P. 8/150: “In 2000 Harding ESE collected an additional fourteen samples from the 715-acre parcel of the Site, two samples from the 350-acre parcel, and one just east of the 550-acre parcel to evaluate the presence of radionuclides. Based on the results Harding concluded that the property was not likely contaminated with tritium or cesium-137. They were unable to make a definitive conclusion regarding strontium-90 and recommended further sampling.”
This conclusion will be addressed in EnviroReporter.com‘s analysis of the 2000 Harding ESE.
PP. 8-9/150: “In 2003 Miller Brooks collected an additional 27 soil samples from the Site and three from offsite that were evaluated for strontium-90. Only two of the soil samples contained detectible concentrations of strontium-90. Based on this data Miller Brooks concluded that reported concentrations were below levels considered to pose a health risk. Groundwater and surface water samples collected during these investigations were analyzed for tritium. The reported concentrations of tritium in the water samples were concluded to be below levels considered by regulatory agencies to pose a health risk.”
This is a notable instance where Geocon cites this study, repeatedly stating that samples were concluded to “be below levels considered by regulatory agencies to pose a health risk,” yet in the very next summation notes that the lab Dade Moeller didn’t include the 2003 Miller Brooks study because “the higher minimum detectable activity reported by the laboratory.” This misleading Geocon entry also fails to note that the city of Simi Valley used this 2003 Miller Brooks study as the basis of its EIR.
P. 9/150: “In all cases the risk was calculated to be less than the target risk level of one in one million (1 X 10-6).”
This is indeed the “target risk level,” which the California Department of Health Services (CDHS) later determined to be nearly five times that from strontium-90 in the site’s soil. The Runkle Canyon EIR, however, states that this risk is 0.77 in a million, a figure later amended, without explanation, to 0.26 in a million, or 1/18th of what CDHS says. These are more instances of the developers’ labs basically asserting safety levels not based on ascertainable fact.
P. 11/150: “Benzene, toluene, and ethylbenzene were detected at concentrations of 35, 62, and 27 micrograms per kilogram (μg/kg). No additional VOCs were detected at or above laboratory detection limits (ND). The United States Environmental Protection Agency, Region 9, residential Preliminary Remediation Goals (PRGs) for benzene, toluene, and ethylbenzene in soil are 640 μg/kg, 520,000 μg/kg, and 400,000 μg/kg, respectively. None of the reported concentrations exceed their respective PRGs. No additional VOCs were detected at or above laboratory detection limits (ND).”
In the preceding paragraph and on page 20/150 of the report’s PDF, Geocon writes “micrograms per kilogram (μg/kg)” which is incorrect. The designation “μg/kg” indicates parts per billion. We cannot explain this basic mistake but it does fit with a pattern in the body of Geocon reports presented by KB Home to DTSC that contain inaccuracies, omissions and incorrect conclusions, all of which undermine confidence in the developers’ conclusions about the environmental conditions at the site.
P. 17/150: “Groundwater contamination originating on the Rocketdyne facility reportedly has migrated offsite to the southeast, into the San Fernando Valley, and to the north, east of Runkle Canyon, into Simi Valley. Based on the reported magnitude and direction of degraded groundwater originating from the Rocketdyne facility and the results of soil, surface water, and groundwater samples collected from within Runkle Canyon it does not appear that the historic sources originating from the Rocketdyne facility are adversely affecting the Runkle property.”
This unsubstantiated statement is not supported by the facts of tests before and after this report was created. Indeed, we reported this several months before this report in “Neighborhood Threat” where we wrote:
In December 1998, when GreenPark began its environmental investigation of the property, the developer hired Phoenix-based QST Environmental to do preliminary soil sampling of the canyon to see if the former Rocketdyne lab “had impacted on-site soils, based on surface run-off carrying radionuclides to the site.” The results “indicated the presence of Strontium in all samples collected … that exceeded the EPA average local background concentration.” Indeed, the four soil samples contained up to 17 times the amount of the radionuclide that the EPA says is naturally occurring in the area. “Based on the analytical results of the soil samples, it would appear that there may have been some impact of radionuclides to the site from the Rocketdyne facility,” the report said.
P. 18/150: “Geocon contacted the Los Angeles Regional Water Quality Control Board (RWQCB) to inquire on the status of groundwater investigations being performed at Runkle Canyon. According to department staff, the RWQCB is not currently overseeing any programs at the Site. The RWQCB did request that Green Park sample and provide groundwater data; however, an order was never issued by the board.”
The RWQCB seems remiss in its request for groundwater sampling and data that was not acted upon. The Radiation Rangers have expressed concern that DTSC might also not fully investigate the site’s groundwater but are still withholding judgment.
P. 19/150: “Based on the results of results of the surface and groundwater sampling performed on the Site it does not appear that the degraded groundwater reportedly present on the Rockerdyne [sic] facility is migrating onto the Runkle Site.”
