Decision-Making Guide Overview
This guide has been produced to provide you and your community with information that should assist you to understand how to develop a successful composting project.
There are 7 steps that cover many of the opportunities and issues to be considered.
You can either click on step 1 below or go directly to the steps of interest:
- Step 1 of 7: What can be composted?
- Step 2 of 7: How much waste do you want to manage?
- Step 3 of 7: Who could be involved?
- Step 4 of 7: Methods and technologies for making compost
- Step 5 of 7: Safe and beneficial use of compost
- Step 6 of 7: How much do community composting projects cost?
- Step 7 of 7 : Summary of the key points for community composting
Step 1: What can be composted?
Overview
You can make compost using different waste streams:
- Garden waste (including some brown wastes)
- Food waste – kitchen and canteen waste (with and without animal by-products)
- Other brown waste (shredded paper, card, etc)
- A mixture of garden, food and other brown waste
Each of the above provides you with the potential for a nutrient rich growing medium and soil conditioner which can be used by your community group as a local resource for local growing projects or use by individual householders.
If you are a householder you can compost any of the above wastes in your own garden. If you have an allotment on land owned by the council or other, you need to check the rules that are in place. If you are a community project there are regulatory requirements you need to follow which are set out in the Quick Guide to Regulations and Guidance for different waste streams.
Garden waste
Garden waste can be any cuttings from individual household gardens or from other public and private areas, such as roadside verges, parks and estates. If coming from public or private areas your community will need permission from the landowners to use these. You should also be careful to not include invasive weeds (such as: Japanese knotweed, giant hogweed, Himalayan balsam, rhododendron ponticum and New Zealand pygmyweed). Garden waste is the simplest ingredient for making compost, and it is important to include a mixture of green and brown waste as explained below:
- Green waste – consists of grass, straw, hay, leaves, trimmings from perennials and annuals, as well as annual weeds that haven’t set seed.
- Brown waste – means tree and shrub prunings (finely chopped), as well as shredded paper/card (see more on this below – “other brown waste”).
Straw referred to above should be clean and not previously used for animal bedding.
Food waste
Food waste with animal by-products refers to meat, eggs, egg shells, fish, shell fish or oil used for cooking these. Animal by-products are a potential source of risk to human and animal health and as such require specific, additional considerations.
Food waste without animal by-products refers to vegetable and/or fruit waste, which includes peelings, left-overs, or fruit and vegetables no longer suitable for consumption.
If you only collect fruit and vegetable waste for composting and do not take food waste containing meat or other animal by-products then your project will not need to be regulated by the Animal & Plant Health Agency (APHA). If you do want to take such waste then you need to go through a checklist to understand if your project does need APHA approval and ongoing monitoring. See the Quick Guide to Regulations and Guidance for more information.
A reason for avoiding animal by-products such as meat is that it is likely to attract vermin to your site and might also add to the cost of your project. The cost implication depends on how much food waste (containing animal by-products) you collect, where it is stored and where the compost you produce will be used. These factors significantly influence the score you achieve when you go through the checklist above.
Food waste consisting of only vegetable and fruit waste is therefore much less onerous to collect and compost. However, it must be composted in a closed container i.e. you cannot do this in an open pile. In terms of closed containers you can build your own box or boxes, or buy composters from a range of organisations. More information is provided on these in the Technology & Method section of this guide. If you decide to compost food waste with animal by-products this must also be in an enclosed container.
Small-scale projects (even those including the composting of meat) are most likely to have little or no costs for complying with regulations. It is important therefore that the design of your project considers the regulatory requirements which are described in more detail if you go to the Quick Guide to Regulations and Guidance page.
Other brown waste
You can use shredded paper and card, as well as wood shavings/sawdust (no chemicals added) for composting, e.g. as a substitute for tree and shrub prunings etc mentioned above.
If possible you should consider if it might be best to put these paper/card into local recycling bins for collection. If your site needs this material you should be careful to manage it to avoid staples and tape getting into the mix.
