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  Riverford sustainable development project



April 2009 - Compost!
Ridan composter

A few weeks ago we took delivery of a new piece of composting kit produced by some friends of ours up on Exmoor.  Composting is a natural process that converts organic material (plants etc…) into a product that can be used to build soil fertility and encourage a healthy living soil in the long term.  It is also a way of reducing the volume of organic waste and producing a useful output rather than simply throwing it ‘away’.


At Riverford our veg peelings go to the farm compost heap, along with cow manure which, once turned over and matured for 3 to 6 months we spread on our land to improve its fertility. 


We can’t send cooked food to an open heap due to concerns about attracting pests (such as rats) and potentially spreading disease amongst wildlife.


The field kitchen and the staff canteen together produce almost 5 tonnes of cooked food waste each year, which if sent to landfill would be responsible for the same carbon emissions as the average car in the UK


To prevent these emissions and to return nutrients back to our soil, we are now composting our cooked food waste in a two stage process; first in the ‘Ridan composter’ and then in a worm compost bin.  After a few weeks we will end up with good quality compost which we can use to improve the fertility of our trial plots. 


Over the coming weeks we will be setting up a selection of composting equipment to form a demonstration area, showing different ways of composting for schools, businesses and householders alike.  Feel free to come and have a look if you are in the area!


If you are interested in a Ridan composter for your school or business please contact Dan Welburn on 01598 740075 or 07901 675938.  Alternatively have a look at www.ridan.co.uk



From 6th October 2008 we will be asking customers to return all the plastic bags that we use for vegetables to us for recycling.


Here is why (the science bit)


If you're too impatient to read this see our FAQs section

The packaging we specify is important for a number of reasons, it obviously must protect produce, it serves a communication function and it has an environmental impact both in its production and disposal.


In the UK 25% of household rubbish (i.e. going to landfill) is retail packaging; this is reflected in public perception of packaging as being an important issue that companies should deal with.


Like most environmentally motivated questions there is no straight answer to which packaging materials are ‘best’.  Studies known as life cycle assessments (LCA) can be carried out to determine which is best.  What impacts are measured varies widely with different studies however.  Whether or not disposal or just production impacts are measured also varies depending on the context, how much time there is to spend carrying out an assessment and, often, who is funding the study.  Unsurprisingly, studies funded by paper bag manufacturers often conclude that paper bags are better for the environment than plastic, and vice versa.


We have reviewed research into the different types of plastics available and the environmental impacts that come with them, based on this work we have decided to switch from the current degradable bags to conventional plastic which we will collect from our customers and recycle.


The plastic bags Riverford use at the moment are a conventional plastic (LDPE or polythene) with an additive that causes them to break down under exposure to sunlight, air and stress.  This is called an oxo-degradable plastic.


The energy used to make these bags is pretty similar to that for a normal polythene bag, so the environmental impact is pretty similar.  There is no impact during the life of the bag, except a bit of transport and this will be the same for all types of plastic bags.

The difference is what happens once the bags have been used.

Our current bags cannot be composted at home or industrially.  Even if they could, composters are not keen to take bags that look just like normal plastic as they would have to check each one.  The bags can’t be recycled either as they would damage whatever was made from the recycled plastic by breaking down.

This means once our customers are finished with the bags they have only one choice; sending them to landfill.  Once in a landfill site the bags will begin to break down, generating greenhouse gasses carbon dioxide (CO2) and methane (CH4).  Methane is 23 times more powerful than CO2 as a greenhouse gas and so in many landfill sites it is captured and used to generate energy, however in some it still simply leaks into the atmosphere contributing to global warming.


Normally a plastic bag would go in the bin, to a landfill site, and then sit there for hundreds of years, slowly breaking down.  So even this is doing less damage than what we are doing at the moment.


Biodegradable plastic bags are available that could be composted.  These, however, take similar energy to make to a conventional bag (sometimes much more) and cannot be recycled.  All the energy that goes in to making bags in the first place is then lost, whereas recycling reclaims some of that energy by not having to extract new materials.

A better system would be to use normal plastic bags, taking them back and recycling them, meaning less non-renewable resources are needed and less energy is used in producing plastics (less is needed to recycle than to extract from crude oil).  Most plastic bags don’t get recycled as it is not financially viable to do so.  We, however, are in a position to do this: our weekly deliveries and well established transport system (and our environmentally motivated customers) make recycling viable.


This is exactly what we plan to do as of October 6th, asking our customers to send back the 27 tonnes of plastic bags we send out to them so we can take responsibility for recycling them.  Based on recent government studies on recycling this would save up to 100 tonnes of CO2 a year, as well as significantly reducing landfill emissions.  This is the same as taking about 30 cars off the road every year.


For more on our packaging generally click here.


For more on what we recycle and what to do with the packaging we send you click here.


In March this year we started calculating the CO2 efficiency of our fruit and vegetable sourcing on a weekly basis, full details of this can be found here.  We found the tool useful in deciding where to buy from if there were a number of options; shipping produce from Morocco turned out to be much better than trucking in from Southern Spain.  This information has also begun to guide our long term policy.


The source to Riverford transport CO2 emissions calculator is useful for 2 reasons –


1) most importantly, it allows us to source our fruit and veg in a more carbon-efficient way, working with our suppliers to reduce our environmental impact up the supply chain as well as here at the farm. 


2) we believe in choice, variety and that customers should have the opportunity to buy global produce once we have sourced in the most carbon efficient way we can, we report the figures to our customers so they can choose a veg box with the lowest carbon emissions if they want to.


Take time to look at the packaging on any food product you pick up in the supermarket and you will be overwhelmed with information, brand, source, organic or not, calories, fat content… and sometimes even CO2 emissions.  You can either ignore all of this information (as I am sure most people do) or try to use it to make a decision, which means something to compare whatever-it-is to. 


We deliberated long and hard about whether or not to report our sourcing CO2 emissions to customers, and how we should do it if we did.  I believe that what we developed is a useful scale, allowing customers to compare different boxes of veg on a CO2 basis if they so wish.


Previously we have not included the fruit box as there is no real choice to be made on the customer’s part; we only sell one fruit box and a lot of the fruit has to be imported from abroad.  We go to great efforts to import in the most carbon efficient way, using shipping where possible and there is really little else for the customer to do. 


As the fruit box can now be ordered as a stand alone box we will begin to report the sourcing CO2 emissions for uniformity across the board.  As most of the time it will consist of a lot of imported produce the emissions will be high in comparison to the other core boxes, this is simply a fact of life due to the constraints of our climate, you will simply have to invest your faith in us doing things as best can be done.  I am concerned however, that ever more information will bamboozle customers so please let us know if this is going a step too far in the interests of uniformity rather than helping you, the customer, make a decision on your box.


Leaving your veg box exposed to the elements if you're out all day can do the veg no good at all, we have created a low cost, low energy solution to this problem.


See our new section 'cool veg' to find out more!