SMRUK will save you money by helping you divert spoil going to landfill.
Updated: Sep 7, 2020
In 2017 we joined forces with Balfour Beatty, in alliance with Anglian Water, who were undertaking a new £1.8 million scheme to reduce the chance of bursts and leaks in the Framingham area of Norfolk by replacing existing water mains.
The project phase involved laying over 11km of new water mains along the B1332 Shotesham Road, just south of Norwich, including other local areas of Bixley, Framingham Earl, Caistor St Edmunds and Porlingland.
What made this project ground breaking is that Balfour Beatty recycled all the excavated spoil material. This was done by treating it with SMR, the dry mix soil stabilisation additive was provided by Richardson Recycling and SMR (UK) Ltd, then re-using it as an alternative sub-base material, diverting all the trench arisings from landfill.
The Process:
The material from the trench excavations is collected by grab lorry and taken to Richardson Recycling’s local facility on a ‘tip & take’ basis. Here the spoil is screened to remove organic material and solids over 40mm in diameter, before being mixed with the SMR soil stabilisation powder. The resulting material is then returned to site by grab lorry where it is used as trench backfill and compacted in layers. The physical transformation is that under compaction the treated material adheres to the trench wall causing no shrinkage; stabilising the backfill which results in no block or beam effect.
Chris Taylor, Construction Manager with Balfour Beatty who heads up the project comments: “On this project we had two priorities: Firstly reducing the carbon footprint of the job and being as sustainable as possibly. Secondly, on a high profile project such as this we could not risk any backfill shrinkage which would have affected the reinstatement, meaning future remedial works and returns to site could be required. Our policy is to get it right first time. With such a large project, recycling as much of the material coming out of the ground as possible makes good economic and environmental sense. As part of Anglian Water’s @One Alliance team, we are looking to expand the use of SMR across all our projects. It is not just the sustainability angle that is attractive, SMR produces an exceptional product that is stable and compacts well, as well as returning a substantial saving on material costs.”
The savings both finical & environmental :
In circumstances that use traditional Type 1 sub-base material, all excavated spoil would have gone to landfill. The nearest depot to the Framingham project was the Cemex Flixton Park Quarry & Recycling facility near Bungay, a 25 miles round trip away. Regardless of the financial savings made avoiding landfill, the Co² improvement on the project alone was quite startling.
The trench excavation was 600mm wide by 1100mm deep and 11 km long, equating to 7,260 m³ of material, which equals 10,164 tonnes. Transported by a fleet of 8m³ lorries, this would have equated to 907 vehicle movements. With each movement being 40 km, the overall distance travelled would have been 36,300 km, resulting in a carbon rating of 97,284 Co²/kg all removed from this phase of the project, by using SMR as sub-base backfill thereby reducing the carbon footprint.
Cost comparisons on Type 1 and 2 roads, per 1000 metres for materials and tipping fees were calculated as follows:
Please see above graph to see a visual representation of the true saving of using SMR.
On the 11 km of trenches excavated for the new Framingham Earl water main, material savings of approximately £250,735 were made simply by adjusting the reinstatement specification. The SMR sub-base was layered to a depth of 650mm, as opposed to 465mm of MOT Type 1, thus reducing the thickness of both the asphalt base and wearing courses, resulting in a 40% overall saving in material costs.
The benefits of using SMR over conventional backfill are as follows:
Removal of landfill: All excavated material is re-used on site with the binder and arisings remixed into recycled fill material. The result is zero material being sent to landfill, with no tipping fees and no associated transportation costs.
Reduction of quarried aggregates: With no imported primary aggregates being used on this project, reducing dependency on imported materials and utilising materials on site.
Reduction of Carbon Footprint: By sending excavated material to be repurposed as SMR backfill the number of vehicle material movements is halved.
Cost savings: The cost savings are clear, no land fill fees and a 50% reduction on transportation costs.
No shrinkage or defects.
A large reduction in the number of grab lorry movements.
Ease of working and a quicker project time.
“In April 2017, the UK landfill tax increased to a standard rate of £86.10 per tonne with an inert rate of £2.70 per tonne,” comments Andy Bareham, Technical Support Manager for SMR (UK) Ltd. “The actual cost of non-hazardous soil disposal also varies across the country, typically costing around £20 to £50 a tonne, with the cost of contaminated soil disposal being significantly higher. Transport costs further push the cost of disposing of waste material and with heavy diesel transport operators being increasingly penalised for inner city movements, reusing materials where they were excavated makes sound environmental sense.”
UPDATE: As of April 2020 the UK landfill tax has increased even more & the standard rate now is £94.15 per tonne with an inert rate of £3.00 per tonne, this is very likely to increase in April 2021.
SMR (UK) is significantly increasing the number of locations around the UK where the technology is available to blend the SMR additive with excavated spoil, by growing its national network of recycling ‘HUB’ partners. Each ‘HUB’ has the necessary mobile screeners, Batch-Mix equipment and specially formulated additive, enabling them to offer their customers ready mixed and recycled sub-base from the excavated spoil.
For more information on the SMR soil stabiliser process or to find out the benefits of joining the growing national network of recycling ‘HUB’ partners either call 01252 710772 or visit www.smruk.com