Manganese in Union County Water: Understanding Local Range and Treatment Options

Union County, Arkansas, draws groundwater primarily from aquifer 124SPRT. Water from this deep aquifer—sampled between 260 and 771 feet below ground—reaches homes through private wells. Understanding manganese levels in this regional source helps households facing challenges with existing water treatment equipment.

If You Want to Know What the Local Manganese Range Means Compared to Federal Standards

Government sampling by the U.S. Geological Survey tested 14 groundwater samples from 11 wells throughout Union County’s aquifer 124SPRT between 2012 and 2019. Manganese was detected in all samples, with values ranging from 1.49 to 29.2 micrograms per liter (ug/L) and a median of 8.61 ug/L. Importantly, none of these results exceeded the federal secondary maximum contaminant level, which addresses aesthetic concerns rather than health risks.

This data does not indicate manganese concentrations in any single household well. Detection alone is not a violation or a safety concern. It simply shows manganese is present in measurable amounts in regional groundwater samples.

If You Wonder How Manganese Enters Groundwater in This Area

Manganese naturally occurs in soils and rocks in the Union County region. Over time, manganese minerals dissolve from geological formations and enter the aquifer that supplies water to residential wells. It does not come from human-made pollution sources here but reflects local geology interacting with groundwater.

If You Consider How Well Depth and Source Type Affect Expected Levels

The 11 sampled wells ranged in depth from 260 to 771 feet, showing manganese is present throughout the aquifer’s vertical profile. Deeper wells can sometimes have different concentrations due to variations in rock types and chemical conditions, but this sampling shows manganese detection is consistent across typical residential well depths in this region.

If You Need to Understand Why Secondary Standards Differ from Health-Based Limits

The federal secondary standard for manganese is established to prevent water discoloration, staining, and unpleasant taste or odor. It is not a health-based limit. Detection of manganese below or near this level generally does not pose a health risk but may cause water quality issues that can affect laundry, plumbing fixtures, or appearance.

If You Are Curious About Seasonal or Multi-Year Variation in Manganese Levels

The sampling spanned over seven years, from mid-2012 to late 2019, during which manganese was detected consistently without large swings outside the reported range. This stability suggests that manganese concentrations in Union County groundwater typically remain within these bounds over time. However, individual well conditions and usage patterns can cause variation, so periodic testing is advisable.

What Water Test Should You Order Next?

To determine manganese levels specific to your home water, order a comprehensive test from a certified laboratory that includes manganese concentration measurement. This single test will clarify whether manganese is present at a level affecting your water quality or equipment.

If manganese presence is confirmed and is linked to failed water treatment equipment, consider the C-Series Black Manganese Stains Filter. This system ships ready to configure and is designed specifically to address manganese-related water issues in residential settings.

Where this information comes from

Source: USGS groundwater sampling. Sampled 2019-09-18. These figures describe groundwater sampled in this area. They are not a test of any individual private well - only a test of that well can establish its own water.

On record: U.S. Geological Survey sampling of Manganese in the 124SPRT aquifer (Union County): 14 results from 11 wells, median 8.61 ug/L, range 1.49-29.2 ug/L; none above any federal threshold