Papers by Omar M Al-Qudah
Journal of Arid Environments, 2015
The study investigates how water chemistry evolves as ephemeral stream runoff is formed through t... more The study investigates how water chemistry evolves as ephemeral stream runoff is formed through the interaction of sediments and precipitation in the Amargosa Desert region and by analogy other desert regions. In this study, thirty lysimeters were installed in the major arroyos in the Amargosa Desert to capture runoff water. The sampling process included sediment, precipitation, and runoff water chemistry. Innovative and low cost methods were used to measure the chemical composition of the resulting runoff and examined some of the important processes affecting the runoff chemistry. Results of the analytical and statistical analyses indicate that runoff salinity is low as a result of net salt accumulation in sediments. Chemical behavior between precipitation and runoff is classified as leached (TDS,
Earth and Space Science, 2016
Nitrogen (N) fertilizer applications have resulted in widespread groundwater nitrate-N (NO 3-N) c... more Nitrogen (N) fertilizer applications have resulted in widespread groundwater nitrate-N (NO 3-N) contamination in the U.S. Corn Belt. Goodwater Creek Experimental Watershed (GCEW) is an agricultural watershed in the claypan soil region of northeastern Missouri with a network of 96 wells at depths of 2.7-15.7 m. The objectives of this study were to (1) inspect the spatial and temporal variations of NO 3-N concentrations in GCEW's groundwater, particularly with well depth at scales ranging from individual well, well nest, and field to the entire watershed during the period 1991 to 2004; (2) understand the processes controlling the variability of NO 3-N concentrations in groundwater at various scales within GCEW; and (3) compare groundwater NO 3-N concentrations in GCEW to other agricultural watersheds in the U.S. Nitrate-N concentrations were determined in more than 2000 samples collected from 1991 to 2004. Despite the low hydraulic conductivity of the claypan soils, considerable NO 3-N contamination of the glacial till aquifer occurred, with 38% of the wells exceeding 10 mg L À1. Groundwater recharge by preferential pathways through the claypan appeared to be the primary mechanism for NO 3-N movement to the aquifer. Changes in concentration with depth steadily increased to 8.5-10 m and then decreased with further depth. This pattern was consistent with decreased hydraulic conductivity in the Paleosol layer at 8.5-10 m, denitrification below this layer, and mixing of recent contaminated water with older uncontaminated water in the lowest strata. Only 19-23% of sampled wells exceeded 10 mg L À1 in nonclaypan agricultural watersheds over the continental U.S., suggesting that groundwater in GCEW was more susceptible to NO 3-N contamination than nonclaypan watersheds. These results demonstrated that preferential flow through the soil and hydraulic conductivity of the subsurface strata controlled NO 3-N transport in this claypan watershed.
This report was prepared by the Nye County Nuclear Waste Repository Project Office, pursuant to a... more This report was prepared by the Nye County Nuclear Waste Repository Project Office, pursuant to a Cooperative Agreement funded by the U.S. Department of Energy, and neither Nye County nor any of its contractors or subcontractors nor the U.S. Department of Energy, nor any person acting on behalf of either, assumes any liabilities with respect to the use of, or for damages resulting from the use of, any information, apparatus, method, or process disclosed in this report. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the U.S. Department of Energy or Nye County. The views and opinions of authors expressed herein do not necessarily state or reflect those of the U.S. Department of Energy.
Natural tributaries in arid regions are generally ephemeral occurring only during the generally s... more Natural tributaries in arid regions are generally ephemeral occurring only during the generally short and isolated thunderstorms. Thus, sustained flow is rare and baseflow is essentially absent, large volumes of surface runoff water move into the channel within a short period causing flash floods that are characteristic of arid-zone drainage basins. However, the studies of Amargosa Desert regional groundwater indicate that infiltration of surface runoff occurs in the arroyos subsequent to runoff producing storms and that this infiltration represents a large portion of the groundwater recharge. Sampling of surface runoff in a desert environment from ephemeral arroyos is complicated by a number of practical concerns. Surface runoff events are uncommon, difficult to forecast in advance and sometimes separated by gaps of more than a year. In the absence of very large sources of funding, any desert arroyo surface runoff system requires compromises. This research, as part of the Nye Count...
Medical waste is an essential part of the municipal waste management, and is categorized as hazar... more Medical waste is an essential part of the municipal waste management, and is categorized as hazardous waste. Unfortunately, in practice in Jordan this waste is taken as general waste and thus treated as any other waste and this create many dangers to the persons whose deal these wastes and to the environment as the same time. This study comes to understand and to issue solutions for the previous big problem through collect actual data and facts regarding wastes (specially medical wastes) generated at the Healthcare Establishments (HCE) located in Amman City (in Jordan) Also, to approve the effectiveness of the incineration treatment method for the solid waste (especially medical waste) based on experimental analysis for the emission gases and the reminder ashes from an incinerator located at University of Jordan hospital. And then make a comparison between the results that obtained and the reported results in the literatures. Field investigations of hospitals, medical laboratories, ...
