Civil Engineering July 2021 | Vol 29 No 6

Civil Engineering July 2021 45 I ndustry updates S urface mining industry association ASPASA has worked with the Committee of Transport Officials (COTO) and role-players to hammer out standards for different types of materials to be used on our roads. Crushed aggre- gates and sand are key components in the manufacture of this type of infrastructure and the new COTO specification effec- tively replaces the previous, widely-known COLTO specification. Industry veteran and the motivating force behind ASPASA’s submission to COTO, Barry Pearce, who heads up ASPASA’s technical committee, says the new specifications have brought the industry together like never before and led to close cooperation between roads agencies, engineers, materials suppliers and road contractors. Material suppliers will now have a two-year trial period to implement, test, debate and refine the specifications before final acceptance. SIMPLE IMPLEMENTATION “Now all that remains is for our ASPASA members to read the specification in its entirety, especially Chapter 4 which deals directly with the supply of materials. The move from the COLTO to COTO specifications also comes with a change in sieve sizes from imperial to metric ISO sizes. That means quarries will need to make minor changes or possibly set about changing worn grizzlies and screens to match the relevant COTO sizes so as to conform to the new specification,” says Barry. “The specifications also pay closer attention to the testing and acceptance of materials where they are mined and upon delivery and usage. ASPASA has long been of the opinion that acceptance needs to be conducted at the source of the material and before any further processing such as the addition of cement or binders take place. “For now, this method of acceptance is required for materials sourced from approved borrow pits and requires engineers to test and accept crushed and stockpiled material at the borrow pit before delivery to site and further pro- cessing by the contractor. Our technical committee, however, suggests the same should apply to existing quarries with some minor adjustments where compli- ance with existing legislation is already in place, such as HSE requirements. If this approach of approval of material is adopted, I think the COTO specification will be as near to ‘perfect’ as we can get it right now,” continues Barry. EXCLUSION CLAUSES He adds that onsite acceptance testing at the quarries will leapfrog one of the biggest hurdles in the supply of materials, namely exclusion clauses. These are used by material suppliers as a measure of protection to ensure slight variances in quality of materials, as specified, are accounted for and can be excluded from the overarching specification as well as protection from claims where the material has been further processed on site by the contractor. In other words, a clearer differentiation in where the material responsibility is passed to the contractor and the supplier is no longer responsible. Nonetheless, despite not being a requirement of the new COTO specifica- tions, these and other sticking points should be ironed-out by the supplier and the engineers, road builders and transport agencies before any project is started. ASPASA members are always encour- aged to ensure the contractual work of specifying, onsite and laboratory testing, processes of delivery, and onsite accept- ance methods are agreed upon upfront and are legally documented to prevent issues arising into the future. Ongoing work “ASPASA and our technical committees will continue to work with the agencies, Road Pavement Forum, South African Bitumen Association and other role- players to ensure COTO specifications are upheld and that our members are well- versed in the supply of in-spec materials. We will also continue to highlight any issues that may arise in the two-year im- plementation period,” concludes Barry.  Newmaterial specifications for road builders Quarrymen and miners of materials used in the construction of roads have a new set of specifications to be followed in order to supply national and provincial roads agencies as well as all metros and municipalities.