How did a soil fumigant impurity from the 1950s-1980s reach deep groundwater decades later?
1,2,3-trichloropropane, often shortened as 1,2,3-TCP or TCP, is a chlorinated solvent once used as an impurity in soil fumigants prevalent from the mid-20th century. Though its use declined, residues from that time period can persist in the environment. Over decades, TCP can migrate from soils down into groundwater or surface water sources, especially in areas with historical agricultural activities.
In the case of Wailuku, Maui County, the primary water supply is surface water serving over 74,000 people through more than 20,000 connections. This water source can be influenced by past land use and the natural movement of substances through soil and water.
Granular activated carbon contact time: why bed depth matters more for TCP than for taste
To address compounds like 1,2,3-trichloropropane, treatment options often involve granular activated carbon (GAC). The effectiveness of GAC depends heavily on contact time—the duration water spends interacting with the carbon media. For TCP, this is more critical than for contaminants affecting taste because TCP molecules require sufficient exposure to adsorption sites within the carbon bed for meaningful capture.
Increasing bed depth of GAC filters improves contact time, enhancing the ability to capture chlorinated solvents like TCP. This principle guides design choices in water treatment equipment geared toward managing TCP presence.
What do 'detected', 'median' and 'range' mean in the sampling record on this page?
The EPA’s Unregulated Contaminant Monitoring Rule (UCMR3) data, collected from 2013 to 2015 for the Wailuku public water system, show that none of 43 samples had detections above the reporting level of 0.03 micrograms per liter (µg/L), which equals 0.03 parts per billion (ppb), for 1,2,3-TCP. A 'detected' reading means the instrument found a measurable amount above this threshold, but the data here show no such detections.
The 'median' would indicate the midpoint value if detections were present, and 'range' would describe the lowest to highest measurements recorded. Since no detections above the reporting level occurred, these statistical terms are not shown but are critical in interpreting other datasets.
What does a certified laboratory test for this constituent report and how should it be read?
If you want to determine 1,2,3-trichloropropane levels in your household water, a certified laboratory analysis is necessary. Such testing measures TCP concentration in micrograms per liter (µg/L) or parts per billion (ppb), providing a precise figure for your water specifically.
It is important to understand that EPA data for Wailuku relate to system-wide sampling and do not reveal individual home water concentrations. Testing your own water is the only way to know the TCP level at your tap. A laboratory report will typically list detected contaminants, their concentration, and the reporting limits, helping you assess if treatment is warranted.
What is the maintenance rhythm of the documented technology in plain terms?
The Pentair 1,2,3-TCP Filter ships ready to configure and is designed for residential use to address concerns about TCP in water. The key to its ongoing effectiveness is regular media replacement or regeneration based on usage volume and water quality. This maintenance schedule ensures the granular activated carbon bed retains the capacity to adsorb chlorinated solvents adequately.
Unlike more complex systems, this solution does not require specialized service personnel but depends on following specified maintenance intervals to sustain performance in reducing 1,2,3-trichloropropane.
For households in Wailuku measuring or estimating TCP levels in their water, the Pentair 1,2,3-TCP Filter offers a direct purchase option. It provides a practical approach to managing potential chlorinated solvent presence by applying proven adsorption principles tailored to typical residential needs.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2015-02-20. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA UCMR3 monitoring (2013-2015) for Wailuku (HI0000212), HI: 43 results across 1 listed contaminants, 0 detections above the reporting level; nothing detected above the method reporting level
- ✓ 90-Day Money-BackNo restocking fees — return within 90 days.
- ✓ Manufacturer WarrantyGenuine Fleck · Pentair · VIQUA equipment.
- ✓ Free Expert SizingTalk to a specialist and buy the right system the first time.