Summary #
Aluminum is a metal commonly found in AMD that can be toxic to aquatic life at elevated concentrations. This page explains how aluminum enters waterways, its behavior at different pH levels, and how it is measured.
Some information compiled using “Impacts of Mine Drainage on Aquatic Life, Water Uses, and Man-made Structures” http://www.dep.state.pa.us/dep/deputate/minres/districts/CMDP/chap04.htm l
Aluminum is one of the most abundant elements in the earth’s crust and occurs in many rocks and ores, but never as a pure metal. Aluminum combines with organic and inorganic ions and can be found in several forms. Aluminum can change form but it cannot be destroyed. Under natural, pristine conditions, aluminum rarely occurs in water at concentrations greater than a few tenths of a milligram per liter.
Waters with high concentrations of aluminum, often seen flowing bright white, are toxic to aquatic life due to lowered pH levels. Increased aluminum concentrations can be related to abandoned mine discharges, acid precipitation and the natural breakdown of clays. When aluminum precipitates (drops) out it coats channel rocks, eventually destroying the streams ecosystem. Aluminum precipitate can be directly toxic to fish and macroinvertebrates. Aluminum affects fish by accumulating on their
gills thereby affecting their breathing. At a combined pH of less than 5.5 and a dissolved aluminum concentration greater than 0.5 mg/L, almost all fish and macros will be eliminated. Of the three major metals found in AMD, aluminum has the most severe effect on aquatic life.
Aluminum samples are taken using standard procedures and analyzed in a lab. Results are recorded in mg/L and the State Drinking Water Limit is.2 mg/L.
Sources/Links (as provided in the source text):
- http://www.dep.state.pa.us/dep/deputate/minres/districts/CMDP/chap04.htm
Related Pages #
- Developing a Monitoring Plan — Structuring your monitoring program
- Removing Metals (Chemistry Concepts)
- Ferrous and Ferric Iron (Chemistry Fundamentals)
Source and Last Reviewed #
Source: AMR Clearinghouse (amrclearinghouse.org). Migrated to AML-Connect. Last Reviewed: 2026-03-13.
[Admin note: Some external links in this article may be outdated. Verify before relying on them. Flag dead links for removal or replacement.]
Tags: metals, monitoring, sampling, amd
