Evonik remediates groundwater in Hanau neighborhood in award-winning project  

Hanau, Germany. Evonik is remediating groundwater contaminated with volatile organic compounds (VOCs) at the Pioneer Park urban development site in Hanau. Once a military barracks, the area is undergoing transformation into a modern neighborhood set to house 5,000 residents. The project is utilizing Evonik’s product EHC® Reagent, environmental consulting from AECOM, and field technology from Sensatec to remediate two contaminated areas. On 16 May, the partners were awarded the bronze medal in the category “Especially Sustainable” at the Brownfield Award® 2024.

The 50-hectare site has been under successive development into an urban living space since 2018. In 2020, two areas covering 11,000 square meters showed impermissible levels of VOCs in the groundwater, primarily caused by dry cleaning activities at the former barracks. In consultation with global infrastructure consultancy AECOM, the project owner LEG Hessen-Hanau – a BIG BAU Group company – together with the city of Hanau and local regulators selected Evonik’s EHC® Reagent to resolve the issue.

EHC® Reagent is specially formulated to degrade VOCs – substances that are notoriously difficult to destroy. It combines controlled-release organic carbon with micronized zero valent iron (ZVI) to trigger chemical and microbiological degradation. From 2020 to 2023, Evonik worked together with field technology expert Sensatec to inject EHC® Reagent into the subsoil under high pressure. Monitoring in March 2024 demonstrated that this “in situ chemical reduction” (ISCR) is on track to degrade the VOCs down to levels significantly below permissible limits.

“The advantage of ISCR is that it saves costs, energy, and time compared with other remediation methods,” said Mike Mueller, EMEA Business Manager for  Soil & Groundwater Remediation at Evonik’s Active Oxygens business line. “There is no need to pump out the groundwater in order to treat it. ISCR is thus associated with significantly lower CO₂ emissions than alternative measures.”

Hanau Mayor Claus Kaminsky stated: “It is important to us that the soil and groundwater quality in Pioneer Park is completely within acceptable parameters. Thanks to the companies involved and Evonik’s reagent, we are on our way. The fact that Evonik, a company from the immediate vicinity, had the right solution ready makes it all the better. An excellent example of community at work.”

In fact, the remediation work at Pioneer Park was particularly recognized at the German Brownfield Award® 2024 on 16 May, taking the bronze medal in the “Especially Sustainable” category. The project was honored for its sustainable approach and contribution to local social and economic development.

EHC® Reagent is sustainably produced using recycled raw materials. It contains nutrients to activate biological decomposition which are derived from a grain-milling by-product, and the ZVI is sourced from scrap iron. Like all of Evonik’s soil and groundwater remediation portfolio, EHC® Reagent is non-toxic and, after breaking down contaminants into harmless molecules, fully degrades itself.

Read the full story of the Pioneer Park remediation project on the Evonik Active Oxygens website.

Learn more about Evonik’s Soil & Groundwater Remediation business at evonik.com/remediation.