Article courtesy by Jim Bloch | December 31st 2012 | Voice News | Shared as educational material
Water plants in the Drinking Water Monitoring System, established in 2006, used between one and four devices to test the water for chemical contamination.
St. Clair was the only municipality to have all four; it no longer participates in the monitoring network. None of the current local participants have more than two devices.
None operates the Cadillac of detection devices, the gas chromatograph/mass spectrometer, or GC-MS, which is able to detect individual pollutants.
A number of water plants have bailed out of the network, citing money woes, in addition to St. Clair, including Port Huron, East China and New Baltimore. The result is that area residents are more at the mercy of chemical spills than at any time in the last half-decade.
The four devices are a multi-parameter probe, a total organic carbon analyzer, a fluorometer and the gas chromatograph/mass spectrometer.
The GC-MS is the monitoring tool of choice because it can detect specific, dangerous chemicals – ones that persist in the environment, tend to be carcinogenic and tend to bio-accumulate in the food chain. The GC-MS in St. Clair tested for 27 specific volatile organic compounds, including benzene, carbon tetrachloride, hexane, MTBE, styrene, toluene and vinyl chloride. A GC-MS is not cheap, running about $150,000 and costing about $30,000 per year to operate and maintain, according to Annette DeMaria, an engineer with Environmental Consulting & Technologies, who helped set up and maintain the equipment.
The multi-parameter probe measures seven water quality parameters: pH, a measure of how acidic the water is; conductivity, a measure of the water’s ability to conduct electricity; turbidity or the clarity of the water; dissolved oxygen, where excess organic material can cause oxygen deficiencies; chlorophyll, where higher levels suggest higher algal growth; oxidation reduction potential, a measure of the water’s capacity to oxidize contaminants; water temperature; and, at Monroe, blue-green algae. The probe reports at 15-minute intervals. It costs about $7,000 new and about $2,600 per year to operate and maintain.
“The multi-parameter probe lets you know if something is in the water,” said Bari Wrubel, chairperson of the new, smaller incarnation of the monitoring system, called the Huron to Erie Drinking Water Monitoring Network. He supervises the water and wastewater plants in Marysville.
But it doesn’t tell you exactly what it is.
Specific lab tests have to be performed to find the specific contaminant. Samples must be bench tested in the plant or, more likely, transported to Lansing for testing, a process that can take hours, if not days. “If no one in the system is using a gas chromatograph/mass spectrometer, you don’t know what’s causing the anomalous readings,” observed a person attending the Lake St. Clair Conference in Harrison Township, Nov. 29-30, where Wrubel and DeMaria discussed the re-formed drinking water monitoring network.
“That’s true,” said DeMaria. But water plants do not necessarily need to know exactly what’s coming downriver to shut off their intakes. “It’s a lot better than not having any detection at all,” said Wrubel.
Ideally, Wrubel would like to find a way to set up the GC-MS device somewhere between Marysville and Algonac and use it to test so-called “grab samples” taken of the raw river water at plants, even if the network can’t afford to use it full-time. “The fluorometer checks for petroleum based spills,” said Wrubel. It costs about $25,000 new, and runs about $10,000 a year to operate and maintain, said DeMaria.
“Water plants use Total Organic Carbon (TOC) measurements to determine the cleanliness of the source water,” said DeMaria via e-mail. “High total organic carbon indicates high levels of decaying natural organic matter or high levels of manmade materials such as detergents, pesticides, fertilizers, herbicides and industrial chemicals. Beyond indicating the presence of manmade chemicals, water with high TOC from natural sources can produce harmful byproducts once the water passes through the water treatment process.”
“Too much and it reacts with the free chlorine you’re using to disinfect the water in the plant, creating cancer-causing chemicals,” said Wrubel. A TOC analyzer runs about $35,000 new and costs about $10,000 per year to operate and maintain. At his plant, Wrubel runs the multi-parameter probe and this summer added a fluorometer, which Marysville bought from St. Clair after it had dropped out of the network.
When the network was set up in 2006, a federal grant purchased the equipment and pair for its maintenance. ECT later showed plant operators how to maintain their own equipment, but many chose to have ECT do it, a cost that added to their financial burden when the grant money dried up. “We’re calibrating the equipment on our own, which saves a lot of money,” said Wrubel – perhaps $5,000-6,000 per year.
Marine City and Ira Township run the multi-parameter probe only, as will Algonac when it comes back on line. Mount Clemens is equipped with the multi-parameter probe and a total organic carbon analyzer. Both Detroit plants and Monroe run multi-parameter probes, TOC analyzers and fluorometers, as will Wyandotte when it’s back on line. Monroe added an eighth probe to its multi-parameter device that tests for blue-green algae, toxic blooms of which have plagued the western basin of Lake Erie for the past few years. All members can view online the reports emanating from all member water plants.
Jim Bloch is a freelance writer. Contact him at firstname.lastname@example.org.