Environmental Impact Assessment is the process of identifying, predicting, evaluating and mitigating the biophysical, social, and other relevant effects of development proposals prior to major decisions being taken and commitments made.  CIZEK ENVIRONMENTAL SERVICES specializes in  the mapping and analysis of cumulative effects, which are changes to the environment that are caused by an action in combination with other past, present and future human actions.

Commissioned by the Canadian Arctic Resources Committee and the Canadian Parks and Wilderness Society, Petr Cizek conducted the very first mapping and analysis of cumulative effects in the Northwest Territories for oil/gas development in the Fort Liard area, using the GLOBIO methodology.  This project was also distributed as a wall poster to all communities in the Northwest Territories.

Afterwards, Petr Cizek mapped and analysed the induced mining development likely to result from the proposed Bathurst Inlet Port and Road in the diamond fields of the Slave Geological Province north of Yellowknife.  This report was used by the Canadian Arctic Resources Committee in their intervention in the De Beers Snap Lake Mine environmental assessment hearings.

Petr Cizek also mapped and analysed the induced exploration and development of natural gas required to supply the Mackenzie Gas Project  during its 50 year lifetime.  This project was also distributed as a wall poster to all communities in the Northwest Territories.  On behalf of the Canadian Arctic Resources Committee, Petr Cizek appeared as an expert witness before the Joint Review Panel for the environmental assessment of this project.

Petr Cizek then integrated all these maps and cumulative effects analyses into an interactive Google Earth project called "Meta-Cumulative Effects in the Northwest Territories" for the  Canadian Arctic Resources Committee.  This project was awarded an honorable mention in the 3D Visualisation Grand Challenge at the International Society for Digital Earth conference held at University of California, Berkeley in 2007.

In 2010, the Sierra Club of Canada, Prairie Chapter commissioned CIZEK ENVIRONMENTAL SERVICES to map and analyse the cumulative effects of the TOTAL Joslyn open pit tar sands project along with other existing, approved, and proposed tar sands mines.  On behalf of the Sierra Club, Petr Cizek appeared as an expert witness before the Joint Review Panel for the environmental assessment of this project.