If shredded paper/card is used in an open pile with garden waste it could make up a significant part of the mix, or if used with a container/bin it can be much higher, as explained in Step 4. Most of the time, it is recommended that you use untreated paper for your compost. If the paper is covered with heavy or potentially-toxic inks, for example from a printer, or it is coloured paper, it should not be composted and put to a recycling container instead.
Mixed garden/brown and food waste
It should be noted that if you mix food waste with garden/brown waste the rules/regulations applied to food waste apply to the whole compost pile.
Click on Next Step below – how much waste do you want to manageTo
Step 2: How much waste do you want to manage?
Guidance on planning and calculating how much waste to manage
You may be considering the potential to compost waste from the following sources:
Garden waste from:
- Households or
- Local organisations, businesses, education facilities
Food/canteen waste from:
- Homes or offices
- Restaurants
- Caterers
On a practical level it is useful to be able to calculate the volume of compost you will be handling in order to size the space required for composting and ensure you purchase the right size of system/equipment. The document below show you how to to calculate the volume of compost on the basis of the weight of the waste you are likely to collect:
Food and garden waste from households
Data from two rural Scottish local authorities has shown that the quantity of food waste set out by households participating in weekly kerbside collections ranged from between 2 and 2.4 Kg per week. This translates to between 104 and 125 Kg per household per year. For your community composting project this then provides a way of estimating what could potentially be sourced locally from participating households in your community and allows you to plan how large you want your project to be.
If you are planning to use food waste in your compost pile (e.g. with garden waste, paper etc) it is recommended that you keep the compost output to less than 10 tonnes per year as this reduces regulatory requirements as explained in the Quick Guide to Regulations and Guidance for different waste streams. If you do this you will avoid the associated costs and complexity, as explained in the guide.
To keep to below the 10-tonne level, the following example, for planning the number of potential households is provided as an illustration, for a scenario where food waste and garden waste are being mixed:
- 20 households providing 2.4 Kg per week of food waste will amount to 2.5 tonnes over a year (52 weeks). Mixed with another 7.5 tonnes of garden waste (3:1 ratio) gives an initial input of 10 tonnes. This could in turn biodegrade to around 7.5 tonnes of compost (25% weight reduction).
- 27 households would provide 3.4 tonnes of food waste, which when mixed with 10 tonnes of garden waste (3:1 ratio) would give an initial pile of 13.5 tonnes which could then degrade to 10 tonnes (25% weight reduction).
Roughly speaking a good mix is to have around 3 to 4 times as much brown waste as greens in your mixture. Generally, the browns (garden waste, paper/card) provide the carbon and the greens the nitrogen needed for a good quality compost.
Because garden waste will be generated mostly in the growing season storage will be required, allowing you to add to the food waste throughout the year (if desired), unless the system being used would include wood chip, paper etc.
Food and garden waste from other sources
Although most businesses in the Highland Region (outside of Inverness) do not have a legal duty to make food waste available for separate collection, many do want to make this waste stream available for more sustainable, environmentally friendly and local purposes, and could be a useful source for your community project. Hotels, schools, restaurants and cafes can generate significant quantities of both garden and food waste, and in some locations will generate significantly larger quantities than the surrounding households.
Click on Next Step below – Who could be involved
Click to go back to the Decision-Making Guide overview
Step 3: Who could be involved?
The following could be involved:
There are many different models of community growing and composting across Scotland, the rest of the UK and internationally. Some of the more common initiatives are detailed below.
Community Growing Projects, Gardens/Allotments
This type of composting scheme is typically volunteer-led, although volunteers may opt to form a constituted Community Interest Company (CIC). It involves the coming together of interested people to compost collectively, rather than individually on their own plot.
Some allotment/ community schemes restrict access to allotment plot holders, however many enable local residents to take part through offering memberships. Sometimes, the community garden/ allotment also offers educational opportunities for local residents or provides opportunities for residents to obtain or purchase compost if there is an excess.
An example is the Bilsley Community Composting Scheme which has been in operation since 2005. Residents pay £30 annually to become a member. The scheme is managed by volunteers with help from some paid local labour. Once composted, the product is offered back to their members and allotment holders. The scheme reports that it has strong links with the local council, with a councillor for example sitting on their board. Forging close links with the council has enabled the group to successfully apply for small-scale funding. Further information on this scheme is available here.
