Channahon is a growing community of about 9,000 residents located 40 miles southwest of Chicago. Like many Midwestern groundwater sources, Channahon’s well supply contains radium in excess of the EPA 5 pCi/l maximum concentration standard.
The City needed assistance in designing an economical treatment system capable of removing radium, thereby bringing Channahon’s drinking water into compliance with the new EPA standard. The City worked with Tonka Water in the design phase, drawing on our knowledge and experience in the design and implementation of pre-formed HMO systems for radium removal.
The overall treatment process consists of chemical addition, including pre-formed HMO, pressure detention, and pressure filtration through Tonka Water’s non-accumulative IMAR™ media. The key to the operator friendly pre-formed HMO process for radium removal is uniform mixing and proper feeding of the pre-mixed HMO slurry solution. Channahon utilizes the TonkaBlend™ system to standardize this process, allowing the operator to easily make a consistent concentration of stabilized HMO solution and feed the slurry solution without complication.
The OptaCell Plus™ pressure filter is designed with isolated-cell compartments above and below the arched plate underdrain. This allows for each individual filter cell to be backwashed or taken completely off-line while the remaining filters continue to produce filtered water. The isolated-cell design provides the necessary filter redundancy for the removal of radium; a primary contaminant in a cost-saving, compact footprint.
The treatment process has been highly efficient and exceeds current EPA standards for radium, as well as standards for iron and manganese.
|Iron (Fe)||1.5 mg/L||Not Detected|
|Manganese (Mn)||0.3 mg/L||Not Detected|
|Radium 226||6.6 pCi/L||1.48 pCi/L|
|Radium 228||5.3 pCi/L||0.75 pCi/L|