Laserfiche WebLink
Aj Groundwater Monitoring Well Installation and Ozone Microsparge System Installation and Startup Report— <br /> ConocoPhillips(76)Service Station No. 11195,Lathrop,California <br /> May 20,2003 <br /> 5.4 Tnterim Remedial Action <br /> As an interim remedial action measure, GR installed a K-V Associates, Inc. C-SpargJ"' ozone <br /> microsparging system. Ozone microsparging is a process where ozone in air is introduced into the <br /> groundwater at low flow rates (2-6 cubic feet per minute) through specially designed spargers to <br /> create "microbubbles." As these microbubbles rise within the column of water, dissolved Volatile <br /> Organic Compounds (VOCs) are rapidly oxidized. <br /> The ozone microsparge panel was installed in the southwest comer of the site as shown on drawing <br /> number G2. The panel includes an ozone generator, air compressor, and a programmable <br /> timer/controller. Sparge points are connected to the panel by 318" diameter High Density <br /> Polyethylene (HDPE) tubing. Each sparge point has a dedicated line. The tubing was run through <br /> Schedule 80 PVC conveyance piping for added protection. The process flow diagram is presented <br /> on Figure 4. <br /> 5.5 OzoneMicrosparge System Stat1up <br /> The system was placed into operation during the last week of December, 2002. The system cycles <br /> ozone/air injection between the fifteen sparge points. The schedule is currently set to cycle through <br /> each point 16 times per day, for between. 5 and 15 minutes per point,per cycle. The schedule can be <br /> varied as part of the system evaluation process. <br /> 5.6 Groundwater Sampling <br /> z v <br /> Groundwater samples will be collected from selected monitoring wells once a month and submitted <br /> to a California certified hazardous material testing laboratory. The samples will be analyzed for <br /> TPHg, BTEX, and MtBE by EPA Method 8260B. Results of the monthly groundwater sampling <br /> will be summarized in a semi-annual system status report. <br /> 5.7 Ozone Microsparge System Operation and Maintenance and Reporting <br /> System operation and maintenance (O&M) will be performed bi-weekly for the first month, then <br /> monthly. A system status report, presenting the results of the sampling program, will be issued <br /> after the first six months of operation. At that time, the effectiveness of the system will be <br /> evaluated. The routine groundwater monitoring and sampling data will be utilized to prepare the <br /> system evaluation. <br /> 140193.14-2 7 <br />