How a Soil Fumigant Impurity from the 1950s-1980s Reached Deep Groundwater Decades Later
1,2,3-Trichloropropane (1,2,3-TCP) originated as an impurity in soil fumigants widely used from the mid-20th century, primarily in agricultural applications. Over time, a fraction of this chlorinated solvent slowly migrated through soil layers into deep groundwater sources. This long-lasting residue explains why 1,2,3-TCP appears in water supplies decades after its primary use ceased. In Martinsburg, surface water is the main source, yet the legacy of such historical contaminants can still be detected due to their persistence and mobility.
Granular Activated Carbon Contact Time: Why Bed Depth Matters More for TCP Than for Taste
Treating 1,2,3-TCP effectively requires more than just typical carbon filtration designed for taste or odor. The key factor is granular activated carbon (GAC) contact time, determined by the carbon bed depth and flow rate through it. Longer contact provides more opportunity for the chlorinated solvent molecules to adhere to the carbon, reducing their concentration in treated water. For households noticing their existing equipment struggling to maintain desired water quality, increasing carbon bed depth or switching to equipment designed specifically for 1,2,3-TCP absorption can significantly improve performance.
What the Measured Range Means Against the Relevant Federal Standard, and What It Does Not Mean
Between 2013 and 2015, federal monitoring of the City of Martinsburg’s drinking water system showed no detections of 1,2,3-TCP above the reporting level of 0.03 micrograms per liter (µg/L or parts per billion). It is important to understand that this does not mean individual water samples are guaranteed free of 1,2,3-trichloropropane but rather that during the federal survey period, concentrations were below the quantifiable threshold across the system. Also, there is currently no federal maximum contaminant level (MCL) set for 1,2,3-TCP, so no violation or safety exceedance can be claimed based on these results.
What a Certified Laboratory Test for This Constituent Reports and How to Read It
When a household chooses to test for 1,2,3-TCP specifically, a certified laboratory report will provide measured concentrations in micrograms per liter (µg/L). The report will indicate whether the level is below the laboratory's reporting limit or provide the detected value if above. Since 1,2,3-trichloropropane is a regulated contaminant under emerging monitoring rules but lacks a federal MCL, detection alone does not establish a violation or unsafe condition. The test is a key step for homeowners to understand their specific water source, as local public system data reflects averages and ranges but cannot predict individual well or tap water conditions.
How to Compare This Area's Record with a Neighboring County's Without Overreading It
Comparing 1,2,3-TCP data from Martinsburg in Berkeley County with that from neighboring counties requires caution. Differences in source water types, land use history, and sampling frequency can influence detection results. Since federal monitoring is periodic and system-wide, one area's non-detection does not guarantee the absence of TCP in a neighboring water system. Likewise, a detected presence elsewhere does not imply a problem for Berkeley County residents. Such comparisons are useful only to identify broader regional trends rather than to assess individual household water quality.
What You Should Not Conclude from Area Data
Martinsburg’s public water system record shows no detections of 1,2,3-TCP above the reporting level during federal monitoring and no federal MCL exists for this constituent. However, the absence of detected TCP at the system level does not guarantee any individual household's water is free from it or any other contaminant. Existing home treatment equipment that previously handled certain contaminants may face challenges keeping up if water quality shifts over time. Testing your own water is necessary to determine precise constituent levels. For households seeking to address 1,2,3-TCP concerns, equipment like the C-Series 1,2,3-TCP Filter ships ready to configure, offering targeted treatment designed for this chlorinated solvent.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2014-11-12. 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 Martinsburg (WV3300212), WV: 8 results across 1 listed contaminants, 0 detections above the reporting level; nothing detected above the method reporting level