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Publications
Griffith University and the Department of the Environment, Sport & Territories, 1997
ISBN 0 868 57655 7
This workshop introduces participants to the concepts and techniques of environmental auditing and related activities as tools to assist government and industry in achieving improved environmental performance.
The use of the information derived from these investigatory activities in producing Management Systems or Plans and State of Environment Reports is discussed.
During this workshop participants will:
A brief explanation introduces reviews and audits as essential steps in achieving improved environmental performance through planning and state of environment reporting.
A stimulus activity based on a simple review of the local environment. A mini-lecture introduces the role of auditing as a management tool.
A group activity to develop school policies and action plans to achieve environmental performance goals.
Participants work as auditors to assess data on the environmental performance of a school in a hypothetical education district and produce a State of Environment Report.
General discussion comparing recommendations from the previous activity.
A group activity on the appropriateness of developing a State of Environment Report for their own school as a classroom activity.
Overhead transparency masters
OHT 1: Environmental Review Scale
OHT 2: Environmental Considerations of School/Home
OHT 3: Objectives, Actions and Goals
Resources
Resource 1: Environmental Auditing (EA)
Resource 2: Management Plan
Resource 3: Environmental Review of Gumnut High School
Resource 4: Site Layout of Gumnut High School
Resource 5: Environmental Audit Data
Resource 6A: Air Quality
Resource 6B: Soil Quality
Resource 6C: Water Quality
Activity 3: One blank OHT for each group of participants
Activity 4: One blank OHT for each group of participants
Australian Chamber of Manufacturers and State Chambers of Commerce and Industry (1992) Environment Management Handbook for Small Business.
Brown, G.A. (1993) Environmental Audit Guidebook, Centre for Professional Development, Law Book Group, Victoria.
Brown, G.A. (1994) Environmental Awareness and Obligation, Centre for Professional Development, Law Book Group, Victoria.
Cheremisinoff, P. and Cheremisinoff, N. (1993) Professional Environmental Auditors' Guidebook, Noyes Publications, New Jersey, USA.
Grayson, L. (1992) Environmental Auditing: A Guide to Best Practice in the UK and Europe, The British Library Science Reference and Information Service and Technical Communications, Letchworth, UK.
ICC Guide to Effective Environmental Auditing (1991), ICC Publishing S.A., Paris, France.
Hall, R.M. and Case, D.R. (1992) All About Environmental Auditing, Federal Publications Inc., Washington DC.
Schools Environmental Audit - A Guide to Best Practice Environmental Management, Keep Australia Beautiful (New South Wales and South Australian editions available).
Standards Association of Australia (1995) Interim Environmental Management Standards (Draft International Standards - DIS 14000) on Environmental Management Systems - Guideline for Use and Specifications etc.
Woolston, H. (1993) Environmental Auditing: An Introduction and Practical Guide, The British Library Science Reference and Information Service and Technical Communications, Letchworth, UK.
Briefly introduce the idea that minimising environmental degradation and rehabilitating the existing environment requires knowledge of the current local environmental status, auditing skills, planning and improved environmental planning. To manage activities which can impact on the environment, we need data about the environment and what needs to be changed. Environmental reviews and audits are vital tools in environmental management.
Display OHT 1. Ask participants to work in pairs to consider their local environment's state of well being or health, using the criteria on the OHT or their own viewpoints.
Determine the 'average' consensus of the group and mark it on the OHT.
Show OHT 2 on environmental considerations of the school/home. Ask which are relevant.
Suggest to participants that accurate evaluation of the environment requires data, not just a visual check. Collection of this data is an audit. Deliver a mini-lecture on environmental auditing using Resource 1.
An environmental management plan consists of an aim, objectives and actions. Working in small groups, ask participants to develop environmental objectives for a school (e.g. the school will reduce water consumption and waste; the school will commence recycling).
The groups report back and then work together to develop a set of school environmental objectives. Allocate each group some of the objectives to identify possible actions to achieve these objective (e.g. purchase of colour-coded bins to assist recycling; planting of native gardens to support native birds; commencement of a school awareness program to introduce the students to water conservation).
Ask participants to develop practical goals to measure the success of the actions in achieving improved environmental performance. Show OHT 3 as an example. Summarise these on an OHT and report back to the other groups.
Stress the importance of providing time frames to implement their plans and the need for an audit program to check and measure improved environmental performance. Provide Resource 2 for discussion and comparison with group results.
