Erosion is a natural process that occurs when soil particles are detached from one site and transported to another by water or wind, and can occur naturally or be accelerated by humans. Sediment can cause direct mortality or reduce growth of fish and other aquatic resources, particularly larval fish and eggs. Three treatments consisting of compost and jute netting, crimped straw with native seeds, and jute netting and vegetation filter strip were used to evaluate loss of runoff water and sediment on steep slopes. Erosion plots were built on slopes of 27 percent and filled with soil. The treatments were applied in triplicate and irrigated at 14-day intervals. Each erosion plot was irrigated with approximately 79 gallons of water for 10 hours and runoff was collected in pre-weighed containers during each period. After each collection, runoff from each plot was measured and recorded by subtracting the weight of each empty container from the combined weight of water and sediment. Turbidity, pH, and electrical conductivity were measured, and the separate weights of runoff and dry sediment were determined. The combination of jute netting over a layer of commercially available compost was over 99 percent effective at reducing runoff and sediment loss as compared to the untreated control erosion plots. Jute netting combined with a vegetative filter strip of creeping wild rye was over 94 percent and 99 percent effective at reducing runoff and sediment loss when compared to the untreated control erosion plots, respectively. Runoff and sediment loss from plots treated with crimped straw and native seeds was significantly greater than that of the other treatments, yet this treatment was over still 80 percent effective at reducing runoff and nearly 97 percent effective at reducing sediment loss. The cost-effectiveness of each treatment was evaluated based on the cost of the total treatment compared to the amount of water each treatment prevented from leaving the site, using the control plots as a baseline. The combination of jute and vegetation filter strip cost approximately $0.47 per liter of water prevented from leaving the site and was almost as effective at reducing runoff and sediment loss as was jute combined with compost, which cost $1.04 per liter. While each of the three treatments significantly reduced runoff and sediment loss when compared to the barren control plots, the jute and filter strip treatment was the most cost-effective of the three treatments. All treatments were effective at decreasing runoff and sediment loss when compared to the control, though no significant difference in runoff was observed between the control and any of the treatments after ten weeks. Thus, erosion control BMPs should be implemented well before the first storm causing runoff in order to be most effective.

No / Laboratory scale model slopes reinforced with waste carpet fibers were made in a rigid tank with dimensions of 800 mm x 300 mm x 500 mm. Bearing capacities of the strip footing rested on non-reinforced and fiber-reinforced model slopes with 1%, 3% and 5% fiber content were compared at 20% footing displacement ratio. The influence of location of footing on the bearing capacity was studied with placing the footing at different edge distances from the crest of the footing (i.e., 150 mm, 100 mm and 0). Suction probe sensors were installed at appropriate locations on the rear side of the model slope to measure the pore-water pressure generated due to the footing pressure. Results showed that fiber reinforcement increased the bearing resistance of the model slopes significantly. Inclusion of 5% fiber increased the bearing resistance by 271% compared to that of non-reinforced model slope at the footing edge distance ratio of 3. The location of footing was found to affect the load-carrying capacity of the fiber-reinforced model slope. The increase in the edge distance ratio of the footing increased the load-carrying capacity of the model slope.

Years of intensive tillage operations and heavy winter rainfalls have taken a toll on the soils in the Mississippi Delta causing compaction and nutrient losses due to runoff. The purpose of this research was to determine the effects of tillage systems and P and K fertilizer placement methods on corn and soybean production, as well as soil properties in the Mississippi Delta. The tillage treatments included conventional tillage, conventional tillage with subsoiling, and strip-tillage. The fertilizer placement treatments included a non-treated control, incorporated with tillage, and broadcast after tillage. Strip-tillage treatments reduced soil compaction and maintain nutrient levels while improving or maintaining yields in both crops. A more long term study is needed to determine if incorporating fertilizer with tillage will impact crop yields.

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In recent years, fierce competition, rising production costs and depressed prices for mineral products, have forced mining companies to find ways to improve efficiency and lower production costs. Given the fact that loading and hauling operations account for up to 60 % of the total costs in surface mining, the optimization and control of these operations can provide substantial reductions in the costs. Assignment of truck to shovels has been traditionally performed by fixed truck allocation and by truck dispatching. Several operations research and simulation techniques, which can be used to solve problems concerning surface mining operations, are discussed. The types of problems addressed are: how to allocate trucks to loading equipment, how to evaluate the performance of an existing operation, and how to predict the performance of a future system. For truck allocation, operations research methods such as: dynamic programming, integer programming, and heuristic algorithms are discussed. These methods are used mainly for decision making purposes. Queuing theory techniques, also analyzed, are used mainly for evaluation purposes. / Master of Science