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Coal
Published in Karlheinz Spitz, John Trudinger, Mining and the Environment, 2019
Karlheinz Spitz, John Trudinger
CBM-produced water is pumped in large volumes from the coal seams to the surface to release the gas trapped in the coal seams. It can be discharged to the land surface, to surface water, stored in evaporation ponds, used for stock or wildlife watering, re-infiltrated, injected back into the aquifer, or treated for various uses. Without treatment, its discharge may have significant impacts on water quality. CBM-produced water commonly contains dissolved salts, suspended solids, sodium, fluoride, chloride, ammonia, and metalsat concentrations higher than those of the receiving waters. The sodium adsorption ratio (SAR) is the ratio of the sodium ion concentration to the combined concentrations of calcium and magnesium ions in water. Water with high SARs can cause soils to become dispersed, less permeable (resulting in reduced plant growth) and more prone to erosion; such waters may not be appropriate for irrigation. High levels of soil salinity, resulting from irrigation with some CBM-produced water can reduce crop yields. The cumulative effects of CBM-produced water on agricultural soils and crop yields, and the factors that influence those effects are not completely understood. Hydrologic changes resulting from CBM operations may adversely affect fisheries; the nature and extent of those effects, however, are largely unknown. Coal seam dewatering can also affect the shallow groundwater table, impacting shallow bores, springs and domestic wells.
AFO/CAFO Siting: Physical Factors
Published in Frank R. Spellman, Nancy E. Whiting, Environmental Management of Concentrated Animal Feeding Operations (CAFOs), 2007
Frank R. Spellman, Nancy E. Whiting
Sodium adsorption is represented by the sodium adsorption ratio (SAR), the measured amount of sodium relative to calcium and magnesium in a water extract from a saturated soil paste. A high or moderate SAR, more than 4, interferes with the ability of the plant to absorb water from the soil and to exchange plant nutrients. This interference reduces plant growth and seed germination and limits the choice of crops that can be successfully grown. A SAR of more than 13 has a detrimental effect on soil intake, permeability, and structure.
Assessment and Management of Drainage Water Quality for Reuse in Irrigation Projects
Published in Smart Science, 2021
Abdul Khider Aziz Mutasher, Riyadh Jasim Mohammed Al-Saadi, Fadhil M. Al-Mohammed
The ‘Sodium Adsorption Ratio’ (SAR), affects the normal rate of water infiltration in the soil, and therefore it can be considered one of the most important factors in assessing water quality for irrigation. This ratio can be found according to the following equation: -
Hydrogeochemistry and quality assessment of groundwater in Jinghui canal irrigation district of China
Published in Human and Ecological Risk Assessment: An International Journal, 2020
Yan Zhang, Yuqing Xiong, Yang Chao, Ruirui Fan, Feier Ren, Bin Xu, Zhao Liu
The sodium adsorption ratio (SAR) is the most popular metric to determine the suitability of water for irrigation. It can be calculated by the following equation (Richards 1954): where all ions are represented in meq/L.
Ionic composition, geological signature and environmental impacts of coalbed methane produced water in China
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2021
Chen Guo, Yong Qin, Dongmin Ma, Yucheng Xia, Yue Chen, Qinghong Si, Lingling Lu
The Sodium Adsorption Ratio (SAR) is a measure of water quality for use as irrigation water. SAR is calculated using Equation (4), where Na, Ca, and Mg are in units of meq/L: