West Central Phoenix (WCP) North Canal Plume
The WCP North Canal Plume WQARF site is bounded approximately by Indian School Road to the north, 33rd Avenue to the east, West Flower Street to the south and 43rd Avenue to the west in Phoenix, Arizona.
The final remedial investigation (RI) report is being completed and data has been collected for the Land and Water Use report.
1952: The former Southwest Metals facility was located near 36th Avenue and Clarendon Avenue. Southwest Metals operated at this property until 1973. The manufacturing process at the site consisted of constructing sand casts to form magnesium, aluminum, and brass castings.
1956: The former Osborn Products facility was located near 36th Avenue and Clarendon Avenue. Osborn Products operated at the site until 1984. Facility operations included chrome plating, machining, and grinding of parts for the aerospace industry. On-site processes included degreasing metal parts, chrome plating, and machining of parts to specification.
1963: The Precise/Paraflex facility is located near 39th Avenue and Clarendon Avenue. Precise/Paraflex and three subsidiary companies; Precision Marking, Paint Spray, Inc., and Perigee Metal Spinning, all operate at this facility.
1977 - 1989: The former Magic Metals facility was located near 36th Avenue and Whitton Avenue. Magic Metals operated at the site until 1987 when the facility was abandoned by the company. Principal business activities of Magic Metals included electroplating for automobiles, custom restorations, industrial parts, and antiques. The facility generated waste electroplating baths and rinses containing cyanide, waste caustics and unspecified waste solvents from stripping tanks, and waste acids (sulfuric and chromic). Those tanks were excavated and removed from the facility in 1989.
1982 - 1989: Volatile organic compounds (VOCs) were first detected in groundwater in the WCP area in July 1982. The City of Phoenix (COP) detected trichloroethene (TCE) in four municipal public supply wells, COP wells #70, #71, #151, and #152. The Arizona Department of Health Services, Salt River Project, and the COP confirmed the presence of VOCs in the groundwater with sampling in 1983, 1985, and 1986. Groundwater from COP wells #70 and #71 contained the highest concentrations of TCE and, therefore, were immediately shut down. Wells #151 and #152 were monitored for VOC concentrations from 1982 until 1989. As a result of sampling conducted during February of 1989, COP elected to take both wells #151 and #152 off-line on March 7, 1989.
Field investigation activities for the site began in 1984. Several contaminants were detected in soil and groundwater samples collected during field investigations at the four facilities. The primary contaminants of concern found were tetrachloroethene (PCE), TCE, 1,1-dichloroethene (1,1-DCE) and chromium.
1987 - 2000: In 1987, the WCP area was designated a WQARF priority list site. In 1997, ADEQ established the WQARF Registry which replaced the priority list. The site was placed on the WQARF Registry in June 1998, with a score of 22 out of a possible 120. The site score was re-evaluated in 2000, with a revised score of 27.
2005: An interim RI report documenting all activities was issued in August.
2006: The second early response action (ERA) evaluation and technical report was issued in October. Several facilities were identified as likely sources of the groundwater contamination in the site. The facilities included, but were not limited to: the former Osborn Products facility, former Magic Metals facility, former Southwest Metals facility, and Precise Metal Products/Paraflex Tool & Machine (Precise/Paraflex). Other facilities were being investigated as potential sources of groundwater contamination at the site.
2007: An aquifer test was carried out in September at the former Southwest Metals facility to help determine potential groundwater treatment options for the regional groundwater plume. Additionally, ADEQ conducted a soil vapor extraction (SVE) pilot test in February at the former Osborn Products facility. Based on the concentrations from the pilot test, the results did not merit a soil remediation system at that time.
2008: Soil vapor samples were taken across two areas at the site to aide in the placement of new monitor wells. As a result of samples taken earlier in the year, additional soil vapor samples were taken. Results of these sample events will be incorporated in the final RI report.
2009: Work on the draft RI report continued through the collection of information needed to compile a Land and Water Use report. Questionnaires were sent to various stakeholders, property owners and water providers.
2013: The well network (44 wells) was cleaned up for groundwater monitoring and sampling. Depth to water was measured in each well and groundwater samples were collected and analyzed for VOCs, chlorinated hydrocarbons and total chromium. Results indicated that the plume may be moving in a southern direction.
ADEQ USTs’ Program State Lead Unit installed 26 wells and a soil vapor extraction (SVE)/air sparge remediation system at the former TRIAD property.
2014: ADEQ monitored and sampled groundwater in February, monitored water levels in May and June to study effects on groundwater by SRP wells, and conducted a passive soil gas survey along 33rd Avenue. Data indicate that TCE concentrations in the vicinity of the former Triad property declined; the plume may be moving in a southern direction; and pumping SRP wells appears to effect water levels in the North Canal Plume (NCP).
2015: Groundwater monitoring and sampling was conducted in February 2015. A soil vapor partition test and limited passive soil-gas survey was conducted in the East Plume to evaluate the area for local sources of contamination.
To date, testing in the WCP area indicates no exposure to the contamination. Sampling shows that the contaminated soils are under asphalt parking lots or asphalt-surfaced storage areas, or under the concrete floors of buildings. Contaminated drinking water wells in the area have been shut down. In addition, notices have been sent out to all known residences within the WCP area for the testing of domestic wells for contamination.
Depth to groundwater has declined considerably in the past several years. This is attributed principally to the lining of the Grand Canal and the ongoing drought. In 1996, the depth to groundwater was approximately 70 feet below ground surface (bgs) adjacent to the canal and approximately 79 feet bgs approximately 900 feet north of the canal. By 2002, the mound had dissipated, and the depth to groundwater was approximately 120 feet bgs. Prior to lining the canal, the groundwater flow direction varied from the north to the northwest beneath the site. After lining the canal, groundwater flowed to the south beneath the site. Depth to water in the area as of February 2014 was between 125 feet and 151 feet bgs.
*In Arizona, but outside the Phoenix area, call toll-free at (800) 234-5677.
Interested parties can review site information here on this page and at the ADEQ Record Center located at 1110 W. Washington Street, Phoenix, Arizona. Please contact (602) 771-4380 or (800) 234-5677 ext. 6027714380 for hours of operation and to schedule an appointment. To review site information at a location near you, please contact the designated Community Involvement Coordinator.