1. By Chris Ford and James Hughes (4078845) (4092011)

2. History Rocky Mountain Arsenal (RMA) was established in 1942, during World War 2. The US Army manufactured chemical weapons until the 1960’s and destroyed weaponry through the 1980’s. Post WW2, the areas was leased for use in the manufacture of pesticides, insecticides and herbicides until 1982. Presently the area is of high environmental importance and is a wildlife refuge.

3. How did the Arsenal become contaminated? The manufacturing wastes that were generated from the Arsenal, were disposed using practices accepted and well known at the time. The contamination occurred from two factors: The disposal of wastes Accidental sewage leaks, spills and wind dispersion

4. Contaminant details The extent of the contamination lies largely in 5 factions: Ground-water, Soil, Lakes, Surface-water and Plants. Wind dispersion also spread the contaminants over a wide area and leaching occurred. Contaminants include semi-volatile chemicals, heavy metals and volatile organic compounds. Levels of contamination were established through 9700 samples of soils. Another 3900 other samples were and are continuing to be taken.

5. The Cleanup In 1989, the U.S. Army and Shell Oil Company entered into the RMA Federal Facility Agreement with the U.S. Environmental Protection Agency. As part of the FFA, the Army and Shell implemented remedial actions with all applicable regulations, laws and agreements. The total cost for the cleanup program is estimated to cost $2.4 billion.

6. Groundwater treatment The groundwater treatment consists of 3 systems. 5 groundwater pumping stations Containment Barrier Injection of a Hydrogen Release Compound (HRC) £180 million for the baseline groundwater treatment Contaminants: Organic compounds, Arsenic etc

7. Soil remediation The main remediation method is of contaminated soil removal. This contaminated material is then transported and stored in a Double-Lined Landfill, ensuring environmental protection for ‘1000’ years. Lesser contaminated materials are instead placed into several monitored basins; their capping layers used to promote runoff. 3.8 million cubic metres of soil have been removed.

9. Summary RMA will become one of the largest urban national wildlife refuges once remediation is complete. The RMA has been recognized as being among the safest workplaces of its kind with recognition from the Occupational Safety and Health Administration in April ‘09. The Army and its contractors have excavated more than 3.8 million cubic metres of contaminated soil. In addition, the 5 groundwater pumping stations have treated 3.5 million metres cubed of contaminated groundwater each year. In 2007, the EPA awarded the site with its national Land Revitalization Award.