School Composting
Schools engage with community composting for many reasons, some wish to reduce food waste from school kitchens or produce their own compost for the school garden, others take the opportunity to use composting as an additional way to engage with their wider community. Archbishop Ilsley Catholic Technology and Sixth Form Centre, Birmingham collects uncooked food waste from the school kitchen and transports it to a local allotment where family members are actively encouraged to participate in the composting process.
Depending on the complexity of the project, the school composting schemes may form close relationships with local businesses, the council or the parent teacher association.
Drop-Off Networks
These are typically managed by a community group or small environmental charity. One or more ‘drop-off’ locations are set up within a local area. The composting site may be located within a green space, a park or church grounds. It is important to ensure that there is an end-use for the compost if the composting scheme is not linked to an allotment or food growing project.
Some projects ask users of the scheme to volunteer a nominal number of hours to support the scheme. The type of technology will influence the type of material that can be accepted on site.
A well established example of a drop-off network could be illustrated by the “worm hotels” established within Amsterdam. There are 200 in operation, each serving approximately 30 households (with a waiting list at the time of writing for 300 more). Key partners involved in the worm hotel project include the local authority who provides financial support, a social enterprise providing supported work which provides the wormeries and a range of private partners.
Collection Schemes
There are several examples of case studies which involve the collection of food waste through the use of horses or bikes. This type of project is more difficult and time consuming to set up, although has the added benefit that all residents can take part.
Potential Collaboration Opportunities
It is important to consider what you would like to achieve when thinking about potential partnerships that could be formed. An example of a successful partnership is detailed below to illustrate the types of organisations that could be involved in a community composting scheme.
The Brighton & Hove Food Partnership, the Council, residents, and volunteers collaborate together to successfully run a community composting scheme. The Council provides the Food Partnership with funding to manage the scheme, the funding pays for compost caddies, two part-time paid members of staff and an external maintenance person. The Food Partnership co-ordinate the 40+ schemes, they provide support to the local community groups, the council and residents and act as a central point of contact. Each scheme has two volunteer compost monitors, who are responsible for overseeing their local scheme. Compost monitors induct new members to their scheme and update the waiting list, turn the compost, check for general maintenance, and liaise with the Food Partnership about any issues they are having. Residents are those who are members of the compost scheme. Residents will drop off their food waste at the bins and turn the compost. The detailed case study on this project is available here.
Click Next Step below – Technologies and methods for making the compost
Click to go back to the Decision-Making Guide Overview
Step 4: Technologies and methods
Small scale options for making your compost
Overview
Making compost in a community project does not need to involve complicated technology or excessive costs. There are in effect three options for your community composting project:
Composting in piles: for garden waste and paper/card – note that food/canteen waste cannot be composted this way in a community project.
Composting in containers or vessels: sometimes referred to as “in vessel composting” (IVC). The use of containers is required by the regulators, SEPA and the APHA, for kitchen/canteen waste (with or without meat)
Wormeries: Worms can eat about half their body weight in food waste in one day, turning kitchen and garden waste (excluding meat) into nutrient-rich compost and a liquid fertiliser called worm tea.
Regardless of which option you decide to go for, it is useful to have separate areas for brown and green garden waste as this will help when mixing (described below). Other organisations have provided detailed guidance on how to set up and arrange a composting site, such as Social Farms and Gardens (Page 36 of the guide).
Layout of Your Site
In terms of layout the Legislation guide has a link to SEPA’s form, Paragraph 12 Exemption – Composting. This form says that if your project involves having more than 10 tonnes of material (food and/or garden waste, compost) on your site at any one time, a plan will be needed. This should show the site boundary and where different activities are taking place. It should also show the locations of any buildings, public right of ways, groundwater abstraction points or surface waters situated within 250 metres of the site boundary. You should plan your site, regardless of how much waste is being managed, to keep water (that has percolated through the waste or compost – leachate) from running off site into surface water (rivers, streams etc) and food growing areas. More information on how to consider this for your project is available in the guide “Community Composting Done Right – A Guide to Best Management Practices.”
