Why does compost matter?

In Nova Scotia organics (i.e. food and yard waste) are banned from disposal in landfills. The Halifax region was the first large municipality in Canada to implement a source separate organics program in 1998, including curbside collection of green carts. Over 53,000 tonnes of organics are processed annually at one of two centralized compost facilities and other third party entities.

Why are we talking about it now?

Our current organics facilities are over 17 years old and with the success of our programs have reached their processing capacity. As well, new compost maturity guidelines were adopted by Nova Scotia Environment (NSE) in 2010, with compliance anticipated by 2019/20 - no firm date has been given by NSE. Our existing facilities cannot meet these guidelines without expansion or replacement.There have been many advances and insights made in the field of compost. The Halifax region now has an opportunity to look at a range of options with a long term outlook of managing our organic waste. No decisions have been made as to what type of system we will engage.

On October 27, 2016 Nova Scotia Environment confirmed “no deadline has been set for complying with the guidelines, and there are no proposals being brought forward at this time to establish one".

How can I get involved?

We are seeking your input on what matters most when considering compost systems and operations. This feedback will help form the basis of a Request for Qualifications where industry will submit proposals to help grow Halifax’s organics management system. The goal is to have new strategy/solution operational in 2019/2020.

Attributes have been grouped under four pillars: Our Environment, The Social Context, Finances & Risk and Logistics. Please the survey here at www.shapeyourcity.ca/compost-matters or send us an email to compostmatters@halifax.ca

What is composting?

Composting is the process by which organic material breaks down into a product that can be used to add nutrients and moisture to soil. Many residents manage organic waste on their properties through backyard composting, mulch mowing and grasscycling.

Are there different systems for composting?

Yes.

Aerobic (with air) composting is used in our current facilities. Simply put, nitrogen-rich food waste and carbon-rich yard waste are mixed along with oxygen and moisture (if needed). These controlled conditions encourage micro-organisms to break down the organic material. Heat is generated during this process, which kills bacteria and pathogens. The end product is compost.
  • Our current facilities process material inside a building. Material remains in the building for up to 28 days, after which it is transported off site for further processing.

  • Open windrow operations are an outdoor process where material is piled in rows and turned by machines. The material stays in these rows for up to 12 months before it is ready to be used.
Anaerobic digestion is the breakdown of organic material (i.e. food waste, yard waste) in an oxygen-free environment. Anaerobic processes can typically handle wetter organic material. The active microorganisms in this process create a combustible gas (methane and carbon dioxide), known as biogas.
  • Biogas can be an energy source when captured and converted to electricity or a form of natural gas. Anaerobic digesters optimize conditions and help reduce odours. The end product (digestate) can be composted and used as a fertilizer. Anaerobic digestion facilities generally accept materials not traditionally captured in an aerobic process (i.e. plastic and compostable bags and pet waste).

On-farm anaerobic digestion facilities typically use manure as the main feedstock. Other organic materials (such as food waste) can be added to increase the biogas production. On-farm anaerobic operations do exist in Nova Scotia, but there is no proven experience with green bin waste material.

Why isn't compost currently available to residents?

The compost end product is managed by a third party who owns the material. This means the product is not currently available to be returned to residents as is the practice in many other municipalities.

Where will compost facilities be located?

Finding ways to manage organics that maximize resource value and minimize impact on our neighbours is essential. Organics processing facilities generate odours and noise as a result of operating equipment and managing green bin material. This has the potential to negatively affect the local community if not well managed.

The municipality currently operates two compost plants (in Burnside and in Goodwood, Halifax) located within a 10 km radius of the centre of where the majority of organics are generated.

Existing facilities may be used with the new processing solution, the current sites may be used for new infrastructure, or other approved sites may be used. New sites are subject to approval by Nova Scotia Environment and must comply with municipal land use By-Laws.

How large a facility will we need?

Facility size will vary depending upon the technology selected. Aerobic composting typically requires a larger facility footprint than a fully mechanical process such as anaerobic digestion. Accommodating a new plant or process on an existing compost facility site or the need to develop a new location will largely depend on the technology selected.

What is the cost of processing organics?

Processing  organics costs the municipality approximately $9 million per year ($170/tonne).  A new system is estimated to cost between $150 - $210 per tonne, depending on the technology and process chosen.


What about new technology?

New composting technologies exist but some are unproven. Using unproven technology  increases the financial and operational risk. The Halifax Regional Municipality has been a pioneer and leader in organic waste management. Our future may include selecting commercially proven technology for processing source-separated organics, or less tested and perhaps more innovative solutions that can also meet our needs

What if regulations change again?

It is important that any proposed technology is robust enough to potentially meet future requirements. This can be accomplished through developing a system which exceeds current standards, or ensuring the proposed solution can be convienently upgraded. Stricter compost quality requirements recently introducted in Ontario could forseeably be applied to Nova Scotia over the operating life of the new facility. 

How large a facility will be required?

The current capacity of each facility is 25,000 tonnes, but the municipality generates over 53,000 tonnes annually. This means during high-volume periods (spring, fall and Christmas tree removal), material must be re-directed to alternative sites. Future planning will allow for potential tonnage of 60,000 to 75,000 tonnes.

Is a new facility necessary?

Not necessarily.  One consideration is determining whether expansion can occur at existing sites. This could occur through expanding the current process technology or perhaps adding new technology to co-exist on one of the existing sites and work in tandem with current facilities. Alternatively, an existing facility could be demolished to facilitate a new operation. Other options include a new site and facility or keeping an existing facility operational through renovation.

How long would it take to have a new site operational?

New site identification, permitting and zone approval and community consultation may be required to ensure the proposed development is consistent with land use in the area. This affects project deadlines, operations and cost. It is likely that this process will take a few years depending on the planning and approval process through various levels of government.