ARCHIVED REPORTS_XR0010760 - Laserfiche WebLink

Home Browse Search

Mr Harlan Knoll, R E H S November 28, 2005 Page 2 • 2 0 MONITORING WELL PURGING AND SAMPLING Monitoring well purging and sampling occurred on October 19, 2005 for the Fourth Quarter 2005 event. Only two of the wells are monitored MW-3 and MW-4 The momtoring wells were purged with a 12-volt battery operated submersible pump and sampled with a discharge rate of less than 1 L/mmute Field measured water quality parameters were measured using a Cambridge Scientific Industries HydacTm Conductivity Temperature pH Tester The appropriate information was logged onto the field sampling forms Well purging activities and the field measured water quality parameters are documented on the forms included in Attachment A Groundwater samples from each well were collected into four 40-mL glass vials with Teflon septum lids Following sample collection, each sample bottle was labeled with the sample designation,date and time, and the initials of the sampler The sample bottles were then placed into an ice chest maintained at the temperature available from its also containing a bed of crushed ice, and its melt water, placed there at the start of the sampling day The ice was not allowed to completely melt before it was replaced The sample number, date, and time was entered onto a chain-of-custody form that included the • request for analysis of Total Petroleum Hydrocarbons in the gasoline range(TPH-g); the volatile aromatic hydrocarbon compounds (benzene,toluene, ethylbenzene, and total xylene isomers), the fuel oxygenates tertiary-Butyl alcohol (TBA), Methyl tertiary-butyl ether(MtBE), Di- isopropyl Ether(DIPE), Ethyl tertiary-butyl ether(EtBE), and tertiary-Amyl methyl ether (TAME) and the scavengers ethylene dibrom:de(EDB) and 1,2-Dichloroethane(DCA)by U S E P A Method 8260B The samples and chain-of-custody documentation were then delivered to STL San Francisco (CA DHS ELAP#2496)of Pleasanton, California on October 19, 2005. 3 0 GROUNDWATER ANALYTICAL RESULTS Copies of the laboratory analytical reports prepared by STL San Francisco and the chain-of- custody documentation are contamed in Attachment B All available previous analytical data from 1990 through 2000 are summarized in Attachment C and from 2001 through the present data set are summanzed in Attachment E in Table E I Groundwater from MW-3 was reported with 64 pg/L TPH-gasoline Benzene was reported as 0 59 µg/L The other aromatic hydrocarbons(toluene, ethylbenzene, and total xylene isomers) were reported at the levels as listed in Table 3 MtBE was reported at 0 65 µg/L The other Method 8260B fuel oxygenates were reported as "N D " at their respective reporting knits. H2OGEOL AGROUNDWATER CONSULTANCY