Industries with wash down bays are required to remove contaminants from waste water before discharge. Wash down areas such as truck wash bays must remove suspended solids, fat, oil, grease and hydrocarbons, prior to discharging to sewers, leach drains, ponds, holding tanks or other approved discharge sources. Car wash sites such as single and multiple bays in manual hand car wash sites, self serve, touch free and tunnel car wash systems, all require low cost, low maintenance solutions.
Mining water treatment requires especial care and cutting edge technology since hydrocarbons, oils and grease require removal to adhere to strict hydrocarbon discharge standards on all mining sites. Drainage considerations, sump designs, flow rate calculations, equipment specification and solids handling management are taken into consideration when devising wash bay solutions for the mining industry.
Waste water treatment solutions are available to suit all industries from small workshops to large scale mining operations as well as traditional or above ground portable wash bays. These are usually cost effective and easy to install. Cost effective rain water harvesting systems and water recycling systems may be used to minimise mains water use and disposal costs.
Reasons for wash bays being noncompliant include; discharging wash water to stormwater drains, using waste water treatment equipment which is outdated, the pH levels of discharged water being outside of approved limits and not utilising secondary treatment procedures that are necessary to remove certain contaminants.
Wash down bays may be retrofitted to meet AQIS (Australian Quarantine Inspection Services) criteria. AQIS wash down bays require treatment and/or recycling systems to comply with water quality requirements. Installing systems such as oil separators, 100 micron filters, water recycling systems and first flush diverter systems ensure that the wash down bay adheres to both AQIS criteria as well as trade waste requirements.
Furthermore, ascertaining that discharge is to a sewer or approved AQIS discharge tank, using bio degradable quick break degreasers and detergents and only helical rotor or diaphragm pumps to pump wash water through the treatment system keeps the wash down bay authority compliant. When connecting to sewerage it helps to check local trade waste guidelines.
It is also important to avoid the use of traditional solvent-based degreasers that do not have quick break properties and not to dispose of any coolants, acids, caustics or chemicals through the water treatment system. Workshops or other areas should not be allowed to discharge water via the AQIS water treatment system and wash down water should not be discharged directly to the stormwater drain. Obtaining AQIS approval before installing the wash down bay avoids having to make costly changes later on.
Businesses should enter into a maintenance agreement for servicing of their car wash equipment in accordance with regulations. Regular servicing of a waste water treatment system makes it more efficient and able to perform at its maximum capacity for a longer time. This also decreases the possibility of breakdowns and repairs, keeping a minimum.