Environmental Health Coalition Weighs in on Recent Chatham Reports

Environmental health experts at Environmental Health Coalition filed this comment letter today on the most recent monitoring reports on the Chatham contamination. EHC Chatham Comment Letter Feb 26 2015.
There is important information about 1,4-Dioxane and it speaks eloquently to several issues we are facing locally.  We are very grateful to EHC to their enduring commitment to community health.

Here are some excerpts

Regarding whether Natural Attenuation is occurring:

“The latest monitoring results do not provide evidence that natural attenuation is occurring.  Increased levels of TCE occur at sampling sites up and down Felicita Creek, including both the northern and southern portions. Not only are the levels not diminishing, this pattern of  monitoring results does not support the Hargis contention that levels in the more northerly part of the creek will diminish first, followed by levels in the down gradient portions of the creek and plume. In fact, these results show neither a short term nor a long term pattern of attenuation in TCE levels. Levels in FC-4, one of the wells in the northern part of Felicita Park, show an increasing trend over the 20-year period from 1994 through mid-2014, as charted in Figure 7 of the Hargis Technical Memorandum of January 16, 2015.
Another well in the northern area of the Park, FC11/11A, shows an increase since the previous round of monitoring in April 2014. Levels of TCE in MW-58 appear to be exactly the same in the most recent results as they were 15 years ago, in 2000, also shown in Figure 7.”
Regarding the length of time of the natural attenuation:

“Not only do these results fail to support the PRP consultant’s theory, the PRP group fails to provide any estimates of how long they expect this natural attenuation process to take. How long are they expecting Felicita Creek and groundwater to remain contaminated? How many more years are they asking Escondido families to be patient while upwelling of contaminants continues into their neighborhood park and their groundwater wells? A generation of children has grown up since the Chatham plume began its migration, and we’re still being told that attenuation will eventually occur. It is past time for DTSC to demand that the PRPs take additional action to remediate the plume, as well as to treat all wells that have measurable levels of chlorinated hydrocarbons or 1,4-dioxane.”

Regarding what the MCL does and doesn’t mean and a preference for the PHGs:

“Finally, we urge DTSC to bear in mind that MCLs are only as health protective as is technologically and economically feasible. They are not truly health protective standards, and it is inaccurate to state or imply that water meeting MCL levels is “safe.” In the case of TCE, which has both an MCL and a Public Health Goal (PHG), we urge you to use the PHG as the basis for decisions to post signs along the creek, and as a cleanup level for creek and well water.”

Regarding health information on 1,4-Dioxane


“Levels of other contaminants are also of continuing concern. 1, 4-Dioxane levels are high in several wells, including an all-time high of 100 μg/l in FC-04, a level 33 times the OEHHA public health notification level of 3 μg/l. This is of particular concern in a location where children may be exposed. 1,4-Dioxane has been listed on California’s Prop. 65 list as a carcinogen since 1988.  Most of the human toxicology of the substance derives from worker exposure; effects of low dose exposure to children are not known. Nor has OEHHA developed a child-specific reference dose for this compound. 1,4-Dioxane exposure can occur through dermal exposure as well as inhalation and ingestion — all plausible routes of exposure for children playing in or near the creek. In short, the possible impacts of exposing children to 1,4-dioxane are not known, and DTSC must act to protect children who visit the park.”

Please read this letter for yourself.  You will learn a lot.

If you are not already a member of this amazing group, please join!  You can find more information here Environmental Health Coalition

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s