Government records from the EPA's Safe Drinking Water Information System show that the Columbus public water system, serving Franklin County residents, has undergone federal monitoring for a range of volatile organic compounds (VOCs) between 2013 and 2015.
Detection Limits and 'Not Detected' Results
Laboratory Method Detection Limit Explained
When a VOC such as 1,1-dichloroethane or chloromethane is reported as 'not detected,' it means the concentration was below the laboratory's method detection limit. For example, any 1,1-dichloroethane concentration below 0.03 micrograms per liter (µg/L or ppb) would not register in these tests. This does not confirm the compound is absent—only that if present, it is at very low levels.
Seasonal Water Table Changes and Solvent Plume Behavior
Movement of VOCs in the Aquifer
Seasonal fluctuations of groundwater tables can shift solvent plumes, which consist of VOCs, relative to water supply wells. These changes may influence concentrations detected in samples taken from a water system but do not directly translate to an individual household's water quality at every moment.
Interpreting 'Detected,' 'Median,' and 'Range' in VOC Sampling
Understanding Regional VOC Measurements
- Detected: A compound measured above the laboratory’s detection threshold in one or more samples, indicating presence within the system's supply area but not a violation.
- Median: The middle value in the range of detected concentrations, representing typical levels in the system's source water during monitoring periods.
- Range: The span from the minimum to maximum detected levels across samples, showing variability but not implying safety concerns when below health-based limits.
Differences Between Public Water System Monitoring and Private Well Testing
Scope and Purpose of Monitoring Data
EPA data on public water systems covers large populations, reflecting overall water quality rather than any single home’s levels. To determine VOC concentrations specific to a household’s water, an independent laboratory test of the home’s supply is necessary. Public system data help identify regional patterns but cannot substitute for personalized testing.
Granular Activated Carbon Bed Sizing: Beyond Flow Rate
Importance of Contact Time for VOC Removal
Filtration equipment for VOCs, including the Autotrol VOCs & Industrial Chemicals Filter, relies on granular activated carbon technology. Effectiveness depends on contact time—the duration water remains in contact with the carbon bed—not just the flow rate. Proper sizing ensures sufficient adsorption of volatile organic compounds and industrial chemicals from residential water.
This page reviewed regional VOC data for Franklin County from the Columbus public water system, clarifying what detection limits, seasonal water movements, and sample statistics mean for households. It outlined why private water testing is necessary to confirm individual VOC levels and described how an advanced carbon filter system addresses these compounds effectively.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2014-12-16. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA UCMR3 monitoring (2013-2015) for Columbus (OH2504412), OH: 72 results across 7 listed contaminants, 0 detections above the reporting level; nothing detected above the method reporting level