Severe environmental pollution by heavy metals can be extremely costly to remediate and insure if it concerns very large-scale and long-term operations. A famous example is cadmium pollution of the Toyama Prefecture (Japan) by mining, causing Itai-Itai disease with softening of bones and kidney failure, taking a century of environmental remediation since 1912. Another example is mercury poisoning discovered in 1956 in Kumamoto Prefecture (Japan), causing the Minamata disease affecting the nervous system, leading to insanity (as from 'mad as a hatter' like the hat making Mancunians working with mercury. Large-scale cleanup and settlement for damages of nearly $100 million only reached completion almost half a century later in 2010. Finally, there is the famous case of the more than 10 years of severe Hinkley groundwater contamination between 1952 and 1965, with genotoxic-carcinogenic chromate, leading to a class action lawsuit (starring Julia Roberts as Erin Brockovich) that was only settled in 1996 for a staggering $333 million.
At RemTech 2020 conference, Duncan Spencer shows what role insurance can play in managing pollution liabilities during remediation projects, inherited, or created during works. It is argued that liability insurance covering risk of larger damages in the order of $100 million is not that readily available, has maximum terms of 5 to 15 years and demands best available remediation strategy, guaranteeing maximum control over spreading of toxic substances, when immobilized on site or disposed elsewhere.
From a geochemical technology point of view, long-term isolation of pollutants in disposal sites in the dynamic natural environment of the geochemical cycle is impossible and not desirable. Since disposal sites cannot remain completely sealed forever, the controlled leakage of toxic compounds is a preferable solution, needed to slowly defuse a potential environmental bomb. Dilution is a solution to pollution if concentrations in the bio-available phase can remain below safe natural background values.
For truly stable methods of immobilization of most toxic pollutants, such as radioactive compounds now temporarily stored above or possibly definitely in deep clay deposits below ground, nature offers minerals and concretions as examples of alternatives. Take for instance concretions of quartz, composed of the most stable mineral at earth surface conditions and able to encapsulate heavy metals. Not only were they our best friend during the stone age, making for the toughest tools of flint, but further understanding of the way they form, might provide us with efficient geochemical technology to spontaneously attract, concentrate and maintain immobilized, the most dangerous pollutants, even within the dynamic environment at the earth surface and also on the very long-term.