Storage

Good storage is vital for preventing pollution. This is relevant for all sorts of raw materials, process chemicals, fuels, oils, paints, solvents, wastes, cleaners or even foodstuffs.

Good storage practices:

• Have an inventory of all the substances held on site.
• Use containers that are rigid and durable, corrosion-resistant, watertight and rodent-proof.
• Keep lids secured on all storage containers.
• Secure storage facilities and protect from vandalism.
• Store and label according to the HSNO Act requirements.
• Display the appropriate HSNO Act signage
• Locate incompatible hazardous substances beyond the required minimum separation distances, and in separate containment areas.
• Stockpiles of materials should be stored under cover and away from stormwater drains.
• Correctly label all waste skips and cover from the rain.
• Locate emergency equipment and Safety Data Sheets close by.
• Have secondary containment around all storage containers and areas.

Secondary containment

Secondary containment means surrounding your storage containers with a barrier to protect the environment from spills/leaks from bulk vessels. Secondary containment can be concrete walls large enough to contain the total volume of liquids stored within them, or as simple as low nib walls which stop spills from indoor workspaces escaping into yards.

The type and size of the secondary containment you need varies according to the volume of hazardous substance held, and the size of the containers. For details, contact ERMA or see the Hazardous Substance (Emergency Management Regulations) 2001.

Good secondary containment practices:

• Contain all of the pumps, pipes, valves, flanges and decanting vessels within the secondary containment, to catch any leaks, spills or overflows.
• Locate loading points inside the secondary containment.
• Meet all of the HSNO Act requirements.
• The secondary containment is the appropriate size.
• All secondary containment should be roofed, or have procedures for emptying rainwater without causing pollution.
• Floors, walls and pipework of the containment should be impervious to the materials stored.

Handling and use

If you use materials such as oil, solvents, acids, paints, cleaners, pesticides and other chemicals, then your site has the potential to pollute the environment. Poor handling can also lead to the loss of material, risks to health and safety and a waste of time and money cleaning up after an incident.

Good handling practices:

• Check and maintain filling and transfer equipment regularly.
• Use funnels, drip trays or buckets when decanting and transferring materials.
• Routinely clean-up and suitably dispose of any spills during refuelling or materials transfer.
• Put lids on all containers when moving around the site.
• Secure all loads on forklifts and other vehicles.
• Follow the instructions of the Safety Data Sheets in terms of handling and use of materials.
• Make sure all staff handling materials are adequately trained.
• Designate and mark out loading/unloading areas and routes for transferring materials.
• Consider either roofing the loading/unloading areas or isolating these areas from the stormwater system.
• Only store drums and containers in areas with adequate secondary containment, even for short periods.
• Keep spill kits and other emergency equipment close to handling areas such as refueling points.
• Contain any leaks and spills that may occur during transfer.
• Supervise deliveries of oil and hazardous materials.
• Prevent overfilling by fitting automatic cut-off valves to delivery pipes.
• Fit automatic shut-off valves to fuel hoses to reduce the likelihood of spills from overfilling.

Water pre-treatment

Sumps and interceptors – the last line of defence for pollution prevention

To protect local waterways from the runoff from your site, all stormwater should have treatment prior to discharge from your hardstand areas. Hardstand areas are carparks, storage areas, driveways and other sealed or compacted surfaces on your property.

Sumps and interceptors are the last chance to prevent pollution from your site entering waterways. Good storage, handing and use of materials and hazardous substances are the first lines of defence. Sumps help to settle out sediment before water goes into the stormwater system. Interceptors are designed to trap oil and fuel on the surface of the water and prevent them being discharged to the stormwater system. If your site has a refuelling area, car park or vehicle wash down area, you should have interceptors fitted.

Interceptors are also installed to treat run-off or discharges that are piped to the sewer, to reduce the oil and grease load on the wastewater treatment plant.

Inspect regularly as part of your maintenance programme

Sumps should be inspected regularly to check the level of sedimentation and to ensure that they aren't blocked or over-flowing. Inspection frequency will depend on the nature of your business and how much sediment runs off your site.

Interceptors should be inspected regularly to ensure that they are not full, blocked or overflowing. Inspection frequency will depend on the nature of your business. If you handle fuel or oil, or wash vehicles on-site, your inspection may be more regular than if you only have a driveway and carpark.

To start with, check sumps and interceptors on a monthly basis and record your findings. After 6 months, review and adjust your monitoring to suit. Remember to allow for seasonal changes, because the material captured in treatment devices can change depending on things such as rainfall intensity or leaf litter.

Interceptors and sumps should also be inspected following any spills on your site.

Cleaning out

Sumps should be cleaned out once the sump reaches 60% sedimentation by a reputable waste contractor. Otherwise your sump will not work so well and more sediment will pass through it into the stormwater system.

