What does a laboratory test report for 1,2,3-trichloropropane typically show?
A lab report measuring 1,2,3-trichloropropane (sometimes called TCP or the chlorinated solvent) in drinking water presents detected concentrations in micrograms per liter (µg/L) or parts per billion (ppb). These figures indicate the presence of the compound but do not alone determine if the water is unsafe or violates any regulations. For Montgomery County’s main public water system, monitoring from 2013 to 2015 recorded 1,2,3-TCP in some samples, with detected levels ranging up to 0.169 µg/L. There is no federal maximum contaminant level (MCL) for 1,2,3-TCP, so these detections do not represent violations or health-based exceedances.
How did 1,2,3-TCP, an impurity from soil fumigants used decades ago, reach deep groundwater today?
1,2,3-trichloropropane was historically an unintended component found in soil fumigants applied widely from the 1950s to the 1980s. Over time, this compound has migrated downward through soil layers, eventually reaching groundwater aquifers. Despite restrictions on its use, TCP’s chemical stability allows it to persist in the environment, meaning that residues from past agricultural applications can still be found in water sources now.
What does Montgomery County’s agricultural history tell us about the presence of 1,2,3-TCP?
Montgomery County has a varied land-use history, including areas that were farmland during the mid-20th century when soil fumigants containing TCP impurities were common. These agricultural practices correlate spatially with some detections of 1,2,3-TCP in water samples collected from the public water supply. While not all areas show this compound, locations linked to former farmland are more likely to have trace levels due to legacy contamination.
How does California’s 5 nanograms per liter limit for 1,2,3-TCP compare to the absence of a federal MCL?
California enforces a stringent 1,2,3-TCP guideline set at 5 nanograms per liter (ng/L), or 0.005 µg/L, reflecting a precautionary approach to this contaminant. By contrast, the federal Environmental Protection Agency has not established a maximum contaminant level for 1,2,3-trichloropropane, so there is no nationwide legal limit. Montgomery County’s public water system reported detected levels up to 0.169 µg/L, which is above California’s threshold but not a federal violation, illustrating differences in regulatory approaches.
How can a homeowner interpret the median and range of 1,2,3-TCP detected in Montgomery County’s water record?
Reviewing the public water system’s monitoring data, four detections of 1,2,3-trichloropropane were above the reporting level, with a median concentration of 0.0905 µg/L. This means that half of the detected results were below and half above this median value. However, these numbers represent system-wide sampling rather than individual household levels. A homeowner should understand these figures as a regional indicator rather than a personal water safety measure.
What does the number of samples and wells behind these figures mean for interpreting 1,2,3-TCP data?
The Montgomery County water record includes 52 samples evaluated between January and October 2013. The relatively limited number of detections suggests that 1,2,3-TCP presence is not widespread at high levels, but it also means there is some uncertainty about variations within specific neighborhoods or private wells. A small sample size limits how precisely one can infer household water quality from the system’s data alone.
How should Montgomery County’s 1,2,3-trichloropropane data be compared with a neighboring county’s results?
Comparing public water records between counties should be done cautiously. Different water sources, usage patterns, and land histories affect concentrations. For example, a neighboring county might have fewer or more detections depending on its agricultural legacy and water management practices. Interpreting differences requires understanding these contextual factors to avoid overgeneralizing or misapplying the data to your own household.
What is the recommended test to determine your household’s 1,2,3-TCP level?
To know the precise concentration of 1,2,3-TCP in your home’s water, a specific laboratory analysis of your tap water is necessary. Only such a test can settle questions about your residence’s water quality and help decide if any treatment would be beneficial. For managing detected 1,2,3-trichloropropane, equipment like the C-Series 1,2,3-TCP Filter ships ready to configure and is designed to address this contaminant effectively at the point of use.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2013-10-31. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA UCMR3 monitoring (2013-2015) for Aqua PA - Main System (PA1460073), PA: 52 results across 1 listed contaminants, 4 detections above the reporting level; no federal MCL