Monitoring is a cornerstone of EIA implementation and follow up. Other components are dependent on the scope and type of monitoring information that is provided. The primary aim of monitoring is to provide information that will aid impact management, and, secondarily, to achieve a better understanding of cause-effect relationships and to improve EIA prediction and mitigation methods. Both the immediate and long-term benefits from undertaking monitoring as part of EIA are widely recognised, although not always realised.
Monitoring is used to:
- establish baseline trends and conditions;
- measure the impacts that occur during project construction and operation;
- check their compliance with agreed conditions and standards;
- facilitate impact management, e.g. by warning of unanticipated impacts; and
- determine the accuracy of impact predictions and the effectiveness of mitigation measures.
A sound baseline is a critical reference point for the conduct of effects monitoring. In turn, effects monitoring establishes the basis for corrective action when actual impacts are unanticipated or worse than predicted. Compliance monitoring, carried out through repetitive or periodic measurement, also can be used for this purpose. This may suffice as a safety net for certain projects, for example, where the mitigation measures are well tried and known to be effective. However, compliance monitoring will trigger impact management only if regulatory standards or specified conditions are exceeded and, on its own, may be insufficient for large-scale, complex projects.
By themselves, compliance and effects monitoring permit only reactive impact management, since they detect violations or adverse changes after the fact. In this context, it is important to tie the results of both types of monitoring to predetermined actions (or emergency responses), which are triggered on a threshold basis. A more proactive, adaptive approach to impact management can be instituted by combining compliance or effects monitoring with supervision or regular inspection of site clearance, construction and mitigation activities. The use of the precautionary principle can facilitate early warning of emerging problems.
The collection of monitoring data is expensive. It needs to be targeted at the information necessary to manage the impacts that are significant or review the aspects of EIA practice that are of particular importance. These aspects should be identified as early as practicable in the EIA process to optimise the contribution of monitoring data to EIA implementation and follow up. Monitoring involves designing the programme, collecting and analysing the data, establishing their linkage to impact management, auditing and other components, and interpretation and reporting of data.
The following points need to be agreed as part of the EMP and conditions of project approval:
- major impacts to be monitored;
- objectives of monitoring and data requirements;
- arrangements for the conduct of monitoring;
- use of the information to be collected;
- response to unanticipated or greater than predicted impacts; and
- measures for public reporting and involvement.
Monitoring requirements should focus on the significant impacts predicted in the EIA report, taking account of:
- the environmental values to be safeguarded;
- the magnitude of each potential impact;
- the risk or probability of each impact occurring;
- the pathways and boundaries of each impact; and
- the confidence in the prediction of each impact.
Monitoring programmes need to be constantly reviewed to make sure that relevant information is being supplied, and to identify the time at which they can be stopped.
Each discipline has established methods for monitoring and data collection. For example, the design of a programme to monitor the impact of a large-scale project involving discharge of toxic waste or effluent into a water body may encompass different methods to measure change in water quality, food chains, fish reproduction, reduction in income from fisheries and its effect on the local community. Generally, monitoring to detect chemical and physical changes is more straightforward than for biological effects or ecological relationships. Socio-economic impacts present a special challenge of measuring changes in collective behaviour and response (see Section 6 â€“ Impact analysis).
The general approach to effects monitoring is to compare the pre- and post-project situation, measuring relevant environmental impacts against baseline conditions. A common issue in all situations is how to differentiate the change attributable to a project from the variability that characterises all biophysical or socio-economic systems. In the real world, as opposed to laboratory experiments, cause-effect relationships are difficult to separate from the interaction of other factors. Eliminating or correcting for these intervening variables is the key to the design and conduct of a scientifically defensible effects monitoring programme.
Typically, this problem is addressed by establishing impact and control monitoring stations. The impact or treatment site is selected to be a receptor of an emission, hazard, event or action from the project. An example would be a water sampling station downstream from an effluent discharge point. The control or reference site is located outside the impact zone, but chosen to be representative of the variability experienced by the impact site. â€˜With versus withoutâ€™ project comparisons then can be made to determine the change or impact that is attributable to the project.