Participants work as auditors to assess data and report on the environmental performance of a school in a hypothetical education district. A State of Environment Report is developed.
The report should be prepared following these steps:
Present the following scenario to participants:
An environmental review was initiated by the school involving an examination of each component of the site to identify gaps in knowledge, determine suitable management practices and collect data such as site layout and results from monitoring.
It is your role as auditors to prepare a State of Environment Report for the school using the provided data and documentation.
Break participants into small groups of even numbers (if possible) and distribute Resource 3, Resource 4, Resource 5, and Resources6A , B and C. Allow a short time for review.
Ask groups to divide the schools into manageable domains, suggesting that the numbers of people in the group would be a suitable number of divisions. Mark these domains on a map.
Ask groups to identify what they think would be good environmental indicators to use in describing the state of environment for each domain.
Ask groups to compare Resource 5 with Resources 6A, B and C to assess the State of Environment for each domain. It should be clear that to either improve or maintain the present state of environment objectives for each area must be developed. Allow the groups at least 15 minutes to develop objectives for each domain.
Ask groups, based on their objectives, to identify options to achieve these. (Rehabilitation measures, regulation, policies or reduction procedures could be suggested.)
Groups now prepare their final State of Environment Report in point form on an OHT and present their reports outlining the major measures.
Groups compare the final recommendations. Use the following questions in the general discussion:
Ask participants to consider how difficult it would be to undertake an audit in their school.
Working in pairs, ask participants to outline the procedures needed to implement an audit and develop a State of Environment Report with management practices for their own school and local environment.
Criteria:
You could consider the following:
The term environmental auditing is often confused with the terms: review; (contaminated) site assessment; environmental impact assessment (EIA); and monitoring. Similarly, 'waste audits' are most commonly not audits but involve the practical characterisation and analysis of waste streams.
Site assessments usually apply to contaminated areas. The assessment is based on sampling of the site and chemical and/or microbiological analysis of the samples. Where contaminant levels are higher than prescribed for the proposed land use, site remediation will be required to bring those contaminant levels down to the levels set by the regulatory authority. Homebush Bay in Sydney is a significant contaminated site which is currently being assessed and remediated as the proposed site of the Olympic village.
Monitoring involves a regular, preprogrammed collection of data either by electronic means 'on line' or through a program of sampling and laboratory analysis. If the data are to form part of a future audit program, then the analytical results will usually be undertaken by an accredited external laboratory for subsequent verification purposes.
An AUDIT involves collection and evaluation of verifiable information - usually written.
The most widely used definition of environmental auditing comes from the 1989 ICC Position Paper on Environmental Auditing which defines it as:
A management tool comprising a systematic, documented, periodic and objective evaluation of how well environmental organisation, management, and equipment are performing with the aim of helping to safeguard the environment by:
Most EAs currently undertaken are for compliance purposes only (i.e. emissions and effluent discharge levels are compared with the provisions stated in a site licence for the organisation). In contrast, an ENVIRONMENTAL REVIEW is usually undertaken to assess the initial/current environmental status of an organisation or site. In many such instances, there is little documented information and the review serves to identify gaps in data and essential record keeping. The techniques/skills required for conducting reviews and audits are similar.
The review can be used to develop an Environmental Management Plan (or System) which will provide policy statements and action plans aimed at improving the environmental performance of the organisation. As part of such a plan, monitoring and record keeping systems are introduced to provide information for future audits. These audits then assist the organisation to check and evaluate its environmental performance against predetermined goals (audit criteria). The techniques used in a review are similar to those of an audit but initially there is usually very little documentation to support the assessment.
The information obtained and evaluated in both reviews and audits can be used to produce a State of Environment Report for the organisation. Government is looking to combining and paraphrasing such organisational and local government SOEs from many sources across the broad community to produce regional and national SOEs. Such a report would contain specific information on direct local environmental degradation and failures to meet all regulatory requirements. In addition, positive environmental aspects are evaluated for inclusion in the report. The Department of the Environment, Sport and Territories is producing a document to standardise SOE reporting across Australia. This will consider how environmentally relevant information collected across the state or nation can be compiled into an SOE for the community. In addition, Australia produced a national State of the Environment Report in 1996.
