Canterbury Residential Red Zone Household Hazardous Waste Project

The Canterbury Residential Red Zone Household Hazardous Waste Project was developed to support earthquake recovery by enabling the collection and appropriate disposal of hazardous materials from red zoned residential properties prior to demolition. The key purpose was to minimise the associated risks to human health and the environment.

The devastating effects of the Canterbury Earthquakes of September 2010 and February 2011 continue to shape the city around us as Christchurch recovers. We have seen the overwhelming task of rebuilding a city realised, with a new precinct based central city, changes to transport networks and the re-zoning of land to manage new risks of liquefaction. On a daily basis the changes to the urban landscape remind us of the significance of the events that literally shape the redevelopment of Christchurch.

Decimating the central business district and the majority of historic and tall buildings across the city, the earthquakes also had significant effects in the east and north east residential suburbs. Huge swathes of these suburbs, where liquefaction created a number of issues including the immediate disruption of services and damage to infrastructure, were subsequently assessed and rezoned for demolition, due the property damage which had occurred and instability of land. Affected properties were acquired (compulsorily) by the Crown to ensure the removal of the hazard posed by residential development on instable ground, creating the Canterbury Residential Red Zone (RRZ).

The dispersion of people as a result of the earthquake and the restricted access meant that many of these properties were left in an as is state, still containing an undisturbed cache of personal possessions and household items, including hazardous substances and materials which would need appropriate disposal. Many of the common household items that would typically be managed through council collection services where likely to be present in these properties. The unknown volume and types of hazardous material posed a significant risk to human health and the environment if not managed properly; with drainage to storm water and contamination of soil likely. It also posed an occupational risk to demolition companies, while management had the potential to cause delays and otherwise hinder the recovery process.

In 2011, the Canterbury Earthquake Recovery Authority (CERA), Environment Canterbury, Christchurch City Council (CCC) and Waimakariri District Council (WDC) formed a working group to address the significant volume of household hazardous waste (HHW) orphaned through the compulsory demolition of approximately 8,000 residential properties. The result was a coordinated cross agency approach for safely managing the collection and disposal of this hazardous material, enabling safe demolition of the red zoned properties and supporting earthquake recovery.

Environment Canterbury took a leadership role and in January 2012 successfully attained funding from the Ministry for the Environment for a three year project to remove and safely dispose of an estimated 100 tonnes of HHW with 20 percent of properties expected to contain HHW.

The collaborative project utilised existing council collection systems and advertising to promote the clearance of properties by residents where possible. In addition to this licensed removals contractors visited each individual property, checking for, identifying and removing any hazardous material remaining, otherwise referred to as Household Hazardous Waste (HHW).

Council drop-offs: Existing collection mechanisms (Council Transfer Stations) were provided funding to open up their collection sites for RRZ properties, so that individuals could dispose of HHW appropriately when leaving their RRZ properties. This was supported with advertising and a communications campaign which built on existing information on HHW. This was very successful with over 200 tonnes of HHW collected through these sites. Christchurch City Council and Waimakriri District Council provided the in-kind staff time and grant funding covered the disposal of HHW generated in addition to calculated background collection quantities for each site.

Using these existing sites which were known to the local communities was particularly successful, building on the existing knowledge around disposal of hazardous substances, with the infrastructure already in place to manage this waste stream in an appropriate manner. WDC and CCC also provided assisted collections for those unable to drop off their HHW material, this applied to elderly and infirm residents.

Communications were key to this with an information brochure (based on existing collection information) developed and disseminated to all properties defined within the RRZ. Regular advertisements were also posted in Local newspapers.

Property clearances: Contracts were awarded to two Waste Management companies to conduct the inspection and removal of HHW from all RRZ properties prior to demolition. CERA appointed a project manager to coordinate the clearances, with ECan, CCC and WDC forming a steering group to manage issues as they arose.

