Ground and groundwater monitoring in inhabited areas near a brownfield site
The Pilot Area delivered by the City of Bydgoszcz is focusing on the area of the "Zachem” Chemical Plant, located in the South-Eastern part of the city
- Characteristics of the brownfield:
The post-industrial area of the former Zachem Chemical Plant in Bydgoszcz has a surface of approximately 2,00 h. The Zachem factory, from the Sixties until 2013, was the largest producer of organic chemicals in Poland.
- Main issues/problems:
- Highly toxic substances get into the soil and groundwater causing a strong contamination
- It is difficult to reliably determine the current state of environmental pollution due to the
defective existing monitoring system
- The long-term emission of pollutants to the environment, as well as the lack of actions
preventing their migration, have caused that highly toxic, carcinogenic and mutagenic
pollutants move outside the premises of Zakłady Chemiczne "Zachem" to inhabited areas
(Łęgnowo and Plątnowo settlements), causing health hazards to resident
- Needs and Goals:
The Pilot Action aims at assessing the environmental risk associated with the contamination brought on by the former chemical factory as well as its impact on neighbouring area.
- Activities, achievements and results:
The City of Bydgoszcz completed its investigation on the status of the ground and groundwater contamination on the site of the former chemical factory and on the neighboring area. A report assessing the environmental conditions is now available.
An inventory of the existing piezometers (observation holes) was made, 15 piezometers were drilled and soil and water samples were chemically tested. In each of the piezometers the first aquifer is contaminated by toxic organic and inorganic compounds.
The city prepared conceptual site model to define the groundwater flow and migration of contaminants to the inhabited area. As a result of the simulation, the time of groundwater flow was calculated from 19 pollution outbreaks to inhabited area. Numerical studies on pollutants were documented on 60 graphical annexes in time steps +25 years for sulphates and chlorides and +50 years for organic compounds. The analyses show that the area of contaminated will gradually expand towards the inhabited area of Łęgnowo. Based on previous studies it was possible to draft guidelines and recommendations for future monitoring operations that includes proposals for the designation of areas which should be covered by groundwater monitoring, the type and quantity of samples, methodology, scope of analytical tests, frequency of sampling, presentation of monitoring results, estimation of costs and time plan. The purpose of the planned monitoring will be the ongoing observation of the inflow of groundwater pollution migrating from former "Zachem" towards the Łęgnowo - Wieś estate, in the context of the impact assessment on the residents and deterioration of the quality of the soil and water environment.
At the same time c.a. 500 ground samples were collected from inhabited area in order to complement the data for risk analysis. Health risk analysis aimed at analyzing the potential negative health effects that may occur as a result of exposure to harmful substances present in the environmental media of soil in residential areas.
- Involvement of stakeholders:
The most important local stakeholders involved in the Pilot Action are: RDOŚ Regional Directorate of Environmental Protection, WIOŚ Regional Inspectorate for Environmental Protection, SANEPID District Sanitary and Epidemiological Station, MWIK Municipal Waterworks, AGH University, Inhabitants of Łęgnowo.