From: FORTUNA Steve
Sent: Mon Mar 15 15:43:13 2010
To: SEIDEL Paul
Cc: FORTUNA Steve
Subject: City of Fairview well contamination
Importance: Normal
Hi, Paul.
Last week, Keith approved a memo I prepared summarizing potential sources of the contamination detected in the City of Fairview wells. Copies of the memo are available in my V:\ drive project files under FairviewMemoRev (text as a .docx file; text and figures as a .pdf file)
In the memo, I’ve listed about ½ dozen potential sources for the PCE/TCE/1,1,1-TCA contamination detected in the city wells. I am initiating PAs on the first two of the potential PCE sources at this time.
But the city wells are also contaminated with ethylene dibromide (EDB) at concentrations that have sometimes exceeded Drinking Water MCLs (and certainly exceeded residential and urban residential drinking water RBCs).
It appeared very unlikely to me that the EDB source could be associated with either dry-cleaning operations or leaded gasoline:
· commercial use of leaded gasoline was banned in January 1986;
· EDB was probably not used in leaded gasoline after 1982 because its potential threat to drinking water was already well-understood, and a substitute had been found by then;
· when in use, EDB was only added to leaded gasoline at less than about 1,000-ppm (concentrations far too low to produce DNAPL);
· only transient traces of BTEX have been detected in the city wells (BTEX should have been present in the gasoline (and groundwater) at much higher concentrations than EDB).
I concluded that the most likely source for EDB was agricultural operations, and proposed Townsend Farms as a potential source:
· Townsend Farms grew the types of crops that used EDB most commonly (berries and root crops);
· EDB had also been specified for used as a post-harvest fumigant for vegetable and berry crops;
· Traces of EDB and 1,1,1-TCA had previously been detected in the Townsend Farms wells.
While it’s true that there could be any number of potential sources for EDB in the local aquifer (including illegal disposals on vacant land), I concluded that Townsend Farms is the most obvious candidate at this time.
Addressing potential PCE sources alone will probably do nothing ameliorate potential health-related issues for the City of Fairview drinking water. I recommended to Keith that Townsend Farms concurrently be examined as a potential source for the EDB contamination detected in local groundwater. Since Townsend Farms is an active Cleanup site, I felt it might be most expeditious to address this issue through the current Cleanup project.
Let me know what you think.
Steve Fortuna
Site Assessment Specialist
DEQ Northwest Region
2020 SW 4th Avenue, Suite 400
Portland, OR 97201-4987
503-229-5166
FAX: 503-229-6945
e-mail: fortuna.steve@deq.state.or.us
Be sure to visit DEQ's Cleanup Program at: