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Describe domestic wastewater land application systems, and their
selection, for site and soil characteristics
Level
5
Credits
8
Purpose
This unit standard is intended for people who are responsible for the design,
installation, monitoring, and regulation of on-site domestic wastewater
systems.
People credited with this unit standard are able to demonstrate knowledge of
domestic wastewater land application systems and the factors affecting
selection of land application systems.
Subfield
Water Industry
Domain
Wastewater Treatment
Status
Registered
Status date
17 October 2008
Date version published
17 October 2008
Planned review date
31 December 2011
Entry information
Open.
Accreditation
Evaluation of documentation and visit by NZQA, industry
and teaching professional in the same field from another
provider.
Standard setting body (SSB)
Primary Industry Training Organisation
Accreditation and Moderation Action Plan (AMAP) reference
0179
This AMAP can be accessed at http://www.nzqa.govt.nz/framework/search/index.do.
Special notes
1
Legislation relevant to this unit standard includes but is not limited to the Resource
Management Act 1991, Building Act 2004 and relevant Building Codes, Health Act
1956.
2
Rules and requirements for wastewater include but are not limited to those found in
regional and district plans, and regulatory authority requirements.
 New Zealand Qualifications Authority 2016
25125 version 1
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3
The standard applicable to this unit standard is AS/NZS 1547:2000 On-site domestic
wastewater management, available from http://www.standards.co.nz.
4
References
Design guidelines of territorial authorities, which include but are not limited to On-site Wastewater Systems: Design and Management Manual (Technical
Publication 58), 3rd edition (Auckland Regional Council: August 2004, available at
http://www.arc.govt.nz.
Guidelines for on-site sewage systems in the Wellington Region (WRC/RP-G-00/47),
(Greater Wellington Regional Council: February 2001), available at
http://www.gw.govt.nz.
On-site wastewater guidelines for the Manawatu-Wanganui Region (20/EXT/381),
(Horizons Manawatu: November 2000), available at http://www.horizons.govt.nz.
Guidelines for new on-site wastewater management systems (Marlborough District
Council: July 2005), available at http://marlborough.govt.nz.
It is recommended that the assessor uses design guidelines issued by the regional or
local authorities in the candidate’s locality.
5
Credit for this unit standard does not qualify the candidate to work in a drainlaying
situation that comes under the drainlayer’s licence requirements issued under the
Plumbers, Gasfitters, and Drainlayers Act 2006 and any subsequent amendments.
Elements and performance criteria
Element 1
Demonstrate knowledge of domestic wastewater land application systems.
Range
conventional trenches, shallow and narrow trench systems, discharge control
trench systems, deep trench systems, infiltration systems, soak pits,
conventional beds, evapotranspiration beds, mound land application systems,
bottomless sand filters, low-pressure effluent distribution (LPED), irrigation, drip
irrigation, primary effluent irrigation, drip irrigation of secondary effluent
(subsurface and surface covered drip).
Performance criteria
1.1
Land application systems are described in terms of their function, effluent
distribution method, design requirements, operation, and maintenance of the
distribution system.
Range
1.2
design loading rates (DLR), applied effluent quality, land area
requirements, evapotranspiration assist, reserve areas, dosing
and resting requirements, commissioning requirements.
Land application systems are described in terms of their configuration and
construction, construction media requirements, planting, surface and
subsurface water-flow paths controls and system, operation, and maintenance
requirements.
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Element 2
Demonstrate knowledge of the factors affecting selection of land application systems.
Performance criteria
2.1
Selection of the land application system is described in relation to soil category.
Range
2.2
Selection of the land application system is described in relation to site and soil
constraints.
Range
2.3
includes but is not limited to – neighbouring systems, separation
distance, cumulative effects of nutrients, pathogens and indicator
micro-organisms, rainfall intensity, risks from pathogens, nutrient
balance, depth of ground water and direction of flow, local uses of
groundwater and surface waters, type of aquifer and sensitivity to
contamination, groundwater mounding.
Selection of the land application system is described in relation to client
requirements and cost factors.
Range
2.5
includes but is not limited to – soil profile, restrictive horizon, slope,
contour, aspect, vegetation, clearances to site features.
Selection of the land application system is described in relation to
environmental constraints.
Range
2.4
soil texture and structure, indicative permeability, indicative
drainage characteristics.
design reporting, technology choice, construction options,
operation and maintenance implications, monitoring and
inspection responsibilities, property facilities.
Selection of the land application system is described in accordance with
regional and district council requirements.
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.
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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 Primary Industry Training Organisation standards@primaryito.ac.nz if
you wish to suggest changes to the content of this unit standard.
 New Zealand Qualifications Authority 2016