This conclusion is incorrect: Runkle Canyon groundwater has had significant detections of perchlorate, NDMA and TCE. Also, as our story “The Radiation Rangers” shows, the developer did not test surface waters of the canyon’s stream at the time of this report’s issuance so any characterization of the surface water is speculative and false. It is worth noting that Geocon uses the conditional phrase “does not appear” which makes the entire statement speculative versus definitive.
P. 19/150: “Concentrations of TPH in the diesel to motor oil range, ranging from 14 mg/kg to 320 mg/kg, were reported in five of the samples analyzed. The metals concentrations reported in the soil appear to be at background concentrations, with the exception of two samples reported to contain mercury at concentrations of 0.22 and 0.24 mg/kg. The Preliminary Remediation Goal (PRG) for mercury in residential soil is 23 mg/kg.”
EnviroReporter.com wasn’t aware of these results until reading this. The significance of the results isn’t analyzed as far noting how far above background the mercury is or the relative significance of the TPH results.
P. 20/150: “The report concludes that construction and operation of the proposed Runkle Canyon Development would result in very low radiological risk from strontium-90 exposure to residents, visitors, and neighbors. In all cases the risk was calculated to be less than the target risk level of one in one million (1×10-6).”
The California Department of Health Services has concluded that the strontium-90 in Runkle Canyon soil and dust would create a cancer risk nearly five times this, at about 5 x 10-6.
P. 20/150: “Geocon analyzed a sample of the tarry material for total petroleum hydrocarbons (TPH) extended range by modified EPA method 8015B, volatile organic compounds (VOCs) by EPA method 8260B, and polycyclic aromatic hydrocarbons (PAHs) by EPA method 8310. The sample exhibits a total combined TPH concentration of 102,130 mg/kg. Benzene, toluene, and ethylbenzene were detected at concentrations of 35, 62, and 27 micrograms per kilogram (µg/kg). No additional VOCs were detected at or above laboratory detection limits (ND). PAHs were detected at individual concentrations up to 24.3 mg/kg.”
EnviroReporter.com was not aware of this report or these results. Neither, we suppose, was the city of Simi Valley or its residents. We note that the benzene in this tarry material found in Runkle Canyon is nearly 55 times its PRG for residential soil, the limit of which is 0.62 mg/kg and that, according to the EPA’s 2004 PRG list for contaminants, exceeds the chronic, 100% chance of contracting a cancer from this substance which is 33 k/g/mg.
P. 21/150 : Under “Conclusions and Recommendations”: The Rocketdyne facility located to the east of the southern 715 acre parcel is reportedly the origin of groundwater plumes of degraded groundwater, containing perchlorate and TCE, that have migrated offsite to the east and southeast of the Runkle Site. Based on the reported magnitude and direction of degraded groundwater originating from the Rocketdyne facility and the results of soil, surface water, and groundwater samples collected from within Runkle Canyon it does not appear that the historic sources originating from the Rocketdyne facility are adversely affecting the Runkle property. Further evaluation of chemicals of concern potentially originating from the Rocketdyne facility appears unwarranted at this time.”
This conclusion is questionable. TCE, which has a plume of subsurface contamination in Area IV above the 11-acre drainage into Runkle Canyon, has been detected in Runkle Canyon groundwater. Perchlorate has been detected in the site’s groundwater at levels ranging up to double to 11 times what was found under adjacent Ahmanson Ranch and 55 times the Public Health Goal. The surface water has been impacted by high levels of arsenic, chromium, nickel, vanadium, barium, cadmium and lead. The surface soil has high levels of some of these heavy metals as well as strontium-90.
This Geocon report says it examined other reports to help form the conclusion that these substances aren’t coming from Rocketdyne and don’t need to be further evaluated. Apparently, Geocon did not read these reports as carefully as EnviroReporter.com has or it would have noted that in the May 8, 2003 Miller Brooks Phase I & II report performed for GreenPark Runkle, it says regarding perchlorate: “The source is thought to be the SSFL facility.”
P. 21/150: “Previous health risk assessments conducted by the property owner have concluded that the reported concentrations at the Site pose a low radiological risk to residents, visitors, and neighbors. In all cases the risk was calculated to be less than the target risk level of one in one million (1 X 10-6).”
As previously noted, the CDHS calculates the risk from strontium-90 in Runkle Canyon soil and dust to be nearly five in a million.
But if the “assessments conducted by the property owner” are to be the only source of information, that would include the Foster Wheeler report’s 58 soil samples which averaged 1.39 pCi/g, or six times the EPA’s preliminary remediation goal and nearly 46 times above the typical EPA background level for Sr-90 in the area. The hottest sampling spot, and the one closest to Rocketdyne’s Santa Susana Field Laboratory, measured 12.34 pCi/g, which is over 54 times the EPA’s PRG and 411 times the normal background for the radionuclide.
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