Belief: 1,2,3-TCP Levels in Local Water Are Regulated by a Federal Maximum Contaminant Level
Many think 1,2,3-trichloropropane (TCP) in water is limited by a federal Maximum Contaminant Level (MCL). In reality, there is currently no federal MCL for 1,2,3-TCP. The Environmental Protection Agency (EPA) included 1,2,3-TCP in a nationwide unregulated contaminant monitoring rule (UCMR3) to gather occurrence data, not for regulatory compliance. The City of Laramie’s water system, serving over 32,000 people in Albany County, shows no detectable 1,2,3-TCP above the reporting level of 0.03 micrograms per liter (µg/L), equivalent to 0.03 parts per billion (ppb), based on 2013 sampling. This means no federal standard violation or health-based violation is recorded for this constituent in the municipal supply.
Belief: Activated Carbon Filters Work the Same for Removing 1,2,3-TCP As They Do for Taste and Odor Compounds
It is commonly assumed that any granular activated carbon (GAC) filter effective for taste or odor issues in water will also adequately address 1,2,3-trichloropropane. However, TCP is a chlorinated solvent that requires deeper carbon bed contact time than typical taste or odor contaminants. Filter bed depth and flow rate critically influence how well TCP can be reduced in a treatment stage. Effective equipment designed specifically for this compound, such as the C-Series 1,2,3-TCP Filter, uses optimized carbon bed depth and system configuration tailored for this challenge.
Belief: A Home Water Test Reporting 1,2,3-TCP Will Always Use the Same Reporting Limits As Government Surveys
Laboratory testing for 1,2,3-TCP can vary in detection limits depending on the method and lab accreditation. The EPA’s UCMR3 monitoring used a reporting level of 0.03 µg/L. A certified laboratory test commissioned individually for your residence may have different detection limits or quantitation thresholds. Reading a test result requires understanding whether the detected concentration is above or below the method’s minimum reporting level. If a test shows “non-detect” or “below reporting level,” it means the compound was not measurable at or above that threshold, but it does not guarantee absolute absence.
Belief: 1,2,3-TCP Is the Same Concern as General Chlorinated Solvent or Industrial Chemical Contamination
While 1,2,3-trichloropropane belongs to the family of chlorinated solvents, it differs from common industrial chemicals or more prevalent solvents found in some water sources. 1,2,3-TCP typically originates from historical use as a soil fumigant or as an impurity in certain pesticides. Its occurrence in water is distinct and less widespread than many organic contaminants. This specificity influences monitoring priorities and treatment approaches. Understanding this difference is essential before assuming a treatment or concern overlaps with other chlorinated contaminants.
Belief: When Testing for 1,2,3-TCP, Skip Other Checks and Go Straight to a Specialized Laboratory Test
Before requesting a specialized analysis for 1,2,3-TCP, it’s practical to rule out simpler factors first. Begin with reviewing public water system records and compliance data, which for Laramie show no 1,2,3-TCP detection above reporting limits. Next, check municipal consumer confidence reports and review any known nearby industrial or agricultural sources. If private well water is the source, collect a water sample from a state-certified laboratory with expertise in volatile organic compound (VOC) testing to obtain an authoritative measure of 1,2,3-TCP. This stepwise approach helps avoid unnecessary testing and contextualizes any result.
What Albany County Data Should Not Lead You to Conclude
The absence of detected 1,2,3-TCP above the reporting level in City of Laramie’s surface water-based public supply, as recorded by EPA monitoring from 2013–2015, does not guarantee that any individual household’s water is free of this compound. The data represent system-wide monitoring, not individual tap water tests. Conversely, it also does not imply any inherent health risk from the municipal water system, because no health-based violations are on record. To know your household water’s condition, only a direct, certified laboratory test of your own sample provides definitive information.
When action is desired based on test results or precautionary measures, treatment equipment designed to address 1,2,3-trichloropropane like the C-Series 1,2,3-TCP Filter ships ready to configure for residential use. This product uses technology proven to reduce TCP effectively, particularly in systems where elevated levels are confirmed. It is one option to consider after confirming your water’s unique quality through testing.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2013-11-19. 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 Laramie (WY5600029), WY: 10 results across 1 listed contaminants, 0 detections above the reporting level; nothing detected above the method reporting level