SITE INFORMATION AND CORRESPONDENCE_FILE 2

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1✓ Nftw Moore Petroleum Page 2 of 3 5491 F Street August 28, 2012 Banta, California screened interval from 60 to 80 feet bsg. The Rhodes well is in the general down-gradient direction from the subject site. Except for the Rhodes well, the sensitive receptor surveys did not provide well logs or permits for wells on adjacent and some nearby sites, however, a table with total depths for the wells with logs in the area show 14 out of 33 wells with logs have total depths of 100 feet or less, and an additional 9 have total depths of 150 feet or less. It can reasonably be inferred that the wells on the adjacent properties that do not have driller's logs have likely total depths of less than 150 feet and probably less than 100 feet, and may pull in water from the above-mentioned sand interval. The EHD has considered the plume of impacted groundwater to be adequately delineated and declining, but given the sandy character of the subsurface in the area and the shallow total depths of many domestic wells in the area, the EHD has concluded that it is both necessary and prudent to sample the wells on the adjacent properties that have not been previously sampled before site closure is granted. On 23 August 2012 and 27 August 2012, the EHD discussed the situation of your site with Mr. Kirk Larson of the Five-Year Review Committee of the State Water Resources Control Board, who concurs that it is reasonable and necessary to sample the domestic wells in the area prior to site closure. The EHD therefore directs you to sample the following wells and to provide any obtainable information on the well construction; specifically, the EHD directs you to obtain permission and sample the following water supply wells: • the well serving the subject site • 5555 F Street (may be using 5535 F Street as the address) • 5573 F Street • 5554 F Street • 5440 F Street • 5481 F Street • 5389 F Street • 5490 F Street • 22701 S. Sixth Street • 22721 S. Sixth Street, and • 22550 S. Sixth Street If any contaminants of concern are detected in any of the wells, immediately resample the well(s) to confirm the initial result. The EHD visited several of the sites on 24 August, 2012, and the occupant of the property at 5490 W. F Street did not want to have his well tested for the fuel constituents, so access to some wells may be denied; please inform the EHD of each such access restriction. In addition to the above, sample monitoring wells MW-15 and MW-18 for total petroleum hydrocarbons quantified as gasoline (TPHg), diesel (TPHd), motor oil (TPHmo), BTEX and fuel oxygenates. MW-15 has generally been a 'non-detect' well, but had low, but increasing TPHd concentrations during the last three monitoring events. MW-18 was installed to test for TPHmo, but can be used to demonstrate the vertical extent of BTEX and the five oxygenates in the area immediately down-gradient and near a source area on the site. Domestic Well sampling Directive Letter 0812