Fleck VOCs & Industrial Chemicals Filter

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How Seasonal Water-Table Changes Move a Solvent Plume Relative to a Well Screen

Seasonal fluctuations in groundwater levels can shift the position of solvent plumes around well intakes.

In Marion County, groundwater supplies the City of Keizer's public water system. Changes in rainfall, recharge, and local hydrology cause water tables to rise or fall throughout the year. These movements influence where volatile organic compounds (VOCs) may accumulate or disperse near well screens. A plume containing VOCs may move closer to or farther from the entry point of water into a household system depending on the season and local groundwater flow patterns.

What a Laboratory's Method Detection Limit Means When a Compound Is 'Not Detected'

'Not detected' indicates concentrations below the lab's ability to reliably measure, not absence.

When testing for volatile organics like 1,1-dichloroethane or chloromethane, laboratories use method detection limits (MDLs), which define the smallest concentration that can be consistently detected. For example, the reporting levels range from 0.03 to 5.0 micrograms per liter (µg/L) or parts per billion (ppb) depending on the compound. A 'non-detect' for a VOC means the compound's concentration in tested water is below that threshold, not necessarily zero.

Which Volatile Organic Compounds Appear in This Record and Which Do Not, Named from the Facts

The City of Keizer's public water system recorded detections of certain VOCs, others were consistently below detection levels.

• HCFC-22 was detected in 4 out of 30 samples above 0.08 µg/L (0.08 ppb), with the highest measured at 0.673 µg/L (0.673 ppb).
• Other monitored VOCs such as 1,1-dichloroethane, chloromethane, bromomethane, Halon 1011, 1,3-butadiene, and MTBE were not detected above their respective reporting levels during monitoring from 2013 to 2015.
• No federal maximum contaminant levels (MCLs) exist for these VOCs under this monitoring rule, and none of the results show any health-based violations.

How to Compare This Area's Record with a Neighbouring County's Without Overreading It

Each county's groundwater VOC data reflect local conditions and sampling scope; direct comparisons require caution.

Government monitoring is designed to detect the presence and approximate levels of volatile organics within public water systems but is not a comprehensive or continuous evaluation of all wells or homes. Differences in geology, industrial activity, and water sources lead to variation between Marion County and adjacent areas. Thus, comparisons should focus on understanding local trends rather than assuming uniformity or risk across regions.

Why Volatility Matters: Showering, Dishwashing and Inhalation Routes Versus Drinking

Volatile organic compounds may enter the household by inhalation or skin contact, not only ingestion.

VOCs, also known as volatile organics or solvent compounds, readily evaporate from water into air during activities like showering or dishwashing. Inhalation of these vapors can be a more significant exposure route than drinking water alone. Understanding these exposure pathways helps homeowners recognize the importance of treating water for VOC reduction beyond taste or odor concerns.

The Household or Facility Symptoms That Do and Do Not Point to This Problem

Symptoms aligned with VOC presence are subtle and require specific testing for confirmation.

• Typical water complaints such as discoloration, staining, or metallic taste do not directly indicate VOC contamination.
• Health symptoms possibly related to VOC exposure require professional assessment and cannot be confirmed by water appearance or smell alone.
• After equipment failure in your household water system, VOC-specific testing is needed to verify current levels rather than assumptions based on area data.

To address VOC concerns at home after existing equipment failure, the Fleck VOCs & Industrial Chemicals Filter ships ready to configure for residential use. This system effectively reduces volatile organics including solvent compounds measured in Marion County's groundwater supply, providing a reliable mitigation step based on documented water quality records.

Where this information comes from

Source: EPA SDWIS public water system record. Sampled 2014-09-24. These figures describe the public water system's record, not the plumbing inside any individual building.

On record: EPA UCMR3 monitoring (2013-2015) for City of Keizer (OR4100744), OR: 210 results across 7 listed contaminants, 4 detections above the reporting level; no federal MCL for these UCMR-listed VOCs