Florida Department of Environmental Protection
The Wawa Food Market #5210 site, formerly Chevron #47757, experienced a leaded gasoline discharge in the 1980s. Initial assessment activities were conducted by others through 2015.
In 2016, the property was razed to build the Wawa #5210 convenience store and gas station, burying and/or destroying all the wells previously installed onsite. Once the Wawa #5210 construction was complete, Water & Air was selected as the new FDEP consultant. The first phase of work at the site was the reinstallation of seven shallow monitoring wells and one deep well, soil sampling, and groundwater sampling. Elevated organic vapor analyzer (OVA) readings up to 265 parts per million (ppm) were recorded during well installation; however, none of the soil samples collected for laboratory analysis contained contaminant exceedances. Groundwater samples collected indicated that each of the five new intermediate zone wells (45 ft depth) contained methyl tert-butyl ether (MTBE) exceedances. Water & Air recommended the installation of additional intermediate monitoring wells to fully delineate the groundwater contamination plume on the southern and eastern edges of the property.
Water & Air’s assessment continued with the installation and sampling of new intermediate zone wells, as well as sampling 12 existing wells on both the Wawa #5210 and adjacent property. Offsite access with the adjacent property owner had to be negotiated. Six of the seven newly installed intermediate wells recorded MTBE exceedances, and Water & Air recommended installing additional delineation wells. The recommended wells were installed and sampled. The results of the sampling indicated that the groundwater contamination plume still had not been delineated on the north and northwestern edges of the property.
Delineation efforts continued with the installation of two monitoring wells on the northern edge of the property, sampling of 18 existing monitoring wells on the Wawa #5210 property, and sampling of five monitoring wells on the adjacent property to the east. Laboratory results for monitoring well MW-95B, installed on the northwest corner of the Wawa store property, did not show exceedances and bound the contamination in that area for that aquifer zone. The well installed in the northeast portion of the parking area, MW-94B, recorded an MTBE exceedance. Continued assessment included the installation of a monitoring well on the adjacent north property, sampling of 17 existing monitoring wells on the Wawa #5210 property, sampling of four monitoring wells on the west adjacent property, and the new well. The new offsite well to the east continued to show GCTL exceedances.
Water & Air has proposed the installation of two final wells to complete the dissolved plume delineation. As the only petroleum constituent that exhibits exceedances is MTBE, the future remedial efforts at this site will be preparation of a Remedial Action Plan for the design of a treatment plan to clean up the large dissolve plume that extends over three properties.