Environmental auditing is an important management tool for both government and industry in ensuring that environmental performance goals and objectives are achieved. However, auditing in itself is of little value unless it occurs within a management framework which enables a set of criteria to be developed against which performance can be assessed. Such a framework is provided by an Environmental Management System (EMS).
These elements are used to address the environmental management issues of leadership, training, procedures, planning, incidents, auditing and engineering.
Once a sound EMS has been established by an organisation, then environmental auditing can be used as a useful management tool in assessing, controlling and correcting a wide range of activities associated with the overall system. Some of the areas/issues include:
Governments also use EAs formally to investigate a company which they consider may not be meeting its licence conditions. In such cases, the auditor is afforded regulatory powers under specific Acts and the results of the audit may be used in court proceedings.
Aim: To provide a clean, safe environment for working and learning for both staff and students.
Objectives:
Buildings and Grounds
Sports Oval
Car Park
Native Revegetation and Garden Areas
Monitoring Programs
Management Actions:
Gumnut Tree district has a population of approximately 40,000 people, the district supports one high school of 1,000 pupils.
The topography of the site is a 1 in 10 slope from south to north (i.e. towards the creek). The northern boundary is a small creek which drains into a major river that supports a small fishing industry in the district. A sensitive bushland habitat borders the western boundary of the site which supports a wide variety of local wildlife and is used for research purposes by local conservation groups. The eastern boundary is bordering a rapidly developing residential estate and the southern boundary is bordering a main road used by many local business as well as the school buses.
1. Buildings and Grounds
Buildings on the site consist of:
Science Department - Four chemistry laboratories which are used by both junior and senior students for practical experiments. All waste chemicals used in laboratories are collected in bottles and taken away for correct disposal; minor chemicals which are used for small experiments and cleaning of equipment are disposed of in sinks.
Arts Department - Two art studios and one classroom. All practical work is conducted in studios, any leftover paint or solvents are collected and take away for proper disposal; brushes, etc. are cleaned in sink areas. All waste paper is placed in bins for recycling or burning in the schools small incinerator.
Woodwork/Industrial Metal Workshops - One woodwork and one industrial metal workshop. All scrap wood is stockpiled behind the workshops; scrap metal is disposed of in bins provided, as are floor sweepings.
Home Science Department - One classroom and two kitchens. All food wastes including organics and inorganics are disposed of in small bins located in kitchens.
Canteen/Kitchen - Some food sold is prepackaged; lunches are prepared in kitchen. Waste from lunches is disposed of in kitchen bins.
Library/Computer Rooms - A central library and two computer rooms. All waste paper is disposed of in bins.
General Classrooms - (i.e. Maths, History, Staffroom, etc.). All wastes generated from this area of buildings is disposed of in bins located in individual classrooms.
2. Sports Oval The sports oval consists of two football ovals, a main running oval and concrete tennis, netball and basketball courts. The football and running ovals are fertilised with urea (i.e. nitrogen) and irrigated on a regular basis using mains water.
3. Car Park The car park has a capacity of 100 cars and is fully sealed. The car park is connected to the stormwater drainage which leads to the creek. There are no devices (i.e. gully traps) used to collect oil, grease or grit from cars. The school also monitors soil, water quality of creek, air pollution, noise levels, and keeps records of waste volumes generated from departments. The location of sampling sites can been seen from site layout.
