Well 27 Radium Study

Well 27

December 16, 2016

Madison Water Utility is moving forward with a unique radium study, and Edward Klief Park is set to play a pivotal role. The study will bring together utility staff and experts from the Wisconsin Geological and Natural History Survey in an effort to pinpoint possible sources of radium found in the water at Well 27 on North Randall Ave. (pictured above), which is located about 900 feet from Klief Park.
In early spring, MWU plans to work with the Survey to drill a small, 6-inch diameter test well at the park, which should take about seven to ten days to complete. The well would be a similar depth to municipal Well 27, but its bore hole would be about 26 inches smaller in diameter, allowing for easier, less costly geological analysis. Radium has always occurred naturally in underground rock formations below Madison. Assuming that conditions at the park are similar to conditions at nearby Well 27, the test well should help utility staff determine which rock layers below ground are contributing radium to Well 27’s water. Madison Water Utility will then move the study to Well 27 and attempt to seal those layers if possible.
  Klief Park
(Photo: Utility officials hope to drill the 6-inch diameter well near existing plantings by the low wall) 

Some parts of the study are already underway. MWU is analyzing the original rock pulled from Well 27 when it was drilled in 1989. Core samples have been tested with a technique called XRD, or X-ray defraction, to determine their composition. Results of that analysis are currently being compiled at UW Madison. A similar analysis will be performed on small rock cuttings pulled every five feet during drilling of the test well in Klief Park. Once the test well is drilled, the Survey and MWU staff will spend several weeks logging the bore hole and pulling water samples from various depths.
While radium testing results at Well 27 do not violate any federal health standards, Madison Water Utility takes the issue very seriously. The utility stepped up monitoring of the well in 2015 after test results showed higher-than-expected radium levels (see complete monitoring data in the chart below). The federal Maximum Contaminant Level (MCL) for radium is a consistent result of 5 picocuries per liter (pCi/L) or higher during an entire year of quarterly testing. The MCL is meant to ensure the safety of water over a lifetime of consumption. MWU officials hope that the 2017 study and mitigation efforts will bring an overall reduction in radium levels at the well. Well 27 is generally used during only the high-demand summer months and is currently offline for the winter.

Testing Date     Combined Radium (pCi/L)
2/23/2015     5.7  
4/8/2015     4.0  
5/19/2015     6.2  
7/21/2015     3.3  
8/12/2015     4.3  
9/29/2015     6.4*  
10/27/2015     5.6  
11/10/2015     4.3  
12/8/2015     4.6  
12/8/2015     4.4  
12/9/2015     3.6  
12/10/2015     5.6  
12/11/2015     3.0  
12/11/2015     3.4  
12/11/2015     3.4  
12/15/2015     2.7  
12/15/2015     2.27  
12/16/2015     4.3  
12/16/2015     3.8  
12/16/2015     1.46  
12/17/2015     3.8  
12/17/2015     4.4  
2/16/2016     5.2  
2/16/2016     4.2  
5/31/2016     3.1  
6/1/2016     3.3  
8/17/2016     2.94  
9/29/2016     4.9  

 *There was a problem with the analysis of this sample.