SEPA will probably not get involved with your plan/layout as it is the community group’s way of making sure that the risks from the process have been identified. The group might also use the layout/plan to think about how to prevent vermin problems and mitigate against dust and odour generation/emissions.
Composting in piles
This is the simplest and least expensive composting option. It only needs a suitable area of land where the garden waste and paper/card can be brought and then managed (note that food/canteen waste cannot be composted in open piles).
There are many examples online of how composting piles can be organised and there are many ways to produce a good quality compost. The following steps are presented for illustration only, as one example of what you could do:
- Shred any large branches so that it looks more like a wood chip material, where possible – having some larger branches in the pile will not do any harm. You may be able to hire a wood chipper, or you can buy one that is sized to meet your needs.
- If you can, try to arrange the browns and greens into a 3 or 4 to 1 ratio (by weight) to make sure that you get a good carbon to nitrogen mixture.
- Add the browns and greens in layers (e.g. around 30 centimetres thick) until you have a pile around 1 metre high.
- Mix your pile or piles using a fork/shovel or other equipment on site, to allow air and moisture to be present as uniformly as possible throughout the pile – this will prevent it from becoming smelly (anaerobic, due to a lack of oxygen), increase the temperature of the pile and speed up the composting process.
You can create good quality compost with one pile, but if you have more than one you can then rotate these i.e. one or more that is actively composting and another(s) that is/are mature and ready for use.
Composting in containers/vessels
There are different levels of complexity when it comes to composting in containers or vessels:
- Wooden boxes with lids.
- Insulated bins or boxes, currently available in plastic and available for purchase.
- Vessels that rotate and use electricity to add heat
In the Compost Works project in Liverpool, a small number of households drop off their food waste (vegetable and fruit peelings only) in wooden boxes made by the Compost Works team. Compost is available 9 to 12 months after this. The Brighton & Hove Food Partnership is a food growing, redistribution and community composting project, currently delivering very successful projects – a specification for the wooden composting box bins is available at their website here.
If you are composting kitchen and canteen food waste, this has to be in containers with no gaps. Because these do not have an open base in direct contact with the ground this will minimise access from vermin.
It should be noted that the more insulated your box, the faster the pile will reach the temperatures needed for effective composting and the better it will retain the heat. However, these bins also have to allow air in/out of the pile for the waste to decompose properly. You can design this into your own composting unit, or buy insulated composting bins from a range of companies, as listed here. These can compost food, garden and paper/card and include electrically powered vessels that rotate and add heat to the pile.
If one of your aims is primarily to compost food waste, depending on the system, you will need to add wood chip (to keep the pile aerated) or paper/card, with manual mixing, to keep the pile operating effectively. Some of the suppliers provide guidance on how much of each waste type should be added.
More information with examples of the above containers and vessels can be obtained from the Case Studies page.
For readers interested in more technical details, a guide has been produced by the European Union on “Community Composting: A Practical Guide for Local Management of Biowaste Technologies and Methods“.
Zero Waste Scotland has also produced a guidance webpage on how to compost food and garden waste. This is aimed at projects which are likely to be operating at a larger scale than a community composting project, but the information still has some relevance to smaller-scale projects.
Wormeries
Although these can be used for food and garden waste they are often used in projects as a way of demonstrating how food waste can be turned into a valuable nutrient for soils,
The approach can involve starting off with worms in some soil, with kitchen waste added (no meat, avoid citrus fruits and large volumes of onions), plus brown waste (e.g. newspaper or card), in layers. This is all gradually broken down and the compost/worm castings can be removed because the worms migrate to the top of the pile, looking for the newly added rotting food waste.
Keep Scotland Beautiful (KSB) has produced a guide for schools on how to build your own wormery, but this can be used by anyone and is available here. The type of worms you should use are not the ordinary garden variety. Instead, Tiger Worms or Dendrobaena could be used, which thrive in rotting organic waste. These worms thrive at lower temperatures (below 30 Celsius) than most composting projects will be aiming for, which means that human/plant pathogens and weeds, will not be killed. This makes it more important to be careful about what is added i.e. do not add meat, or weeds.
