Project Overview
Introduction
Beginning in 1907, the Consolidated Mine Company opened the Nixon Coal Mine located in Scott Township, Pennsylvania. After the Nixon Mine was closed in 1936, they left behind a disturbed portion of land. This large hole in the ground continuously fills with ground water. This water is contaminated with iron, magnesium, aluminum, sulfur, and other contaminants which are robbing the water of oxygen. With no oxygen in the water, it is unalble to sustain life. This contaminated water finds its way to Scrubgrass Run, killing all life there. Scrubgrass Run flows into Chartiers Creek which eventually empties into the Ohio River, causing a domino effect. In the early part of September 1994 the Chartiers Valley School District along with many other organizations started the Scrubgrass Water Project. An aerobic treatment system has been built on site with hopes of improving the water quality of Scrubgrass Run. Once the system was built it was realized that the system was not working to it's fullest potential. Suggested solutions to this problem include more aeration, filtration and retenetion of contaminated water in the system. Technical assistance with this is needed and appreciated. The Scrubgrass Water Project is a collaborative effort.
Problems
In abandoned mine drainage the groundwater from the mines becomes contaminated with many different metals. In an aerobic passive treatment system the surface water is directed into a pond. The purpose of this pond is to force the chemical reaction between the iron contaminant and oxygen. This process is known as aeration. This chemical reaction between the iron and oxygen produces iron oxide or rust. The second purpose of this pond is to retain the water long enough to allow the rust to settle to the bottom. The water leaves the first pond free of iron, but unfortunately free of oxygen as well. The second pond in the system is used for filtration. This pond filters out other metals such as manganese, magnesium, aluminum, and sulfur. Oxygen is added to the water by using vegetation and natural aeration in the pond. After the water leaves the entire system and enters Scrubgrass Run it is free of metal contaminants and full of oxygen. Therefore the stream is able to support life. There are many limitations in the aerobic passive treatment system at Scrubgrass. The retention time of the first pond does not accommodate the amount of iron oxide produced from the chemical reaction. Instead of the rust settling to the bottom of the first pond it is carried to the second pond. Plus, the iron contaminant level of the water entering the system is so high that not all of it reacts with oxygen, although all of the oxygen is depleted. This allows free iron to enter the second pond. Aeration is still taking place in the second pond, deleting any oxygen that is added by vegetation, and depositing iron oxide. The water that leaves the current passive treatment system brings to Scrubgrass Run iron, iron oxide and no oxygen. Therefore, Scrubgrass still cannot support life.
Solutions
The Scrubgrass Passive Treatment System needs some thoughtful alterations to improve the treatment process. The 1997-98 Enviromental Field Study class has come up with several ideas for improvement. The students are eager to implement the appropriate changes at Scrubgrass, but need professional guidance in order to do so. The solution to the passive treatment system revolve around three main processes: aeration, retention, and filtration. Some suggested solutions to increase aeration are: to construct a waterfall where the water enter the first pond. Or possibly add a series of water-wheels, that churn the water adding oxygen to force aeration where the water enters the first pond. Suggested solutions to increase retention of the water include changing the location where water enters the first pond. The two ideas for achieving this goal are to pipe the water to the far end of the pond or to extend the existing channel. The previous class attempted to increase filtration by planting 2,000 wetland plants in the second pond over the summer. The plants did not survive because the water level exceeded 12 inches. The suggested ideas are to increase the dimensions of the second pond or to somehow regulate the water level. The Students are excited to make some positive changes at the Scrubgrass Treatment site. In order to achieve the goals and make positive changes professional guidance is needed. Though the students have some basic ideas for the changes, these ideas need to be expanded and improved. The class needs and would appreciate the advice and help of professionals possessing experience with treatment systems to analyze the ideas and determine if they will accomplish the necessary goals.
Home - Project Overview - Time Line - Progress Report - Data - Projects - Period 4-5
Period 7-8 - Related Sites - Message Board - E-mail Us!