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Yellow boy is the common name for the yellowish-orange precipitate that
results from acid mine drainage. Much like sediment, yellow boy covers the
stream bottom and diminishes fish and aquatic insect habitat. However, unlike
sediment, yellow boy clings to objects it comes into contact with, including
submerged logs, rocks, fish gills, or even aquatic insects. Due to this, yellow
boy is often much more detrimental and displays its effects in a considerably
shorter amount of time. The acidic conditions that lead to yellow boy also
change the water quality making it difficult for the animals that inhabit the
stream.
Iron County was built on the mining of iron ore and the Iron River watershed
has seen many of those ore operations over the course of the 20th
century. Although all of the mines have since closed or moved away, the
evidence of their presence is still noticeable today. While the old mine
buildings and equipment provide historical value for the community, the
waste rock piles and flooded mine shafts still pose some threat to the local environment.
Waste rock piles can be found throughout the watershed, with some of the most
apparent and potentially harmful occurring along the river in a corridor that
extends from Garnett St. in Iron River to Brady Ave in Caspian.
Below: Treatment systems at the Buck and Dober Mine locations allow
for the precipitation and settling of yellow boy before it enters the river,
leading to vast water quality improvements in the Iron River.
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Pyritic iron ore (sulfur-containing iron), in contact with the air and water
oxidizes to create sulfuric acid which reacts with the ore to result in an
acidic iron solution. After further oxidization and the neutralization of the
solutions in water, the iron falls out of solution, forming “yellow-boy”.
Eventually the surfaces of the waste rock piles lose their ability to produce
acid mine runoff. The biggest problem in dealing with eliminating the waste
rock piles is the fact that in disturbing the waste rock, new rock with the
capacity to produce more acid and yellow boy is exposed, aggravating the
situation once again. The nature of the rock along with the vast extent of its
presence in the watershed makes the cost of removal and disposal serious
logistical problems as well.
Above: A typical waste rock pile found along the Iron River.
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| In the past, work has been done at two locations that were known to have a
serious detrimental effect on the river. Both the Dober and Buck mine locations
were addressed by implementing a series of treatment ponds and wetlands which
would allow for the participation and settling of yellow boy before entering the
river. These systems have made a positive impact, yet to date, there has been
no maintenance of the facilities or any study to see if they have reached their
carrying capacity. It is unknown how long these treatment systems will remain
effective, and this coupled with the amount of untreated areas, lend to the high
priority of acid mine drainage. |
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