Spatial and temporal variations of nitrate concentrations in groundwater at Goodwater Creek Exper... more Spatial and temporal variations of nitrate concentrations in groundwater at Goodwater Creek Experimental Watershed were examined to understand the controls of nitrate transport in groundwater. The 75-km2 watershed is dominated by a continuous, restrictive clay layer 20-50 cm beneath the top soil. The mean nitrate-N concentration of the 94 wells located throughout the watershed was 12 mg L-1 from 1991 to 2004, which is comparable to the mean value in shallow groundwater at agricultural watersheds with well-drained soils throughout the US. The temporal variation of nitrate-N concentrations from 1991 to 2004 was dominated by three patterns among 94 wells: no obvious trend, an increasing trend and a decreasing trend. The variation of nitrate-N concentrations with well depth was dominated by a bulge-shape: increasing with depth above 10 m but decreasing below it. This threshold depth is consistent with a continuous glacial till layer located at the same depth, which has much higher hydra...
Responses of stream flow hydrograph to intense rainfall events in small basins were previously in... more Responses of stream flow hydrograph to intense rainfall events in small basins were previously investigated using a dimensionless theoretical model based on Darcy’s law, which is expressed by a ratio of runoff to peak runoff as a function of time and a time-constant that represents the Darcian response to sharp rainfall-driven pulses on the head of the shallow groundwater system. In this study, the model was applied to a 72 km2 claypan watershed, Goodwater Creek Experimental Watershed (GCEW) in central Missouri, to understand how the claypan soil affects the response of stream hydrograph to rainfall events. Results from a number of storms ranging from 11 to 129 mm d-1 showed that the time-constant is about 1.3 days. Comparing to the previous studies, this value is comparable to that in the Ozark aquifer in southwest Missouri (1.5 days), but significantly greater than that in Meramec River, karst spring, and Big River, with 0.5, 0.4, and 0.14 days, respectively, where soils are drama...
ABSTRACT Old Settlers Creek in the City of McKinney was pre-selected by the City of McKinney - De... more ABSTRACT Old Settlers Creek in the City of McKinney was pre-selected by the City of McKinney - Development Services/Engineering (DSE) and Texas AgriLife Research for a stream restoration project as thecreek had faced head cutting and some bank erosion due in part to the increased development in the creek watershed and additional stormwater runoff from adjacent streets. In addition, the site is very visible with high potential for successful restoration. The evaluation process for this stream was undertaken by DSE and Texas AgriLife based on Watershed Assessment for River Stability and Sediment Supply (WARSSS) procedures (Rosgen, 2006), and this included a reconnaissance level assessment, a sediment and stability consequence assessment, and a prediction level assessment. A restoration plan has been developed based WARSSS, Old Settlers Creek profile and cross sectional survey, and a Reference Reach’s (Timber Creek) morphological parameters. Design procedures involved designing a stable cross section and profile including bankfull, pool to pool and riffle to riffle spacings,slope, and other geomorphological features. Other tasks performed in this study are: • Selection of appropriate stabilization structures (cross vanes) • Developing a planting plan • Developing a construction sequence and erosion control plan • Calculation of shear stress and flood studies for design check. The report includes, 1) Old Settlers Creek field survey (existing conditions; cross section survey; and profile survey), and its hydrology calculations (drainage area; rain intensity; flow rate; and flow velocity); 2) Timber Creek (the reference reach) field survey (profile survey; cross section survey; pattern survey; and pebble count), in addition to its hydrology calculations; and 3) the designing procedures listed above.
The sequence of policy decisions that has surrounded the public debate over the management of the... more The sequence of policy decisions that has surrounded the public debate over the management of the nation’s accumulating stockpiles of radioactive waste has not left any alternative strategy, other than geologic burial at Yucca Mountain, Nevada, to deal with the problem. Policymakers and nuclear power plant owners virtually aborted all other options and any new ideas before they were born, and then they downplayed the scientific issues and made no effort to consider alternatives other than the Yucca Mountain site, so that ultimately the only sound that was heard was the political sound. The Nuclear Waste Policy Act of (NWPA) 1982 represented a political, rather than scientific response, to the nation’s nuclear waste dilemma by decreeing that geologic burial of nuclear waste was the only solution available. The amendments to that Act adopted in 1987 further restricted options by deciding that Yucca Mountain would be the only site considered for a high-level radioactive nuclear waste (...
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Papers by Omar M Al-Qudah