21946 version 1
Page 1 of 4
Demonstrate knowledge of the installation of on-site wastewater
treatment systems
Level
4
Credits
6
Purpose
This unit standard is for people who work, or intend to work, in the drainlaying
industry.
People credited with this unit standard are able to: demonstrate knowledge of
on-site wastewater treatment system requirements; demonstrate knowledge
of excavation and preparation of sub-base for on-site wastewater treatment
systems; describe the installation of on-site wastewater treatment systems;
and describe backfilling and site clearance; and demonstrate knowledge of
regulatory requirements, selection of methods and materials, and
underpinning concepts and principles, as applied to the installation of on-site
wastewater treatment systems.
Subfield
Plumbing, Gasfitting and Drainlaying
Domain
Drainlaying
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)
The Skills Organisation
Accreditation and Moderation Action Plan (AMAP) reference
0008
This AMAP can be accessed at http://www.nzqa.govt.nz/framework/search/index.do.
Special notes
1
Legislation, codes, and guides relevant to this unit standard includes but is not limited
to:
Health and Safety in Employment Act 1992;
Building Act 2004;
Resource Management Act 1991;
 New Zealand Qualifications Authority 2016
21946 version 1
Page 2 of 4
Approved Code of Practice for Excavation and Shafts for Foundations (Wellington:
Department of Labour, 1995);
Guide for Safety with Underground Services (Wellington: Department of Labour,
2002); available at http://www.osh.govt.nz/order/catalogue;
New Zealand Building Code, Clause E1 Surface Water, current version and any
related compliance documents, available at http://www.dbh.govt.nz.
May include:
Health Act 1956.
Any legislation, standard, code, or guide superseding any of the above will apply,
pending review of this unit standard.
2
Range
on-site wastewater treatment systems may include – pre-cast concrete, in-situ,
evapotranspiration beds, soakage trenches, soakage pits, Low Pressure Effluent
Dosing (LPED) systems.
3
Definitions
Job specifications, for the purpose of this unit standard, refers to instructions (oral,
written, graphic) and may include any of the following: manufacturers’ instructions;
design drawing detail specifications; specifications from a specialist source such as
an architect, designer, engineer, or a supervisor; and site or work specific
requirements. Where job specifications are in conflict with applicable legislation,
standards, and/or codes, such legislation, standards, and/or codes shall take
precedence for the purpose of assessment.
On-site wastewater treatment system is defined as a secondary effluent treatment
system designed to deal with anaerobic, aerobic, and filtration effluent by sand
filtration, trickling bio-filter systems, and extended aeration systems.
Other services refers to any existing installed services such as water, gas, electricity,
or telephone network cables.
Regulatory requirements, for the purpose of this unit standard, refers to applicable
legislation, standards, and codes.
Elements and performance criteria
Element 1
Demonstrate knowledge of on-site wastewater treatment system requirements.
Performance criteria
1.1
Site requirements are identified in terms of the plant, ground conditions,
topography, and territorial authority’s requirements.
1.2
Type of plant required is identified in terms of ground conditions, occupation,
and loading.
1.3
Work records and plans are described in accordance with the relevant territorial
authority’s requirements.
 New Zealand Qualifications Authority 2016
21946 version 1
Page 3 of 4
Element 2
Demonstrate knowledge of excavation and preparation of sub-base for on-site wastewater
treatment systems.
Performance criteria
2.1
Location, avoidance, and protection of other services are described in
accordance with the owning utility operator’s working practice.
2.2
Identification of other services by label and/or colour is described in accordance
with job specifications and relevant standards and codes.
2.3
Excavation is described in accordance with job specifications.
2.4
Identification of stable sub-base is described in accordance with visual
assessment and job specifications.
2.5
Selection, placement, and levelling of base material are described in
accordance with job specifications.
Element 3
Describe the installation of on-site wastewater treatment systems.
Performance criteria
3.1
Positioning of on-site wastewater treatment systems is described in accordance
with job specifications.
3.2
Installation of on-site wastewater treatment systems is described in accordance
with job specifications.
3.3
Maintenance of water supply protection is described in accordance with job
specifications.
Element 4
Describe backfilling and site clearance.
Performance criteria
4.1
Site backfilling, and compaction as necessary, are described in accordance with
job specifications.
4.2
Site clearance of construction debris and working equipment is described in
accordance with job specifications.
 New Zealand Qualifications Authority 2016
21946 version 1
Page 4 of 4
Element 5
Demonstrate knowledge of regulatory requirements, selection of methods and materials
used, and underpinning concepts and principles, as applied to the installation of on-site
wastewater treatment systems.
Performance criteria
5.1
Relevant sections of legislation, standards, and codes are described in terms of
their application to the installation of on-site wastewater treatment systems.
5.2
Selection of methods and materials is justified.
Range
5.3
job specifications, operation of the installed system and
components; may include job requirements.
Underpinning concepts and principles are explained in terms of their application
to the installation of on-site wastewater treatment systems.
Range
aerobic and anaerobic treatment, hydrostatics and hydraulics,
siphon.
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 Skills Organisation info@skills.org.nz if you wish to suggest changes
to the content of this unit standard.
 New Zealand Qualifications Authority 2016