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<br /> Elks Lodge Excavations Report
<br /> Page 2
<br /> ' million(ppm) in a sample from test pit 10 at a distance of approximately 55 feet north of the fence along
<br /> W. Sonora Street and from a depth of approximately six inches bgs. PID readings indicated the presence
<br /> ' of hydrocarbons in test pits 7, 10, 11, and 12 at concentrations ranging from 0.4 to 1.2 ppm. PID readings
<br /> were not taken in test pits 8 and 9. The top of the soil with the hydrocarbon odor was approximately six
<br /> inches bgs in the southern part of the site, and sloped gradually downward until it was approximately 18
<br /> ' inches bgs to the north.
<br /> Native soil was generally encountered at depths ranging from 2 '/2 to 4 feet bgs in the test pits. In the
<br /> south end of test pit 12, native soil was encountered at a depth of approximately six feet bgs. In this area
<br /> ' an approximately one-foot thick layer comprised primarily of glass was encountered at a depth of
<br /> approximately four feet bgs. The soil at the surface of the area is generally sand and gravel fill. In the area
<br /> of test pit 9, and at the eastern end of test pit 11, this fill has a gray color and appears to possibly consist
<br /> ' of road base material.
<br /> When beginning the excavation of test pit 9, starting at the south end of the excavation, the excavator
<br /> encountered a brick wall oriented north-south. The excavator moved approximately five feet to the west
<br /> to avoid this wall.
<br /> ' A total of 16 soil samples were collected from test pits 7, 10, 11, and 12 for the purpose of identifying the
<br /> soil contaminants and characterizing the degree and extent of the contamination. Composites of the
<br /> samples were prepared by GeoAnalytical Laboratories, Modesto California, before analyses were
<br /> ' performed. All of the composites were analyzed for benzene, toluene, ethyl benzene, and total xylenes
<br /> (BTEX) by EPA Method 8021B , for total recoverable petroleum hydrocarbons by EPA Method 418.1,
<br /> for total extractable hyrocarbons (TEPH) quantified as kerosene, diesel, and motor oil by EPA Method
<br /> 3550 LUFT , and for the CAM 17 Metals by EPA Methods 7041, 7471A, 7841, and 6010B. One
<br /> ' composite sample was analyzed for chromium (VI) by EPA Method 7196A. One discrete sample from
<br /> test pit 10 was analyzed for Volatile Organic Compounds (VOC) by EPA Method 8260B and for Semi-
<br /> VOC and polynucleated aromatics (PNAs) by EPA Method 8270C. The laboratory analytical results are
<br /> presented in Tables 1 - 4. Laboratory analytical methods used, reporting limits, results of analyses and a
<br /> copy of the chain-of-custody record for the soil samples are included as an attchment.
<br /> ' No semi-VOCs or PNAs were detected above the laboratory reporting limits in the discrete sample from
<br /> test pit 10. Ethyl benzene, tetrachloroethylene, toluene, trichloroethylene, m,p-xylene, o-xylene, 2-
<br /> butanone, 4-methyl-2-pentanone, acetone, 2-chlorotoluene, 4-chlorotoluene, p-isopropyltoluene, n-
<br /> ' propylbenzene, 1,2,4-trimethylbenzene, and 1,3,5-trimethylbenzene were detected in the discrete sample
<br /> from test pit 10. No chromium (VI) was detected above the laboratory reporting limits in the composite
<br /> sample tested for this analyte. Total xylenes were detected in one composite sample. No total extractable
<br /> hyrocarbons (TEPH) quantified as kerosene or diesel were detected above the laboratory reporting limits
<br /> ' in any composite sample. Total extractable hyrocarbons (TEPH) quantified as motor oil and total
<br /> recoverable petroleum hydrocarbons were detected in three composite samples. Arsenic, barium,
<br /> chromium, cobalt, copper, lead, nickel, vanadium, and zinc were detected in all four composite samples.
<br /> ' Cadmium was detected in three composite samples.
<br /> CONDOR
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