I received this call just this past month. A local contractor used to dispose of materials at a yard waste facility. The site never really ground any materials or screened any for that matter, rather, they just collected tipping fees and piled up materials for several years. This is not uncommon. There are probably hundreds or thousands of these sites around the Country. Mining “Stump Dumps” would be the same philosophy.
One of the first questions I was asked was “What equipment do I buy?” Nothing was my answer. Rent equipment to clean up the facility and then see what the majority of new incoming materials are received and make your buying decisions from there. Machines like Trommel Screens can be rented by the week if necessary.
So how would one go about cleaning up a facility such as this?
· Initially, determine the amount of contamination in the materials and piles. Plastic, concrete, rock and dirt limit how these piles can be reduced and reused.
· If these piles are too contaminated, too great a cost could be expended limiting the profitability of the operation
· Decide what equipment is best to get some initial separation and reduction
· Separate materials into like kind. Fines, logs, brush, etc.
· Determine what markets the majority of materials can be sold in and the price of the finished product.
These piles that have been sitting for a year or more usually have a lot of dirt and compost in them. Screening out the dirt and compost can turn income dollars quickly. But what do you screen these piles with?
· If the piles are relatively clean of bigger rock and concrete, a trommel screen will work just fine.
· If there is big rock and concrete some type of disc screen or screen with a vibrating grizzly is the best alternative.
· If these piles are full of largely uncomposted brush, a wheel loader with a rake is the best way to separate fines from brush quickly.
· It is easy to separate large logs and stumps from pile that are mostly composted with an excavator and grapple
When new materials start coming in, separate each material by type:
· Logs and stumps
· Grass and leaves
Materials like chips, grass and leaves do not necessarily need to be ground up and reduced. Logs and brush do need to be reduced. Subcontract grinding services until the costs to do so are more than owning your own grinder or shredder. This may take several years, especially if you are separating materials and not grinding materials that do not necessarily need to be ground up.
Materials like logs and chips can be turned into mulch and sold quickly without waiting for the compost process. Blending old wood with new wood makes a consistent product and not dark one day and light the next.
When it comes to screening, it is easy to pile up a few thousand yards and then rent a screen and screen everything in a month or so, saving the cost of purchase.
So, in conclusion:
· Rent as much as possible to get a start on cleanup
· Separate materials
· Turn easiest to convert product into dollars quickly
· Subcontract grinding as much as possible
· Keep new materials separated and turn the ones that are easily converted into dollars quickly
Dave Whitelaw- Grinder Guy