In that letter, recommended action #3 was to (emphasis added):
"Intensify sampling of well water by increasing the frequency of sampling and adding contaminants for analysis to include all known or suspected contaminants present on the surface or in the surficial aquifer (groundwater just below the surface)."Why was increased water well monitoring by LUS recommended? Consider these facts that undergird the rationale for improving LUS's water well monitoring and highlight the urgency :
- Lafayette's abandoned railyard, a site of known contamination, is a little more than 1000 feet from a number of our LUS drinking water wells.
- Additional sources of potential contamination (such as the site of a 1926 manufactured gas plant) exist near our water wells.
- Near surface contamination at the abandoned railyard has likely spread laterally off-site over the past century.
- Contamination known to exist in the railyard has been monitored in the upper Chicot Aquifer under the railyard.
- LUS has detected surface contaminants in some of our drinking water wells.
You might have assumed that our LUS well water is already being frequently tested for all contaminants that reasonably might get into our drinking water. You would be wrong in that assumption! Currently, LUS monitors and reports only a generic list of contaminants at a frequency of once every three years in each of our municipal drinking water wells.
To estimate just what fraction of known organic contaminants from nearby contaminated sites are monitored and reported by LUS, I searched through the supporting exhibits filed in court by the complainants in their lawsuit against the Union Pacific railroad.
From the lawsuit exhibits, I compiled a list of all named organic contaminants that were detected and documented in samples from the railyard site (Tables 1-2). That list of railyard contaminants is based on only a few samples and is quite unlikely to include all of the organic contaminants that will eventually be discovered at the railyard site. However, the list does give us a basis to estimate what fraction of railyard contaminants are monitored from our drinking water wells. If you have an interest in seeing a separate list of specific chemical names, you can view the list of contaminants by clicking here.
Results - In the railyard lawsuit exhibits, a total of 49 organic contaminants were reported as being detected. Of these, only 15 (31%) are currently monitored and reported by LUS (Figure 1, and Tables 1-2).
|Figure 1. Only 15 of the 49 organic contaminants detected at the abandoned railyard are monitored and reported water from the LUS drinking water wells.
So, returning to the question in the title: "What percent of known railyard contaminants are monitored by LUS in our well water?" The answer: About 31%, less than one third of known contaminants are monitored in our drinking water wells and publicly reported by LUS!
Furthermore, even for the 15 monitored contaminants, each well is sampled at the astonishingly low frequency once every three years. This fact led to the other requested action in the citizens' letter - to increase frequency of sampling. Implementing increased monitoring frequency is particularly important for the LUS water wells which already have had a detection of a surface contaminant. As with the other citizen recommendations, there is no indication that LUS and our city's "leaders" have ever considered this recommended action.
And, one last word - Note that in Lafayette LUS has reported detection of contamination that must have originated from near the ground surface, but, to the author's knowledge LUS has never detected any organic contaminants in untreated Lafayette well water that exceeds EPA maximum contaminant limits for protection of human health (MCLs). The concern being raised here and in the recommendation letter is that the observation of any surface contaminants in our well water is evidence of contaminant breakthrough. That is, we are seeing the beginning of surface contamination reaching our water supply.
The increased monitoring requested in recommendation #3 is just one of the actions needed to better safeguard our citizens and ratepayers. LUS management under the guidance of our local political leadership have the constitutional duty to safeguard public health, and to ensure protection of LUS ratepayers by ensuring that the parties responsible for the contamination pay all costs of additional monitoring, remediation, and any/all added costs of treatment.
Table 1. This table lists the 15 contaminants known to be present at the abandoned railyard and monitored/reported by LUS in untreated well water samples taken once every 3 years. Of these monitored contaminants only 1,4-Dichlorobenzene has to-date been detected in LUS well water.
Table 2. This table lists the 34 contaminants known to be present at the abandoned railyard and not monitored/reported by LUS in untreated well water samples taken once every 3 years.