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TABLE 1 - EVALUATION OF LOW THREAT UNDERGROUND STORAGE TANK CASE CLOSURE POLICY CRITERIA Criteria Meets Criteria? Comment General Criteria The general criteria established by the SWRCB under Resolution No. 2012.0016 that must be satisfied by candidate sites are as follows: a. The unauthorized release Is located within the The site is located in the City of Santa Ana, where water utility service service area of a public water system. Yes is owned and operated by the City of Santa Ana for public service. Id. The unauthorized release consists only of The unauthorized release is from multiple gasoline underground petroleum. Yes storage tank leaks that was identified in February 1988. c. The unauthorized release from the UST system Multiple USTs were removed in June 1988, which were the cause of has been stopped. Yes the unauthorized release of gasoline to the subsurface. d. Free product has been removed to the Free product has not been a concern at the site. Contamination in soil maximum extent practicable. and groundwater has been remediated through excavation of soils in Yes the tank cavities in 1988, operation of an SVE system between 1994 and 1996, application of ORC to the subsurface in 1999, and two HVDPE events In 2000 and 2003. e. A conceptual site model that assesses the A soil vapor survey and health risk assessment was conducted in nature, extent, and mobility of the release has 2013, which developed a conceptual site model and summarized been developed. Yes potential risks to on-site workers and nearby residences. Health risks to receptors were determined to be negligible f. Secondary source has been removed to the The secondary soil source has been removed to the extent extent practicable. practicable. However there are still residual soil impacts (as indicating Yes from confirmation soil borings) that may need to be left in place g. Soil and groundwater have been tested for MTBE has been tested in soil and groundwater for many different methyl tert-butyl ether (MTBE) and results investigations and monitoring reports. Currently, the maximum reported In accordance with Health and Safely Yes concentrations of MTBE detected is 1.5 pg/I in groundwater, which is Code section 25296.15. below the MCL of 13 pg/l. h. Nuisance as defined by Water Code Section Under the California Water Code, section 13050(m), nuisance means 13050 does not exist at the site. anything which meets all of the following requirements: 1. 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, 2. Affects at the same time an entire community or neighborhood, or Yes any considerable number of persons, although the extent of the annoyance or damage inflicted upon individuals may be unequal, 3. Occurs during, or as a result of, the treatment or disposal of wastes. Based on a review of historical documents, a nuisance is not applicable to the site contamination. Media—Specific Criteria Media—specific criteria established by the SWRCB under Resolution No. 2012-0016 that must be satisfied by candidate sites are as follows. Candidates must satisfy the criteria for the three medias of concern: (1) groundwater, (2) vapor Intrusion to Indoor air, (3) direct contact and outdoor air exposure. 1. Groundwater If groundwater with a designated beneficial use is The site Is located within the Orange County Management Zone of the affected by an unauthorized release, to satisfy the Santa Ana RW QCB. The areas is used for beneficial uses, including media -specific criteria for groundwater, the municipal and agricultural supply wells. Currently, the nearest contaminant plume that exceeds water quality municipal groundwater well is over 2,500 feet from the site. The objectives must be stable or decreasing in areal contaminated groundwater plume is considered stable, but high extent, and meet all of the additional The site vicinity is concentrations of TPHg still persist in shallow groundwater, characteristics of one of the classes of sites listed eligible for beneficial below. A plume that is "stable or decreasing" is a use contaminant mass that has expanded to its maximum extent: the distance from the release where attenuation exceeds migration. Class 3 a. The contaminant plume that exceeds water The current groundwater plume of TPHg and benzene is quality objectives is less than 250 feet in length. Yes approximately 100 feet in length in the longest dimension.