Content
Management Plan
Management plan
Although the group of stakeholders (GOS), have not made the decision on the selection of the final risk management scenario (RMS) from the three preferred scenarios, scenario S1 is currently being implemented. However, implementation of two other scenarios: S2 and S3 in future is not excluded. The final decision was not taken, because of the uncertainties in boundary conditions. For the preferred scenarios three organizational schemes were outlined.
Scenario S1 - controlled NA (see: Risk management scenarios -> potential scenarios).
There is a formal decision to include the established risk management zone (RMZ) in the watershed management plan realized by the Regional Water Management Board, which is responsible for carrying out permanent assessment, verification and management of the risks within the RMZ.
This scenario is realized within the existing organizational structure based on the legal obligations of the local and regional administration and the megasite management organization (the liquidator of chemical plant).
Scenario S2 - active groundwater remediation. (see: Risk management scenarios -> potential scenarios).
A new organization unit within the local and regional administration should be established to take the responsibility for implementing this scenario after the chemical plant liquidation program is completed. However, the megasite owner can make a contract with a private company to implement the scenario.
Scenario S3 - engineered NA. (see: Risk management scenarios -> potential scenarios).
Successful implementation of this scenario requires engagement of different stakeholders (local and regional administration, industry). New management structure can be established to intensify the processes of the megasite redevelopment. In the organization scheme for this scenario a public-private partnership (PPP) model may be preferred. Local and regional administration may have a leading position in implementation of this scheme. The organizational pattern should reflect the two processes: remediation and redevelopment of the megasite at the same time.
Monitoring Program
Monitoring program
In the case of the Tarnowskie Góry megasite the monitoring program should include groundwater quality, especially of the Triassic aquifers, as well as the performance of the controlled landfill and the secondary sources of contamination (i.e. quaternary sediments).
It is proposed that after the year 2005 the monitoring should focus mainly on the Triassic aquifer with the objective of tracing migration of potential contaminants from the area of dumping sites and quaternary sediments to the operating groundwater intakes. The monitoring of the Quaternary water-bearing horizons within the area of former dumping sites should be significantly reduced.
Analysis of the groundwater quality monitoring results, modeling and the representativeness of the monitoring points of the Triassic aquifer shows that -in order to obtain a more reliable assessment of the dynamics and range of the plume movement within Triassic water-bearing horizons- it is necessary to modify significantly the monitoring program conducted so far. A new organization of a monitoring system for the megasite, i.e. locations of monitoring points, is presented in the figure below.
It is necessary to limit the inspections of the source area (the former dumping sites and their nearest vicinity) in favour of the pathway area (dominant groundwater flow directions). It is also necessary to verify the sampling protocol, i.e. sampling technique, frequency and parameters to be measured (number and range).
A reliable assessment of contaminants' spatial distribution and migration rate in multi-layer aquifers needs an appropriately designed and developed observation network with the observation wells (piezometer), enabling sectional sampling of water at different depths. Sectional sampling can be done either by a single well screened at different depths, or by a group of wells each screened at a different depth. In the first case a well can capture different sections of the same water-bearing horizon of large thickness, or separate aquifers isolated from each other by impermeable deposits.
It should be pointed out that for the suggested modifications of the monitoring program no new boreholes need to be drilled but existing wells can be used.
Review Process
Review process
All RMS considered for the Tarnowskie Góry megasite are based on the removal of hazardous waste and depositing them in a controlled landfill. According to the GOS the decision on the final RMS can only take place after completion of the chemical plant liquidation program. This decision should be made on the base of the revised boundary conditions. Then, it becomes possible to continue with the IMS steps including further detailing of the chosen RMS (see: Risk management scenarios -> Final scenarios).
Then, the appropriate plans of the review process can be developed.
At this point of IMS implementation for the Tarnowskie Góry megasite, only the review process for monitoring program could be proposed. Monitoring should be continuously revised and modified depending on the changes in the plume movement within the aquifers and boundary conditions.
