Impact of simulated wildfire on disinfection byproduct formation potential

Abstract

Wildfires are complex phenomena that have served a vital role in ecosystem function for millennia. However, thermal alterations to dissolved organic matter's (DOM) solubility and chemical features can change disinfection byproduct (DBP) formation dynamics. Physicochemical changes to DOM are influenced by several factors, the most prominent being heating temperature. In this study, mineral soil samples were collected from fire-prone areas, artificially heated in a muffle furnace to simulate wildfire heating, and leached. As heating temperature increased, chloroform and dichloroacetic acid yields decreased and increased, respectively. Of particular interest was the stimulation of dichloroacetonitrile, a highly toxic and unregulated DBP, at moderate heating temperatures. To demonstrate further insight into the chemical attributes of wildfire-impacted DOM, optical properties were used as proxy measurements. This work provides water utilities with information on how wildfires can alter DBP formation potential, and a means to investigate correlations between intrinsic optical measurements and DBP yields.

A review of simulation experiment techniques used to analyze wildfire effects on water quality and supply

“…Post-fire runoff DOM response varies widely across studies, from slight decreases in concentration to levels in the 95 th percentile of pre-fire conditions 1,10,13,28,43,60,[83][84][85] . Downstream, DOM is the main substrate in the formation of carcinogenic disinfection byproducts (DBPs) during the chlorination stage of water treatment 60 .…”

“…Post-re runoff DOM response varies widely across studies, from slight decreases in concentration to levels in the 95th percentile of pre-re conditions. 1,10,13,28,43,60,[83][84][85] Downstream, DOM is the main substrate in the formation of carcinogenic disinfection byproducts (DBPs) during the chlorination stage of water treatment. 60 Elevated levels can require water treatment plants to implement expensive alternate disinfectants, precursor (i.e., DOM) and DBP removal strategies, or even force them to shut down.…”

“…Limited information exists about post-wildfire water quality response, in particular, with most studies primarily focusing on DOM and nutrients-leaving the responses of microbial constituents and more novel contaminants largely unknown 23 . Laboratory-and plot-scale simulation experiments which replicate burning and combustion mechanisms present in natural wildfires, as well as raindrop kinetic energies and leaching effects similar to post-wildfire precipitation, offer an alternative analytical technique for estimating wildfire effects on water quality and supply 2,7,[24][25][26][27][28] . Hereafter, these two types of simulation experiments will be referred to as wildfire and rainfall simulators, respectively.…”

“…23 Laboratory-and plot-scale simulation experiments which replicate burning and combustion mechanisms present in natural wildres, as well as raindrop kinetic energies and leaching effects similar to post-wildre precipitation, offer an alternative analytical technique for estimating wildre effects on water quality and supply. 2,7,[24][25][26][27][28] Hereaer, these two types of simulation experiments will be referred to as wildre and rainfall simulators, respectively. These studies primarily advance understanding of burn effects on small-scale soil and water physical and chemical properties.…”

Impact of simulated wildfire on disinfection byproduct formation potential

“…In Wilkerson and Rosario‐Ortiz (2021), the author contributions information was missing in the original published article. The Author Contributions section is provided below:…”