|
Parameter |
Level (Units as indicated) |
|
|
|
Sample 1 |
Sample 2 |
|
pH |
6.7 |
6.7 |
|
Org C (g/kg) |
151.0 |
140.0 |
|
Soluble solids |
25.0 |
26.0 |
|
Total N (g/kg) |
18.9 |
25.0 |
|
Total P (g/kg) |
10.3 |
9.7 |
|
Metals (mg/kg) |
|
|
|
Total arsenic (As) |
3.3 |
2.9 |
|
Total cadmium (Cd) |
148.3 |
190.0 |
|
Total copper (Cu) |
256.0 |
300.0 |
|
Total zinc (Pb) |
1500.0 |
900.0 |
|
Total lead (Pb) |
375.0 |
325.0 |
|
Analysis |
S1 |
S2 |
S3 |
S4 |
S5 |
|
pH |
6.1 |
6.3 |
6.2 |
5.9 |
5.6 |
|
Org C (%) |
17.9 |
9.5 |
19.4 |
6.5 |
7.8 |
|
Sand (%) |
89.0 |
83.0 |
84.0 |
82.0 |
86.0 |
|
Clay (%) |
10.0 |
12.0 |
11.0 |
14.0 |
17.0 |
|
CEC (cmol/kg) |
9.1 |
8.5 |
8.8 |
10.4 |
12.6 |
|
EC (uS/cm) |
57.0 |
69.0 |
49.0 |
198.0 |
285.0 |
|
Metals |
|
|
|
|
|
|
Total Pb |
608.0 |
56.0 |
906.0 |
89.0 |
360.0 |
|
Total Zn |
.05 |
1.1 |
0.9 |
9.6 |
21.5 |
|
Pesticides (mg/kg) |
|
|
|
|
|
|
Lindane |
50.3 |
40.5 |
60.3 |
54.1 |
45.5 |
|
Aldrin |
0.14 |
0.24 |
0.27 |
0.35 |
0.35 |
|
Dieldrin |
0.11 |
0.14 |
0.17 |
0.15 |
0.30 |
|
DDT |
0.11 |
0.14 |
0.17 |
0.15 |
0.30 |
|
Analysis |
W1 |
W2 |
W3 |
|
pH |
7.6 |
7.3 |
7.2 |
|
Org C (%) |
1.5 |
2.1 |
2.3 |
|
EC (uS/cm) |
793.0 |
953.0 |
846.0 |
|
Metals (mg/kg) |
|
|
|
|
Total lead Pb |
2.3 |
1.6 |
1.9 |
|
Total zinc Zn |
1.1 |
0.3 |
0.7 |
|
Pesticides (mg/kg) |
|
|
|
|
Aldrin |
0.01 |
0.03 |
0.05 |
|
Dieldrin |
0.01 |
0.03 |
0.05 |
|
DDT |
0.01 |
0.05 |
0.03 |
|
Lindane |
1.3 |
0.9 |
2.3 |
|
Pollutant |
Level (ug/m3) |
|
Carbon Monoxide CO |
12 000.0 |
|
Nitrogen Dioxide No2, NO2 |
290.0 |
|
Lead Pb |
1.0 |
|
Department |
Weight (kg) or Volume (litres) per week |
|
Science Paper Chemicals |
20 kg 7 litres |
|
Arts Departement Paints/Solvents Paper |
12 litres 50 kg |
|
Woodwork/Industrial Metal Workshops Organics Inorganics |
30 kg 20 kg |
|
Canteen/Kitchen |
175 kg |
|
Library/Computer Rooms Paper |
75 kg |
|
General Classroom Paper |
10 kg |
Source: NHMRC and Australian Environment Council (1985) National Guidelines for Control of Air Pollutants from New Stationary Sources. The NHMRC health guidelines for carbon monoxide (CO), nitrogen dioxide (NO2), and lead are as follows:
|
Pollutant |
Goals |
Measurement Criteria |
|
|
|
ug/m3 |
ppm |
|
|
CO |
10 000 |
9.0 |
8 hour average not to be exceeded more that once per year |
|
NO2 |
320 |
0.16 |
1 hour level not to be exceeded mote than once per month |
|
Lead |
1.5 |
- |
90 day average not to be exceeded |
The lead emissions are based on average lead content for fuel of 0.4 g/l, whereas the 1985 average for Brisbane is 0.74 g/l. As an upper limit, we can assume nitrogen dioxide is half the value for NOx, although the range can be of the order of 0.05-0.8. Near a roadway it may range from 0.05 up to 0.5, although this upper limit will be an overestimate as more than 90% of the direct emissions of NOx will be initially in the form of NO and it then depends how quickly the reaction to NO2 proceeds.
It is clear that the LINE programme will yield hourly levels of CO concentrations and the previous equations will yield the corresponding hourly level for NO2 and the corresponding daily level for lead (once the adjustment for the assumed lead in petrol is carried out). However, the standards require an 8 hour average for CO and a 90 day average for lead. Empirical evidence based on the analysis of statistical data sets
Source: ANZECC (1992) Guidelines for the Assessment and Management of Contaminated Sites.
