Laserfiche WebLink
4 .aeofagicaf?echnics 7=. � Page 5 <br /> &B Equipment <br /> Additional Site Characterization WP Addendum <br /> Project No.336.2 <br /> April 7, 1997 <br /> grade with the surrounding surface. Several of the soil samples from this borehole would <br /> �- then be submitted for BTEX and TPH-Gas analysis. <br /> 4.0 SOIL AND GROUNDWATER SAMPLE ANALYSIS <br /> 4.1 Modified Groundwater Monitoring Well Sampling Procedure <br /> In addition to monitoring water quality parameters (i.e. temperature, conductivity, and pH) <br /> we propose to begin gathering data which will offer information regarding the plume's <br /> stability. <br /> Comparing upgradient information with that from the inside of the plume can offer evidence <br /> that an apparent reduction in gasoline range petroleum hydrocarbon concentration in the <br /> water is not completely due to sorption, diffusion, or advection but rather the system is taking <br /> care of itself. <br /> Some of the specific parameters can be monitored relatively inexpensively in the field and <br /> have the potential for providing valuable and comparative information regarding intrinsic <br /> bioremediation in the groundwater. <br /> • Dissolved Oxygen - useful in determining if there is enough oxygen present to support <br /> aerobic degradation. <br /> • Oxidation-Reduction Potential - useful in determining the state (oxidizing or reducing <br /> conditions) of the aquifer. <br /> Alkalinity - can be a useful indicator of bioactivity. <br /> Nitrate (NO,) - can be a useful indicator of bioactivity. <br /> • Sulfate (SO,) - can be a useful indicator of anaerobic degradation of fuel compounds. <br /> �- • Ferrous Iron (Fe2+) - can be a useful indicator of anaerobic degradation of fuel <br /> compounds. <br /> ` It is imperative that the D.O. and ORP parameters be evaluated using stabilized groundwater <br /> pumping techniques and a flow cell. <br /> _ Although field assay kits (colorimetric) are available, because of the data accuracy <br /> i' requirements, we recommend that the electron acceptor data (NO„ SO„ Fee') be tested by <br /> laboratory analyses (NO„ by EPA 353.2 S03, by EPA 375.4 & Fe2+by EPA 200.7). <br /> .. We recommend that groundwater samples to be tested for NO,, & SO, be preserved with <br /> HNO3,and the plastic sample container completely filled avoiding headspace, and then placed <br /> in a chilled cooler as usual. <br /> `r We recommend that groundwater samples to be tested for Fel+ be filtered immediately <br /> through an inline 0.45µm filter, preserved with HNO,, and the plastic sample container <br /> completely filled avoiding headspace, and then placed in a chilled cooler as usual. <br /> 4.2 Soil and Groundwater Analyses <br /> �. Soil and groundwater samples will be submitted to Sherwood Laboratories of Hilmar (State <br /> Certified Laboratory #1400) following chain of custody protocol. <br /> V <br /> V <br />