When considering volatile organic compounds (VOCs) in your Cassatt household water, it’s important to recognize what local public water system data can—and cannot—tell you. The EPA’s data from the Cassatt Water Kershaw-Lee Co. Regional Water Authority (serving over 25,000 people) provides a snapshot of VOC levels in the groundwater source. However, this information reflects system-wide monitoring and does not directly establish the concentration in your specific home’s tap water.
How a Gasoline Release Differs from a Dry-Cleaning Release in What It Leaves in Groundwater
Gasoline and dry-cleaning solvents are common sources of VOC contamination, yet they differ in chemical makeup and persistence. Gasoline-related VOCs typically include compounds like 1,1-dichloroethane and MTBE (methyl tertiary-butyl ether), both measured in Cassatt’s water system but not detected above reporting limits. Dry-cleaning solvents often include chlorinated compounds such as tetrachloroethylene, which were not among detected contaminants in the local monitoring.
These differences matter because the detection and behavior of VOCs in groundwater depend on the chemical type and how it interacts with soil and water flow. Groundwater affected by gasoline releases may contain different VOC fingerprints than water influenced by dry-cleaning chemical releases.
Why Volatility Matters: Showering, Dishwashing, and Inhalation Routes Versus Drinking
Volatile organic compounds can enter the body through ingestion and also through inhalation and skin contact during activities like showering and dishwashing. Their volatility means they can vaporize from water into air, increasing inhalation exposure.
For example, chloromethane and halon 1011 were measured in the Cassatt system at low levels, indicating some presence of volatile organics. However, the absence of any EPA health-based violation for VOCs in this water system signifies that the measured levels are within ranges federally considered not to pose health risks based on current knowledge. Nonetheless, household exposure could vary depending on individual water use and the specific water source.
How Seasonal Water-Table Changes Move a Solvent Plume Relative to a Well Screen
Seasonal fluctuations in groundwater levels can shift solvent plumes vertically and horizontally around a well’s intake (well screen). This movement affects VOC concentrations sampled in system monitoring, contributing to variation over time.
In Cassatt’s case, monitoring from 2013 to 2015 shows occasional detection of chloromethane and halon 1011, but no consistent trend of increasing VOC levels. Such variability is expected given changes in groundwater flow and solvent plume positions relative to well screens through seasons and years.
How Seasonal or Multi-Year Variation Shows in the Record (Dates and Ranges Given)
The Cassatt Water system's data covers results collected between 2013 and 2015. During this period, chloromethane was detected twice at levels up to 0.75 micrograms per liter (µg/L or parts per billion), and halon 1011 was detected twice, with a peak at 0.86 µg/L. Other VOCs like 1,1-dichloroethane, bromomethane, HCFC-22, 1,3-butadiene, and MTBE were consistently not detected above reporting limits.
This temporal data indicates that the presence of volatile organics in the groundwater source can fluctuate, but the EPA record for Cassatt reports no health-based violations related to VOCs during this monitoring.
What Distinguishes This Problem from the Two Problems Most Often Confused With It
VOCs differ distinctly from other common water quality concerns such as microbial contamination and heavy metals. Microbial contaminants affect water’s biological safety, while heavy metals like lead or arsenic impact toxicity differently, requiring distinct testing and treatment solutions.
VOCs are organic solvents that tend to affect taste, odor, and potential health through chronic exposure at certain levels, unlike sediment or mineral-related issues that change water hardness or clarity.
What a Laboratory's Method Detection Limit Means When a Compound Is 'Not Detected'
When a lab reports a VOC as 'not detected,' it means the compound’s concentration is below the method detection limit—the smallest amount the test can reliably measure. For Cassatt, these limits range from 0.03 to 5.0 µg/L depending on the compound.
Thus, a 'not detected' result does not guarantee the absolute absence of a VOC but indicates if present, it is below the laboratory’s detection capability. To know your home's precise water quality, testing of your specific water sample at an accredited lab is necessary.
Addressing VOCs in Your Water
If you want to reduce the presence of VOCs and industrial chemicals in your household water, specialized systems like the C-Series VOCs & Industrial Chemicals Filter are designed to target these compounds effectively. The C-Series System ships ready to configure for your home’s water treatment needs and provides a documented approach to mitigating volatile organics based on your own water testing results.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2015-02-02. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA UCMR3 monitoring (2013-2015) for Cassatt Water Kershaw-Lee Co. RWA (SC2820005), SC: 89 results across 7 listed contaminants, 4 detections above the reporting level; no federal MCL for these UCMR-listed VOCs