Pentek Chromium-6 Filter

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Purpose and Scope of the UCMR3 Survey for Chromium-6

The third Unregulated Contaminant Monitoring Rule (UCMR3) was a nationwide survey conducted by the EPA between 2013 and 2015. Its goal was to collect occurrence data on several contaminants, including chromium-6 (hexavalent chromium), in public water systems to help guide future regulatory decisions. However, the monitoring results represent system-wide measurements, not individual household samples. Therefore, while these data reflect chromium-6 levels in the Powdersville Water District serving Easley, they cannot substitute for a specific test of your tap or well water.

Chromium’s Changing Oxidation States Along the Water Pathway

Chromium exists in various oxidation states, notably trivalent chromium (Cr(III)) and hexavalent chromium (Cr(VI)). Hexavalent chromium is more mobile in water and can convert depending on water chemistry conditions such as pH and oxygen levels during treatment and distribution. Between the surface water source, the distribution mains in Easley, and your household tap, chromium may change oxidation states to an extent that the chromium-6 concentration you experience can differ from EPA survey measurements.

Initial Impact on Fixtures and Appliances

Chromium-6’s presence can first affect appliances and fixtures where water contact is frequent and retention times are long, such as water heaters, filtration units, or ice makers. These points may experience aesthetic issues or gradual material corrosion more noticeably before effects appear in other household water uses like drinking or cooking.

Why Total Chromium Levels Are Not Enough to Assess Chromium-6

EPA data include measurements of both total chromium and chromium-6. Total chromium sums all forms of chromium but does not distinguish the oxidative state, which is critical because hexavalent chromium has different chemical behavior and health considerations than trivalent chromium. For Easley’s water system, only a small portion of total chromium measured corresponds to chromium-6. Assessing hexavalent chromium accurately requires testing specifically for Cr(VI).

Long-Term Effects of Untreated Chromium-6

Exposure to chromium-6 via drinking water over many years can raise concerns due to its chemical properties. While Easley’s public water record shows no health-based violations, prolonged contact may affect the taste or appearance of water and possibly lead to gradual changes in plumbing materials. Addressing chromium-6 presence helps maintain water quality and appliance longevity.

Matching Treatment Capacity to Household Water Use

Choosing appropriate treatment for chromium-6 involves considering your home’s daily water use and the concentration range reported in Easley’s water system. Treatment solutions like the Pentek Chromium-6 Filter ship ready to configure and can be selected based on flow rates and household demand to maintain efficient operation and consistent water quality.

What Area Data Does Not Reveal About Your Water

EPA’s UCMR3 measurements for Easley represent averages and maxima at the public water system level, not individual household water quality. They do not imply water from your specific tap contains the same chromium-6 levels or that chromium-6 is present in your water at all. The presence and concentration of chromium-6 in your household water can only be determined by direct testing. Choosing treatment should be informed by those individual results rather than by regional survey data alone.

Where this information comes from

Source: EPA SDWIS public water system record. Sampled 2015-12-07. These figures describe the public water system's record, not the plumbing inside any individual building.

On record: EPA UCMR3 monitoring (2013-2015) for Powdersville Water District (SC0420002), SC: 48 results across 2 listed contaminants, 25 detections above the reporting level; no federal MCL for hexavalent chromium; total chromium MCL 100 ug/L