Some effects of century old abandoned lead mining operations on streams in Missouri,USA

Lead has been mined in the Old Lead Belt region of southeastern Missouri, USA since the early 1700s. Mining operations ceased totally in 1972. Since no other major industries were associated with the region, an investigation was initiated to study the long-term environmental effects of lead mining activities on the water quality sediments and biota otarea receiving streams. The principal study area was Flat River Creek,. which drained the major mining operations of the region. The findings of this study indicated the water of the lower Flat River Creek below the mining elevation contained elevated levels of lead, zinc, calcium and magnesium. The sediments and biota of the same stream area were also found to contain significantly higher levels of lead and zinc as well as copper and cadmium. Algae, crayfish and minnows were all found to have concentrated these metals. The studies indicated that some type of abandonment plan must be developed for the control and treatment of heavy metal pollution for mining operations on a continuing basis.     

Lead, Zinc, Copper, and Cadmium in Fish and Sediments from the Big River and Flat River Creek of Missouri's Old Lead Belt

The Old Lead Belt of Missouri was a major lead-producing region for over a century. Several large tailings piles and other industrial wastes remain behind, though mining operations in the region ceased in 1972. Samples of stream sediments and fish were collected from established sites on the Big River and Flat River Creek over a 3-year period from 1998 to 2000 to evaluate ongoing remediation efforts and determine the current impact of residual mining wastes. Benthic sediments and fish taken in the vicinity of inactive industrial sites were found to contain elevated concentrations of Pb, Zn, Cu, and Cd. Concentrations of Pb and Zn in fillets of suckers and sunfish, as well as in whole bodies of sunfish, correlate well with metal concentrations observed in surficial sediments. The results of analyses provide valuable quantitative information regarding specific sources, current levels of contamination, potential risk to public health, and will allow more accurate assessment of continuing remediation efforts.     

Fish from Missouri's lead belt: To eat or not to eat

Data collected over the past four years indicate that filets of suckers and some species of sunfish taken from certain sites in Missouri's Old Lead Belt consistently contain elevated lead concentrations which exceed the limit of 0.3 g/g suggested by the World Health Organization. The problem exists in bottom-feeding species taken from some sites along the Big River affected by erosion from abandoned lead tailings piles. Fish from many other sites within the Old Lead Belt and the New Lead Belt, including current wastewater treatment systems, are within the acceptable limits for lead in food. Public health implications are discussed relative to observed lead concentrations and available data regarding lead toxicity to humans.     

AQUATIC ORGANISMS AND HEAVY METALS IN MISSOURI'S NEW LEAD BELT1

The New Lead. Belt of southeastern Missouri has recently become the largest lead producing region of the world. The impact of this rapid development on the previously rural and undeveloped region of the Missouri Ozarks is the subject of a continuing interdisciplinary study. Since the industrial development began, there have been a number of nuisance biological blooms in several of the small streams receiving effluent from the mines and mills. The major constituents of the problem algal growths were identified and found to include: Cladophora, Oscillatoria, Mougeotia, Zygnema, Spirogyra, Cymbella, and a variety of other stalked and non-stalked diatoms. Secondary blooms of Sphaerotilus were observed to reach problem proportions in some streams, particularly in the autumn. Finely ground rock flour and mineral particles escaping from tailings dams were found to be trapped by the stream vegetation. Concentrations of lead, zinc, copper, and manganese in the algal and bacterial mats were found to be inversely related to distance downstream from the tailings dams. Consumer organisms, including crayfish, snails, aquatic insects, tadpoles, minnows and larger sunfish were analyzed to determine the extent of dissemination and concentration of the heavy metals through food chains. Preliminary results indicated insignificant concentrations of heavy metals in those consumer organisms studied, though in at least one problem stream the normal consumer organisms mentioned were markedly reduced in numbers.     

Geochemistry,mining and the environment

This paper reviews literature on the sources of lead-zinc mining pollution, and specifically deals with the water and air pollution aspects of these operations. Problems associated with mining and the environment are also discussed. The problems are geochemical in nature but also economic, social, political and legal. Individuals doing research in these boundary conditions are poorly publicised and rarely recognised outside of their own narrow industry.The paper notes that it is possible to have both an economical mining operation and a clean environment. The New Lead Belt region of Southern Missouri, the world's largest lead-mining region lies underneath a national forest with a pure, pristine, undisturbed ecosystem having high recreational value to the nearby cities. By early cooperation between governmental scientists, mining industry, environmental scientists and engineers of the University of Missouri and other universities it was possible to develop this deposit and at the same time keep the pristine nature of the surrounding forest without spending a single day in court or litigation. Problems did arise, but problem-solving sessions dealt with them, not lawyers.