Operational monitoring groundwater

Cherkauer (1980) monitored groundwater near a fly ash site, operating 8 years for the Port Washington Power Plant in southeastern Wisconsin, USA. The maps in Fig. 16.16 show the potentiometric surface contours and direction of flow, TDS, S04, Ca, and HC03, along with the positions of the monitoring piezometers. The ash leachate contained various metals that were not observed in the monitoring wells, except some iron. 

Operational monitoring is relevant to groundwater bodies at risk, and the monitoring of parameters in Block 1 plus additional parameters indicative of the risks to the groundwater body are obligatory. 

Monitoring. Groundwater and soil sample monitoring is required for the following parameters before a landfill (or treatment) site is opened, during the site s operation, and for some time after its closure. 

Unit 1, Nebraska - 20 ppb. Post-operational ISL mining caused [U] to be orders of magnitude larger in monitoring groundwater wells. 

RCRA s TSDF standards also include provisions to protect groundwater and air resources from hazardous waste contamination. RCRA requires owners and operators of land-based units (i.e., land treatment units, landfills, surface impoundments, and waste piles) to monitor the groundwater below their TSDF for possible contamination, and clean up any discovered contamination. 

Approximately 1400 samples were collected from predominantly farm wells and bores, although dewatering bores and groundwater monitoring bores were also sampled. Water was collected from the outflow pipe when the bore or well was operational, or bailed using a flow-though system with one-way valves. Additional samples were added to the assessment from previous work to enhance the study around key mineralised sites such as... 

After start-up, the system should be checked at least weekly, with some observations, notably in the early phases, requiring daily monitoring. Information such as ground-water levels, extraction and injection flow rates, groundwater electron acceptor concentrations, nutrient concentrations, pH, and conductivity should be recorded at least on a weekly basis. Complete records of rates, concentrations, electrical usage, and other operational data can be invaluable when evaluating operational efficiency or documenting unit costs. 

Additional design, operating, and monitoring requirements may be necessary for facilities managing dioxin wastes in order to reduce the possibility of migration of these wastes to groundwater, surface water, or air so as to protect human health and the environment. 

The vendor supplied an unspecified case study that compared the costs of an existing pump-and-treat system with a pump-and-treat system that had been retrofitted to accommodate an FE ACTIVE. The projected life-cycle cost (adjusted for an inflation rate of 4% and a rate of interest of 5%) of the existing pump-and-treat system was calculated to be 3,930,000 (1996 dollars). The life-cycle cost (adjusted for a 4% inflation rate and a 5% interest rate) of the FE ACTIVE retrofit system was calculated at 945,000 (1996 dollars). Both estimates included capital costs, operation and maintenance expenses, and the cost of groundwater monitoring. Similarly, had the FE ACTIVE system been installed initially, its life-cycle cost would be 1,630,000 (1996 doUars). 

In 1991, Roy cited costs at a Central Lake, Michigan, 1-acre site with an initial trichloroethylene (TCE) level of 500 ppb at 160,000. The groundwater phase of the project cost 100,000, with annual operating costs of between 15,000 and 20,000. Initial investment at a site in the Netherlands was estimated at 80,000. Monitoring costs were lower for the Netherlands site due to less stringent requirements (D12730A). 

The NMED approved an operation and maintenance plan in November 1995, and DBS A started operation of the SVE system in early December 1995. On April 29, 1996, monitor well MW-9 was incorporated into the SVE network to provide further control of the groundwater plume (Fig. 6). 

The extension of SVE techniques to low-permeability soils was based on monitoring the vapor recovery rate and using the results of mini-pilot tests to adjust SVE system operation. The periodic mini-pilot tests provided information from individual SVE wells, including air flow, well vacuum, and hydrocarbon concentration in the extracted vapors, that was used to balance the flows. Wells with low hydrocarbon concentrations were shut off to focus remedial efforts on the most contaminated locations, and during some periods, wells with high flows were shut off to allow a more balanced flow from low flow wells or to provide hydraulic control along the periphery of the perched groundwater contaminant plume. 

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