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Silverstream - S1 Introduction

Please note: Rates on this page are from 2008 and are not current, please refer to the Hutt city council website for up to date rates   
http://www.huttcity.govt.nz/Services/Rubbish-and-recycling/Fees-and-charges/   

S1.1 Waste management services in Hutt Valley

S1.1.1 Regional overview

The Hutt Valley, northeast of Wellington City, is shared by two territorial authorities: Hutt City Council and Upper Hutt City Council. Lower Hutt City has a usually resident population of 97,701, according to the 2006 census; it is the main industrial centre for the Wellington region. Upper Hutt City has a usually resident population of 38,415.

The region is bounded by Wellington Harbour to the south and by ranges of hills to the north, east and west. The Hutt Valley’s economy is predominantly property and business services, construction, retail, wholesale, trade and manufacturing.1

There are two landfills situated in the Hutt region: one south of Silverstream and one in Wainuiomata. Both landfills are run by Hutt City Council. The Wainuiomata landfill is 1.5 km from Wainuiomata CBD on Coast Road and is operated by Wainui Landfills Ltd. The Silverstream Landfill is about 10 km from the Upper Hutt CBD and 13 km from the Hutt City CBD on Reynolds Bach Drive, Hutt City, and is operated by Excell Corporation Ltd. Both are open to the general public and commercial waste operators. Wainuiomata is geographically isolated, and the gate charges at the two landfills are the same, so it is likely that most commercial waste from Wainuiomata is disposed of at the local facility.

Other landfills in the region that potentially affect waste flows at Silverstream are Southern Landfill, 34 km south of Silverstream, on the southern side of Wellington, and Spicers Landfill, in Porirua, 27 km west of Silverstream.

Seaview Recycle and Transfer Station has been opened recently in Seaview, Hutt City. Refuse from the transfer station is disposed of at Wainuiomata Landfill.

Previous studies undertaken for the Ministry for the Environment by Waste Not Consulting indicated that approximately 85 per cent of the waste entering Silverstream Landfill originates in the Hutt region, and that less than 5 per cent of the waste generated in the Hutt region was disposed of at landfills outside the region.2

The main waste operators in the Hutt valley are Waste Management New Zealand (part of Transpacific Industries Group Limited), AllBrite Industries (owned by Transpacific Industries Group Limited), and Wheelibin Company (owned by Waste Management). Dimac Bins Ltd provides a range of collection services, and there are several smaller operators also providing services.

S1.1.2 Waste services for the residential sector

Both Hutt City and Upper Hutt City Councils provide a weekly user-pays kerbside collection of domestic bagged refuse. Bags are available for sale for $1.40 each at council offices, and these cover the cost of collection and disposal. Bags are also sold through local retailers, who set their own price. The council kerbside refuse collection is contracted to Transpacific Industries Group Ltd.

In Hutt City, kerbside refuse collection is provided by the council to all urban residential properties. There is one rural collection point from which bagged refuse is collected. In Upper Hutt a collection is provided to all urban households, and there are three collection points for rural properties.

In addition to providing the council kerbside collection service, Transpacific offers a private user-pays kerbside collection service to households using wheelie bins. These wheelie bins are emptied by the same trucks at the same time as the council refuse bag collection. Other private operators, including Wheelibin Company (owned by Transpacific), Dimac Bins Ltd, and other smaller operators also offer private wheelie bin collection services.

Kerbside recycling of plastics # 1 and 2, glass bottles and jars, aluminium and steel cans, and paper and cardboard is provided to residents in Hutt City and Upper Hutt City. Hutt City Council provides households with a green recycling crate, which is collected weekly by a council contractor, AllBrite Industries Ltd (a subsidiary of Transpacific Industries Group Ltd); Upper Hutt City Council contracts AllBrite Industries to collect recyclable materials from the kerbside in plastic bags.

Hutt City Council provides five community recycling centres and one at each of the landfills. The community recycling centres are:

  • Alicetown – on Wakefield Street

  • Kelson – off State Highway 2 on Major Drive

  • Naenae – in the carpark of the Naenae Hotel, off Vogel Street and Everest Avenue

  • Waterloo – at the junction of Oxford Terrace, Knights Road and Birch Street

  • Wainuiomata – off Parkway, in the Frederick Wise Park carpark.

As well as the kerbside collections, a number of waste operators provide skip bin services to residential properties for the irregular disposal of larger quantities of refuse. Green waste collection services are also available.

S1.1.3 Waste services for the commercial sector

Businesses in the central business districts of Hutt City and Upper Hutt are provided, by their respective councils, with a twice-weekly kerbside refuse collection. Council recycling and bagged refuse collection services are provided to commercial and industrial properties outside the central business districts.

A number of private waste operators provide services to industrial, commercial and institutional properties throughout the Hutt Valley. These companies offer a range of services, including wheelie bins, drums, skip bins, huka bins and compactors.

S1.1.4 Silverstream Landfill

Silverstream Landfill is operated under a 1972 deed of agreement between the two councils, with the operation of the site being contracted to Excell Corporation Ltd. The landfill contains both a transfer station, which is used for residential loads and small commercial loads, and a landfill tipping face for large commercial loads. Both facilities are open every day of the year except Christmas Day, New Year’s Day and Good Friday. The operating hours are listed in Table S1.1, and transfer station and landfill charges are outlined in Table S1.2.

