When groundwater testing reveals contaminants at your construction or infrastructure repair site, formulate a plan to remove them using a temporary water treatment solution. This sounds simple enough on the surface. Why, then, do other groundwater contaminants sometimes emerge unexpectedly, adding costs and delaying project timelines?

It's tempting to blame inaccurate test results or inadequate sampling, but most often, the real culprit is Mother Nature.

3 reasons new groundwater contaminants emerge

Water is dynamic. It can change in composition from minute to minute due to a host of factors. A good temporary water treatment partner will know this and explain the risks upfront. Here are three reasons new contaminants emerge.

Rainfall and snowmelt

Rainfall, snowmelt and other weather events can change the chemical composition of water. For example, storm runoff can cause oils, decaying organic matter, fertilizers and other chemicals and even heavy metals to seep into the water, potentially changing the groundwater remediation method needed.

Contaminant striation

What you find at the top of a water source isn’t necessarily what you find at the bottom. This is especially true with stagnant water. Heavier, denser and/or less volatile chemicals tend to sink. As you drain the water, they may eventually show up as “new” contaminants.

Groundwater migration

Groundwater knows no borders, and contaminants travel with it. If your dewatering project spans several days or weeks, the water you pull in toward the end of the project may have traveled a significant distance. If that water came from a different environment — perhaps it was near a farm or industrial activity, for example — it could contain different chemicals from those found in the water you sampled.

How to handle new groundwater contaminants

If unexpected contaminants emerge, reach out your supplier partner right away. A supplier can help design a solution that best fits your new challenges and budget.

A supplier that anticipates changes in contaminant levels and types of contaminants may factor these changes into the temporary water treatment solution right from the start. For example,United Rentals offers modular units that can be moved and rearranged in response to changing circumstances. For example, modular units can be arranged in an “L” or “U” shape. Piping can be run over roadways or around structures in some cases.

The supplier may also suggest spending a little more money on the treatment plan upfront so you can be ready to handle new contaminants faster and avoid the costs of delays.

The moral of the story: Expect “new” contaminants and new levels of contaminants, and factor them into your timeline and costs rather than finding yourself behind schedule and over budget. Work with a supplier that can assist with preparing a temporary water treatment solution.

Contact the United Rentals Fluid Solutions group for help with all your temporary water treatment and filtration needs.