Produced Fracking Water Disposal in California Inputs Selenium and Arsenic in Surface Acquifers.

[NNadir]

Regrettably I can't spend much time with this paper here: Historic and Contemporary Surface Disposal of Produced Water Likely Inputs Arsenic and Selenium to Surficial Aquifers, Robert J. Rossi, Rebecca A. Tisherman, Jessie M. Jaeger, Jeremy Domen, Seth B. C. Shonkoff, and Dominic C. DiGiulio Environmental Science & Technology 2023 57 (19), 7559-7567

Text from the introduction:

California was historically, and is currently, one of the largest oil and gas producing regions in the conterminous United States (U.S.). (1) Oil and gas development generates sizable volumes of wastewater (produced water) by extracting waters contained within source formations and/or water used to enhance hydrocarbon recovery, and these waters are known to contain many organic and inorganic contaminants. (2) Multiple strategies have been utilized to dispose of the large volume of produced water generated by oil and gas development processes.

In addition to subsurface injection by injection wells (generally the most common disposal method), in California, produced water has also been disposed of in lined and unlined surface impoundments, hereafter referred to as produced water ponds. (3) Unlined ponds dispose of the produced water via both percolation and evaporation. While the frequency of this disposal method has decreased substantially since 2014, (3) produced water ponds have been heavily utilized since the mid-20th century, and recent work has demonstrated impacts to groundwaters near disposal facilities. (3,4)

The largest number of unlined produced water ponds (at least 1470 active, inactive, or closed ponds) (3) are located in the southern portion of the San Joaquin Valley (SJV), one of the most productive agricultural regions in the world. (5) Due to the arid SJV climate, agriculture in this region is heavily reliant on groundwater resources. (6) However, droughts have generally diminished rates of groundwater recharge while pumping demands have simultaneously increased, leading to an overdraft in areas of the SJV. (7) Thus, decreased recharge and the subsequent reduced dilution of produced water in existing groundwater increase the potential for impact to diminishing groundwater resources...

...Arsenic and Se are geogenic contaminants in the SJV and are commonly detected in SJV produced water ponds. Arsenic is sourced from As-rich strata in both the western and eastern margins of the SJV, whereas Se-rich parent materials are generally found in the western and southwestern margins of the SJV. (10) In the 1980s, high levels of Se in agricultural evaporation pond waters caused the high mortality and deformity rates of waterbirds in the SJV. (11) Arsenic is a notorious groundwater contaminant that can increase the risk of cancer and cause other health effects in humans. (12) About 10% of the SJV wells tested between 2008 and 2018 had As concentrations exceeding World Health Organization recommendations. (6)...

Oh well then...

In California, where the overwhelming source of production of electricity for all that electrified "green" stuff is from dangerous natural gas, nuclear power is considered "too dangerous," but gas is just fine.

The picture presented in this paper, again with which I can spend very little time, isn't pretty, particularly given California's involvement with the food supply, not that the constituents who elected Kevin McCarthy give a rat's ass about health or sustainability since it takes away from their efforts to distribute the resources of the middle class to filthy (literally) rich people.

Don't worry. Be happy.

California is very good at producing "aspirational" laws that everyone ignores, particularly because so many of them have "by xxxx" where xxxx is some year in the future when the people passing the law will have retired or be dead.

From the conclusion:

...Despite the enactment of the Sustainable Groundwater Management Act in 2014, (67?69) which aims to combat overdraft in the SJV, groundwater depletion is still occurring. Specifically, Argus et al. (2022) concluded that the southern SJV lost 1.5 ± 0.4 km3 yr–1 during 2006–2021. (70) Similarly, Liu et al. (2022) observed a decrease in groundwater storage (2.55 ± 0.60 km3 yr–1) in the southern SJV over the present drought (2019–2022). (71) Depleted aquifers will be more sensitive to As and Se contaminant fluxes, and during droughts, any As/Se contamination imparted by produced water disposal will unlikely be diluted by mixing with meteoric or surface waters. Additionally, desiccation of shallow aquifers may create subsurface pools of contamination, comparable to current As challenges facing the SJV. (6) During persistent wet periods, pools of legacy contamination could be remobilized and transported to nearby aquifers if recharge waters are undersaturated in respect to As- and Se-bearing minerals. (72)...

Unh Oh... It appears that efforts to contain the arsenic will mobilize the selenium, and maybe even, (gasp!!!!!!) natural uranium in the California rocks through which ground water percolates.

...If contamination plumes were to merge, mixtures of trace metal contamination could prove exceedingly difficult and expensive to address. For example, As, a relatively common water contaminant in the SJV, is generally less mobile in oxic environments. Thus, injecting oxic waters into aquifers could limit the mobility of As species and address potential As contamination. However, we observe that As often coexists with Se in disposal waters, and as such, this strategy may reduce As mobility while simultaneously facilitating Se mobility. Furthermore, as the valley fill sediments of the SJV are well known to potentially contain U, (76) this hypothetical solution may lead to both Se and U mobilization...

Have a nice Sunday.

[pazzyanne]

1. Humans are so stupid!

That is all.