Healthy Streams at Risk of Detrimental Pollutants from Abandoned Mine Drainage

Healthy Streams at Risk of Detrimental Pollutants from Abandoned Mine Drainage

Tyler Drainville

ABSTRACT

Pennsylvania is peppered with abandoned coal mines from its previous steel history. With many of the mines occupying space near local streams and tributaries, mining runoff is getting closer to polluting high quality streams. Some stream systems have already been affected and local bioengineers have put in systems to diminish the pollution. As time goes on, more acidic and toxic mining runoff is accumulating. Much of this toxic water is just waiting for the right conditions to leak into a nearby stream. This would cause serious issues within the collective riparian zone and could affect main rivers such as the Monongahela, Allegheny, and Ohio. Americans need to focus on the root of the stream pollution problem: abandoned mine drainage.

INTRODUCTION

        Pittsburgh, Pennsylvania is known as America’s Steel City. From the mid to late 1800’s, local industries were beginning to produce iron and steel for America’s backbone. However, in doing so, steel pioneers set up what could ultimately be local freshwater’s downfall. Today, abandoned mines are depositing their hazardous pollutants into nearby streams. Not many streams have been affected by any major catastrophes, like that in Las Animas River in Colorado, but nothing is being done to stop an occurrence from happening. This review will be covering riparian zones, abandoned mine drainage, species influences and reactions to acidic pollutants, and which natural factors can either help or worsen the future condition of stream health.

Little Sewickley Creek and Wingfield Pines

Local mines have been abandoned for decades. For coal runoff to surmount, a significant amount of time needs to take place. Just before Chartier’s Creek, north of Pittsburgh, there are large volumes of strip mine runoff. This contaminant causes large amounts of ferrous iron to be deposited into Wingfield Pines which can then be turned into sulfuric acid if given a few more years for the reactions to take place1.  Areas such as these have already been affected and remediation plans needed to fix it can cost a significant amount of money, physical effort, and have environmental drawbacks1.

        Little Sewickley Creek is a local stream that has exceptional water quality compared to the rest of the state is. This second order stream has been given the highest water quality rating in Pennsylvania2. Under the Pennsylvania Code’s description, the waters are on a protected stream on the “statewide list [and are] high quality waters and [allow] trout stocking”2. There is a reasonably large list of criteria that this stream needs to be checked for before it can be deemed as a high quality stream. Much of the criteria refers to the dissolved oxygen present, pH stability, biological sustainability, and ionic/metal components2. The downfall to this system of lower order streams is found just outside the Little Sewickley Watershed. There are three abandoned coal mines localized near the watershed that have not been closely analyzed since the early 90’s. Little Sewickley Creek has Brook Trout being reintroduced, ample acid neutralizing components, and high quality riparian habitats. The value of this stream is worth preserving since it offers such a strong biological presence for functional and structural integrity. Overlooking Little Sewickley Creek could lead to severe costs. Without preservation of native streams, abandoned mine drainage could lead to the deterioration of the local watersheds and ruining the surrounding wildlife.

Local Riparian Habitats

        Little Sewickley Creek houses a diverse habitat comparatively to other Pennsylvania watersheds. This second order stream is home to aquatic life ranging from beavers, to native trout, to various macroinvertebrates. It is important to note that riparian zones are crucial to the health of the surrounding land and especially downstream of the zone4,5. A riparian zone is a biome that includes the crossroads where land and stream meet. This can be a small habitat, or one that encompasses many miles4,5.

        It is necessary to preserve this habitat because with its loss, the human communities located around and downstream of Little Sewickley Creek would be subject to a quickly declining ecosystem. At Wingfield Pines, much of the wildlife is a direct resultant of the pollutants that fill the filter ponds. The water is a muddy orange, a non-diverse wetland marsh is produced downstream, and animal presence is minimal because of the contaminated waters13. Though the problem of abandoned mine drainage is passively remediated far downstream, it is difficult to support a diverse habitat with such restricting circumstances3. The pH of the contaminated ponds are low to where, if heavily introduced and monitored, only few native species of fish could handle the acidity3. Trout are common in the area and are signs of a healthy stream because they are relatively delicate freshwater fish. As it is, currently at Little Sewickley Creek the streams are put under decent levels of stress because of natural runoff6. Without the presence of limestone, which alkalizes streams, natural acid runoff from nearby streets and drainage systems would render the high quality stream too high in acidity to sustain native aquatic life3.

Abandoned Mine Drainage

        Oxidation of sulfide and iron containing compounds are a primary cause of acid build up in Pennsylvania mines7. Oxidation is a natural process that would happen in a natural environment over time. However, the increased exposure from mining has sped up the oxidation process. Extraction processes that are utilized in the mining industry result in increased chemical reactions7. Exposing large quantities of sulfide minerals to an increased surface area to reagents such as H2O and air cause rapid oxidation7. When this oxidation occurs, sulfur and iron components in the rock can erode and dissolve in rain water. Ions formed from these reactions form acidic compounds. The most common being sulfuric acid and ferric (III) oxide. Note that ferric (III) oxide by itself is not an acid, but it can be oxidized in solution to produce acids7. Ferric (III) oxide can cause a distinct, visual change in the water when precipitate is formed. Affected water turns yellowish orange and is called “Yellow Boy”. What many might not understand are the ramifications that can be brought upon the ecosystem if there happened to be acidic drainage into local streams.