Australian Soil Investigation Criteria
Australian Soil Investigation Guidelines, or Environmental Soil Quality Guidelines, have been developed by ANZECC, and are based on the Dutch criteria. The ANZECC Guidelines for the Assessment and Management of Contaminated Sites provide background levels (Level A), and interim investigation threshold levels (Level B). In general, when the concentration of individual contaminants falls in or below the range given for Level A, the site can be regarded as uncontaminated. If the concentration exceeds Level B, additional site investigation is required.
|
Contaminant |
Level A (background) |
Level B (environmental investigation) |
|
Heavy Metals |
|
|
|
Antimony (Sb) |
4.44 |
20b |
|
Arsenic (As) |
0.3 - 30a |
20b |
|
Barium (Ba) |
20 - 200 |
|
|
Cadmium (Cd) |
0.04 - 2 |
3c |
|
Chromium (Cr) |
0.5 - 110 |
50b |
|
Cobalt (Co) |
2 - 170 |
|
|
Copper (Cu) |
1 - 190** |
60b |
|
Lead (Pb) |
<2 - 200 |
300 |
|
Manganese (Mn) |
4 - 12600 |
500b |
|
Mercury (Hg) |
0.001 - 0.1 |
1d |
|
Molybdenum (Mo) |
<1-20 |
|
|
Nickel (Ni) |
2 - 400 |
60b |
|
Tin (Sn) |
1 - 25 |
50 |
|
Zinc (Zn) |
2 - 180 |
200 |
|
Mineral Pollutants |
|
|
|
Boron (B) |
1 - 75 |
|
|
Phenolic Compounds |
|
|
|
Phenols |
0.03 - 0.5 |
|
|
Monocyclic Aromatic Hydrocarbons (MAH) |
|
|
|
Benzene |
0.05 - 1 |
1d |
|
Toluene |
0.1 - 1 |
|
|
Chlorinated Hydrocarbons (PCB) |
|
|
|
PCB (total) |
0.02 - 0.1 |
|
|
Pesticides |
|
|
|
Aldrin |
<0.001 - <0.05 |
1 |
|
Dieldrin |
<0.005 - <0.05 |
0.2 |
|
DDT |
<0.001 - 0.97 |
|
|
Other Chemicals |
|
|
| Sulphate |
35 - 1000 |
2000d |
|
pH |
6 - 8 |
|
** excludes known orchard soils
a Victorian Department of Agriculture and Rural Affairs (1990);
b, c, d Environment Canada (1988)
Source: Chapman, D. (1992) Water Quality Assessment: A Guide to the Use of Biota, Sediment and Water in Environmental Monitoring, World Health Organisation.
|
Organism |
Unit |
Guideline Value |
Remarks |
|
1. Microbiological Quality |
|
|
|
|
A. Piped Water Supplies |
|
|
|
|
A.1 Treated water entering the distribution system |
|
|
|
|
Faecal coliforms |
number/100ml |
0 |
Turbidity <1 NTU; for disinfection with chlorine, pH preferably |
|
Coliform organisms |
number/100ml |
0 |
<8.0; free chlorine residual 0.2-0.5 mg/L following 300 min (minimum) contact |
|
A.2 Untreated water entering the distribution system |
|
|
|
|
Faecal coliforms |
number/100ml |
0 |
|
|
Coliform organisms |
number/100ml |
0 |
In 98% of samples examined throughout the year - in the case of large supplies when sufficient samples are examined |
|
Coliform organisms |
number/100ml |
3 |
In an occasional sample, but not in consecutive samples |
|
A.3 Water in the distribution system |
|
|
|
|
Faecal coliforms |
number/100ml |
0 |
|
|
Coliform organisms |
number/100ml |
0 |
In 95% of samples examined throughout the year - in the case of large supplies when sufficient samples are examined |
|
Coliform organisms |
number/100ml |
3 |
In an occasional sample, but not in consecutive samples |
|
B. Unpiped Water Supplies |
|
|
|
|
Faecal coliforms |
number/100ml |
0 |
|
|
Coliform organisms |
number/100ml |
10 |
Should not occur repeatedly; if occurrence is frequent and if sanitary protection cannot be improved, an alternative source must be found if possible |