Interceptors should be cleaned out regularly by a reputable company or if there is a significant quantity of product or oily material (more than 3 mm) or sediment (more than 150 mm) in the device. Ensure that the waste removal company ‘recharges’ the interceptor with clean water after cleaning.

Good housekeeping

Some housekeeping practices can help reduce the amount of sediment, fuel and oil getting into your sumps and interceptors. Some key tips are given below. For more information see the housekeeping sections of the Pollution Prevention Guide.

• Use dry cleaning methods such as wiping-up and sweeping spills rather than hosing.
• Ensure all mechanical equipment is properly cleaned and maintained to reduce spills and leaks of fuel and oil.
• Never pour any type of oil down the sewer or the stormwater system.
• Use detergents with a 'quick break' time which help with oil separation.
• Use cleaning products that have a pH of 6-10 at working concentration.

Waste disposal

Appropriate treatment and/or disposal of all liquid, hazardous and solid wastes is essential for preventing pollution.

Do’s

• Ensure that as much solid waste is recycled or reused as possible, and otherwise disposed of to:
  • landfills
  • cleanfills (for inert waste such as concrete, soil or bricks).
• Make sure you have a trade waste consent if you are a commercial or industrial trade premises discharging any process water to the sewer (other than just sanitary waste).
• Find a responsible waste operator to take care of your waste at a licensed treatment and/or disposal facility if your trade waste is not suitable for direct disposal into the sewer.

Don’t

• Don’t discharge anything to the sewer other than sanitary waste, unless you have a trade waste consent and are complying with any conditions on this consent. If you are unsure whether or not you need a trade waste consent, contact your local district or city council.
• Don’t dispose of liquid waste via stormwater systems. These only drain rain. Contaminants or wastes that get into stormwater pipes end up in our rivers, harbours or groundwater.

Auto painting and panelbeating

If your day to day activities involve painting, sanding/wet sanding, or any other vehicle body repair activities using paints, solvents, thinners or detergents, then you have the potential to pollute the environment.

Easy tips to prevent pollution:

• Do wet sanding inside a building.
• Allow waste water to dry before sweeping up the paint residues and disposing of them in a waste bin.
• After dry sanding, sweep-up any paint chips and dust residues and dispose of them in a waste bin.
• Always use drip trays when transferring or draining paints and other liquids.
• Store all paints, thinners and other liquids under cover to prevent rainfall washing out pollutants.
• Wash vehicles and equipment down so that the wash water enters a sewer gully trap and not a stormwater drain. You may need approval from the city or district council to use the sewer.

Concrete pouring and cutting

If your day to day activities involve the handling of concrete and other cement based products, then your activity may affect the environment.

Concrete cutting and the washing of fines

If cooling water is needed or washing needs to be carried out on site, ensure that there is no discharge to the environment.

• Divert runoff to a grassed or unsealed area where it can soak into the ground.
• Block a receiving drain and pump the waste water to an area where it can evaporate or soak into the ground.
• Only discharge filtered wash water (i.e. filtered via haybales) to the sewer with the approval of the local council.
• Wash the fines off freshly laid concrete to the side, not into the stormwater drainage system.
• Never wash concrete products in areas where the wastes and associated wash water will drain to a stormwater drain or stream.
• Clean up all spilt material immediately and dispose of wastes in a bin in such a manner that they won’t leak out.
• Ensure all workers and/or contractors are aware of these requirements.

Concrete trucks and equipment

• Use a specifically designed wash area, which either discharges into the sewer or contains all waste water in a sealed pond or tank for re-use as concrete make-up water or for equipment washing.
• On any large construction sites requiring multiple deliveries, ensure there is a designated wash out area which allows water to soak into the ground and not run overland into the stormwater system.

Vehicle and equipment washing

Whenever a vehicle or piece of equipment is washed, the waste water contains contaminants that can harm our environment.

If you wash vehicles or equipment, you need to have at least one of the following to prevent pollution from your site:

• A properly designed and designated wash facility.
• A contract with a vehicle/equipment cleaning firm.
• A formal policy ensuring that all cleaning activities are carried out appropriately.

Tips to prevent pollution

• Use a dry wash method - anti-static brushes, wet rag/dry rag, bucket and rag - on vehicles, containers and equipment.
• Take vehicles, containers or equipment to a responsible commercial washing facility with a sewer connection or recirculating system.
• All commercial wash water containing cleaning and/or degreasing agents must be disposed of as a trade waste into the sewer, with the approval of the local council or via a commercial waste contractor.
• If you are a car dealer who wishes to keep display vehicles clean on your yard, then you may use just cold water, with no additives (ie detergents), to rinse off the settled film from vehicle panels and windows.

Earthworks, construction and demolition

If your day-to-day work includes earthworks or construction, there is the potential for adverse environmental effects from sediment runoff, stockpile runoff, chemicals, paint and other contaminants. With good management of your site, sediment and other contaminants can be contained, and pollution prevented.