Table S1.1: Opening hours, Silverstream Landfill

Monday to Friday All year 7.30 am–5.00 pm
Saturdays New Zealand standard time 8.00 am–5.00 pm
Daylight saving time 8.00 am–6.00 pm
Sunday and public holidays New Zealand standard time 9.00 am–5.00 pm
Daylight saving time 8.00 am–6.00 pm

 

Table S1.2: Disposal charges, Silverstream Landfill

Domestic vehicles
Cars and station wagons $8.00
Vans, utilities, SUV 4-wheel drives, small trailers
(maximum refuse dimensions 2.5 m long, 1 m high, 1.5 m wide)
$15.00
Please note:
Combinations of vehicles (vans, utilities, small trucks) and trailer will cost the sum of their respective charges.
All other vehicles (per tonne) $78.00
Minimum charge $39.00
Special burials $110.00
Minimum charge $55.00
Hazardous waste
By negotiation, refer to the Hutt City Landfill: Waste Disposable Guide
Car bodies
Clean car bodies $12.00
Other car bodies $35.00
Tyres
Disposal of more than four tyres (per tonne) regardless of vehicle type $300.00
Minimum charge $150.00

All vehicles arriving at the Silverstream Landfill drive through the weighbridge kiosk. Smaller loads are not weighed, but are charged based on the size of the vehicle. Larger loads are weighed on entry and exit, and charges are based on the tonnage of the load. After leaving the weighbridge the smaller vehicles proceed directly to the transfer station for discharging their loads. Larger commercial vehicles continue to the landfill tip face.

S1.1.4.1 Transfer station

The transfer station contains three distinct areas: a green waste drop-off point, a general waste tipping pit and a recycle centre.

Charges for green waste disposal are the same as for general waste. Green waste that is disposed of at the separate drop-off point is stockpiled before being transported to the landfill for final disposal.

General waste disposed of into the tipping pit is consolidated, loaded into a truck and transported to the landfill tip face. The transfer truck contains load cells that provide a weight for each load, which is recorded manually by the driver.

Recyclable materials are not manually removed by staff from the tipping pit. However, on the way to the tipping pit all vehicles drive past a recycling centre. This area includes bins for the collection of paper and cardboard, recyclable containers and clothing. There are also separate drop-off points for batteries, oil, gas cylinders, heavy-gauge steel, whiteware, furniture, recreational and sport equipment, and household items. A large skip bin beside the tipping pit is also provided for sheet metal recycling.

Reusable items from the drop-off area are collected by Earthlink Inc. for resale at their recycling and retail store. Paper, cardboard, plastic, glass and cans are collected by AllBrite Industries for recycling.

S1.1.4.2 Landfill

The landfill tipping face is used by large commercial operators. Vehicles back up to the tipping face to off-load materials. A compactor vehicle spreads the contents of the load across the operational area of the landfill. No materials are removed from the waste stream. Large quantities of sawdust are delivered regularly from a local sawmill. These loads are disposed of free of charge and stockpiled for use as cover material.

Special waste, such as milliscreenings3 and asbestos, are disposed of to a separate area of the landfill.

A landfill methane power station operates at Silverstream Landfill. The station is owned by Mighty River Power, with Hutt City Council a minor shareholder (7 per cent).

S1.2 Data analysis and reporting

Data analysis and reporting are based on the classification and structure of waste flows shown in Figure S1.1. The diagram illustrates the four activity sources (ie, construction and demolition, industrial/commercial/institutional, landscaping and earthworks, and residential) that comprise both the waste being discharged at the transfer station and the general waste being discharged at the tip face. The combination of the transfer station waste, the general waste to tip face, the kerbside collections, cover material, and special waste together make up the overall waste to landfill.

Figure S1.1: Waste flows at Silverstream Landfill

The diagram illustrates the four activity sources (i.e. C&D, ICI, landscaping and earthworks, and residential) that comprise both the waste being discharged at the transfer station and the general waste being discharged at the tip face.  The combination of the transfer station waste, the general waste to tip face, the kerbside collections, cover material, and special wastes together make up the overall waste to landfill.

From the data collected directly by the visual survey it was possible to generate information on:

  • the proportion, by number of vehicle loads and by weight, and composition of waste from each activity source for both the transfer station and the tip face

  • the proportion, by number of vehicle loads and by weight, and composition of waste being carried by each vehicle type for both the transfer station and the tip face

  • the tonnage and composition of the general waste stream entering both the transfer station and the tip face during the survey period

  • the tonnage and composition of the overall waste stream entering the facility during the survey period.

The data analysis process started with obtaining the complete weighbridge records from the facility for the period of the audit. Initially the weighbridge data was used to obtain the net load weights of the vehicles that were surveyed at the tip face. These were used to calculate the weight of the different materials included in each load. After removal of special waste loads, kerbside collections and loads classified as cover material by the weighbridge, this data was amalgamated to provide the composition of the general waste stream disposed of at the tip face.

The data from the visual survey at the transfer station, which included estimated load weights, was used to directly determine the composition of waste disposed of at the transfer station.

Based on the classifications of waste loads used by the weighbridge, the weighbridge data for the audit period was then analysed to determine the quantities of specific identifiable waste streams, such as council kerbside collections, cleanfill, cover materials and special waste. The composition of the overall waste stream was calculated by amalgamating the compositions of the separate component waste streams in proportion to their presence in the overall waste stream.

Statistical analysis was undertaken to determine the margins of error for waste disposed of at the transfer station and general waste disposed of at the tip face. By contrast, it was not possible to determine confidence intervals for the overall waste stream because its composition is based on the weighbridge records.

1 Department of Statistics ANZSIC codes, 2002 figures.

2 Waste Not Consulting, Wellington ‘Waste Catchment Trial’, 2006, unpublished report for the Ministry for the Environment.

3 Milliscreenings: fine solid particles, generally inorganic, that are screened from wastewater as part of the initial treatment at a wastewater treatment plant.