|
C. Bottled Drinking Water |
|
|
|
|
Faecal Coliforms |
number/100ml |
0 |
Source should be from faecal contamination |
|
Coliform organisms |
number/100ml |
0 |
|
|
D. Emergency Water Supplies |
|
|
|
|
Faecal coliforms |
number/100ml |
0 |
Advise public to boil water in case of failure to meet guideline value |
|
Coliform organisms |
number/100ml |
0 |
|
|
Enteroviruses |
no guideline value set |
0 |
|
|
2. Biological Quality |
|
|
|
|
Protozoa (pathogenic) |
no guideline value set |
|
|
|
Helminths (pathogenic) |
no guideline value set |
|
|
|
Free-living organisms (algae, others) |
no guideline value set |
|
|
|
Constituent |
Guideline Value* |
|
Arsenic |
0.05 |
|
Asbestos |
No guideline value set |
|
Barium |
No guideline value set |
|
Beryllium |
No guideline value set |
|
Cadmium |
0.005 |
|
Chromium |
0.05 |
|
Cyanide |
0.1 |
|
Fluoride** |
1.5 |
|
Hardness |
No health-related guideline value set |
|
Lead |
0.05 |
|
Mercury |
0.001 |
|
Nickel |
No guideline value set |
|
Nitrate |
10 |
|
Nitrite |
No guideline value set |
|
Selenium |
0.01 |
|
Silver |
No guideline value set |
|
Sodium |
No guideline value set |
* All values are in mg/L
** Includes both natural fluoride and deliberately add fluoride. Local conditions may necessitate adaptation.
|
Constituent |
Guideline Value* |
Remarks |
|
Aldrin and dieldrin |
0.03 |
|
|
Benzene |
10† |
|
|
Benzo (a) pyrene |
0.01† |
|
|
Carbon tetrachloride |
3† |
Tentative guideline value‡ |
|
Chlordane |
0.3 |
|
|
Chlorobenzenes |
No health related guideline value set |
Odour threshold concentration 0.1pg/L |
|
2,4-D |
100§ |
|
|
DDT |
1 |
|
|
1,2-Dichloromethane |
10† |
|
|
1,1-Dichloroethene¶ |
0.3† |
|
|
Heptachlor and Heptachlor epoxide |
0.1 |
|
|
Hexachlorobenzene |
0.01† |
|
|
Gamma-HCH (lindane) |
3 |
|
|
Methoxychlor |
30 |
|
|
Pentachlorophenol |
10 |
|
|
Tetrachloroethane¶ |
10† |
Tentative guideline value ‡ |
|
Trichloroethane¶ |
30† |
Tentative guideline value‡ |
|
2,4,6-Trichlorophenol |
10†¶ |
Odour threshold concentration 0.1pg/L |
|
Trihalomethanes |
No guideline value set |
|
* All values are in pg/L
†These guideline values were computed from a conservative hypothetical mathematical model which cannot be experimentally verified, and values should therefore be interpreted differently. Uncertainties involved may amount to two orders of magnitude (i.e. from 0.1 to 10 times the number).
‡When the available carcinogenicity data did not support a guideline value, but the compounds were judged to be of importance in drinking water and guidance was considered essential, a tentative guideline value was set on the basis of the available health-related data.
§ May be detectable by taste and odour at lower concentrations.
¶ These compounds were previously known as 1,1-dichloroethylene, tetrachlorothylene, and trichloroetylene, respectively.
|
Constituent |
Guideline Value* |
Remarks |
|
Aluminium |
0.2 |
|
|
Chloride |
250 |
|
|
Chlorobenzenes and chlorophenols |
No guideline value set |
These compounds may affect tast and odour |
|
Colour |
15 TCU† |
|
|
Copper |
1.0 |
|
|
Detergents |
No guideline value set |
There should not be any foaming, taste or odour problem |
|
Hardness |
500 (as CaCO3) |
|
|
Hydrogen sulphide |
Not detectable by consumers |
|
|
Iron |
|
0.3 |
|
Manganese |
0.1 |
|
|
Oxygen, dissolved |
No guideline value set |
|
|
pH |
|
6.5 - 8.5 |
|
Sodium |
200 |
|
|
Solids, total dissolved |
1000 |
|
|
Sulfate |
400 |
|
|
Taste and odour |
Inoffensive to most consumers |
|
|
Temperature |
No guideline value set |
|
|
Turbidity |
5 NTU‡ |
Preferably <1 for disinfection efficiency |
|
Zinc |
|
5.0 |
* Unless otherwise specified, all units are mg/L
†TCU - true colour unit
‡NTU - nephelometric turbidity unit
|
Constituent |
Guideline Value* |
Remarks |
|
Gross alpha activity |
0.1 |
If the levels are exceeded, more detailed radiouclide analysis may be necessary. |
|
Gross beta activity |
1 |
Higher levels do not necessarily imply that the water is unsuitable for human consumption |
* Units are Bq/L
