Biosolids Master Plan

Biosolids are a nutrient-rich, solid by-product of wastewater treatment. At Winnipeg's sewage treatment plants, the solids are separated from the liquid wastewater. These solids, also known as sludge, consist mainly of organic matter, are further treated and dewatered. After treatment, the solids are called biosolids.

• We are required to submit a Biosolids Master Plan to the province by October 2014, with the following considerations:
  • sustainable reuse of biosolids and/or end product(s)
  • utilization of nutrients (nitrogen and phosphorous)
  • possible energy recovery

The Biosolids Master Plan must outline a strategy to manage biosolids to 2037.

We typically review master plans when:

• a major system component requires upgrading,
• there is a significant change to regulatory requirements (e.g., Environment Act licences for the sewage treatment plants).

Yes. In Canada, production, transport, use (including beneficial use) and disposal of biosolids are regulated on a provincial/territorial basis.

About 13,500 dry tonnes of biosolids were produced in 2012.

• Non-biosolids related material (e.g., grit, miscellaneous solid waste material) is landfilled at the Brady Road Resource Management Facility.
• Quantities vary greatly on a seasonal basis (e.g., increased grit enters the system in the winter from sanding of roads and runoff in the spring).
• Non-biosolids material generated in 2012:
  • 2375 tonnes at the north end plant
  • 622 tonnes at the south end plant
  • 210 tonnes at the west end plant

• Biosolids management is an issue world-wide, particularly with more stringent regulations, environmental concerns and social change.
• A variety of management options for biosolids are in use in Canada, including:
  • composting
  • land revitalization/restoration (landfill cover, large construction sites, surface strip mines, parks and road cuts, wetlands, wildlife habitat and conservation areas)
  • land application
  • thermal oxidation
  • pelletization
  • landfill (not considered sustainable reuse)

• Up until January 1, 2011, we would deliver, spread and incorporate a portion of our biosolids into agricultural land at no cost to landowners. The amount would vary depending on a number of factors (e.g., weather). For example, in 2010, we applied 48% of the biosolids on the land.
• Since then, we have been landfilling biosolids at Brady Resource Management Facility (Brady Landfill).

As a result of concerns about nutrient overloading in Lake Winnipeg, a Provincial regulation was enacted that prohibited the spreading of biosolids on land in winter, and decreased the loading rate of biosolids to farmland.

• Yes. We are moving forward with a $7 million two-year pilot program to compost biosolids at the Brady Resource Management Facility, which will be able to compost 20% of our biosolids.
• Composting biosolids produces a stable end product high in organic matter which can be used as a soil amendment.
• Depending on the results of the pilot, the composting option could be a long term solution for dealing with all or part of Winnipeg's biosolids.

• We will be looking for the most cost effective option or combination of options.
• This is the first time we have explored external interest, so it is too early to know.
• This Request for Information will help us understand the market implications.

Yes, this is a consideration in assessing possible solutions.

• The treatment processes at the North End Sewage Treatment Plant currently have some older technology (e.g., clarifiers used in biosolids treatment) as well as some recent upgrades with state-of-the-art technology (e.g., ultraviolet light disinfection to reduce pathogens).
• Some of the older technology is still considered effective/best practice (e.g., clarifiers and anaerobic digesters in the biosolids treatment process).

• In July 2010, City Council enacted a new Sewer By-Law that included a new Pollution Prevention Planning Program for industries that is intended to reduce or possibly eliminate pollutants of potential concern.
• This program shifts the focus of wastewater treatment from control to prevention at source, and requires business and industry to continually evaluate materials, processes and practices involved in their operations.
• Industries not in compliance with the by-law limits must, within a specified time period, provide detailed plans to get into compliance or be subject to fines.

• Many compounds of concern are difficult to control in that they are excreted naturally into the sewer system (e.g., medications not fully metabolized, hormones).
• There are limits in the Sewer By-Law for many contaminants and industries out of compliance are subject to the Pollution Prevention Program.
• Research on the impact of emerging compounds of concern on the environment is ongoing, and the City and the Province are following the research developments with the intent of controlling their discharge where sources and control methods can be identified.

• No. Composting toilets aren't an option for our urban setting primarily for the protection of public health, and therefore do not comply with the National Plumbing Code and are prohibited under the City of Winnipeg Sewer By-Law.
• Composting toilets are more suited to small rural communities (e.g., Whiteshell) where the population is very small, and environmental considerations and isolation preclude the use of other systems.