Sediment

During earthworks, construction and demolition, the risk of water pollution being caused by silt entering surface waters is high. This is from any development; house sites, industrial sites or subdivisions.

Adverse impacts of erosion and sedimentation on waterways include:

• Smothering of the stream bed, reducing, fish, plant and insect life.
• Blocked channels, causing increased flood risk.
• Loss of good topsoil.
• Damage to the site resulting in possible damage to structures and site facilities.
• Problems for downstream users including those using water for irrigation, stock and domestic water supplies, as well as the filling of dams with silt.
• Reductions in aesthetic and recreational values.
• Damage to property and public utilities from sediment settling out on property or in pipes.
• Effects on matters of significance to Tangata Whenua, including:
  • Water quality and the mauri of waters,
  • fishery values,
  • customary rights, and
  • kaitiaki initiatives and responsibilities.
• Safety problems when soil, litter and debris are washed around the site and surrounding areas.

Environment Canterbury’s Erosion and Sediment Control Guidelines provide information on effective erosion and sediment control. These guidelines are for developers, consultants and contractors who are involved with earthworks and for city, district and regional council staff who are assessing consent applications and doing compliance monitoring of consented works and permitted activities under the Resource Management Act.

Environment Canterbury’s Small Sites Guideline is for building on small, individual sites.

Stockpiled materials

During construction or demolition there is the potential for pollution from stockpiled materials. Common types of stockpiled materials that can contaminate surface runoff include:

• Treated timber which may contain copper, chrome, arsenic or boron.
• Metal dumps which may contain oil.
• Bare soils or other sediments which can smother stream life.
• Compost or rotting vegetation which will use up oxygen if washed into waterways.

If your stockpiled materials are exposed to rain, there is the potential for contaminated stormwater to run off your site. Dust may also be a problem from stockpiled materials in windy, dry conditions.

What you can do:

• Store materials on flat ground, at least 10 metres from the nearest drain or waterway.
• Dampen down stockpiled materials to minimise dust blowing around, but do not add enough water to cause runoff.
• Cover stockpiles to avoid contaminated runoff.

Chemicals, paint and fuels

On development sites, there are environmental risks with the storage and use of mobile fuel containers, and with the large range of solvents, paints, glues, adhesives and cleaning agents.

If not maintained and checked, mobile fuel storage tanks can leak into the ground or waterways.

Tanks should be stored at least 10 m away from a water course. Spills should be cleaned up immediately.

Keep all other hazardous materials, including paints and glues, under cover in one place (preferably where they can be locked up after-hours), correctly labelled and with drip trays and other protective equipment. Reuse, recycle or dispose of the leftovers and empty packaging at your local transfer station.

Electroplating

Chemicals used by the electroplating industry include:

• Acetic acid
• Acetone
• Ammonium hydroxide
• Chromic acid/chromates
• Chromium oxide
• Hydrochloric acid
• Nitric acid
• Sulphuric acid
• Trichloroethylene

These chemicals can be harmful to the environment if they end up in the stormwater system through spills, leaks or illegal discharges.

If you are an electroplater, you may need an air discharge consent and/or a stormwater consent under the Proposed Natural Resources Regional Plan. Please contact Customer Services for more information.

The chemicals you use for electroplating are now controlled by the Hazardous Substances and New Organisms (HSNO) Act 1996, which replaces previous laws such as the Dangerous Goods Act 1974 and the Toxic Substances Act 1979.
If you want to continue using some of these substances, HSNO regulations may require you to have the right Test Certificates.

You may need:

• A Location Test Certificate for your premises (previously a Dangerous Goods Licence).
• An Approved Handler Test Certificate for employees responsible for the handling of certain highly hazardous chemicals.

Fuel and oil

If you use and store diesel, petrol or engine oils in your business, they must be handled and stored carefully to avoid pollution. Oil is one of the most common causes of water pollution and, because of the way it spreads in water, even a small quantity can cause a lot of harm to plants and animals that come into contact with it. Also it can also make water unfit for drinking and irrigation. The washdown water from cleaning vehicles and equipment can also contain oil, as well as dirt and other chemicals, which must not be allowed to reach the stormwater system.

Tips:

• Have good storage practices.
• Follow strict procedures to minimise spills while loading, unloading and transferring materials.
• Maintain vehicles on a regular basis to prevent leaks.
• Store waste oil securely and remove it regularly.
• Dispose of vehicle wash water via the trade waste (sewer) system so that stormwater or local waterways are not contaminated.
• Install oil interceptors in refuelling or carpark areas and maintain oil interceptors regularly.
• Ensure all tanks and secondary containment meet HSNO requirements and are regularly maintained.
• Know how to deal with a spill and ensure all spills are cleaned up immediately, especially in outdoor areas.

Controls

The use, importation, manufacture and sale of hazardous substances is controlled by the Hazardous Substances and New Organisms (HSNO) Act. What you need to know will largely depend on what you have, how much you have and how you store it.