Best Practice Guidelines for Stormwater Pollution Prevention
MANAGING WASH WATER WASH BAYS AND OTHER OPTIONS FOR WASHING VEHICLES, EQUIPMENT, OR HARDSTAND AREAS
MANAGING WASH WATER
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Contents SECTION
PAGE
Introduction
2
How to manage wash water
4
1. Setting up your own purpose built wash pad
4
2. Using mobile washing operators
7
3. Using vacuum trucks for wash water collection and disposal
7
4. Using a wash bath or self contained parts washing machine
8
5. Using a certified commercial wash facility
8
REPO TO T RT POLL U AUR ANG TION A C PH ( OUNCIL CITY 07) 577 700 0
Information in the book is correct at the time of publication December 2010
MANAGING WASH WATER
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INTRODUCTION If your day to day activity involves the washing or waterblasting of:
factory areas
workshops
outside yards
equipment
or vehicles
…then your business has the potential to pollute the environment. You need to ensure all wash water is disposed of properly. This booklet explains the different disposal methods that are appropriate for businesses and industries.
What is wash water? Wash water is produced from the washing of sites, equipment or vehicles. It is classified as a pollutant because it almost always contains contaminants. Contaminants in wash water might include:
phosphates
solvents
acids
oils
fuel residue
sediment
heavy metals like lead, zinc and copper.
It is illegal to discharge wash water into stormwater drains, waterways or the sea. You can be fined for causing pollution and even sent to jail for serious cases. Fines can be as high as $600,000 for companies and $300,000 for an individual.
How can wash water cause pollution? H WASHING WIT Y" STILL "WATER ONL LUTION! CAUSES POL
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BEST PRACTICE GUIDELINES FOR STORMWATER POLLUTION PREVENTION
Stormwater drains lead straight to waterways. When contaminated wash water gets into the stormwater system, it can directly affect animals and plants. Oily films can build up on surface waters which limits sunlight and oxygen. This makes it difficult for plants to get energy and for animals to breathe and find food. Chemicals and heavy metals can build up in plants, animals and also in sediments, causing long term effects for both aquatic life and for human health. Contamination of soils and groundwater can also occur.
"BIO OR " DEGRAD PRO ECO FR ABLE" D IE POLL UCTS W NDLY" ILL UT INTO ION IF W CAUSE A WAT ERW SHED AYS
What you need to know:
Washing your site, vehicles, equipment or parts can cause water pollution if the wash water is not managed properly.
You can be fined for causing pollution.
It is not okay to wash work trucks or equipment on the open yard with wash water entering stormwater drains.
Washing with water only will still produce contaminated wash water.
If you undertake washing of engines or engine parts you must have a dedicated facility set up for this.
It is not okay to wash down your factory or workshop floor or yard without containing the wash water.
All wash pads must have a trade waste consent from Council.
All washpads must be roofed – rainwater that enters the wastewater system contributes to overloading of the network which can cause sewer overflows to the harbour.
The polluter pays – If you are not prepared to protect the environment then you shouldn’t be in the business.
Biodegradable?
Vehicle being washed with wash water that flows directly to the stormwater system.
Even when chemicals and detergents are not used, the material you are washing off will still be contaminated. Although “biodegradable” or “eco friendly” detergents are designed to break down quickly in water, the initial impact on waterways will be as harmful as with any other detergent. Biodegradable does not mean environmentally friendly!
Wash water containing detergent draining directly into a local stream.
MANAGING WASH WATER
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HOW TO MANAGE WASH WATER There are some options for controlling wash water produced from your site.
1.
Set up your own purpose built wash pad
Use a mobile washing operator who can collect the wash water for appropriate disposal
Call in a vacuum truck operator to collect wash water during wash down
Use a self contained washing unit that can recycle all wastewater
Take vehicles or equipment to a certified commercial wash facility (car or truck wash)
SETTING UP YOUR OWN PURPOSE BUILT WASH PAD A purpose built wash pad draining to Council’s wastewater system can be set up on your site for washing of parts, equipment or vehicles.
Minimum Requirements A wash pad must be constructed to ensure rainwater cannot enter the Council’s wastewater system and that over-spray cannot reach the Council’s stormwater system. The wash pad must be constructed to meet the following criteria: The
wash pad must be suitably sized and/or shielded to ensure containment of all wash water. Over-spray must be prevented as it has the potential to drain to Council’s stormwater system.
4
The wash pad must be roofed to prevent rainwater from entering Council’s wastewater system.
The wash pad must be raised sufficiently above the finished ground level of adjoining areas to exclude rainwater runoff.
BEST PRACTICE GUIDELINES FOR STORMWATER POLLUTION PREVENTION
UTION L L O P G CAUSIN OST YOUR C TO COULD NY UP A P M O C 00! $600,0
ALL W A C ASHPA ONS D ENT S NEED COU F NCI ROM L
Unroofed wash pad draining to sewer via 3 stage oil and grit trap – requires roofing
Fully roofed car wash draining to sewer via 3 stage oil and grit trap
A wash pad must be set up with a treatment system to treat wash water before it enters Council's wastewater system. This treatment system must meet the following criteria:
The minimum level of treatment is gravity separation. The system must be designed to produce a discharge that is substantially free of settleable and floatable material. “Substantially” equates to a minimum retention time of 30 minutes for 70% of the separator’s wet volume.
The system must include a grit trap followed by a 2 or 3 stage ‘oil and sludge’ trap. Grit traps retain grit and debris; oil traps retain oil, sludge and floatable material.
Depending on the activity and nature of any cleaning agent used, significant amounts of the oil may become “emulsified” (mixed with water) and pass through a gravity separator. To prevent excess oil from entering the wastewater system, quick-break detergents may be required which rapidly break oil emulsions.
