–Forwarded Message Attachment–
Subject: Monthly update for Sellers Auto / Artist Studio petroleum cleanup site 489201547 / 489201548 (Thirty-fifth update)
Date: Thu, 1 Oct 2009 14:42:45 -0400
CC: JRWebster@r-kidproperties.com; firstname.lastname@example.org; email@example.com; Carlos.Gonzalez2@ocfl.net; Renee.Parker@ocfl.net; firstname.lastname@example.org; email@example.com
October 1, 2009
I would like to take this opportunity to give you our thirty-fifth monthly update on the project.
The new work order to perform the pilot test and prepare the Remedial Action Plan Modification has been approved and Argus will very soon be scheduling the pilot test.
The system runtime during this quarter was less than the required 80% with the major cause of downtime attributed to the system being shut down due to the significant rains during this period. Argus reports that the saturated conditions in the vicinity of the gallery represent conditions out of their control. According to the historical weather reports for the month of May 2009, Orlando experienced excessive rainfall with as much as approximately 14 inches of rainfall, 10 inches above normal for that month. Between May and August 2009, the rainfall documented was over the historical averages for that period.
The amount of water treated between May and August was 1.58 million gallons, which is only a little lower than the range of groundwater treatment volume we have been seeing in recent quarters (approximately 1.6 to 2.4 million gallons per quarter). Several of the wells shut off where Groundwater Cleanup Target Levels were already reached.
Maintenance to the equipment is ongoing and Argus is working to resolve a problem with the system having the versatility to use either of the two vacuum blowers, to balance the use of each. During most of the life of the cleanup only one of the two vacuum blowers has been used. It isn’t feasible to operate both at the same time and it is best that the hours of each are balanced so both are being used and maintained.
The Year 3, Quarter 2 Operation & Maintenance Report is due at the end of October, and Argus should have it to us any day now. Today, I received the data through E-Mail that will be contained within this report and will summarize it in the milestone update below.
The new data summary follows: The approved RAPMod stated that the goals for this site are 90% reduction for the chemicals of concern (COC) to contaminant target levels (CTLs). Of the 12 monitor wells sampled, the following eight monitor wells: AW-3, AW-7, AW-11, AW-18, AW-22, AW-24, AW-25, and MW-6 currently are below Chapter 62-777, F.A.C., Table 1 Groundwater Cleanup Target Levels for all COCs analyzed. The remaining monitor wells: AW-10, MW-5, MW-9, and DW-11, had COCs above the CTLs. Of the four monitor wells with COCs currently exceeding CTLs, only one well (MW-5) is not meeting the milestones. In the last four or five quarters we hit a plateau with contaminants in a couple of monitoring wells near the sidewalk of the former Sellers Auto site is not reducing as rapidly as we’d like. Since the samples were collected with the remediation system operating, Argus believes that the groundwater elevations within the monitor wells were lower than the last sampling event and that this may cause the water table to be exposed to the smear zone and therefore, allow the COCs to leach into the water table from the surrounding exposed aquifer matrix. The may be one of the causes of the increase in COC concentrations at MW-5 in addition to the previously reported findings that there is additional contamination upgradient of MW-5 that might be sourcing this area. The key milestone monitor wells being monitored include: AW-3, AW-7, AW-11, AW-22, AW-24, and MW-5. An Air Sparge/Vapor Extraction pilot test is soon to be performed in addition to a Level 3 Remedial Action Plan Modification to implement system modifications that will address the additional contamination.
I look forward to providing the next update on November 2, 2009. Please feel free to call me anytime if you need additional information or have any questions.
Damon Taylor, Environmental Case Manager
CFEA # 408 / LEP # 201
Orange County Environmental Protection Division
800 N. Mercy Drive, Suite 4, Orlando, FL 32808
Direct (407) 836-1480, Main (407) 836-1400
Fax (407) 836-1417