Appendix D: Items to be included in a water assessment plan for a composting or related composting facility

Principal component

Subparts

Groundwater and subsoil monitoring network

• documentation describing the background characteristics of the groundwater
• unless the preliminary water assessment of the site (Appendix A) has established that the facility poses minimal risk to groundwater, the water assessment plan should include:
  •  a scale drawing showing the location and depth of groundwater monitoring bores
  • documentation outlining the groundwater hydraulics and the procedures used for bore development and bore security (refer to Section 5)

Discharges to surface water bodies (where relevant)

• a scale drawing of discharges to surface water bodies (including creeks, rivers and dams)
• documentation outlining the predicted discharge conditions (e.g. frequency and volume)

Surface water bodies monitoring network

• documentation that describes the background characteristics of the surface water bodies before composting and related organics processing activities start
• a scale drawing of monitoring points for all surface water bodies (such as creeks, rivers and dams), which includes:
  • surveyed monitoring points established upstream and downstream of the facilities
  • discharges from the premises to surface water bodies
  • a minimum of one monitoring point per surface water body located downstream from (for flowing or perennial waters) or near (for still waters) the processing area. It is advisable, however, to locate one reference monitoring point per surface water body - upstream (for flowing waters) or distant (for still waters) from the processing area - in order to establish whether any detectable change in water quality has been caused by the processing activities.
    

Indicator parameters and limits for routine monitoring and assessment of waters

• a list of indicator parameters and limits for routine monitoring and assessment of waters (including groundwater, surface water bodies such as rivers, creeks and dams) and leachate
• documentation that gives details of how the parameters were selected and limits for the specific indicators adopted will provide an indication of all the possible types of pollution that may occur.

The indicator parameters chosen should be based on the preliminary water assessment of the site (Appendix A) and the types of organics processed as the facility. The following parameters could be used in identifying and assessing waters:

• alkalinity, ammonia, calcium, chloride, fluoride, iron, magnesium, manganese, nitrate, organochlorine pesticides, organophosphate pesticides, pH, total phenolics, polycyclic aromatic hydrocarbons, potassium, sodium, sulfate and total organic carbon (TOC).

The regular monitoring of electrical conductivity (sometimes written as EC) may be used for preliminary indication of changes in water quality. This is because EC is a measure of the ability of water to conduct an electric current and is sensitive to variations in dissolved solids, mostly mineral salts. Increases in the measured values of EC for waterbodies are often good warnings of changes in the abovementioned indicator parameters.