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[KB Home’s Runkle Canyon development is now called Arroyo Vista at the Woodlands]

(Click here to see Geocon report on the DTSC website)

P. 5/150: “Analytical results of surface water samples collected from East and West Seeps in Fishtail Area that are not produced in a report. Samples were collected by Miller Brooks on April 5, 2005.”

P. 7/150: “Perchlorate was detected at a concentration of 0.33 micrograms per liter (μg/l) in a duplicate sample during the first sampling event. According to the laboratory this reported concentration should be considered suspect based on retention time drift and potential co-elution of an interfering constituent. None of the other samples or duplicate samples were reported to contain perchlorate.”

That equals 330 ppb in groundwater. Ahmanson was 28 ppb therefore Runkle is over 11 times more.

According to OEHHA at http://www.oehha.org/public_info/facts/perchloratefacts.html the Public Health Goal is 6 ppb in drinking water.

Runkle Canyon groundwater has tested as high as 55 times the Public Health Goal for perchlorate.

P. 7/150: “Historic pumping depressions at Rocketdyne have limited the movement of degraded groundwater beneath the property and have essentially confined the extent of known groundwater contamination to the area beneath the facility. Offsite migration of degraded groundwater has been identified in isolated areas along the northwest and eastern property boundaries. The perchlorate plume reportedly extends offsite of the facility to the east and southeast (southeast of the Runkle Site). The TCE in groundwater is reportedly present in several well-defined plumes that remain predominately beneath the Rocketdyne facility with a limited area offsite to the north of the western end of the property (west of the Runkle Site).”

The preceding contradicts itself on one of the biggest points – offsite migration of degraded groundwater. Which is it? If the lab doesn’t know, or does and decides to mischaracterize the situation even while contracting itself, the lab’s veracity is questionable.

P. 7/150: “Miller Brooks collected soil samples along the western border of the Site, adjacent to the Rocketdyne facility. Low concentrations of toluene, xylene, mercury, and dioxin were reported in several of the samples collected. The reported concentrations on these constituents were all below their respective PRGs.”

PP. 7-8/150: “Surface water and groundwater on the Runkle Canyon Site have been tested to evaluate the presence of constituents of concern potentially originating from the Rocketdyne facility. Samples have been collected from the on site stream and from a number of springs present on site. Water samples have been analyzed for TPH, VOCs, SVOCs, PCBs, perchlorate, NDMA, and metals. Perchlorate was reported in a duplicate groundwater sample as described above. NDMA was reported in one groundwater sample collected from an onsite monitoring well in July 2004, however the results should be considered suspect due to laboratory blank contamination. Subsequent groundwater samples collected from this well did not contain reportable concentrations of NDMA. No other reportable concentrations of other constituents were found in any of the water samples collected at the site with the exception of metals at concentrations typically found in groundwater.”

While quick to discount positive results for contaminants, Geocon isn’t as careful with its characterization of contaminants onsite. “Perchlorate was reported in a duplicate sample above” does not take into account several detections of it. The last sentence is false in two ways: TCE has been detected in the groundwater and the metals greatly exceed concentrations typically found in groundwater.

P. 8/150: “Based on the reported results Foster Wheeler concluded that the cesium-137 and strontium-90 concentrations reported in the samples were not a concern when compared to exposure limits considered by the EPA to be protective of human health.”

This sentence is literally true yet totally misleading as “Neighborhood Threat” shows. Yet another example of Geocon’s imaginative way of not analyzing results already ascertained by the developers’ lab but also mischaracterized. The numbers speak for themselves as our investigation has repeatedly shown.

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).”

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