|
• between January 13, 2005 and March 31, 2005 are included in Appendix A Certified analytical reports
<br /> with chain-of-custody documentation are included in Appendix C Analytical data were submitted to the
<br /> State Water Resources Control Board as required by AB2886 The electronic delivery receipt is attached
<br /> in Appendix C
<br /> Ozone In ection Monitoring Plan
<br /> Monitoring wells MW-3 through MW-10 are used as observation wells to monitor the performance of the
<br /> ozone infection system Monitoring wells MW-1 and MW-2 are used as background wells to evaluate and
<br /> monitor for natural geo-chemical changes in the groundwater
<br /> During the first quarter 2005, field parameters were collected on a monthly basis and select laboratory
<br /> parameters were collected on a quarterly basis During the first quarter 2005 monitoring event, all
<br /> samples were collected after purging three volumes of well casing The modified ozone injection
<br /> monitoring plan is listed below and a summary of frequency and significance of field and laboratory
<br /> parameters is presented in Table 3
<br /> Field Parameters (Monthly) pH, Dissolved Oxygen (DO), and Specific Conductivity
<br /> Laboratory Parameters (Quarterly) GRO, BTEX, five oxygenates, Chemical Oxygen Demand (COD),
<br /> Ferrous Iron, Total Iron, and Heterotrophic Plate Count
<br /> Laboratory Parameters (Annually) Total Organic Carbon (TOC), Nitrates, Sulfates, Phosphates, and Total
<br /> Dissolved Solids
<br /> Results
<br /> • Results of field and analytical parameters collected to date to evaluate and optimize the performance of
<br /> the ozone injection system are presented in Tables 4 and 5 The GRO, benzene, and MTBE
<br /> concentrations reported in all the groundwater monitoring wells during the first quarter 2005 are presented
<br /> in Figure 4 Change in DO concentrations for select observation and background monitoring wells are
<br /> presented in Figure 5 The historical GRO, benzene, MTBE, and depth to water concentration variation
<br /> over time at select monitoring wells (MW-4 through MW-8) are illustrated graphically in Figures 6 through
<br /> 10
<br /> During the first quarter 2005, GRO concentrations appeared to have both decreased and increased in the
<br /> monitoring wells since the previous monitoring event (December 9, 2004) The greatest decrease in GRO
<br /> concentrations were reported in well MW-4 (from 13,000 µg/L to 3,900 µg/L) and the greatest increase in
<br /> GRO concentrations were reported in well MW-8 (from 13,000 µglL to 27,000 µglL) GRO was also
<br /> reported in wells MW-5, MW-6, and MW-10 at concentrations of 280 µg/L, 1,800 µg/L, and 90 µg/L,
<br /> respectively GRO was not reported in wells MW-1 through MW-3, MW-7, and MW-9
<br /> During the first quarter 2005, benzene was reported in wells, MW-4, MW-8, and MW-10 Benzene
<br /> concentrations had decreased in wells MW-4 (from 2,500 µg/L to 160 µg/L) and MW-8 (from 1,400 µg/L to
<br /> 600 µg/L), since the previous sampling event (December 9, 2004) Benzene was reported at 1 10 µg/L in
<br /> well MW-10 and was not reported in wells MW-1 through MW-3, MW-5 through MW-7, and MW-9
<br /> During the first quarter 2005, MTBE concentrations appear to have decreased in wells MW-4, MW-5,
<br /> MW-6, MW-7, and MW-10, while concentrations appear to have increased in wells MW-1, MW-3, and
<br /> MW-9 MTBE concentrations had remained the same in well MW-8 (23,000 µg1L) The greatest
<br /> decrease in MTBE concentrations (from 20,000 µg/L to 4,600 µg/L) were reported in well MW-4, while the
<br /> greatest increase in MTBE concentrations (from less than 0 50 µg/L to 0 54 Vg/L) were reported in well
<br /> MW-9 MTBE was not reported in wells MW-2 and MW-7
<br /> K IBp-Arco for UR515469IQuarierly120051Arco_5469_iQ05 doc STRATUS
<br />
|