Success Stories
4395 Rocklin Rd. – Rocklin
In 1995 a 250-gallon waste oil underground storage tank was removed from the site. Soil samples collected from beneath the tank were reported to contain detectable concentrations of total petroleum hydrocarbons as gasoline (TPHg) and diesel (TPHd), total oil and grease (TOG), the volatile aromatic compounds of benzene, toluene, ethylbenzene, and total xylenes (BTEX), naphthalene, and 2-methynaphthalene. In the following years, soil borings were advanced and samples were taken to determine the extent of the contamination on the site. Up until 2005, several different firms were contracted to perform remedial services at the site, including implementing dual phase extraction (DPE) and air sparging (AS) systems.
In 2005, E2C was contracted to perform environmental services at the site. Shortly thereafter, E2C directed the removal of three 6,000 gallon underground storage tanks from the site. In March 2006, E2C directed the installation of six air sparge wells at the Site and in June, July, and early August, 2006, E2C completed construction of the remedial compound, completed the plumbing of DPE and AS wells to the remediation compound, completed construction of a treated-water infiltration gallery, and mobilized remedial system components to the Site.
Quarterly groundwater monitoring commenced in March 1997 and continued through 2009, when a reduced monitoring schedule was approved by the CRWQCB and implemented by E2C. In the Third Quarter 2010, the reduced monitoring schedule was modified to include quarterly, semi-annual, and annual groundwater sampling. This modified monitoring schedule was approved by the CRWQCB in November 2010.
First Quarter 2014 groundwater monitoring data indicated very small BTEX, TPHg, MtBE, and TBA groundwater plumes. Based on groundwater monitoring data from the First Quarter 2015 monitoring report, E2C recommended suspending groundwater monitoring activities, and to commence site closure activities. A letter from the Central Valley Regional Water Quality Control Board dated December 19, 2014 confirmed that no further action would be required at the site.