The Miltech Energy Services Analytical Division provides a complete line of field sampling and laboratory analyses to meet most water monitoring needs. Groundwater and Surface water samples are collected from wells, streams, ponds, springs or seeps. Samples are collected and preserved according to the analytical parameters that are to be run. Field data, such as temperature, depth, flow, field pH and field conductivity are recorded at collection. Our laboratory utilizes state of the art equipment to provide accurate analysis and fast turnaround times on such parameters as pH, Acidity, Alkalinity, Sulfate Conductivity, Iron, Manganese, Aluminum and Solids. A vast array of other organic or inorganic parameters may also be studied. Recognized industry standards such as ASTM, Standard Methods and EPA SW-846 are used for sample collection and analysis of water monitoring samples.

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During the 1990's procedures and equipment for low-flow water sampling were being developed and this method of well sampling was gaining wide acceptance by regulatory agencies. As a result, in 2002, ASTM released their Designation D6771-02 Standard Practice for Low-Flow Purging and Sampling for Wells and Devices used for Ground-Water Quality Investigations.

Using this new ASTM practice as a base, Miltech Energy Services, Inc. has developed its own equipment and procedures for low-flow purging and sampling of groundwater wells associated with solid waste and ash disposal sites. Miltech has been implementing this low-flow approach at CFB coal refuse recovery and ash disposal sites since 2003.

An adjustable volume centrifugal pump is normally used for both purging and sampling. In cases where well in-flow is very low (less than about 0.1 L/min) diaphragm pumping is used.

The 8 steps taken in the Miltech low-flow water sampling procedure are:

• Step 1 Measure the standing water level in the well
• Step 2 Lower the pump into the well to a position at approximately the mid-point of the length of the well screen.
• Step 3 Power the pump using a 12 volt battery
• Step 4 Purge the well by extracting two well volumes
• Step 5 After purging adjust pump discharge to exactly match well inflow. This is done by throttling the pump discharge to hold well level constant as indicated on the emscope probe that has been inserted into the well.
• Step 6 Pump well for a fixed period of time while holding well level fixed. Measure volume, sample and field analyze for temperature, pH and conductivity.
• Step 7 Repeat Step 6 until ASTM stabilization parameters (pH + 0.2 pH units and conductance + 3% of reading) are met over each of three consecutive readings.
• Step 8 After stabilization collect three one-liter samples for analyses as follows: One sample is treated with nitric acid to fix metals in solution. A second sample is filtered in the field and treated with nitric acid to maintain dissolved metals in solution and the third one-liter sample remains as extracted from the well. The three samples are laboratory analyzed as follows:
       Sample 1 - Metals
       Sample 2 - Dissolved Metals
       Sample 3 - pH, Acidity and Non-Metals

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