Operational History. Describe in detail how facility operations, processes and products have changed over time (historical aerial photographs could be useful for this purpose).
Operational History. The City of Keizer supplies approximately 33,000 residents with water from a municipal well field located in Keizer city limits. In July 2002 during routine monitoring, the City of Keizer detected PCE in groundwater samples collected from two of its oldest and shallowest municipal drinking water xxxxx (well #3 and well #4 – see Figure 4 for these xxxxx’ locations). PCE concentrations in these two xxxxx ranged from 0.4 to 6.2 µg/L. These xxxxx were shut down and decommissioned because of the solvent contamination. The City of Keizer continues to rely on groundwater for it’s water supply and screens all xxxxx against the federal drinking water standard (maximum contaminant levels [MCLs]). While all of Keizer has municipal water service available, some residents rely on individual domestic xxxxx for their household water supply. Prior to conducting the PA, DEQ sampled several domestic xxxxx near the impacted municipal xxxxx. The solvents detected in the samples were PCE, TCE, and cis-1,2-dichloroethene (cis-1,2-DCE). PCE was detected in 13 domestic xxxxx ranging from 1.0 to 77.2 µg/l. TCE was detected in 41 domestic xxxxx ranging from 1.22 to 25.4 µg/L. The generalized location of the shallow PCE plume, based on existing domestic well sampling, is shown in Figure 1. (See Appendix A for domestic sampling results.) DEQ compared the sample results to DEQ RBCs, EPA’s Region 9 Preliminary Remediation Goals (PRGs) and to the MCLs. Thirteen residential xxxxx contained PCE above the tap water PRG of 0.1 μg/l. Forty-one of the residential xxxxx contained TCE above the tap water PRG of 0.028 μg/L. Six residential xxxxx contained PCE above the MCL of 5 μg/L. Fifteen of the residential xxxxx contained TCE above the MCL of 5 μg/l. To protect the residents’ health, DEQ offered to connect affected residences above RBCs to city water. In the fall of 2004, 32 of 41 homes elected to be connected to city water. Two municipal xxxxx (well #1 and well #6) have had sporadic detections of TCE below the MCL (less than 2 μg/L) between 2002 and 2007. One municipal well (well #3) had a PCE detection (6.2 μg/l) above the MCL. The municipal well #3 was decommissioned in 2004due to solvent contamination and other maintenance issues. The focus of the SI was to identify PCE sources and to further define the extent of PCE contamination in groundwater. The source of PCE was not identified during initial site discovery work or the PA. However, many dry cleaners have used PCE as their primary cl...
Operational History. In July 2001, the solvent TCE was discovered in a residential well at 0000 Xxxxx Xxxxxx, Corvallis, when the owner had his well tested for a comprehensive list of chemicals. The owner contacted DEQ to report the TCE contamination in his well. In order to address the immediate health risks to residents with drinking water xxxxx, DEQ tested 13 water xxxxx in the area for volatile organic compounds (VOCs) along Xxxxx Street, Xxxxxxx Avenue, and Xxxxxxxx Avenue. The xxxxx having TCE were located along Xxxxx Street. TCE concentrations in those xxxxx ranged from 0.7 to 60 μg/l. (See Appendix A for sampling results.) DEQ compared the sample results to our risk- based concentrations (RBCs - screening levels from the Risk-Based Decision Making for the Remediation of Petroleum-Contaminated Sites guidance). The five residential xxxxx along Xxxxx Street having detected levels of TCE exceeded the TCE tap water RBC of 0.029 μg/l. To protect the residents’ health, DEQ installed carbon- treatment units on the five contaminated xxxxx to remove the TCE. Xxxxx Street - PA 1 July 28, 2003 CERCLIS No. ORN001002357 In March 2002, DEQ resampled 5 residential xxxxx along Xxxxx Street. TCE concentrations ranged from 0.1 to 190 μg/l. (See Appendix A for sampling results.) TCE concentrations had significantly increased in the residential well at 0000 Xxxxx Xxxxxx. Concentrations ranged from 24 μg/l in July 2001 to 190 μg/l in March 2002. DEQ was concerned that without carbon filters removing the TCE, residents would be exposed to unsafe levels of TCE in their well water. The source of TCE was unknown. DEQ has identified three possible sources: Xxxxxx County Shops, WPRR railroad, and residential shops (i.e., auto-repair and similar activities occurring at residences). The following operational histories describe the potential sources of TCE.
Operational History. 3.A Current use of source property. The following refers to only the source property and not other properties affected by the site contamination. Add information to the best of your ability.
Operational History. The site was reportedly used as an above ground landfill by immigrants in the early 1900s and subsequently by other residents till the pre-1950s. The site was consolidated and capped by the City in the mid-1990s. Glass bottles and porcelain were the primary items encountered during test pit explorations. The site use prior to the reported use in the early 1900s is unknown. A report documenting a classroom field excise for archaeology was submitted, by DEQ, to the State Historic Preservation Office (SHPO) for evaluation. SHPO indicated the report did not provide information to establish that the site was an archaeological site. The City of La Grande did not have any information on the historic site use. Copies of letters documenting these findings are presented in Appendix A.