The system must be capable of consistently complying with Council’s Trade Waste Bylaw and the discharge quality referred to above.
The system must include a Council approved specific design.
The system must have a Council approved access point for sampling.
The system must have a dedicated wash pad water meter to measure the volume of discharged wash water.
3 stage oil and grit trap
Illegal washpad draining directly to the stormwater system
MANAGING WASH WATER
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FORM OF APPLICATION UNDER THE TRADE WASTES BYLAW OF THE TAURANGA CITY COUNCIL
Trade Waste Consent
The Trade Waste Officer Tauranga City Council Private Bag
A trade waste consent is required to discharge wash water trade wastes from wash pads to Council’s wastewater system. The following conditions may apply as part of the trade waste consent:
TAURANGA 1.
I/We __________________________________ being the occupier(s) of trade premises at ___________________________________________________________ and there carrying on the business of __________________________________ and trading as __________________________________________________ request the consent of the Council to the discharge of trade wastes to the Council’s sewers in accordance with the terms of the Tauranga City Council Trade Wastes Bylaw. Contact details are:
Oil and grit traps must be cleaned and maintained regularly and a service contract with a reputable contractor is required. A cleaning frequency may be also specified in the consent. The consent-holder may also be required to submit proof that the trap is being maintained. Failure to maintain traps will result in the trade waste consent being cancelled and may lead to the withdrawal of Council’s wastewater service.
2.
Self-monitoring conditions and a monthly status report must be submitted to Council.
A trade waste service charge may apply.
_____________________________________________
Phone Number
_____________________________________________
Postal Address
_____________________________________________
This request relates to: (a)
or
An already existing discharge;
(b)
To a proposed new discharge;
(c)
To a proposed change in: (i)
Volume of wastes
or
(ii)
Rate of discharge;
or
(iii)
Composition of wastes previously discharged
(strike out that which is not applicable) 3.
Company Contact Person
The proposed new discharge, change in volume, rate, or composition of wastes will commence from:
Application Form .doc
Building Consent A building consent must be granted by Council for any structural and drainage works that are required for wash pad construction. Contact Council’s Building Consents Officer for further information. If Council’s wastewater system is not available, discharge to ground soakage or direct to natural waters may be permitted by the Bay of Plenty Regional Council subject to resource consent. Contact the Regional Council's Consents Officer for further information. The above requirements for wash pads form the minimum acceptance standard as at November 2010. These rules are subject to change. For Trade Waste consent application forms and confirmation of requirements contact the Trade Waste Officer, Tauranga City Council.
AD WASHP S OR EPTOR INTERC S MUST BE RAP Y GRIT T ULARL G E R D E CLEAN
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BEST PRACTICE GUIDELINES FOR STORMWATER POLLUTION PREVENTION
2.
USING MOBILE WASHING OPERATORS Mobile operators will come to your site, carry out necessary washing of site areas, equipment or vehicles and safely collect and appropriately dispose of all wash water.
DO N OT WOR HOSE D OW KS YAR D AR HOPS O N R EAS YOU UNLE COL WAS LECT T SS H HW ATER E
Depending on the frequency of washing required, using a mobile operator may be cheaper and more convenient than taking your vehicles or equipment to a certified wash facility. Before using a mobile operator you should make sure that they have been consented by Council to carry out their activity. Please check the Yellow Pages for local operators.
3.
USING VACUUM TRUCKS FOR WASH WATER COLLECTION AND DISPOSAL Vacuum tankers or “sucker trucks” can be used effectively to collect significant volumes of wash water during cleaning. Operators can block off stormwater sump outlets and vacuum wash water up as it enters the sump or divert wash water to a collection point, e.g. using sand bags. Vacuum trucks are a good solution following spills or when a yard or workshop area requires water blasting. Some vacuum tankers come with their own water blasting units.
Vacuum tanker – “sucker truck”
Vacuum tankers can also be used to clean out oil and grit traps. Any wash water will be contaminated so you need to ensure tanker operators dispose of waste at a facility consented to accept it. Please check the Yellow Pages for local waste disposal operators.
Vacuuming out an oil and grit trap
MANAGING WASH WATER
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4. USING A WASH BATH OR SELF CONTAINED PARTS WASHING MACHINE
A wide range of vehicle parts washers are available. A wash bath may be as simple as a sink with a drain into a wastewater holding tank. Advanced machines may be self contained, fully automatic with water recycling. Wash baths must have a holding tank big enough to hold all wash water that will be generated. Wash baths require regular collection and disposal of waste product to a facility authorised to accept this waste. Solvents and oily wastewater must not be put into Council’s wastewater network, nor should wash water be tipped down the sink.
Wash bath
Automatic parts washing machines may be more cost effective than using staff to clean parts manually. These machines reuse the water and the dirty sludge is held in a tank for disposal. Parts washing machines would usually require servicing and waste disposal every two to three months. There are a range of companies who can supply these products for sale or hire - hire costs may incorporate servicing and waste disposal charges. Please check the Yellow Pages for local suppliers and operators.
5.
Automatic parts washing machine
USING A CERTIFIED COMMERCIAL WASH FACILITY Taking vehicles to a commercial car or truck wash is simple and there are a number of sites in Tauranga available. If you wash vehicles less than once a week this is likely to be a cost effective option.
Automatic Carwash
Commercial car and truck wash facilities are required to have a trade waste consent and an approved treatment system for disposal of wash water to the wastewater system. There are also facilities that can degrease entire engines, or other vehicle parts, which cannot be carried out at a regular car wash. Please check the Yellow Pages for local operators.
T
Car wash facility
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BEST PRACTICE GUIDELINES FOR STORMWATER POLLUTION PREVENTION
US IS J N I DRA IN THE OR RA F
Marathon 53571
