Source: http://blog.al.com, February 7, 2012
By: Connie Baggett
Almost a year after routine monitoring showed increased levels of arsenic and vinyl chloride in groundwater test wells at Baldwin County’s Magnolia Landfill, officials are set to approve a $33,765 investigation to find the sources.
County and state officials dismissed elevated arsenic and vinyl chloride testing in September 2010, saying elevated levels detected then were erroneous. But then, the chemicals showed up again in testing in March last year. That prompted county officials to come up with a plan to find the source of the contamination.
According to county documents, geologists with Highland Technical Services will conduct and “alternate source demonstration” to find out if the arsenic that periodically appears in groundwater tests at the site is naturally occurring. Geologists will do nine soil borings up to 30 feet deep and take up to four soil samples from each. A laboratory analysis of the soil should show if the arsenic is from naturally occurring minerals in the soil.
Commissioners are scheduled to vote on the final plan at today’s meeting.
In the vinyl chloride testing, geologists will conduct surveys of the area in an effort to find potential sources of the contaminant.
County staff members said the contaminants could be from sources other than the lined cells at the landfill, including the property’s former use for agriculture or as a military base.
Vinyl chloride is used in production of plastics like polyvinyl chloride pipes, and was once used as a propellant in aerosol sprays. It is a known carcinogen and has been linked to liver damage in people exposed to the chemical.
Arsenic is used in industry to strengthen metal alloys and is commonly found in car batteries and has been used as a pesticide in agriculture. In high concentrations, it can be lethal. In lower concentrations, it can cause skin irritations and an increased risk of lung cancer.
Geologist Billy Cooch told commissioners in December that the contaminants are no cause for concern.
Testing in March found arsenic and vinyl chloride. Retests in September found no arsenic but vinyl chloride levels still present. Arsenic can occur naturally in areas with iron oxide. Vinyl chloride is not a naturally occurring substance, Cooch said, but is used industrially as a solvent.
Baldwin County Solid Waste Director Jim Ransom in December said that the .4 parts per million level of arsenic could be from naturally occurring chemicals in the soil, but the vinyl chloride level, which doubled from .2 to .4 parts per million, likely came from recycling operations at the site.
The arsenic level is within allowable limits, he said, but the vinyl chloride was beyond limits for that chemical. Ransom said the recycling activities have been moved to the lined disposal cell area of the landfill as a precaution.