Geochemical evolution of groundwater in the Mud Lake area, Eastern Idaho, USA

Abstract

Groundwater with elevated dissolved-solids concentrations-containing large concentrations of chloride, sodium, sulfate, and calcium-is present in the Mud Lake area of Eastern Idaho. The source of these solutes is unknown; however, an understanding of the geochemical sources and processes controlling their presence in groundwater in the Mud Lake area is needed to better understand the geochemical sources and processes controlling the water quality of groundwater at the Idaho National Laboratory. The geochemical sources and processes controlling the water quality of groundwater in the Mud Lake area were determined by investigating the geology, hydrology, land use, and groundwater geochemistry in the Mud Lake area, proposing sources for solutes, and testing the proposed sources through geochemical modeling with PHREEQC. Modeling indicated that sources of water to the eastern Snake River Plain aquifer were groundwater from the Beaverhead Mountains and the Camas Creek drainage basin; surface water from Medicine Lodge and Camas Creeks, Mud Lake, and irrigation water; and upward flow of geothermal water from beneath the aquifer. Mixing of groundwater with surface water or other groundwater occurred throughout the aquifer. Carbonate reactions, silicate weathering, and dissolution of evaporite minerals and fertilizer explain most of the changes in chemistry in the aquifer. Redox reactions, cation exchange, and evaporation were locally important. The source of large concentrations of chloride, sodium, sulfate, and calcium was evaporite deposits in the unsaturated zone associated with Pleistocene Lake Terreton. Large amounts of chloride, sodium, sulfate, and calcium are added to groundwater from irrigation water infiltrating through lake bed sediments containing evaporite deposits and the resultant dissolution of gypsum, halite, sylvite, and bischofite.

Evaluation of background concentrations of selected chemical and radiochemical constituents in water from the eastern Snake River Plain aquifer at and near the Idaho National Laboratory, Idaho

“…Factors that may differ among datasets and influence the comparability of the data are water-sample collection methods and field-preservation methods (Knobel and others, 1992), along with different time periods for data collection. Also, the wells used to calculate background concentrations are a combination of several water types and sources collected at different times Rattray and Ginsbach;, Rattray, 2015. Sample collection and methods for analyses for each constituent collected followed USGS or Idaho State Department of Environmental Quality methods that were described in the corresponding report for which the data were collected.…”

“…Because of this, median values of the datasets are used as the upper limit for background for most of the constituents as opposed to maximum concentrations or complex statistical derivations. Busenberg and others (2001); Bartholomay and Twining, (2010); Rattray and Ginsbach, (2014);and Rattray (2015) showed that most of the wells at and upgradient of the INL include a mixture of old and young water and that wells commonly contain a mixture of different types of water. The 5 µg/L line of equal lithium concentration ( fig.…”

“…Groundwater at the INL primarily contains calcium ions from the hydrolysis of calcite and dolomite that make up much of the Paleozoic carbonate rocks comprising much of the mountains and alluvial sediments northwest of the INL (Robertson and others, 1974, p. 62). High concentrations in the Mud Lake area have been attributed to irrigation water infiltrating through sediments containing evaporite deposits and subsequent dissolution of the deposits (Rattray, 2015).…”

“…High concentrations in the Mud Lake area have been attributed to irrigation water infiltrating through sediments containing evaporite deposits and subsequent dissolution of the deposits (Rattray, 2015). Dissolution from sodium chloride in soil and contributions from thermal water also have been suggested as possibilities for high sodium concentrations in the Mud Lake area (Robertson and others, 1974, p. 62).…”

Spring water chemistry in a formerly glaciated area of western Poland: the contribution of natural and anthropogenic factors

“…In the Lubuska Upland area, only 75 % of the rural population has a sewer system (Szablowska et al 2013). However, agricultural contamination of groundwater, which is often underestimated, should also be considered (Jeong 2001;Naseems et al 2010;Abdesselam et al 2013;Rottray 2015). In such conditions, it is necessary to have a reliable system to monitor groundwater quality.…”