You can order worms through the post including from the company Pictish Worms, or Newburgh Worms (Facebook page), both based in the north-east of Scotland. More additional information on setting up and running a wormery is available on the urban worm website.
Click Next Step below – Safe and beneficial use of compost
Click to go back to the Decision-Making Guide Overview
Step 5: Safe and beneficial use of compost
Advice and Training
As interest in community composting grows, some established organisations/projects are offering advice and training. One example in Scotland is Bute Produce which offers affordable Master Composting courses, as described in the Case Studies page. These courses enable residents to gain a greater understanding of the composting process and how to engage with their local communities to raise awareness of composting.
In addition, the highly successful Brighton & Hove Food Partnership run and support many community food growing and composting projects and can provide a quotation for tailored support and advice. Because of the distance to the Highlands this can be provided online.
Understanding What You Can Safely Do With Your Waste and Compost
If you process food waste with animal by-products (e.g. meat, eggs etc) to make your compost you should refer to the Quick Guide to Regulations and Guidance and the Legislation Pdf and follow the link to the APHA’s scoring method. This will assist you in determining if you can store, process and apply this compost to land without being regulated by the Animal and Plant Health Agency (APHA).
Your project is likely to require APHA regulation and oversight if the community compost (made from animal by-products) is to be applied to small holdings or farms. APHA regulation will be required if farmed animals can acces the site where you make the compost. This is also likely to be the case if such animals can access land where the compost is applied. You will be less likely to be regulated if you are aiming to apply such compost to gardens or allotments (this includes community growing projects).
If your compost is made from garden waste and food waste consisting of vegetable and/or fruit waste (e.g. peelings, left-overs, food not suitable for consumption) the APHA does not have any regulatory role.
Risk Assessments
When you are planning your project you should contact your local authority’s environmental health officer to discuss any necessary steps or procedures for the operation of your site, the identification of risks and how to mitigate these.
Avoiding Vermin
If you compost food waste with meat there is the potential for attracting vermin to your site. It is therefore advised that for small scale community projects accepting food waste these should only include vegetable and fruit peelings.
Temperature
Every project will be different and the temperature that you aim to get your compost pile will vary because of this. For example, for wormeries, worms thrive at lower temperatures (below 30°C Celsius) than most composting projects will be aiming for, which means that human/plant pathogens and weeds, will not be killed. This makes it more important to be careful about what is added i.e. do not add meat, or weeds. For most projects composting garden and food waste (veg and fruit peelings) you should try to get your compost pile above 55°C for a number of days under aerobic conditions, this will kill human and plant pathogens. More information on the importance of temperature is available in the guide that can be downloaded:
Financial and Beneficial Use
The page on Looking after local Soils provides information on the nutritional value of composting to soils.
From the perspective of generating financial value it should be noted that producing a good compost does not automatically mean that it is no longer a waste. Compost can be given away or sold to private households, however to be sold openly on the market, PAS100 certification is needed. However, the costs involved in operating to meet this standard are a significant barrier to community projects and in practice this standard will only be achievable by projects working at a scale which is likely to require a waste management licence (i.e. more than 400 tonnes per year). This guide is aimed at community projects, which in all likelihood will be significantly below this level.
You can give your compost away, sell it into the community as long as it is used for gardens, allotments or local community growing projects.
Click Next Step below – How much do community composting projects cost?
Click to go back to the Decision-Making Guide Overview
Step 6: How much do community composting projects cost and how to fund them?
The sources of costs
Community composting projects require the following basic elements:
- Land for locating everything, this might be within a growing project, or on wasteland.
- Containers or vessels for composting as well as equipment such as shredders to prepare garden waste.
- Running costs for any employees, fuel/electricity, insurance etc.
Costs for land will be highly site specific, and may often involve an area being gifted to a community. Considerations and some indications of equipment and running costs are provided below.
The potential for funding your community project is discussed.
Equipment costs
A single, wooden composting bin (see the Case Studies page) could cost circa £300 to make, whilst a whole package of three (for rotating the compost), for a new site could cost circa £1,000 for materials alone. Staff time and any overheads would need to be added on, with a price then being closer to £1,500.
