DoAct CORE

Doranova has started a remediation pilot in 2018 for soil and groundwater at the Hanasaari power plant premises (Helsinki, Finland). The pilot is conducted with the DoAct® CORE equipment. The contract is implemented together with Golder Associates Oy which is responsible for the environmental technology supervision, sampling, and reporting to the client. The aim of the pilot remediation is to test and verify the applicability of the DoAct® CORE equipment and related technologies at the site. The main contaminants in Hanasaari include naphthalene and BTEX-compounds.

The pilot remediation consists of the following technologies:

1. In the first phase, the biological degradation of the contaminants soluble to groundwater is enhanced by adding the biological degradation limiting substances to the saturated zone. The degradation is enhanced with new innovative methods, such as the injection of supersaturated water. This technique has never before been used in Finland.

2. BAfter biological remediation, the residual contaminant concentrations are reduced by injecting activated carbon product to the groundwater. The injections are performed with Doranova’s DoAct® DIRECT direct push injection equipment.

3. The third examined method is the controlling of soil pore gas. This prevents the migration of the volatile compounds from the soil and groundwater to the indoor air of nearby buildings.

The more detailed results from the pilot remediation are completed during 2019. A time frame of several years has been reserved for the remediation of the whole Hanasaari area.

Doranova has remediated Vapo Oy’s Pursiala sawmill’s soil and groundwater by using enhanced biological attenuation (ENA) since 2016. The project is supervised by FCG Suunnittelu ja Tekniikka Oy and Sitowise Oy. The biologically enhanced attenuation is executed by using Doranova’s modular DoAct^® CORE remediation unit that enables extraction of groundwater, treating it and returning it back into the soil. DoAct® CORE also makes it possible to use oxygen releasing compounds to optimize the oxygen concentration in the groundwater. Added oxygen enhances aerobic microbial activity and the breakdown of the contaminants. The remediation with ENA technique has been a success and the results indicate that there is no need for the before planned chemical oxidation. In 2018 it was decided to boost the remediation with direct injections using Doranova’s DoAct^® DIRECT equipment.

The idea behind enhanced biological attenuation is to create optimized conditions for reproduction and population increase for the microbes breaking down chlorophenols. The growth of the microbial population can be boosted by injecting nutrients and oxygen into the soil. Doranova’s DoAct^® CORE equipment is fully automatized and remotely controllable. The equipment includes, among other things, modules for groundwater extraction, treatment of suspended material, aeration with ejectors and filtration with activated carbon.