What a Laboratory Test Report for 1,2,3-TCP Actually Lists
Reported concentration as micrograms per liter (µg/L) or parts per billion (ppb)
Lab reports show the measured level of 1,2,3-trichloropropane (TCP) expressed in micrograms per liter, which is the same as parts per billion. Detection means an instrument measured the chlorinated solvent, but it is not a safety finding. To know your home's water level of TCP, a specific sample test of your tap or well is necessary.
Granular Activated Carbon Contact Time: Why Bed Depth Matters More for TCP Than for Taste
Longer contact time increases TCP interaction with the carbon bed
TCP is a chlorinated solvent requiring sufficient contact time with granular activated carbon (GAC) for effective treatment. The depth of the carbon bed directly impacts how long the water interacts with the carbon, which is more critical for TCP than for taste-related substances.
Compact beds may reduce treatment efficiency for TCP
Shallower carbon beds can treat aesthetic issues, but might not provide enough contact time to address TCP effectively. Households seeking to reduce TCP levels should consider equipment that allows for deeper or more extensive carbon contact.
How California's 5 ng/L State Limit Compares With the Absence of a Federal MCL
California sets a public health goal of 0.005 µg/L (5 nanograms per liter)
This state limit reflects a precautionary threshold for TCP, far lower than typical regulatory levels for many compounds. In contrast, federal standards do not include a maximum contaminant level for 1,2,3-TCP, indicating no formal legal limit currently applies at the national level.
Federal absence of a limit means detections are not violations
The Environmental Protection Agency’s (EPA) Unregulated Contaminant Monitoring Rule (UCMR3) data for North Shelby Water District showed no TCP detected above 0.03 µg/L, a reporting threshold. Since no federal maximum contaminant level exists, these findings are monitoring results, not exceedances.
How Public-System Records Differ From Private-Well Testing in What They Establish
Public system monitoring represents the entire supply, not an individual home
The North Shelby Water District serves over 14,000 people and operates with surface water sources. Its records show no detections of TCP above the reporting limit during federal sampling. While reassuring for the system overall, individual homes may have different circumstances requiring their own tests.
Private wells require separate testing for current TCP levels
Public water system data do not replace a private well test. A household on a private well or with unique plumbing should obtain a specific laboratory analysis to understand any 1,2,3-TCP presence.
What Changes for a Large Household, a Second Home, or a Seasonal Property
Treatment capacity must match water use patterns
A larger household or one with fluctuating occupancy, such as a seasonal residence, should consider equipment with sufficient capacity to handle daily water demand. Treatment devices designed for 1,2,3-trichloropropane need to maintain proper performance over varying flow rates and water volumes.
Extended periods of inactivity can affect filter performance
Homes used seasonally should plan for maintenance and flushing to ensure effective chlorinated solvent treatment when in use, as stagnation may influence water quality at the tap.
Why Aesthetic Secondary Standards Differ From Health-Based Limits, Applied to This Constituent
Secondary standards address taste, odor, and appearance, not health safety
Regulatory thresholds concerning chloride or total dissolved solids relate to water's sensory qualities. These differ from health-based considerations of chlorinated solvents like TCP, which involve different testing and treatment criteria.
TCP is evaluated using health-based monitoring, not aesthetic standards
While some water constituents impact corrosivity or staining, 1,2,3-TCP concerns center on potential health effects assessed separately from aesthetic parameters.
How to Judge Treatment Capacity Against the Household’s or Facility’s Daily Demand
Match filter performance to peak water usage
Evaluating treatment equipment for 1,2,3-trichloropropane involves ensuring the capacity meets or exceeds the household’s maximum daily consumption. This alignment supports consistent exposure levels within targeted limits.
Consider regeneration or media replacement based on demand
Equipment relying on granular activated carbon may require periodic media renewal or regeneration. Households should assess their water usage patterns to anticipate maintenance frequency and maintain effective TCP contact time.
Summary and Government Source
The North Shelby Water District’s federal sampling record shows no detection of 1,2,3-TCP above 0.03 µg/L in public water between 2013 and 2015. This data applies to the system overall and should be supplemented by private testing for individual households as needed. For detailed EPA monitoring data, refer to the UCMR3 public water system records.
Households weighing treatment options for TCP, including the Fleck 1,2,3-TCP Filter, should consider water demand, carbon bed depth, and specific testing results to make informed decisions on water quality management.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2015-10-12. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA UCMR3 monitoring (2013-2015) for North Shelby Water District (KY1060324), KY: 16 results across 1 listed contaminants, 0 detections above the reporting level; nothing detected above the method reporting level