It’s best to avoid contaminating soil and water in the first place by handling wastewater and similar contaminants properly from the beginning. However, sometimes lax standards or accidents lead to serious contamination that’s hard to remove. Remediation of a contaminated site is generally guided by the EPA but funded by the landowner or former business owner. Whether you’re dealing with abandoned mining sites, fuel storage facilities, or chemical plants that operated for years with improper containment, remediation can cost millions of dollars and take decades. Many contaminated sites feature standing water, either from underground storage tanks or accumulated storm water, that is high in heavy metals, toxic chemicals, or bacteria-laden organic material. Processing this wastewater in an on-site evaporation pond is often the first step to cleaning up a brownfield or EPA superfund site.
Temporary to Long-Term Installation
Evaporation ponds installed at contaminated sites can range in intended use from temporary installations, for just a few months of use, to permanent structures planned to remain in place for the foreseeable future. In the most contaminated sites, remediation can stretch out over a period of decades as bacteria slowly break down compounds in the soil. Evaporating millions of gallons of wastewater doesn’t take nearly as long, but many sites continue to produce new sources of contaminated water until remediation is complete.
Don’t assume you’re giving up any valuable future use of the contaminated site just by adding evaporation ponds during remediation. Since these ponds are kept as shallow as possible to speed evaporation through wind and sun exposure, they’re easy to fill back in after remediation ends. Kennecott, a copper mining facility outside of Salt Lake City, UT, had to remediate multiple superfund sites involving dangerously high levels of heavy metals that had leached into the sludge and soil around the processing sites. The southern site of the Kennecott project involved evaporation ponds that were filled in and turned into over 13,000 homes and 9 million square feet of commercial space.
Capturing Valuable Minerals and Metals
If there’s any useful material left in the sludge or water gathering at a contaminated site, it’s best recaptured through the use of an evaporation pond. Reducing the volume of water creates a condensed sludge or solid cake material is easy to sift and treat as needed to reclaim valuable minerals and metals. This is easier to do at sites with a single form of primary contamination rather than a highly mixed chemical blend.
Sticking to Remediation Timelines
Even when the EPA’s plans involve decades of wastewater evaporation and soil treatment, it can be tricky to stay on a timeline. Falling behind on remediation goals can cost millions of dollars in fines, extend the cost of reclamation, and reduce support from the local community. Evaporation ponds keep the process flowing smoothly so that all milestones are met in the proper time. This is because it’s relatively easy to measure and estimate the evaporation rate at a particular site, making it possible to predict how long it will take to reduce water by a specific volume for further processing. Other leachate treatments can vary more in their timeframes, making it harder to stay on an EPA supplied plan.
Evaporation ponds may be the original reason a site became contaminated if it wasn’t lined properly or became damaged over time. Installing new ponds that are properly lined with a quality geomembrane gives you the perfect space for transferring material out of leaking or damaged, existing structures. If the site does not have the evaporation or storage ponds it needed, it’s never too late in the remediation process to install them.