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Item Selecting filter media for phosphorus removal at the Ennis National Fish Hatchery three-stage subsurface flow treatment wetland(Montana State University - Bozeman, College of Engineering, 2017) Wallis, Jack Enoch; Chairperson, Graduate Committee: Otto Stein; Otto R. Stein, Christopher R. Allen and Ellen G. Lauchnor were co-authors of the article, 'Selecting wetland media for phosphorus removal' submitted to the journal 'Water science and technology' which is contained within this thesis.In western Montana, phosphorus is one of the most common contaminants found in rivers and streams, threatening the health of aquatic ecosystems. In response to growing water quality concerns and new regulatory requirements, a three-stage treatment wetland was recently constructed at the Ennis National Fish Hatchery to treat wastewater generated by raceway cleaning operations. Currently only the first two stages of this system are complete and over the first two months of operation have removed over 98% of influent chemical oxygen demand, 99% of total suspended solids, 59% of total nitrogen, and 95% of total phosphorus. However, the effluent phosphorus concentration is expected to increase as organic matter accumulating in the wetland mineralizes and the phosphorus adsorption capacity of the wetland media is saturated. To maintain long-term phosphorus removal, the treatment wetland was designed with a filter unit to be filled with media capable of adsorbing large quantities of phosphorus. The purpose of this research is to choose the optimal media for this filter unit, comparing three manufactured materials (lightweight aggregate, juniper biochar, and lodgepole biochar) and four natural materials (limestone, dolomite, shale, and gravel). Batch adsorption experiments were conducted with coarse media in deionized water, coarse media in Blaine Spring Creek water, and fine media in deionized water. The difference between these batch experiments showed that water chemistry and particle size significantly affect phosphorus adsorption for a given material. Based on their high performance in batch experiments, lightweight aggregate and lodgepole biochar were tested in continuous flow columns, along with gravel to provide a baseline performance comparison. Gravel and lightweight aggregate removed more phosphorus in continuous flow columns than in batch experiments, likely due to ongoing precipitation with calcium ions in the influent. Lightweight aggregate was the top performing media in all experiments, and is recommended for use in the filter units at the Ennis National Fish Hatchery treatment wetland. Based on its phosphorus removal capacity in column experiments (1200 mg P kg -1 lightweight aggregate), the filter beds will be saturated in 14 months if the current effluent phosphorus concentration of 2.3 mg L -1 is maintained.Item Hydrologic influence of wetland restoration : the Story Mill case study(Montana State University - Bozeman, College of Engineering, 2016) Deford, Lillian Bell; Chairperson, Graduate Committee: Joel CahoonThe Story Mill Wetland is a 20 hectare restoration project in Bozeman Montana, intended to help improve the quality of surface water that leaves the city. The streams that border the property, Bozeman Creek and the East Gallatin River, exceed the Montana Department of Environmental Quality's (MTDEQ) water quality standards for nitrogen (0.27 mg/L) and phosphorus (0.08 mg/L). Wetlands in the landscape have become more intriguing in the advent of MTDEQs adoption of Circular DEQ-13, a legal framework for nutrient trading to achieve improved watershed water quality. Earth-work took place in Summer/Fall 2014, including excavating 5,800 m 2 of disconnected floodplain, and filling a surface drain. The research objectives were to quantify the impacts of the restoration so as to make inferences about the short-term changes in groundwater/surface water interaction, wetland volume and area, and the wetland's impact on the water quality in the bordering streams. Measurements of groundwater levels and surface water flow rates, and water chemistry analyses for both water sources, were recorded weekly from 30 shallow wells and 5 stream gauging stations from August 2014 through September 2015. Groundwater velocity and hydraulic residence time were estimated by performing slug tests in several groundwater wells. Spatially normalized wetland area and volume were calculated based on interpolated groundwater surfaces. Throughout the monitoring period, in all surface and groundwater samples, total nitrogen never exceeded 3 mg/L, averaged 0.76 mg/L, and almost always exceeded the target standard for the East Gallatin River. Total phosphorus was below the detection limit in 97% of all samples and never exceeded 0.22 mg/L. Neither average nutrient concentrations nor pH showed significant general temporal trends, while dissolved oxygen decreased over time. Changes in hydrology were generally localized near earth moving activity. Overall, wetland volume decreased slightly and wetland area increased slightly. Hydraulic gradients showed the primary flow of groundwater to be out of the wetland, with an average soil water velocity of 0.11 m/day. The slow moving groundwater in the wetland system appears to limit the extent of groundwater/surface water interaction, and hinders the role of the wetland in enhancing the water quality in the receiving creeks.Item Ammonia oxidation by a nitrifying community containing novel ammonia oxidizing archaea(Montana State University - Bozeman, College of Engineering, 2014) Olson, Andrew Jared; Chairperson, Graduate Committee: Anne CamperThe disinfection properties of chlorine have long been known. These properties have been leveraged in the disinfection of drinking water. However, in the presence of organic matter, chlorine can form potentially carcinogenic disinfection by-products (DBPs). As a result, the U.S. Environmental Protection Agency promulgated the Stage I and Stage II Disinfectants/Disinfection By-Products Rules, limiting the amount of DBPs that can be present in a distribution system. An economical solution for many drinking water utilities to meet these new regulations was to use to chloramine as a secondary disinfectant. However, chloramines are not without their own disadvantages: free ammonia is added during chloramine formation and released by chloramine decay. This free ammonia can then be used as an energy source by indigenous microoganisms during nitrification. Nitrification can have deleterious effects on drinking water such as decreased disinfectant residual, pH, dissolved oxygen, and alkalinity, as well as an increase in nitrite, nitrate, and heterotrophic bacteria. This study uses effluent from a nitrifying reactor simulating premise plumbing to quickly establish a nitrifying community in glass bead packed bed reactors. Importantly, ammonia oxidizing archaea have been identified in both systems while no known ammonia oxidizing bacteria have been found. Once this nitrifying community was established, the reactors were used as batch reactors with effluent recycle to measure ammonia oxidation during a two hour batch phase. A least squares regression analysis was performed to generate the kinetic constants v max and K m for the nitrifying community in the packed bed reactors. v max was calculated to be 2.23 hr -1. K m was calculated to be 2.35 mg L -1. This work will aid in the effort to characterize the nitrifying population in a premise plumbing system and mitigate nitrification in drinking water.Item Kinetics of biofilm growth and substrate uptake in model drinking water systems(Montana State University - Bozeman, College of Engineering, 1998) Butterfield, Phillip WesleyItem Modeling chlorine concentrations in municipal water systems(Montana State University - Bozeman, College of Engineering, 1985) Murphy, Scott BrianItem Ammonia removal from recycled fish hatchery water(Montana State University - Bozeman, College of Engineering, 1972) Braico, Robert Dodd