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Stantec August 15,2013 Page 5 of 8 h. Nuisance as defined by Water Code section 93050 does not exist at the site. Water Code section 93050 defines "nuisance" as anything which meets all of the following requirements: (9) Is injurious to health, or is indecent or offensive to the senses, or an obstruction to the free use of property, so as to interfere with the comfortable enjoyment of life or property. Petroleum-impacted soil likely remains onsite, however based on the location of these impacts (beneath the convenience store parking lot), the impacted soil will not be encountered by occupants of the property. (2) Affects at the same time an entire community or neighborhoods, or any considerable number of persons, although the extent of the annoyance or damage inflicted upon individuals may be unequal. The impact is limited to the 7-Eleven property. (3) Occurs during, or as a result of, the treatment or disposal of wastes. No treatment or disposal of wastes is currently being conducted at the site. Media-Specific Criteria 1. Groundwater The media-specific criteria for groundwater of the LTCP requires that "the contaminant plume that exceeds water quality objectives must be stable or decreasing in areal extent' and it must "meet all of the additional characteristics" of one of the five established classes of sites. Review of historical groundwater data collected from groundwater monitoring wells indicates that the hydrocarbon impacts to groundwater are well defined. The TPHg plume geometry from the second quarter 2013 is depicted with an isoconcentration map on Figure 4. A summary of groundwater flow directions and gradients is presented in Table 6 and Figure 5. In addition, review of the groundwater data indicates that the plume is historically stable. Outer wells MW-1, MW-5, MW-6, and MW-7 have not contained TPHg concentrations above laboratory reporting limits since the fourth quarter 2005. MtBE continues to be detected in well MW-6; however, concentrations have not exceeded 2.2 pg/L since sampling began in 2001. While TPHg continues to be detected in monitoring wells MW-3 and MW-4, decay rate calculations (included in Attachment B) indicate that TPHg concentrations will reach water quality objectives (100 pg/L) in a maximum of approximately 20 years. The contaminant plume at the site meets the characteristics of the first class of sites listed in the LTCP. Specifically: • The contaminant plume that exceeds water quality objectives is less than 100 feet in length (see Figure 4). • There is no free product present in any of the site-related groundwater monitoring wells. • The nearest existing water supply well or surface water body is greater than 250 feet from the defined plume boundary (Stantec 2005 Additional Site Assessment and Site Conceptual Modeo. V:\1857\active\7- Eleven\active\185750063_711_14117\05_report_del iv\reports\14117_2013_08_15_closu re_report.doc