Casey Resources, Inc. (CRI) is staffed with a Hydrogeologist who is qualified to evaluate and discuss recommendations from surface impoundment investigations with the Environmental Engineer. Surface impoundments serve a variety of beneficial uses in a number of industrial processes. Industrial facilities that produce wastewaters often use surface impoundments to perform necessary wastewater treatment prior to discharge into surface waters. In other cases, industrial facilities may need to control wastewater flows and use surface impoundments for storing excess wastewater. In still other cases, industrial facilities may use surface impoundments to manage their excess wastewaters through evaporation or seepage into the ground.
Surface impoundments are used by many industrial sectors, such as manufacturing, bulk petroleum storage, air and truck transportation, waste management, and national security. The wastewaters managed in these surface impoundments are primarily from manufacturing and washing processes and certain contaminated stormwaters. More than half of the impoundments with chemical constituents or pH of interest are in the chemical, concrete, paper, and petroleum industries.
Industrial impoundments vary greatly in size, from less than a quarter of a hectare (1/3 of an acre) to several hundred hectares. The larger impoundments provide the bulk of the total national industrial impoundment capacity. On a volume basis, the paper and allied products sector manages roughly two-thirds of the total quantity of wastewater; more waste is in impoundments than all of the other industry categories combined.
Industrial impoundments frequently use management techniques that increase the potential for chemical releases and frequently are found in environmental settings that increase the potential for impacts to humans or ecosystems in the event of a chemical release. In this study, the Environmental Protection Agency (EPA) found that most industrial impoundments are located only a few meters above groundwater and that, in most cases, shallow groundwater discharges to a nearby surface water body. More than half of the impoundments do not have liner systems to prevent the release of wastes to soil or groundwater. In addition, about 20 percent of impoundments are located within 150 meters of a fishable water body, so migration through the subsurface to the nearby surface water is possible. Finally, while aeration can have certain benefits, it also increases volatilization and the potential for airborne contaminant migration. The EPA found that about 45 percent of the total wastewater quantity managed in impoundments is aerated.
After evaluating impoundment settings and operations and confirming there was potential for releases, CRI would recommend to the client to go a step further and conducted a risk assessment to examine the degree to which the chemicals found in impoundments were likely to be released from impoundments, and ultimately expose people to harmful chemicals.