Contaminated area instability along Ångermanälven River, northern Sweden

Abstract

Industrially utilized river basins are frequently exposed to contaminants originating from polluting activities. However, the physical instability and probability of mass movement mobilization of contaminated soil into rivers have only received little attention. In this study, we present a GIS-based method to produce a regional overview of where and how contaminated areas are potentially exposed to slope instability. A landslide susceptibility-index was used to study the degree and distribution of overlap between contaminated sites and unstable ground. A contaminated area instability hazard classification was produced integrating slope instability and contamination risk classification. Our results indicate that mass movement can be tied mainly to a slope gradient ≥16°, a proximity to the river that is <500 m, a distance of <500 m from roads, concave surface curvature, and sand- and silt soils. Forty-six (22%) of all considered contaminated sites are located within areas with a non-negligible slope instability, of which a majority, 30 sites (14%) are situated on ground with a low or moderate instability. Three sites with a class 2 contamination risk (the 2nd highest class) are located on ground with a very high slope instability.

Well Salinization Risk and Effects of Baltic Sea Level Rise on the Groundwater-Dependent Island of Öland, Sweden

“…Presently, 17.5% of all wells on Öland are already located in high-risk areas, according to the results presented in this study. Furthermore, all wells considered in this study had some non-negligible risk of salinization, as reflected by their risk index values being larger than zero.…”

“…Although the approach was not process-based, the empirical risk-index type of relations [16,17] applied here, which considered combined effects of different influential factors, have previously been found [18,19] to show relatively good agreement with data on well salinization caused by seawater intrusion. We used parameters affecting seawater intrusion into wells and freshwater aquifers in coastal areas corresponding to previous work [16]: elevation above sea level, distance to the ocean, distance to lakes, mean annual precipitation and soil type.…”

“…This shows that most wells (64% of all wells) are located in areas with a medium risk of saltwater intrusion (bars 7-14 in Figure 7). Numerous wells reside within the highest-risk-value-index groups (bars [15][16][17][18][19][20][21][22] and in the lowest risk groups (bars 0-6). In the high-risk groups, 604 wells can be found, which account for 17.5% of all wells on the island.…”

Thinking for the future: Phytoextraction of cadmium using primed plants for sustainable soil clean‐up

“…The increase in global surface temperature (+2°C expected according to UN, 2015) will induce change in ice and snow patterns with an impact on the physical and geochemical properties of soil‐groundwater systems (Augustsson et al, 2011). Adding to the temperature change, the increase in annual precipitation (Olsson & Foster, 2014) is expected to facilitate the leaching of heavy metals into the groundwater (Bonten et al, 2012) combined with catastrophic events, for example, landslides of contaminated soil (Ströberg et al, 2017).…”