• Yes. The main portions of the composting process that have the potential to create odours are covered with wood chips. This would include the area where the biosolids are mixed with bulking agents.
• The pilot program will evaluate the effectiveness of all the odour control measures, including a biofilter.

• The biosolids composting facility will operate independently of the leaf and yard waste composting operation, at least initially, to allow for a proper evaluation of each operation.
• There will be overlap in those areas that can optimize operating costs, but won't impact the evaluation (e.g., equipment, staff).

No. The void spaces would not be adequate for proper air circulation.

Yes. We will purchase recycled tree waste woodchips for the pilot.

No. The anaerobic composting process is more complex to manage and operate because it requires:

• additional resources to handle the methane gas that it produces, and
• a reliable source of food waste (e.g., a kitchen organics curbside collection program).

We would first have to evaluate the potential for nuisance odour.

• No. The licence for the two-year pilot program does not allow for the composted material to leave the site. We will use the compost on-site as landfill cover and as a soil revitalization material.
• Before we can distribute to a market off-site, we must first be able to demonstrate that the finished compost material is pathogen free and qualifies a "Class A" product.

Additional components can be added to increase the composting capacity if that is a decision of the Master Plan.

We will be evaluating:

• the impact on surrounding neighbourhoods (e.g., nuisance odour), and
• operational requirements (e.g., availability of suitable bulking agents).

There is more than 100 years of landfill capacity, including the option of landfilling 100% of biosolids.

This land application program was discontinued in 2010 due to more stringent provincial nutrient regulations under the Water Protection Act as a result of concerns about nutrient overloading in Lake Winnipeg.

• Yes. The province has defined soil types where spreading of biosolids is permitted as well as the quantity of biosolids permitted to be spread.
• The soil types are based on a site specific analysis of nitrogen and phosphorous for defined depths of soil for each nutrient.

• 3.3%N : 2.3%P
• 1.4N : 1P

• The provincial Nutrient Management Regulations do not currently permit more intense spreading rates.
• The allowable spreading rates are based on soil analyses, particularly for background phosphorous concentrations prior to spreading.

The Province of Manitoba Nutrient Management Regulation governs the application of biosolids to land
www.gov.mb.ca/waterstewardship/wqmz

The Province of Manitoba outlines crop restrictions in the environmental licences for land application programs. The following crops can be grown for a period of three years after the application of biosolids: cereal crops, forage crops, oil seed crops, field peas, soybeans, lentils and corn. After the three year period, farm producers are not restricted to what they can grow. Biosolids land application is not permitted on direct edible crops (i.e., potatoes, carrots, onions).

Land application of biosolids has minimal risk to the environment, provided all regulations are followed. The biosolids land application program will comply with all provincial regulations, including the provincial Nutrient Management Regulation.

The purpose of the Nutrient Management Regulation is to protect water quality by encouraging responsible nutrient application. The Regulation has defined zones that determine where biosolids can be applied. Biosolids cannot be applied in the nutrient buffer zone, which includes land near water bodies, wetlands, groundwater features, flood zones, etc.

The nutrients are concentrated in the ash that remains after firing the biosolids.

• Depending on the concentration of contaminants in the ash, it can be land applied to utilize the phosphorous in the ash.
• We are not aware of technologies to extract the phosphorous from the ash.

Yes. Ash can be applied to land as long as the concentration of metals complies with the provincial Nutrient Management Regulation.

The treatment process of pelletization (heat and drying) kills the pathogens, resulting in a Class A product.

• Yes. The Canadian Food Inspection Agency and the Canadian Council of Ministers of the Environment both have standards for heavy metals content of marketable fertilizer product.
• A granulated product from Winnipeg's biosolids is expected to meet these standards and could be registered as a fertilizer. However, the final product would also be required to meet certain physical characteristics to be deemed as marketable.

• This Request for Information (RFI) is a key part of the process in developing a long term plan for managing Winnipeg's biosolids.
• It will help us understand private sector interest and the financial implications for biosolids reuse.

• We will evaluate and consider all proposals.

• We used the following activities to communicate the RFI:
  • issued news releases (August 2, September 3),
  • advertised in local papers,
  • posted information on the City's website on a dedicated biosolids web page,
  • contacted relevant vendors, and
  • hosted an information session.