A number of insulated composting bins can be found by searching for these online, and these will cost several hundred pounds each, depending on the size, getting closer to £1,000 for the larger ones.
Rotating vessels (using electricity, applying heat etc) cost several thousands of pounds (tens of thousands for the larger ones).
Heavy duty shredders (two) for reducing garden waste to a compostable size could cost in excess of £1,000.
The document below provides a list of companies (referenced in the Case Studies page) that can be contacted for more accurate and up to date cost information on the equipment above:
Running costs
Experience has shown that projects which rely only on volunteers are at high risk of not being sustainable in the long-term. Therefore projects will be more viable if they employ at least one salaried person even if on a part-time basis. It may be possible to share costs with other community projects by working collaboratively. An example might be a growing project where labour, land and other costs can be pooled together.
Some other cost considerations are:
- Fuel costs for operating shredders will need to be factored into running costs.
- If you choose a composting system which needs electricity then you will have this addtional utility cost. Depending on the location of your site you may also have installation costs to hook up the system.
- Salaries – costs should be based on the real living wage, remembering to also factor in company national insurance and pension.
- Site rental and insurance costs will also need to be considered, which are other good reasons for community composting and local food growing projects to collaborate.
Reducing costs through collaboration
For local growing projects the purchase of compost can be extremely expensive (e.g. food growing, producing planters, etc), costing hundreds, if not thousands of pounds for larger initiatives. Compost produced locally, as an integrated part of a growing project, can therefore avoid these costs, as well as producing a more sustainable, lower carbon, local resource.
Income and funding for community composting projects
Compost can be sold, either at a fixed price, or on a donation basis to householders in your community, raising valuable funds for your project.
There are significant benefits in food growing and composting projects collaborating, which in turn can also create more opportunities for grant funding support, where the objectives could be one or a combination of the following:
- Local food growing
- Diversion of waste from landfill
- Management of resources in a more circular and local way
- Community capacity building – education and skills development
- Reducing carbon emissions associated with the waste and food supply chain
Community composting and food growing projects have often received funding support from a range of sources, including local authorities, the National Lottery etc to deliver against the above objectives. Keep Scotland Beautiful has been successful in securing funding from The National Lottery Community Fund for an exciting community-led programme to address consumption and waste in the Highlands. The Highland Community Waste Partnership will raise awareness of how consumption contributes to climate change, working over three years to create solutions. More information is available here on which communities are being supported and the target outcomes of the programme.
For financial support, an indicative list of potental funding opportunities is shown in the pdf below:
Click Next Step below – summary of the key points for a community composting project?
Click to go back to the Decision-Making Guide Overview
Step 7: Summary of the key points for community composting
Step by step summary
Step 1: What are you going to compost?
- Garden waste is the easiest to compost from a regulations perspective
- Keep it simple – if using food waste, only vegetable and fruit waste (peelings, leftovers etc)
Step 2: How much waste do you want to manage?
- Aim to produce less than 10 tonnes of compost from food waste, if this includes animal by-products
- Consider a project with less than 30 participating households (or multiple projects with less than 30 households)
Step 3: Who could be involved?
- Householders and local food premises (kitchens/canteens)
- Community composting projects will work best when collaborating with local food growing projects, with complementary skills and opportunities to build skills and save money.
Step 4: Technologies and methods
- Keep it simple unless there is a good reason to invest in more costly equipment.
- Build boxes locally to support and encourage the local community to be involved.
Step 5: Safe and beneficial use of compost
- Consult with your local environmental health officer to identify and manage risks
- Sell or give away your compost locally, for use in gardens or community growing projects/allotments. If food waste with animal by-products has been used, do not apply compost to smallholdings, farms or land that can be accessed by farm animals
Step 6: How much do community composting projects cost and how to fund them?
- Costs – keep it simple, with equipment costs for a good quality project able to come in at around £1,000 to £3,000
- Funding (sales) – consider the potential for selling compost to householders locally
- Funding (grants) – collaborate with food growing projects to maximise the potential for grant funding support.
You can download a pdf of this summary page below: