Pentair 1,2,3-TCP Filter

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Why 1,2,3-Trichloropropane Resists Air Stripping and What That Means for Treatment Choice

Many people initially assume that volatile organic compounds like 1,2,3-trichloropropane (often called TCP or 1,2,3-TCP) can be easily removed from water through air stripping. This is a misunderstanding. TCP is a chlorinated solvent with a low volatility relative to other organics, meaning it does not readily escape from water into air. Standard air stripping equipment, which relies on this evaporation process, is generally ineffective for reducing TCP concentrations. For residential users in Roanoke City, this means that typical equipment designed for volatile compounds may not address concerns related to 1,2,3-TCP, and alternative technologies should be considered.

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

Water use patterns heavily influence the choice of treatment equipment for 1,2,3-TCP. Larger households consume more water daily, increasing the demands on any water treatment technology. In contrast, second homes or seasonal properties have intermittent use, which can affect equipment performance and maintenance cycles. Systems configured for continuous, high-volume use need components sized to handle peak demand without compromising effectiveness. Conversely, equipment scaled for occasional use might have different operational considerations but still must ensure consistent reduction of chlorinated solvents like TCP when the water is in use.

What Questions a Commercial or Industrial Operator Adds That a Household Does Not

While residential water consumers focus on consistent, safe water for daily activities, commercial and industrial operators often add concerns such as regulatory compliance, large-scale water volume handling, and integration with existing treatment infrastructure. These users may require detailed monitoring and verification of TCP concentrations and adherence to health-based standards specific to their operational context. Residents, by contrast, are best served by proven direct-purchase technologies that ship ready to configure for household scale, addressing 1,2,3-trichloropropane without additional complexity.

Why the Reporting Level for This Solvent Is Thousands of Times Lower Than for Common Metals

The federal occurrence survey for the Western Virginia Water Authority, which serves Roanoke City, sets a reporting level for 1,2,3-TCP at 0.03 micrograms per liter (µg/L), equivalent to 0.03 parts per billion (ppb). This threshold is considerably lower than levels typically set for metals. The reason is the potential toxicity and persistence of TCP even at trace amounts. Although detections below the reporting level are not violations or necessarily harmful, the low threshold reflects conservative monitoring standards to keep public water safe and well-informed.

How a Soil Fumigant Impurity From the 1950s–1980s Reached Deep Groundwater Decades Later

1,2,3-Trichloropropane was historically used as an impurity in soil fumigants between the 1950s and 1980s. Over time, this chlorinated solvent migrated through soil layers, eventually reaching deep groundwater sources in some regions. For surface water systems like the Western Virginia Water Authority's that serve Roanoke City, the risk of 1,2,3-TCP presence comes from watershed contamination and runoff, rather than direct groundwater infiltration. Understanding this history helps clarify why even modern water supplies test for TCP and highlights the persistence of certain chemicals in the environment.

Government sampling conducted from 2014 to 2015 under the EPA’s third Unregulated Contaminant Monitoring Rule (UCMR3) found no results above the 0.03 µg/L reporting level for 1,2,3-trichloropropane in the Western Virginia Water Authority system serving Roanoke City. This record documents system-wide occurrence data and is not a test of any individual residence's water supply. To know your home's actual 1,2,3-TCP content, a specific water test from your source is necessary.

For households considering treatment options, the Pentair 1,2,3-TCP Filter is an available technology that ships ready to configure for home use. This technology targets chlorinated solvents including 1,2,3-trichloropropane, addressing concerns that standard air stripping cannot. Before selecting any equipment, testing your water can confirm the presence and concentration of TCP, enabling a well-informed choice tailored to your household’s water needs.

For detailed water quality information from the Western Virginia Water Authority, refer to the EPA’s public water system records and UCMR3 monitoring data available online.

Where this information comes from

Source: EPA SDWIS public water system record. Sampled 2015-12-17. These figures describe the public water system's record, not the plumbing inside any individual building.

On record: EPA UCMR3 monitoring (2013-2015) for Western Virginia Water Authority (VA2770900), VA: 41 results across 1 listed contaminants, 0 detections above the reporting level; nothing detected above the method reporting level