1. What the UCMR3 Nationwide Survey Sought to Reveal and Its Household-Level Limits
The unregulated contaminant monitoring rule (UCMR3) collects data on substances like chromium-6 (hexavalent chromium, Cr(VI)) in public water systems to help federal agencies understand nationwide occurrence. The results here reflect sampling at the Big Sandy Water District level, which supplies about 13,000 people in Boyd County through surface water sources. The 2013–2015 data set does not provide household-specific results and cannot define chromium-6 levels at any individual tap.
2. Changes in Chromium’s Oxidation States and Their Journey to Household Water
Chromium(III) and chromium(VI) forms may transform between source, distribution mains, and the tap due to chemical and biological reactions. Hexavalent chromium (Cr(VI)) is distinct from total chromium measurements and can exist differently depending on water chemistry and treatment steps. Its presence in public water arises mainly from natural or industrial sources, fluctuating within parts per billion (µg/L) levels.
3. Understanding 'Detected,' 'Median,' and 'Range' in This Sampling Record
Of 32 chromium-6 tests on Big Sandy Water District water, 22 showed detection above a reporting level of 0.03 µg/L (or parts per billion), with measured values ranging from just above 0.03 µg/L up to 0.099 µg/L. The median of detected results was approximately 0.045 µg/L. Similarly, total chromium was detected in 16 out of 32 samples, ranging from 0.2 to 0.33 µg/L, with a median near 0.26 µg/L. These figures reflect measurement, not a violation or health risk, as no federal maximum contaminant level exists specifically for chromium-6, and the total chromium MCL is 100 µg/L.
4. The Sample Size Behind the Figures and What a Small Number Implies
The data derives from testing 32 samples collected across the system's distribution network but represents only a snapshot of the water quality over time. While providing useful regional context, this limited sample set means individual household water can differ due to local plumbing, treatment, or source variations. Testing of your own water remains essential to determine exact chromium-6 levels for your residence.
5. Seasonal and Multi-Year Variation Reflected in Sampling Dates and Ranges
Sampling took place between August 2013 and May 2015, a period covering multiple years and seasons. Chromium-6 concentrations may vary due to source water changes, treatment adjustments, and environmental factors across this timeframe. This variability underscores the importance of understanding that these figures are temporal snapshots rather than constant measurements.
Closing: Addressing Your Chromium-6 Treatment Needs
To meet your household’s specific chromium-6 treatment demand, especially when considering the Boyd County Big Sandy Water District profile, the Fleck Chromium-6 Filter ships ready to configure as a technology designed to manage Cr(VI) in residential water. Selection should follow a test of your home water supply to determine the necessary capacity and performance requirements.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2015-05-29. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA UCMR3 monitoring (2013-2015) for Big Sandy Water District (KY0100944), KY: 64 results across 2 listed contaminants, 38 detections above the reporting level; no federal MCL for hexavalent chromium; total chromium MCL 100 ug/L