NZQA registered unit standard
27339 version 1
Page 1 of 6
Title
Design on-site waste water treatment and surface water disposal
systems
Level
5
Purpose
Credits
20
This unit standard covers design of drainage systems for onsite disposal. It is intended for use in the training of certifying
drainlayers.
People credited with this standard are able to: obtain site
information; design parameters of system; prepare a plan for a
septic tank system; prepare a plan for a grey water system;
demonstrate knowledge of proprietary on-site treatment
systems; design an on-site effluent disposal system; and
design an on-site surface waste disposal system.
Classification
Plumbing, Gasfitting and Drainlaying > Drainlaying
Available grade
Achieved
Explanatory notes
1
Legislation, standards, codes, and guides applicable to this unit standard include but
are not limited to:
Plumbers, Gasfitters, and Drainlayers Act 2006
Health and Safety in Employment Act 1992
Building Act 2004
Resource Management Act 1991
Local Government Act 2002
Health Act 1956
Plumbers, Gasfitters, and Drainlayers Regulations 2010
AS/NZS 1547:2000 On-site domestic wastewater management (available at
http://www.standards.co.nz)
AS/NZS 1546.1:2008 On-site domestic wastewater treatment units Part 1: Septic
tanks (available at http://www.standards.co.nz)
AS/NZS 1546.3:2001 On-site domestic wastewater treatment units Part 3: Aerated
wastewater treatment systems (available at http://www.standards.co.nz)
AS/NZS 3500.2:200 Plumbing and drainage – Sanitary plumbing and drainage
(available at http://www.standards.co.nz)
Approved Code of Practice for Safety in Excavation and Shafts for Foundations
(Wellington:
Department
of
Labour,
1995)
(available
at
http://www.osh.govt.nz/order/catalogue)
Design guidelines of territorial authorities, which include but are not limited to – Onsite Waste Water Systems: Design and Management Manual (Technical Publication
58), 3rd edition (Auckland Regional Council: August 2004) (available at
http://www.arc.govt.nz)
The Skills Organisation
SSB Code 101554
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
27339 version 1
Page 2 of 6
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 B2 Durability and any related compliance
documents (available at http://www.dbh.govt.nz)
New Zealand Building Code Clause E1 Surface Water and any related compliance
documents (available at http://www.dbh.govt.nz)
New Zealand Building Code Clause G13 Foul Water and any related compliance
documents (available at http://www.dbh.govt.nz).
Any legislation, standard, code, or guide superseding any of the above will apply
pending review of this unit standard.
2
Definitions
Job specifications, for the purposes of this unit standard, refer 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.
Approving authority, for the purposes of this unit standard, includes but is not limited
to territorial authorities, regional councils, network utility operators and building
consent authorities.
Regulatory requirements, for the purposes of this unit standard, refer to applicable
legislation, standards, and codes.
Outcomes and evidence requirements
Outcome 1
Obtain site information.
Range
includes but is not limited to – anticipated demand, site plan, building plan,
reticulation plan, Certificate of Title, contour plan.
Evidence requirements
1.1
Any local conditions and restrictions are determined.
1.2
Site information is relevant.
Range
1.3
includes but is not limited to – ground characteristics, water table,
topography.
Information is sufficient to enable approving authority approval to be obtained.
Outcome 2
Design parameters of system.
The Skills Organisation
SSB Code 101554
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
27339 version 1
Page 3 of 6
Evidence requirements
2.1
Flow rates are calculated.
2.2
A long-section/elevation of the drain is drawn.
Outcome 3
Prepare a plan for a septic tank system.
Evidence requirements
3.1
Nature of tank is determined.
3.2
Invert levels are determined.
3.3
Sanitary fixture locations are determined.
3.4
Plan is drawn and job specifications are prepared.
3.5
Ventilation requirements are shown.
3.6
Inspection points are shown.
3.7
Any ancillary fittings and equipment are shown.