Monitoring programmes result in time series data, which can be analysed by:
- assembling the data in tabular or graphic format;
- testing for variations that are statistically valid;
- determining rates and directions of change; and
- checking these are within expected levels and comply with standards (e.g. water quality).
Some relational changes, such as in chemical constituents in water, can be presented graphically. Longitudinal studies based on numerical data or photographic or descriptive records also provide relevant information on changes and trends. The figure below is an example of monitoring data. It depicts the variation in contaminant levels and their relation to seasonal precipitation, including the effect of an extreme event (drought) on sulphate concentration. Also shown are the independent checks made by the regulatory agency on a proponentâ€™s data.
Monitoring data needs to be interpreted and reported to a non-scientific audience, including decision makers, the affected community and the general public. This may be the responsibility of a regulatory body, monitoring team or multi-stakeholder group, established specifically to bring a broad understanding and a range of views to EIA implementation and follow up. Where different types and methods of monitoring have been carried out, the comparability and quality of the data sets may need to be addressed and reported. Reports should be in plain language and to appropriate technical standards (see also Section 8 â€“ EIA reporting).
Appropriate guidance should be sought when developing an environmental monitoring programme. Typically, some or all of the following issues will be addressed:
- representative impact and reference sites;
- methods for sampling and collection of data;
- independent checks for quality control and assurance of data;
- basis for statistical interpretation and inference of impacts;
- protocols for the conduct of environmental auditing; and
- mechanisms for reporting data and responding to issues that are raised.
Some elements of an effective environmental monitoring programme are listed in the table below. The following steps can help to implement these elements:
- define the scope and objectives of monitoring for each impact;
- identify the sites for observation, measurement and sampling;
- select the key indicators for direct measurement or observation;
- determine the level of accuracy required in the data;
- consider how the data will be analysed in relation to baseline and other data;
- establish a system for recording, organising and reporting the data;
- specify thresholds of impact acceptability; and
- set requirements for management action if monitoring indicates these are exceeded.
When adapting these to scale and circumstances, those responsible for developing monitoring programmes should consider the value of simple observation and reporting, particularly by locally affected parties. Increasing attention is being given to public involvement in the EIA implementation and follow up. For example, stakeholder or citizen monitoring committees have been used in a number of cases. The terms of reference can be written into EIA documentation and include building a long-term relationship with an affected community or group of stakeholders when the project is complex and controversial.
|Monitoring Aspect||Approaches||Adapted from OECD/DAC (1994)|
||A realistic sampling programme (temporal and spatial)|
|Sampling methods relevant to source and/or type of impact|
|Data Collection and Analysis
||A targeted approach to data collection|
|Comparability of data with baseline and other relevant data|
|Quality control in measurement and analysis|
|Systematic record keeping and database organisation|
|Review||Reporting requirements for internal and external checks|
||Provision for input from and response to third parties|
|Presentation of results to the public|
A budget for the monitoring programme needs to be drawn up and the resources and personnel necessary to carry them out specified. Normally, this will be finalised as part of preparation of the EMP. Alternatively, this can be undertaken as a separate exercise, as part of detailed project specifications or incorporated into permitting, licensing or contracting. The latter instruments have advantages in ensuring compliance and enforcement of monitoring and other follow up requirements, but they are not in place in all EIA systems. The costs of EIA related monitoring can vary greatly, depending on the project, the location, the environment affected and the potential significance of the impacts. Other things being equal, the greater the level of uncertainty about potentially significant impacts, the higher the cost of monitoring to obtain information that is relevant to impact management and improved understanding. However, the costs can be offset by the benefits which monitoring brings. These may include immediate savings gained by timely action to correct unanticipated impacts.
Depending on the nature and severity of the impact, this might involve one or more of the following measures:
- stopping or modifying the activity causing an excessive impact;
- imposing penalties or prosecution where conditions and standards are breached; and
- scaling up or adding mitigation measures (in situations where this is possible).
Longer-term gains can also accrue from baseline and effects monitoring. For example the data can be used to establish a reference basis for managing environmental impacts throughout the life of the project. This information will be particularly helpful to the design of an EMS to address the environmental aspects and impacts of the operational phase of the project. Wherever possible, the inputs from monitoring, auditing and other components of EIA implementation and follow up should be integrated into this framework.