Initially CERA planned to coordinate the removal of HHW prior to demolition through a cluster based approach, grouping areas of red zoned properties for demolition and working closely with demolition contractors to coordinate the clearances. After an initial trial in the suburb of Bexley, key difficulties accessing damaged and unsafe properties were highlighted as were physical risks: Damaged land; electrical hazards and overgrown vegetation were common as were a number of illegal occupations of damaged buildings. Together the parties involved worked through these hazards and established a notification and access protocol. This approach should have allowed the systematic and safe clearance of all properties prior to demolition.

Unfortunately this systematic approach was not realised due to complications in the settlement process, with many residents choosing to settle for the property value with CERA and improvement (house) value separately with their insurer/The Earthquake Commission (EQC). This led to sporadic clearances as properties were settled, communication between CERA, the insurance companies and demolition contractors were poor, making the process near impossible to manage efficiently, because of this some demolitions occurred without notification, with buildings removed before clearance of HHW. This was exactly what the project sought to prevent.

An adaptive response was required; the reliance on the insurance companies was an entirely reactive process, with the insurance companies often not providing the necessary notification to allow the project manager to arrange clearance of HHW. This approach also caused inefficiencies and access difficulties for the removal contractors. A flexible approach was required.

Formulation of the Waste and Emergency Management Team (WEMT), a cross agency team including former compliance and health and safety officers from CCC and ECan was a pivotal change in the model. WEMT took over the Project Management role and utilised a proactive approach, working closely with Project Management Officers (representing Insurance companies), demolition contractors and the waste removal contractors to coordinate the clearances of properties before demolition was scheduled. Establishment of this field team improved communication, providing a flexible approach and building relationships between the involved parties.

Along with coordinating property clearances, WEMT also provided regular auditing to ensure the removals contractors were reporting accurately. Through which we have a robust dataset of the material collected from the 6,768 properties inspected for hazardous substances prior to demolition across the duration of the project. This data is particularly interesting as it represents a statistically significant snapshot of the HHW present in our homes. By understanding the types and volumes of material stored, local authorities and interested organisations will be able to better prepare for future disaster scenarios and target their day to day programs to reduce the risk of these products effecting the environment.

The project was completed in December 2015, four years after it began. With the majority of RRZ properties now demolished. Clearances encompassed both Christchurch flatland and Port Hills properties deemed uninhabitable. While access, site safety and coordination of clearances did pose some issues, the project achieved an effective clearance of 84 percent of properties in the RRZ, a significant triumph given the complexities of the project.

The project was an incredible success with over 334 tonnes of household hazardous waste collected and disposed of appropriately. This material included over 200 additional tonnes of HHW dropped off at council transfer stations, a real testament to the in kind time provided by WDC and CCC and over 130 tonnes collected directly from properties in the RRZ.

The total expenditure over the course of the Project was $1.16million. This was provided through the funding from the Ministry for the Environment’s Waste Minimisation Fund ($863,000) and in-kind contributions from WDC, CCC and ECan. Key successes for the project included but were not limited to the safe collection, treatment and disposal of the above wastes, protecting human health and the environment. Through the separate collection of these materials the project also supported an enhanced demolition-waste management process, avoiding contamination of demolition materials and diverting these materials from landfills and managed fills. This project forms one element of a much larger recovery process but was pivotal in the timely and effective management of the demolition waste stream; in effect the project supported earthquake recovery.

The project also provided a positive example of how a cross-agency response can achieve a positive outcome in a disaster response situation and provides a template for how to deal with household hazardous waste during earthquake disaster recovery.

Key project players include and deserve acknowledgement; Chris Keeling (former Hazardous Substances and Waste officer, Environment Canterbury) in getting this hugely complex and difficult project up and running. Liam Tarpey (Senior Compliance Officer, Waste and Emergency Management Team (WEMT) in accessing RRZ properties to locate and identify hazardous substances prior to removal and providing collection audits. Kitty Waghorn (Solid Waste Manager, Waimakariri District Council) and Sue Winter (Christchurch City Council) were both heavily involved coordinating the Transfer station drop-offs at their respective sites. Both also played a key role in the projects governance.