3.8
Resources are used efficiently.
3.9
Completed plan is sufficient to enable regulatory requirements to be met.
3.10
Client information documentation is prepared and contains all relevant
information for client handover.
Range
includes but is not limited to – maintenance schedule.
Outcome 4
Prepare a plan for a grey water system.
Evidence requirements
4.1
Use of a grey water system is appropriate to the situation.
4.2
Invert levels are determined.
4.3
Sanitary fixture locations are determined.
4.4
Plan is drawn and job specifications are prepared.
4.5
Ventilation requirements are shown.
4.6
Inspection points are shown.
The Skills Organisation
SSB Code 101554
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
27339 version 1
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4.7
Resources are used efficiently.
4.8
Completed plan is sufficient to enable regulatory requirements to be met.
4.9
Client information documentation is prepared and contains all relevant
information for client handover.
Range
includes but is not limited to – maintenance schedule.
Outcome 5
Demonstrate knowledge of proprietary on-site treatment systems.
Evidence requirements
5.1
Components and operation of proprietary systems are described.
5.2
Maintenance schedule and monitoring records are described in terms of their
features.
Range
5.3
log books, fault records, pumps, filters, controllers, valves, pipes,
outlets, alarms.
Faults in components and blockages are described in terms of the reasons for
their occurrence and their potential impact on the system.
Outcome 6
Design an on-site effluent disposal system.
Range
system with drip-lines and having pumped delivery, system with trenches or
mounds or sand filters and having siphon, tip bucket or flushing valve delivery.
Evidence requirements
6.1
Site evaluation report is prepared.
Range
includes but is not limited to – tests for soil characteristics
(including the nature of the soil, absorbency, percolation, long term
acceptance rate LTAC), water table, climate, topography.
6.2
Selections of the delivery and disposal systems are appropriate to the situation.
6.3
Plan is drawn and job specifications are prepared.
Range
includes evidence of compliance with New Zealand Building Act
Clause G13 Foulwater.
6.4
Resources are used efficiently.
6.5
Completed plan is sufficient to enable regulatory requirements to be met.
The Skills Organisation
SSB Code 101554
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
6.6
27339 version 1
Page 5 of 6
Client information documentation is prepared and contains all relevant
information for client handover.
includes but is not limited to – maintenance schedule.
Range
Outcome 7
Design an on-site surface waste disposal system.
Range
includes but is not limited to – soak pits.
Evidence requirements
7.1
Site evaluation report is prepared.
includes but is not limited to – tests for soil characteristics
(absorbency, percolation), water table, climate, topography.
Range
7.2
Size of soak pit is calculated.
7.3
Plan is drawn and job specifications are prepared.
Range
includes evidence of compliance with New Zealand Building Code
Clause E1 Surface Water/VM1.
7.4
Resources are used efficiently.
7.5
Completed plan is sufficient to enable regulatory requirements to be met.
Planned review date
31 December 2017
Status information and last date for assessment for superseded versions
Process
Version Date
Last Date for Assessment
Registration
1
15 March 2012
N/A
Consent and Moderation Requirements (CMR) reference
0008
This CMR can be accessed at http://www.nzqa.govt.nz/framework/search/index.do.
Please note
Providers must be granted consent to assess against standards (accredited) by NZQA,
before they can report credits from assessment against unit standards or deliver courses
of study leading to that assessment.
Industry Training Organisations must be granted consent to assess against standards by
NZQA before they can register credits from assessment against unit standards.
The Skills Organisation
SSB Code 101554
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
27339 version 1
Page 6 of 6
Providers and Industry Training Organisations, which have been granted consent and
which are assessing against unit standards must engage with the moderation system that
applies to those standards.
Requirements for consent to assess and an outline of the moderation system that applies
to this standard are outlined in the Consent and Moderation Requirements (CMR). The
CMR 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.
The Skills Organisation
SSB Code 101554
 New Zealand Qualifications Authority 2016