Water Source and Delivery in Yarmouth, Barnstable County
The Yarmouth Water Department serves about 38,900 people across 16,360 connections using groundwater as its primary source. Water is drawn from local aquifers and treated before distribution to residential taps. This system is monitored for various chemicals, including volatile organic compounds (VOCs), using federal occurrence surveys conducted from 2013 through 2015.
Understanding "Not Detected" in Laboratory Testing
Method Detection Limit Explained
When a laboratory reports a compound as "not detected," it means the chemical was below the method detection limit specific to the test. For example, for chloromethane in Yarmouth's system, no results were above 0.2 micrograms per liter (µg/L), the reporting threshold. This does not guarantee absolute absence but indicates the concentration, if present, is very low.
Implications for Household Water
Not detected means the compound level was below the test's sensitivity. Actual household levels require independent testing of that specific tap water to be confirmed.
VOC Occurrence in Yarmouth's Public Water System
VOC Compounds Detected and Not Detected
- 1,1-dichloroethane: Detected in 3 of 26 samples above 0.03 µg/L; highest measured 0.12 µg/L
- HCFC-22: Detected in 1 of 26 samples above 0.08 µg/L; highest measured 0.11 µg/L
- Chloromethane, bromomethane, halon 1011, 1,3-butadiene, MTBE: Not detected above their respective reporting levels
Understanding Detected, Median, and Range
Detected values are points where presence was confirmed above reporting limits but not considered violations or unsafe. Median values represent the middle concentration among detected values, showing typical levels within detections. Ranges provide minimum to maximum detected values, illustrating variability.
How a C-Series VOCs & Industrial Chemicals Filter Addresses VOCs
VOC Removal Mechanism
This solution uses specialized filtration technology to reduce volatile organics like 1,1-dichloroethane and HCFC-22 from the water supply after it reaches the home. Granular activated carbon within the system adsorbs these compounds, effectively lowering their concentration at the tap.
Benefits for Residential Use
By targeting solvent compounds and other VOCs common in the area’s water supply, this filter helps households improve water taste and reduce chemical exposure concerns. It ships ready to configure for residential plumbing systems.
Role of Plumbing Materials and System Age
Separating Source Water from Household Plumbing
VOC data reflects groundwater quality delivered to the municipal system, not changes or additions from home plumbing. Older piping can influence water quality through leaching or interaction with water chemistry, but VOC presence mainly originates from the source water.
Consider Testing Plumbing Influence Separately
To differentiate VOCs from supply water and household plumbing, testing samples from both the system entry point and various household faucets is advisable.
Closing: The Single Test to Clarify Your Household VOC Status
Ordering a certified laboratory VOC analysis of your tap water is the definitive way to understand your household's VOC concentration. This test will provide exact microgram per liter (or parts per billion) figures for volatile organic compounds, if present, and settle any questions informed by area data.
Where this information comes from
Source: EPA SDWIS public water system record. Sampled 2015-09-17. These figures describe the public water system's record, not the plumbing inside any individual building.
On record: EPA UCMR3 monitoring (2013-2015) for Yarmouth Water Department (MA4351000), MA: 190 results across 7 listed contaminants, 4 detections above the reporting level; no federal MCL for these UCMR-listed VOCs