By David von Seggern, Sierra Club Maine Volunteer
Lithium, the lightest metal and third element on the atomic chart, has garnered world interest since the start of the electric vehicle industry due to the fact that its properties nicely align with the battery needs of these modern vehicles. For the foreseeable future, lithium-ion batteries will likely have no competition, and thus the demand for lithium will increase greatly as the energy transition plays out.
There are reasons to mine lithium domestically. One is that the US has relatively high standards for mining compared to some of the nations from which lithium is now extracted. Another is that we have become increasingly aware of the strategic value of domestic sources of valuable minerals, especially rare-earth ones. President Biden has made it clear that his administration will be supporting lithium mining in the US — see, for instance, the news that a lithium mining company will get a $700M government loan to develop its lithium prospect in western Nevada.
Mining has traditionally been a small industry in Maine, and has been further constrained by Maine’s 2017 legislation which basically makes it impossible to have large open-pit mining operations. Many people in Western states more friendly to mining are envious of Maine’s strict mining laws. While metallic mining is non-existent in Maine according to a 2015 report of the Maine Geological Survey, Maine’s quarrying industry, which includes stone, gravel, and sand, is robust; and we see many examples with stone in sturdy buildings and in other infrastructure throughout Maine.
It is important to realize that open-pit mining for metallic ores is different from quarrying. Quarrying extracts the target resource usually without creating large amounts of waste rock which must be managed. In an open-pit metallic mine, the ore is extracted from an aggregate which has many unwanted elements and is ultimately disposed of in waste piles or put back into the pit. However, this unwanted material has been crushed to such an extent that undesirable compounds, such as sulfide metals, are now subject to leaching. The leaching process can carry these compounds, or elements of them, into nearby streams, rivers, lakes, and ponds where they become long-term toxic problems. Perhaps the most notorious of these products is mercury sulfide (HgS) which now pollutes Penobscot Bay as well as many other Maine waters.
We have recently heard of a possibly large lithium prospect in the vicinity of Newry, Maine. There, lithium is contained in high concentrations in large spodumene crystals. In order to develop a mine there, some changes are likely needed to current statutes in Maine. These changes will center on whether lithium is in fact a metal (it is, by definition) for mine classification purposes and whether the ore-bearing material (spodumene crystals) can be benignly removed in a quarry-like operation (we doubt it).
Of course the legislature can make a statutory exception to “mineral” for lithium. It will be more difficult to deal with the fact that removal of the large spodumene crystals inevitably requires excavation and crushing of the matrix of rock that surrounds each crystal. Once crushed, whether disposed of on adjacent land or put back into the open pit, the rock matrix must not leach toxic compounds or elements into Maine waters. A comprehensive survey of the geology in the proposed mining area is essential to determine the scope of that threat. This should involve not just sampling surficial deposits but also samples at the deepest depths contemplated for the open pit.
If statutes are changed, the rule-making and the enforcement would ultimately fall on the Maine Department of Environmental Protection. It is, however, important to get the legislation right to begin with. We wish to continue the protections offered by the 2017 legislation without opening new permitting pathways. New permitting pathways might allow levels of pollution which were intended to be prevented in the earlier legislation.