P. 21/150: “Based on the odor, appearance, and the analytical laboratory results, the tar appears to be a petroleum-based substance; most likely “asphalt” or “asphalt cement”, a heavy petroleum product containing compounds with as many as 150 carbon atoms resulting from distillation of crude oil. Because the TPH extended range analysis is terminated at compounds containing approximately 40 carbon atoms, the reported analysis accounts for only 10% of the total mass of the sample.
The asphalt may have been used at the former aggregate mining operation to create asphaltic concrete for surfacing haul roads. The asphalt exposed in the stream channel is of limited lateral and vertical extent, though it may be possible that other deposits could exist elsewhere within the undocumented fill in the canyon. Geocon estimates that the volume of asphalt is approximately 12 cubic yards or less. Based on the analyses performed and the quantity of material, it is our opinion that this material does not represent an REC. In its present condition, the asphalt would not be suitable for use in fill and should be removed from the site and disposed of at a recycling facility or possibly at a Class III landfill if in solid form.”
EnviroReporter.com recommends that the petroleum-based substance, with high benzene content, be analyzed for the approximately 110 other carbon atoms, or 90% of the total mass of the sample that remains unaccounted for. We also concur with Geocon that this material be removed from the site and disposed of properly after it is correctly analyzed in DTSC’s lab and characterized in situ to determine its lateral and vertical extent.
P. 77/150: Test results of Polynuclear Aromatic Hydrocarbons include a result of 24.3 mg/kg for benzo(a)antracene which is 39.19 times its PRG of 0.62 mg/kg.
*1H. Could DTSC respond in detail to the above observations?*
1I. August 1, 2005: “Runkle Canyon_Dade Moeller_Supplemental Soil Sampling for Strontium-90_82005” available at http://www.envirostor.dtsc.ca.gov/public/community_involvement/3576535880/Runkle%20Canyon_Dade%20Moeller_Supplemental%20Soil%20Sampling%20for%20Strontium-90_82005.pdf
The results of this testing were analyzed in the January 19, 2006 article for Los Angeles ValleyBeat entitled “Hot Property.” As the article notes:
The retested locations were all radically lower in Sr-90 than in the previous tests conducted by GreenPark Runkle. In one spot tested, the state lab’s results were 490 times lower for Sr-90 than when it was tested in a 1999 survey. Oddly, the CDHS results for Sr-90 were from two-to-19 times less than the exact same split samples analyzed by Dade Moeller.
Each one of Dade Moeller’s readings is above Sr-90’s natural background at Runkle Canyon and even though that lab’s reading for the previously known hottest spot on the property is lower by nearly 30 times, it is still over eight times the background and nearly twice the EPA’s preliminary remediation goal for Sr-90.
EnviroReporter.com maintains that this Dade Moeller report not only was based on too few samples, but that it is highly inaccurate as well.
*1I. Could DTSC respond in detail to the above observations?*
1J. April 1, 2005: “Runkle Canyon_Dade Moeller_Sr-90 Radiological Health Risks Assessment- 042005” available at http://www.envirostor.dtsc.ca.gov/public/community_involvement/1879697501/Runkle%20Canyon_Dade%20Moeller_Sr-90%20Radiological%20Health%20Risks%20Assessment-%20042005.pdf
On page 14 of this 32-page PDF states “[The] risk to a typical Runkle Canyon resident would be much less than the target 1 x 10(-6) risk level and even less than 1 x 10(-7).” On page 15, Dade Moeller claims the result for residents who do not ingest soil or eat homegrown produce would be “closer to 2 x 10(-8). On page 16, the report states that an “open space” user’s “risk would be less than 1 x 10(-8).” On page 17, Dade Moeller asserts that for neighbors exposed to the dust of Runkle Canyon construction “would be 3.1 x 10(-10).
These estimations, not fully calculated in Dade Moeller’s report, do not jive with CDHS’ response to questions posed by the Radiation Rangers to the department. In an April 10, 2007 letter, CDHS states “[T]his soil concentration equates to approximately 5E-6 (5 in a million] cancer risk for future site residents using the EPA PRG…”
This means that, despite the unexplained math, Dade Moeller underestimates the cancer risk that CDHS calculates by factors ranging from 50 to 16,129 times. EnviroReporter.com maintains that Dade Moeller’s estimations are highly inaccurate and should not be used to estimate cancer risks for residents, open space users or neighbors exposed to construction dust of Runkle Canyon’s proposed development.
*1J. Could DTSC respond in detail to the above observations?*
1K. July 29, 2004: “Runkle Canyon_Miller Brooks_Supplemental Site Assessment Rpt Groundwater_72904” available at http://www.envirostor.dtsc.ca.gov/public/community_involvement/7901303946/Runkle%20Canyon_Miller%20Brooks_Supplemental%20Site%20Assessment%20Rpt%20Groundwater_72904.PDF
On page 3 of this 93-page PDF, the report states: The samples collected from Well MW-I (MW-1 and DUP- 1 were reported to contain concentrations of NDMA at 3.2 nanograms per liter ng/L and 3.5 ng/L respectively. The data assessment stated that the concentrations of NDMA reported in the samples collected from Well MW-I should be considered suspect based on method blank contamination and internal standard failures.
EnviroReporter.com observes that this lab, and other labs used by the developers, have repeatedly discounted positive hits for contaminants as laboratory error which we find highly questionable.
*1K. Could DTSC respond in detail to the above observations?*
1L. March 31, 2004: “Runkle Canyon_Miller Brooks_Source Evaluation Report_33104” available at http://www.envirostor.dtsc.ca.gov/public/community_involvement/3674588859/Runkle%20Canyon_Miller%20Brooks_Source%20Evaluation%20Report_33104.PDF
Page 2 of this 50-page PDF state that the “SSFL facility is located at a higher topographic elevation than the [Runkle Canyon] Property; however, a steep ridgeline separates the facility from the Property (EDR, 2003).”
This is highly misleading. While indeed a steep ridgeline separates some of the lab from Runkle Canyon, a well-established 11-acre drainage leads off of Area IV of Rocketdyne leading directly down into Runkle Canyon.
This report does contain an excellent historical summary for Runkle Canyon stretching all the way back to the time of the Chumash.
*1L. Could DTSC respond in detail to the above observations?*
1M. March 31, 2004: “Runkle Canyon_Miller Brooks_Groundwater Investigation Workplan_33104” available at http://www.envirostor.dtsc.ca.gov/public/community_involvement/3894864737/Runkle%20Canyon_Miller%20Brooks_Groundwater%20Investigation%20Workplan_33104.PDF
On page 3 of this 26 page PDF, it states: No concentrations of perchlorate were detected in any of the water samples analyzed. Perchlorate was only detected in two groundwater/silt samples collected from Borings HS-25 and HS-26 samples HS-25-56 and HS-26-37. The concentrations detected were at 0.06 milligrams per kilogram (mg/kg) and 0.05 mg/kg respectively These levels are below the EPA’s Preliminary Remediation Goals for perchlorate in residential soil (7.8 mg/kg USEPA 2001/2002).
This is highly misleading and deceptive. The perchlorate was found in the Runkle Canyon groundwater of the groundwater/silt samples therefore to use PRGs for residential soil is not appropriate. Water standards show that the 0.06 mg/kg, or 60 ppb, exceeds the Public Health Goal in tap water by a factor of ten times.
*1M. Could DTSC respond in detail to the above observations?*