Traffic (Operational Phase)

 

Monitoring

Monitoring the impact of aggregate transport should be carried out through regular environmental audits and spot checks, to ensure compliance with conditions laid down by the MPAs is being achieved. This must apply to vehicles operated by the quarry operator and by sub-contractors, to ensure they operate with minimal impact upon the environment and upon the communities along the routes.

With the rise in concern over carbon emissions, monitoring of fuel usage has become increasingly important. The continuing rise in fuel prices means that it is in everyone's interest to manage fuel usage, which require it to be measured and monitored.

Work to quantify carbon emissions and the savings made through changing practices has progressed in recent years. The Fleet Performance Management Tool L0373 is a spreadsheet available free from Freight Best Practice L0372 which allows the user to input basic vehicle operations data and obtain Key Performance Indicators allowing internal/external benchmarking for a fleet of up to 25 trucks. The tool reports truck mpg and outputs CO2 emissions for each vehicle and the fleet. It claims to deliver real cost savings of between 3% & 4%.

WRAP's Aggregain website has a CO2 emissions estimator tool L0374, which allows the user to calculate CO2 quantities of different aggregates supply options for a construction project, based on transport mode as well as other parameters.

WRAP (Waste and Resources Action Programme) has also developed a number of Aggregates Life Cycle Assessment Resources L0375; five calculator tools, including a Product Distribution Tool. The model allows for consideration of the impacts associated with the extraction and processing of primary resources through to the point of despatch as aggregates. Forms are also available to help with the considerable amount of data collection required.

Good Practice

A number of resources are available which should be read in conjunction with this section. Freight Best Practice L0372 is funded by the Department for Transport and managed by AECOM to promote operational efficiency within freight operations. The Transports' Friend L0328 website gives a very useful summary of the resources and assistance available to freight operators.

Before considering what can be done when road haulage is unavoidable, some of the possible alternatives will first be considered. There are two main reasons for this; the reduction of local impacts (noise, congestion, dust, etc.) and the reduction of CO2 emissions. Although often unavoidable, road transport of aggregate produces considerably more CO2 per tonne per kilometre than rail or water (160g CO2/t/km, cf. 41g and 25g respectively).

Alternatives to Road Haulage

One question which should be addressed is whether road traffic can be avoided in sensitive areas by using alternative modes of transport or by routeing it where its effects are more acceptable. Some authorities have presumptions against haul-routes using public roads between the excavation and processing plant and the use of significant lengths of local roads to gain access to the major road network. They encourage the use of conveyors (Photograph 5) from the excavation to the plant, a railhead (Photograph 6) or, to a lesser extent, a quay as means of distribution by ship (Photograph 7) or barge (Photograph 8) 86. An ALSF project L0074 looked at alternative approaches to the transport of aggregates from a carbon reduction point of view. Case studies considered the use of barges on the River Severn, the Mendip rail joint venture and a multimodal aggregate transfer operation C0012 C0013..

Photograph 5. Distribution by conveyor, also routed through tunnel.		Photograph 6. Wagon set for distribution by rail.

 

Photograph 7. Distribution by ship from coastal quarry.		Photograph 8. Distribution by barge.

 

During the past few years conveyor techniques and technologies have been developed for application in the quarrying and mining industry 256, although this is mostly for use within the site. These include the advent of curved and high angle conveyors which means they can now be considered for situations in which they were previously unsuitable. Field conveyors (Photograph 9) are more likely to be viable and those capable of ascending steep slopes would reduce the need for long haul-roads and the use of dump trucks.
		Photograph 9. Field conveyor.

 

A greater use of pipelines to transport sand and gravel may be possible. Pipelines are already used where suction-dredging is employed as the means of extraction, and for the extraction and transport of china clay. In other cases the use of slurry pipelines and aerial ropeways seem to have limited or no application.

In discussing the possibility of alternatives to road haulage, it must not be forgotten that they in turn will have environmental issues of their own. Caution must be exercised to ensure that problems are avoided at the receiving end of any link. Except for some coal delivered to power stations, nearly all minerals are transferred to their final delivery point by road.

Perhaps the biggest difficulty in achieving improvement in the haulage of aggregates is the sensitivity of the selling price of the mineral to transport costs. Haulage can represent half the price after a journey of about 30 miles. The situation is less problematic for the higher value aggregates and minerals, or where economies of scale make it economically feasible to transport the mineral for long distances, e.g. granite from Scotland to the south-east of England by sea.

The ALSF Review on Transport L0073 states clearly that a modal shift from road to rail or waterways reduces the carbon emissions produced by transporting aggregate. The Department for Transport has run a number of schemes which have supported this shift. The Freight Facilities Grant (providing capital support for essential equipment and facilities) was closed in January 2011, but the Mode Shift Revenue Support Scheme (MSRS L0377) and the Waterborne Freight Grant for coastal waters (WFG L0378) are still in operation at the time of writing. The MSRS is a direct replacement for both the Rail Environmental Benefit Procurement Scheme (REPS) and the Waterborne Freight Grant for inland waterways.

The grants are awarded based on a full calculation of economic and environmental benefits. The calculation is based on the Sensitive Lorry Miles methodology which attributes different levels of quantified and monetised benefits from removing lorry journeys from different types of road. A range of benefits are identified with the highest value put on relieving congestion. An online calculator of environmental benefit values for use by applicants to calculate the value of a route is available available from the Department for Transport's Transportdirect.info website L0376.

Although it does not reduce the tonnage being carried on the roads, one way of reducing the number of vehicle movements is to use large capacity articulated tippers, which can carry between 25% and 50% more material than rigid tippers. The Case Study document "Reducing Costs and Improving Efficiency with Articulated Tippers" C0059 includes two case studies: one reviewing a large operator (Lafarge Aggregates); and the other a medium sized operator (K&J Contractors). The study illustrates how both operators have experienced substantial savings by reviewing the composition of their fleet.

 

Continued with Good Practice Continued.

TOP

Return to Control of Transport Impacts.