Laboratory Studies on The Effect of MSW Leachate on Soil by Using One-Dimensional Soil Column Method

To understand the soil-pollutant interaction geo-environmental engineer design a hydraulic barrier to control the transport of pollutant through the soil and minimize the pollution of affecting the soil properties. Hence, in this study one-dimensional soil column method was stimulated similar to the field conditions. The extraction of leachate from the municipal solid waste was manipulated based on the annual precipitation data. The test result showed that the concentration of extracted leachate was increased up to 45 days and slightly decreased by increasing the addition of water. The interaction of extracted leachate changes the soil characteristics (i.e., increasing tendency by period). The result showed that the LL and PL of the soil was increased by increasing the addition of leachate. The UCS was increased from 167.80 kPa to 176.54 kPa up to 75th days and then decreased gradually at 95th to 105th days. Conversely, hydraulic conductivity was decreased at the initial stage and then gradually increased at the end of the experiment. These changes in the soil characteristics are mainly due to the alters of soil particles into dispersive structure with more effective pore space, which reduces the soil strength and increases the permeability value.

Development of a municipality index of environmental pressure in Campania, Italy

The Experimental Zooprophylactic Institute of Southern Italy (Istitituto Zooprofilattico Sperimentale del Mezzogiorno, IZSM) is a public health institution operating within the Italian National Health Service. Over the past 5 years [IZSM] has promoted several research studies and interventions in an effort to tackle the ‘Land of Fires’ phenomenon, caused by the continued trafficking and uncontrolled incineration of waste that has affected some areas of Campania for decades. In this article, a mathematical model that generates a municipality index of environmental pressure is presented. The model was developed by a multidisciplinary team led by an environmental engineer and included researchers in the fields of veterinary and human medicine, biology and computer science. This model may serve as a geostratification tool useful for the design of human biomonitoring studies, although it may also be employed for strategic planning of remediation programs and public health interventions.

Disciplinarity and Literate Activity in Civil and Environmental Engineering: A Lifeworld Perspective

Too frequently, representations of disciplinary writing foreground static notions of knowledge creation and literate practice in science and engineering. Rooted in discourse community theory, such representations present normative tropes of scientific practice that background notions of disciplinarity and obscure people’s lived experience and practice. Drawing on a case study of one woman, a civil and environmental engineer, this article argues for a lifeworld perspective of disciplinary becoming: a perspective that foregrounds notions of disciplinarity, lived experience, and literate practices as constantly mobile and in flux. The study suggests, specifically, that the woman’s work as an engineer cannot be separated from the people with whom she works, or has worked, and that her development as a writer extends beyond typical accounts of disciplinary enculturation. The author concludes by offering implications of this research for studies of disciplinarity and school science.

Of Time and the Wetland

At the oldest of Arcata’s treatment wetlands, it’s now possible to walk on water. Over three decades of filtering sewage, Arcata’s wetland cells have developed floating mats of dead cattail stems and leaves underlain by living roots, resilient enough to support a person’s weight. The short journey across Treatment Wetland 3 is a strange experience, like walking on a soggy trampoline. Water seeps through the cattail mat and into footprints. On a February day, a dense maze of brown cattail stems stretches twelve feet above the wetland’s surface, their shaggy brown seedheads waving in the breeze. A stroll across the treatment wetland is as close as a modern American can hope to get to the feel of the floating tule islands that William Finley camped on in the upper Klamath Basin in 1905, and that crowded California’s unspoiled marshes before the Gold Rush. The floating mats in Arcata were created by accident when the city’s treatment plant operators increased the depth of the treatment marshes, part of an effort to improve their declining performance. To their surprise, the dense growth of cattail rose off the bottom and continued to thrive, roots dangling in the water. The wetlands have aged. “Arcata’s is the grandmother municipal treatment wetland,” says David Austin, an environmental engineer with CH2M Hill who specializes in treatment wetlands design. Austin remembers studying the Arcata wetlands as a student at University of California at Davis in the 1990s. “It was a pioneering system. Now it’s an old design— one that wouldn’t be used today.” In 2016, three decades after Bob Gearheart’s unconventional marshes began cleaning Arcata’s sewage, the city’s wastewater plant faced a crisis. During the cold rains of winter, the system often failed to perform to the standards set in its discharge permit. Every part of the plant had aged to the point where its performance was in decline. At the headworks, the two giant Archimedes screws that push raw sewage uphill through a coarse screen had been running for decades; their metal housings were rusting away.

Do- It- Yourself Wetlands

Bob Gearheart emerged as Arcata’s marsh guru during the city’s long battle with the state water bureaucracy. This unpaid post demanded that Gearheart crank out proposals for wetland treatment at a frenetic pace, knowing that the city’s financial future depended on his work. He wore a smile, energized by the pressure. Gearheart’s son, Greg, grew up to become an environmental engineer working for the state water board. He earned his engineering degree at Humboldt State, studying with his father. He remembers his dad happily engaged during the battle for Arcata’s alternative treatment system, at the same time he was teaching a full load of classes. “My dad likes a fight,” Greg says. “He adapts well. People put an obstacle in front of him, and he figures out a way to make it look like it’s not really a problem. He makes it look like it was stupid on his opponent’s part to put the obstacle there.” In 1977, the elder Gearheart proposed a first: a wetland built to treat municipal wastewater to the standards required under the Clean Water Act. He possessed a serene certainty that he could make this untried system work. “I had no data until we did the pilot study,” he remembers, “but I was one hundred percent confident.” The power of aquatic plants to cleanse polluted water had first been tested in the 1950s by Käthe Seidel, a researcher at the Max Planck Institute in Germany. She showed that while some wild plants were killed off by waters tainted with phenol—a toxic organic compound used in making plastics—others had a remarkable ability to adapt. At first contact, effluent containing phenol caused bul­rush stems to wither away, but the roots survived and in time sent up healthy new shoots. Bulrush, it turned out, could break down phenol, metabolizing it into the amino acids that build protein. The plant also thrived in domestic sewage. Seidel used carefully groomed cultures of wetland plants, rooted in beds of gravel or sand through which effluent flowed.