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Soil Investiga•and Background Groundwater Monitorin*ell Installation Workplan
<br /> January 17,2007
<br /> C A M B R I A
<br /> Soil Sample Analyses: Select soil samples will be analyzed for organic content by ASTM D2974,
<br /> sieve and hydrometer by ASTM D422; effective porosity, total porosity, moisture content, dry
<br /> density, and specific gravity by ASTM D2325 modified; soil pH by ASTM G51; and cation
<br /> exchange capacity (CEC) by Environmental Protection Agency (EPA) method 9081. In addition,
<br /> select soil samples will be analyzed for oil and grease by EPA method 413.1;total mercury by EPA
<br /> method 7470;aluminum,cadmium,calcium,copper,iron,lead,magnesium,manganese,potassium,
<br /> sodium,thallium,and zinc by EPA method 6010;and sulfate,orthophosphate as phosphate,chloride,
<br /> nitrate as nitrogen, and nitrite as nitrogen by EPA method 300.0.
<br /> Well Elevation Survey:After well installation,top-of-casing to 0.01 feet and horizontal and vertical
<br /> ® coordinates will be surveyed by a licensed land surveyor provided by the District
<br /> Well Development and Groundwater Sampling:Development of wells MW-1 through MW-3 will
<br /> occur at least 48-hours after well construction. Cambria's standard operating procedures for
<br /> groundwater monitoring,sampling,and well development are included as Attachment B.We propose
<br /> to conduct up to four consecutive monthly groundwater sampling events to gather initial groundwater
<br /> data. After the four initial groundwater sampling events are completed the wells will be sampled
<br /> quarterly upon operation of the infiltration/evaporation pond.
<br /> Groundwater Sample Analyses: Groundwater at the site will be field tested for pH,oxidation and
<br /> reduction potential(ORP),electrical conductivity,temperature,and dissolved oxygen. In addition,
<br /> groundwater samples will be analyzed for oil and grease by EPA method 413.1;aluminum,cadmium,
<br /> calcium, copper (total and dissolved), iron, lead, magnesium, manganese, potassium, sodium,
<br /> thallium,and zinc by EPA method 6010;total mercury by EPA method 7470;hardness(as CaCO3)
<br /> by EPA method 130.2;total dissolved solids(TDS)by EPA method 160.1;ammonia by EPA method
<br /> 350.2;and sulfate,orthophosphate as phosphate,chloride,fluoride,bromide,nitrate as nitrogen,and
<br /> nitrite as nitrogen by EPA method 300.0. Selected parameters will be analyzed during the quarterly
<br /> monitoring events once the infiltration/evaporation pond becomes operational.
<br /> Slug Test: Slug tests are a means by which a single well can be utilized to estimate the horizontal
<br /> hydraulic conductivity of saturated subsurface soil. Slug tests are generally used as a low cost
<br /> substitute for more expensive aquifer tests. Although slug tests are widely used and generally
<br /> accepted, it should be remembered that slug tests yield only local values of horizontal hydraulic
<br /> conductivity(within a close proximity to the well) (Bouwer, H., 1978).A slug test is a rate-of-rise
<br /> test where the hydraulic conductivity is determined from the rate of rise of the water level in a well
<br /> after this level was abruptly lowered by the sudden change of a known volume of water from the
<br /> well.Cambria proposes conducting slug tests in all three monitoring wells to get a range of hydraulic
<br /> conductivities at the site. We will use a slug of known volume and insert it in the well. The water
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