Common belief: Any detected 1,4-Dioxane in public water means immediate safety concerns for residents
In the Bear and Hockessin areas of New Castle County, Delaware, the Artesian Water Company supplies surface water to over 230,000 people. Government monitoring through EPA's Unregulated Contaminant Monitoring Rule (2013-2015) recorded 1,4-dioxane detections in some samples, with levels ranging from just above the reporting threshold of 0.07 micrograms per liter to a maximum of 2.2 micrograms per liter. While the EPA has set a cancer risk reference concentration at 0.35 micrograms per liter for 1,4-dioxane, there is currently no federal maximum contaminant level (MCL). This means detections do not represent violations or unsafe conditions but rather indicate the presence of this chemical at varying concentrations in the public supply.
Common belief: Plumbing materials and the age of household pipes do not affect 1,4-Dioxane presence
The monitoring data pertains to water as it flows into the distribution system, primarily sourced from surface water. Household plumbing materials and the age of piping do not contribute to 1,4-dioxane levels; the chemical originates in the source water itself. However, plumbing can impact other water qualities, but for 1,4-dioxane, the presence depends on what enters from the public system, not on internal household fixtures or pipe composition.
Common belief: The water system’s source type or sample depth does not influence 1,4-Dioxane levels detected
The Artesian Water Company's supply is surface water, which typically can have different contaminant profiles compared to groundwater sources. Depth of sampling or individual well depths are not applicable for this publicly supplied system. The data collected reflects surface water treatment outcomes across the distribution system rather than variances caused by groundwater wells or depths. For households on private wells, the situation would differ, requiring separate testing not represented by these system-wide results.
Common belief: Households and commercial users must evaluate 1,4-Dioxane risks in the same way
Commercial and industrial users often face additional considerations such as volume needs, regulatory reporting, and specific process water requirements. Households, however, focus on daily consumption and exposure through common fixtures. The EPA monitoring dataset specifically represents overall public system conditions; for households experiencing failed equipment designed to address 1,4-dioxane, assessing the system water quality carefully is essential. Commercial evaluations generally require more comprehensive analysis beyond these community-wide measurements.
Common belief: 1,4-Dioxane levels remain constant year-round in public water systems
The Artesian Water Company’s data was collected between July 2013 and July 2014, showing a range of detected concentrations. Detection frequency and concentrations can vary due to seasonal changes, treatment adjustments, and environmental factors affecting surface water quality. These fluctuations are typical and do not reflect an immediate change in safety or compliance status. Understanding this variability helps households interpret testing results in context rather than assuming a fixed contamination level.
For households in Bear and Hockessin with existing water treatment equipment that has failed, the best next step is to arrange a comprehensive water test specifically for 1,4-dioxane at the point of use. This test will provide accurate, site-specific results critical for deciding appropriate water treatment solutions. The C-Series 1,4-Dioxane Filter system ships ready to configure and is designed to address 1,4-dioxane presence documented in municipal water systems like Artesian’s, offering a targeted mitigation option for residential settings.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2014-07-16. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA UCMR3 monitoring (2013-2015) for Artesian Water Company (DE0000552), DE: 36 results across 1 listed contaminants, 11 detections above the reporting level; no federal MCL; EPA cancer risk reference concentration 0.35 ug/L