Autotrol 1,2,3-TCP Filter

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How California's 5 ng/L State Limit Compares With the Absence of a Federal MCL

Residents in Marion County relying on the City of Keizer's groundwater supply may note that 1,2,3-trichloropropane (commonly called 1,2,3-TCP or chlorinated solvent TCP) is a subject of growing concern elsewhere, especially in California where a strict state limit of 5 nanograms per liter (ng/L or µg/L) applies for this chemical. However, the federal government has not established a maximum contaminant level (MCL) for TCP. This means the U.S. EPA offers no enforceable drinking water standard for 1,2,3-TCP as of now. While California’s threshold serves as a benchmark, it is not legally binding for public water systems in Marion County under federal rules or the EPA’s Safe Drinking Water Information System (SDWIS) records.

Granular Activated Carbon Contact Time: Why Bed Depth Matters More for TCP Than for Taste

When household water-treatment equipment fails, concerns grow about contaminants like 1,2,3-TCP that are challenging to address. Effective mitigation often involves granular activated carbon (GAC), which traps chlorinated solvents through adsorption. Unlike taste or odor issues, 1,2,3-TCP removal depends heavily on sufficient contact time between water and the carbon bed—meaning deeper or larger beds typically enhance performance. This characteristic makes upgrading or replacing smaller or shallow filter beds critical for treating TCP effectively. Depth and flow rate matter because insufficient contact allows TCP to pass through untreated.

The Agricultural Land-Use History of the Region and How It Maps Onto Detections

Marion County’s history includes extensive agricultural activity, which is relevant to understanding the presence of chlorinated solvents like 1,2,3-TCP. TCP has been used in soil fumigants and other agricultural chemicals. While no detections above the EPA’s reporting level were found during federal monitoring in the City of Keizer's public groundwater system, agricultural land use can influence localized groundwater contamination over time. However, the 30 samples taken from 2013 to 2015 by EPA UCMR3 monitoring showed no detected TCP above the reporting level of 0.03 micrograms per liter (30 parts per trillion). This suggests no widespread or significant TCP presence in the municipal source water during that period.

A Worked Example: Reading the Record’s Median and Range as a Homeowner Would

The EPA public water system record for the City of Keizer reports 30 monitoring results for 1,2,3-TCP, all below the detection limit of 0.03 µg/L. For a homeowner, this means the median concentration is effectively zero, and no samples indicated the presence of measurable TCP at or above that threshold. While this data does not reveal the exact concentration at any single homeowner’s tap, it provides a regional context indicating that TCP has not been found at detectable levels during the federal unregulated contaminant survey. Homeowners concerned about their own water quality must obtain specific testing at their tap to know their individual TCP concentration.

How Many Samples and Wells Stand Behind the Figures, and What a Small Sample Means

The 30 samples referenced reflect periodic monitoring across the City of Keizer’s groundwater wells used to serve 38,585 people through over 10,700 connections. While this sampling provides useful regional insight, it represents a limited number of wells and points in time. Consequently, the absence of detected TCP does not guarantee zero TCP in all homes. Fluctuations in groundwater chemistry and well locations mean that individual water sources could differ. Testing your own water with an appropriate laboratory remains the only way to confirm 1,2,3-TCP levels at a specific household.

If existing water treatment equipment has failed, a system titled the Autotrol 1,2,3-TCP Filter ships ready to configure and is designed specifically to address concerns about 1,2,3-trichloropropane using granular activated carbon technology optimized for chlorinated solvents. It offers a documented option for households seeking to reduce 1,2,3-TCP when verified present.

To summarize, EPA monitoring data for Marion County’s City of Keizer groundwater system, which supplies tens of thousands of residents, found no detectable 1,2,3-TCP over multiple samples during 2013-2015. This record, available through the EPA’s Safe Drinking Water Information System, covers the public water system and not individual household plumbing or wells. For those with failed treatment equipment concerned about TCP, individual water testing is essential alongside considering technology designed for chlorinated solvent adsorption.

Where this information comes from

Source: EPA SDWIS public water system record. Sampled 2014-09-24. 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 Keizer (OR4100744), OR: 30 results across 1 listed contaminants, 0 detections above the reporting level; nothing detected above the method reporting level