Land

Theme commentary
Tony Gleeson, Synapse Research & Consulting
Alex Dalley, Ministry of Agriculture Fisheries and Forestry, Dili, East Timor
prepared for the 2006 Australian State of the Environment Committee, 2006

Pollution to and from land

Reporting on solid waste and land pollution is plagued by a lack of national datasets.

Landfill

Australia’s per capita waste disposal rate is estimated to be 1.1 tonnes per year, which is the second highest in OECD countries, behind the United States of America (OECD 1999).  

Unfortunately there is no national data collection for the volume of waste disposed in landfill nor is there national data collection for the area of land that landfill sites take up. This information is collected by local governments with no standardising of data collection.

Pollutants

Since 1998 the National Pollutant Inventory (NPI) has measured emissions of substances to air, land or water. The NPI is an Internet database that displays information about the emissions from industrial facilities and diffuse sources of 90 different substances. The NPI is legislated for in every state and territory and all facilities or businesses that exceed NPI chemical use thresholds are required to report on their use annually, although not all do so (see the NPI website .)

Certain industries, including all facilities involved in agricultural production except for intensive livestock raising facilities, are excluded from the NPI, even though they may ‘trip’ the reporting thresholds. As a result the NPI does not keep information on the total amounts of phosphorus fertiliser applied to the land.

Ammonia is the most common pollutant to land as a result of agricultural practice . In 2003‑04, ammonia emissions to land accounted for 48 per cent of the total emissions of NPI substances to land .

The main producers reporting ammonia emissions are intensive animal production facilities. Of these, on the basis of the reported data, beef feedlots would seem to be by far the largest. In 2003–04, intensive beef production facilities (feedlots) reported emitting approximately 40 million kilograms of the total 55 million kilograms of ammonia. In comparison, the reported contributions from intensive poultry and pig production were negligible. However, as yet, only a relatively small proportion of poultry and pig establishments are reporting emissions to the NPI.

Because all other agricultural facilities are excluded from the NPI, the real emission of ammonia to the land through animal production is likely to be much greater than that reported. This is further supported by data on the nutrient loads of rivers in the Murray–Darling Basin. Nutrient loads  were found to be greater than natural levels for over 90 per cent of river length in the basin (NLWRA 2001b).

Residues

Agricultural or industrial chemicals and their breakdown products are known as residues. Unless care is taken, these residues can find their way into the foods we eat and export.

The National Residue Survey  monitors the chemical residue levels of agricultural products and records when chemicals occur in greater concentrations than limits established for trade (domestic, export and import) or human health reasons.

National Residue Survey data for January 1998 through to July 2004 suggest a slight downward trend in the number of residues and metals found in foodstuffs in excess of permitted levels.  This may be due to improvements in the handling of chemicals through programmes such as DrumMuster or through an increase in the numbers of land managers undergoing training in chemical handling and use.

Chemical residues would directly hamper both domestic and international trade and presumably this is a major driver for both the collection of relevant data and for improvement against the chosen indicator. Clearly, when there is a strong economic imperative to do so, we can act on a national level to address an impact of our activities. The situation for chemical residues illustrates the importance of using indicators for environmental performance against which progress can be monitored reasonably simply and that have both direct environmental and economic significance.