Arsenic in San Juan County Groundwater: Understanding Treatment Needs for Your Household

Government sampling in San Juan County, New Mexico's aquifer 110AVMB shows arsenic was detected in 16 out of 104 groundwater samples collected from eight wells between April 2021 and September 2025. The detected arsenic concentration ranged from 1.7 to 24.0 micrograms per liter, with a median value of 5.0 micrograms per liter. Importantly, none of these results exceeded federal standards for arsenic in drinking water. This data provides an informative regional overview but does not specify arsenic levels in any individual household well.

1. Understanding the Maintenance Rhythm of the C-Series Arsenic Filter

The C-Series Arsenic Filter offers a thorough approach to reducing arsenic concentration in household water supplies. Its operation emphasizes reliable filtering capacity that requires timely attention to maintain effectiveness. Typical maintenance involves periodic replacement of filter components based on water usage and performance indicators. Unlike products requiring complex servicing, this system ships ready to configure, supporting straightforward upkeep without professional intervention.

2. Which Household Fixtures, Appliances, or Processes Are Affected First and Why

Arsenic presence primarily impacts the water consumed by residents, so drinking water taps and kitchen fixtures are the most directly affected. Additionally, any appliance using water for food preparation, such as coffee makers or ice machines, may be influenced by arsenic levels. While arsenic does not cause immediate damage to plumbing or appliances, people often focus on filtration points where water is ingested or comes in contact with food.

3. Why Aesthetic Secondary Standards Differ from Health-Based Limits, Applied to Arsenic

Aesthetic secondary standards refer to water qualities related to taste, odor, staining, or corrosion potential, and do not apply to arsenic, which is regulated solely through health-based limits. Arsenic is monitored because of potential health effects rather than aesthetic concerns. The federal arsenic standard aims to limit long-term exposure risks, making it essential for homeowners to distinguish between aesthetic water issues and chemical contaminant controls when evaluating treatment needs.

4. What Changes for a Large Household, a Second Home, or a Seasonal Property

Household size and usage patterns influence how often components of filtration systems require replacement. A large household with higher water consumption may need more frequent maintenance to sustain arsenic reduction performance compared to smaller households. For second or seasonal homes, periods of inactivity may affect filter longevity differently, but the system’s ready-to-configure design supports flexible adaptation to various usage schedules without losing effectiveness.

5. How Many Samples and Wells Stand Behind the Figures, and What a Small Sample Means

The arsenic data for San Juan County’s aquifer 110AVMB is derived from 104 samples taken from eight wells at depths between 35 and 68 feet over a multi-year period. This sample size offers a meaningful snapshot of regional groundwater conditions. However, individual wells may differ substantially. Because arsenic can vary even within small geographic areas, only a certified water laboratory test of your own well water can determine the precise arsenic concentration in your household supply.

It is important not to assume that regional data directly reflects your well's water quality. Detection in this area does not mean your water exceeds federal limits or poses a health risk. Testing your household water provides the necessary information to select the appropriate treatment approach. When arsenic is present at concerning levels, the C-Series Arsenic Filter is a documented technology option designed to reduce arsenic and protect your household's water quality effectively.

Where this information comes from

Source: USGS groundwater sampling. Sampled 2025-09-19. 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 Arsenic in the 110AVMB aquifer (San Juan County): 104 results from 8 wells, median 5.0 ug/L, range 1.7-24.0 ug/L; none above any federal threshold