Monitoring

Regular environmental monitoring enables us to not only comply with certain consents but more importantly fully understand the surrounding environment and the impact our activities are having, or potentially could have.

Some environmental impacts are very visible and easy to detect such as vegetation die off or algal growth in waterways. However many impacts are invisible such as heavy metal concentrations in sediments or contaminants dissolved in water.

Our Environmental Field Officer, Ainsley undertakes regular onsite environmental monitoring to check for any changes or impacts.

Dairy farm water monitoring

As the farm is at the head of a catchment it is an ideal location to understand the effects a single dairy farm can have on water quality. All surface channels begin on the farm, with some from springs that bubble up out of the limestone rock.

Water samples are taken from nine sites that include a mixture of surface water channels and tile drains that exit the property. Monthly monitoring analyses:

E-coli
Nitrate
Nitrite
Dissolved Reactive Phosphorous
Total Ammoniacal Nitrogen
Turbidity.

Regular monitoring since the dairy farm was first established in 2014 has meant:

Various contaminant concentrations were identified at different times of the year. This data has been used to help mitigate the dairy farms environmental impact on water quality.
Regular water quality monitoring has given rise to projects to improve the water quality including riparian management, environmental education and best management practice implementation for wintering.
Larger ongoing projects are now underway to include the use of bunding and wetlands to reduce sediment and nutrient loss on the hill country.

Landfill gas monitoring

The AB Lime Landfill can be described as a biological system with factors such as gas composition and flow changing constantly due to environmental conditions.

Gas monitoring is carried out at each of the 20 gas well heads in the landfill. This sample is then analysed and the composition recorded.

Gas compounds that are monitored include:

Methane
Carbon Dioxide
Oxygen
Hydrogen Sulphide
Carbon Monoxide.

This information allows AB Lime to understand the gas composition and quality from different areas in the landfill. Gas composition is very important for complying with the Emissions Trading Scheme and for using the gas on site as a fuel source. Gas is captured at the landfill by a large pipe network and is currently combusted at the gas flare.

Landfill Underdrainage Water Monitoring

To ensure the integrity of the series of impermeable layers associated with the landfill liner any underdrainage water that may flow beneath the landfill is monitored monthly for contamination.

Seven groundwater monitoring bores are located beyond the landfill footprint - above and down gradient to provide a full environmental comparison. These are sampled and independently analysed twice a year.

Controls are in place to be able to collect any contaminated underdrainage water and direct it to the leachate collection system if necessary to prevents escaping into the environment.

Surface Water Monitoring

Surface water that flows out of the quarry is monitored continuously. Continuous water quality and flow sensors take measurements more than once a second for parameters such as:

Turbidity
Electrical Conductivity
Temperature
pH
Dissolved oxygen
Flow.

This continuous data is valuable and is used to show the impact of rainfall events on water quality. More importantly this water quality monitoring allows AB Lime to pick up any unusual results or patterns as they occur in real time and address any issues immediately.