Environmental Science Case Study

inside-left-bottom-lgeExtra attention from the DEHP is not something that any business owner looks forward to. Sometimes however, despite a business owner’s best efforts to do everything right, something goes a little wrong and a “show cause notice” is issued. When this happens, Simmonds & Bristow can be there for you, to help get you and your business back on track with the DEHP.

Let’s take a look at some examples that have happened to several of our clients in the past six months.

The Cause: 


Some of the common reasons that our clients were asked to “Show Cause” for were:

  • Failure to Notify DEHP of an incident
  • Exceedance of the allowable daily effluent release volumes
  • Release of non-compliant quality water

It was vitally important that our clients gave an appropriate response to DEHP, as the consequences of not being able to satisfy DEHP would lead to potential prosecution, and expensive fines.

In these specific instances, where there was an exceedance in quality and volume of released water noted by the DEHP,  the receiving environment was unlikely to be impacted. Our clients therefore wanted to assure themselves and DEHP that no environmental harm was caused as a result of these non-compliances.

The Context: Why the ‘sudden’ interest from DEHP for so many of our clients?

Since the Labour Government came into power in February 2015, the Department of Environment and Heritage Protection (DEHP) has steadily been changing its focus from applying standards in development applications and approvals to monitoring and responding to performance. In other words, they are now much more focused on compliance enforcement.

The reason that they have been able to focus less on the approvals side of things, is by introducing and pushing for what are being referred to as ‘Model Conditions’ for sites and industry. These model conditions mean that it takes DEHP much less time to issue Environmental Authorities.

This has given DEHP more resources to focus on Environmental Authority holders’ compliance with their conditions.

The Bad News: What does a Show Cause Notice look like?

If you receive a show cause notice, it will:

  • Explain how your business has been found in contravention to your license (the ways in which you have been non-compliant)
  • Outline potential penalties
  • Provide contact details for the department

The Action Plan: The Role S&B has played in helping our clients provide a response.

Failure to Notify DEHP of an incident:

Whilst there is no appropriate defence for failing to notify of an incident, we have helped our clients to develop procedures and processes to ensure that all incidents are reported in future, and provided training on their duty to notify both under the Environmental Protection Act 1994, and under the sites Environmental Authority.

Exceedance of the allowable daily effluent release volumes:

In order to show that no environmental harm resulted from exceeding the daily allowable release flows, the flow records were investigated to determine if the allowable flow on a weekly or monthly basis has been exceeded. Often we found that whilst the release volume on a specific day was above the limit, only very small volumes of release or no releases occurred for the rest of the week/ month, which means that overall the releases were under the allowed volumes on a longer term basis.

Release of non-compliant quality water:

For non-compliant water quality, we looked at potential dilution factors, if the effluent is stored after the testing point, or mass balances. For example if the effluent is sampled and then transferred into a storage tank or storage lagoon, where it is then released from, the quality of the water coming out of that storage will not be the same as the quality of water that goes in to it, due to dilution by the water already in the storage.

We also carried out soil testing, to show that the soil quality and structure had not been adversely affected by increased volumes or increased contaminants. Common soil tests we undertake include:

  • Hydraulic Conductivity (mm/hour);
  • Field Capacity (%);
  • Wilting Point (%);
  • Moisture Content (%);
  • pH (1:5 extract, pH units);
  • Conductivity (1:5 extract, dS/m);
  • Exchangeable Cations – Calcium, Magnesium, Sodium & Potassium (mg/kg);
  • Exchangeable Sodium Percentage & Sodium Absorption Ratio;
  • Nitrogen, including Nitrate, Ammonia and Organic Nitrogen;
  • Available Phosphorus and the Phosphorus Buffer Index

Lastly we undertook modelling to predict the potential impacts on plants and soil, as well as potential runoff and leaching to groundwater. We do this with the use of MEDLI v2.

The Right Tools: MEDLI vs2

The Model for Effluent Disposal via Land Irrigation, version 2, is a computer model for designing and assessing effluent disposal systems for a wide range of rural and industrial industries, as well as Sewage Treatment Plants. MEDLI was originally developed jointly by the CRC for Waste Management and Pollution Control, the Queensland Department of Natural Resources and the Queensland Department of Primary Industries in 1999. It is now managed and developed by the Department of Science, Information Technology and Innovation (DSITI), with Version 2 of MEDLI having being released in June 2015.

MEDLI predicts the fate of water, nitrogen, phosphorus and soluble salts, based on a series of inputs, including climate data for the specific area, effluent quality and volume, soil profiles – to a depth of 2.0m, and plant types.

Want to learn more about MEDLI v2?

This allowed us to model the system under the Environmental Authority conditions, in terms of volume and water quality, and then compare the outputs, to a model run under the conditions of either increased contaminants, or increased volume, or both. We then determine what impacts if any are likely to have occurred as a result of the non-compliances.

The outputs we would commonly look at to make these determinations are provided in the table below.

Parameter Units Scenario 1 – EA Limits Scenario 2 – Exceedance Concentrations
Irrigation Area Ha 0.95 0.95
Rainfall mm/yr 2,054 2,054
Irrigation mm/yr 1,911 1,911
Soil Evaporation mm/yr 1,373 1,368
Transpiration mm/yr 566 567
Rain Runoff mm/yr 516 512
Irrigation Runoff mm/yr 0 0
Drainage mm/yr 1,510 1,517
Plant Species Blady Grass Blady Grass
No. of Plant Harvests Harvest/yr 4.26 Normal 4.2 Normal
Conductivity of Soil Solution at Base of Rootzone dS/m 0.97 0.96
Average Nitrate Conc. Of Deep Drainage mg/L 3.72 3.5
Average Phosphorus Conc. of Deep Drainage mg/L 0.01 0.01
Design Soil Profile Storage Life based on Average Phosphorus Concentration Years 108 103
Nitrogen Irrigated kg/ha/year 47 52
Nitrogen Uptake kg/ha/year 207 212
Phosphorus Irrigated kg/ha/year 18.4 19.9
Phosphorus Uptake kg/ha/year 16.6 18.1

The Outcome: How did things end up for our clients?

The outcomes depend on the severity and number of incidents, on how much, if any, environmental harm was likely to have been caused and whether the licence holder had notified the DEHP of the exceedance.

In our experience, the “Show Cause” notice from the DEPH does not have to be a disaster. Our clients’ responses to the DEHP were based on facts and good science and engineering. In these cases, we were able to show that our clients had not caused environmental harm and were actively undertaking works to improve the site and its performance to achieve compliance with the Environmental Authority. Ultimately, because of this, the DEHP did not prosecute or follow through with further enforcement actions.

There is however, no excuse for failing to notify the DEHP that an exceedance has occurred. This will likely lead to a penalty fine being issued. Remember, it is the license holders’ duty to notify of any releases to the environment outside of the Environmental Authority license conditions.

Would you like to know more about fines, penalties and environmental harm?

The Point: What does this mean for you?

If you and your business find yourselves on the receiving end of a “Show Cause” notice from the DEHP, contact Simmonds & Bristow and let us help you work through the situation. That’s what we’re here for.