions that affect public health and common waters.

Design of Delivery Device for Chlorine Dioxide Disinfection

Onsite wastewater management systems with irrigation are affordable and they are also easy to operate. Distribution of wastewater in public places such as lawns, parks, and golf courses is a common feature in wastewater reuse systems. However, it poses a health hazard to the public and people that are exposed to the irrigated wastewater when it is not adequately disinfected. This results in spread of infectious waterborne diseases such as gastroenteritis, cryptosporidiosis, and giardiasis.

REMOVAL OF BUTTERFAT COD AND BOD5 IN INOCULATED SAND COLUMNS

The purpose of this work was to investigate the feasibility of biodegradation of butterfat using an aerobic sandcolumn system. The columns were inoculated with lipolytic microorganisms to colonize the sand with an active biofilm. Butterfat was fed daily to the columns in artificial wastewaters that were supplemented with a surfactant or a detergent. Columns exhibited physical infiltration, trapping butterfat in the sand and resulted in an apparent high degree of COD and BOD5 removal from the effluent. The average BOD5 removal was 50% for the sand columns receiving butterfat and detergent formulation, 36% for the columns receiving butterfat and surfactant formulation, and 57% for the columns receiving butterfat only. Biodegradation of trapped butterfat in the absence of a surfactant or detergent formulation was slow and incomplete. Sand columns receiving artificial wastewater containing butterfat supplemented with detergent showed superior performance in terms of COD and BOD5 removal efficiencies measured for effluent samples. The highest COD removal of 14% from the entire system was achieved by feeding with butterfat and detergent formulation. Accumulation of biomass on the sand grains was monitored by measurement of ATP. Supplemental detergent formulation increased biomass accumulation in the sand columns, suggesting improved contact between the microorganisms and the butterfat substrate.

Ensuring safe reuse of residential wastewater: Reduction of microbes and genes using peat biofilter and batch chlorination in an on‐site treatment system

A batch chlorination system was optimized for on‐site wastewater treatment and reuse system (OWRS) and its efficiency was evaluated for reducing viruses, protozoa, bacteria and antimicrobial resistance in cold and warm seasons.