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Describe landfill gas and maintain landfill gas extraction systems

Level / 4
Credits / 25

PurposeThis unit standard is for people who are currently working at a landfill site, in jobs with responsibility for landfill gas extraction.

People credited with this unit standard are able to describe landfill gas, and maintain landfill gas extraction systems.

Subfield / Solid Waste
Domain / Solid Waste Disposal
Status / Registered
Status date / 25 October 2007
Date version published / 25 October 2007
Planned review date / 31 December 2012
Entry information / Open.
Accreditation / Evaluation of documentation and visit by NZQA and industry.
Standard setting body (SSB) / NZ Motor Industry Training Organisation (Incorporated) (MITO)
Accreditation and Moderation Action Plan (AMAP) reference / 0114

This AMAP can be accessed at

Special notes

1All work practices must comply with:

local authority requirements for waste disposal;

landfill management plan.

2Hazard controls, safety procedures, and personal protective equipment must be used throughout operations in accordance with company procedures.

3Definitions

Company procedures means the documented methods for performing work activities and include health and safety, environmental, and quality management requirements. They may refer to manuals, codes of practice, or policy statements.

Site management plan refers to documented guidelines and procedures for operations at the site. It includes consent conditions and legislative requirements

Elements and performance criteria

Element 1

Describe landfill gas.

Performance criteria

1.1Landfill gas production is described in terms of factors influencing its generation.

Rangeanaerobic conditions, composition of refuse quantity and age of waste, condition of the waste mass, moisture content, pH, temperature.

1.2Landfill gas is described in terms of its composition and the characteristics of its components.

Rangecomponents – methane, carbon dioxide, primary gases, volatile organic compounds, hydrogen sulphide.

1.3Landfill gas is described in terms of migration types.

Rangetypes – convection, diffusion, within landfill, to adjacent subsurface soils.

1.4Landfill gas is described in terms of causes and reduction of migration.

Rangecauses – quantity of waste in fill, configuration of landfill, geology of surrounding strata, migratory paths, physical barriers, type of cover, meteorological conditions;

reduction – adsorption into soils, transfer to water, oxidisation by bacteria.

1.5Landfill gas is described in terms of hazards, and possible impacts on people and the environment.

Rangeincludes but is not limited to impacts on – human health, vegetation, climate.

1.6Landfill gas is described in terms of control systems.

Rangepassive system, physical barrier, active systems;

active systems – extraction well, header system, condensate system, treatment system such as flare station, utilisation equipment, perimeter monitoring system.

1.7Landfill gas is described in terms of recovery options.

Rangevertical extraction wells, horizontal collectors, hybrid systems.

1.8Landfill gas is described in terms of treatment options and requirements for their operation.

Rangeopen flare (also known as candlestick), closed flare (also known as ground).

1.9Landfill gas is described in terms of utilisation options.

Rangeoptions – use on site, electricity generation, thermal treatment of leachate, injection into gas pipeline, conversion for vehicle fuel.

Element 2

Maintain landfill gas extraction systems.

Performance criteria

2.1Odour and methane emissions are monitored and controlled in accordance with the site management plan and company procedures.

2.2Active gas discharge control systems are maintained in accordance with the site management plan, local authority requirements, and company procedures.

Rangeat least two of – extraction well, header system, condensate system, treatment system such as flare station, utilisation equipment, perimeter monitoring system.

Please note

Providers must be accredited by NZQA, or an inter-institutional body with delegated authority for quality assurance, before they can report credits from assessment against unit standards or deliver courses of study leading to that assessment.

Industry Training Organisations must be accredited by NZQA before they can register credits from assessment against unit standards.

Accredited providers and Industry Training Organisations assessing against unit standards must engage with the moderation system that applies to those standards.

Accreditation requirements and an outline of the moderation system that applies to this standard are outlined in the Accreditation and Moderation Action Plan (AMAP). The AMAP also includes useful information about special requirements for organisations wishing to develop education and training programmes, such as minimum qualifications for tutors and assessors, and special resource requirements.

Comments on this unit standard

Please contact the NZ Motor Industry Training Organisation (MITO) if you wish to suggest changes to the content of this unit standard.

 New Zealand Qualifications Authority 2018