ARCHIVED REPORTS_SECOND SEMIANNUAL AND 2014 ANNUAL GROUNDWATER MONITORING REPORT

Home Browse Search

2.RESULTS FOR SECOND SEMIANNUAL PERIOD 2014 were not detected in wells M-1 and M-8 in previously collected samples (petroleum hydrocarbons were not present above the laboratory reporting limits in these wells). Compounds detected in shallow groundwater during the second semiannual period 2014 include the following: • TPHg was detected in shallow groundwater at wells N-7, N-17, and RW-1. Reported concentrations of TPHg in these wells ranged from 3.7 milligrams per liter (mg/L) at wells N-7 and N-17 to 8.7 mg/L at well RW-1. • TPHd was detected in shallow groundwater at wells N-7,N-17, and RW-1. Reported concentrations of TPHd in these wells ranged from 0.70 Z mg/L at well RW-1 to 8.6 Z mg/L for the duplicate sample at well N-7. • BTEX compounds were detected in shallow groundwater at wells N-7, N-15,N-16,N-17, 0-1,and RW-1. Reported concentrations of benzene in these wells ranged from 8.5 micrograms per liter (µg/L) at well N-17 to 2,400µg/L at well RW-1. Deeper Groundwater No TPHg,TPHd,or BTEX compounds were detected in samples from deeper well N-24. This is consistent with data reported during previous sampling events. 2.2 Status of Remediation and Other Completed Activities This section presents the status of remediation and other completed activities for the second semiannual period 2014(April through September 2014). ' 2.2.1 Remediation Activities The following remediation activities were performed. ' • Phytoremediation. Maintained the phytoremediation system as described in the Cleanup Plan Using Phytoremediation for the Source Area (CH2M HILL,2004). • Monitored Natural Attenuation. Continued semiannual groundwater monitoring and reporting in accordance with MRP No. R5-2007-0831. Groundwater concentrations for TPHg,TPHd, and BTEX constituents continue to be stable to decreasing on a sitewide and seasonal basis. 2.2.2 Other Completed Semiannual Activities ' The following additional activities were completed. Wildlife Habitat Council Certification SFPP continued implementing the Wildlife Habitat Management Plan submitted with the initial certification application to the Wildlife Habitat Council (WHC) (August 31,2007) as updated with the third recertification application(June 28,2013). The recertification period is for 3 years. The primary activities performed during the semiannual period included maintaining the habitat improvements installed as part of the Wildlife Habitat ' Management Plan. ' ES101214202053SCO 2-5