Resolution
MEPC.159(55)
REVISED GUIDELINES ON IMPLEMENTATION OF
EFFLUENT STANDARDS AND PERFORMANCE TESTS FOR SEWAGE TREATMENT PLANTS
(Adopted on 13 October 2006)
Revoked by MEPC.227(64) adopted on 5 October 2012
THE
MARINE ENVIRONMENT PROTECTION COMMITTEE,
RECALLING
Article 38(a) of the Convention on the International Maritime Organization
concerning the functions of the Marine Environment Protection Committee (the
Committee) conferred upon it by international conventions for the prevention
and control of marine pollution,
NOTING
resolution MEPC.2(VI) adopted on 3 December 1976 by which the Marine
Environment Protection Committee adopted, at its sixth session, the
Recommendation on International Effluent Standards and Guidelines for
Performance Tests for Sewage Treatment Plants and invited Governments to apply
the Effluent Standards and Guidelines for approving sewage treatment plants; to
take steps to establish testing programmes in accordance with the Guidelines
for Performance Tests; and provide the Organization with a list of sewage
treatment plants meeting the standards,
NOTING
ALSO resolution MEPC.115(51) adopted on 1 April 2004 by which the Marine
Environment Protection Committee adopted, at its fifty-first session, the
revised MARPOL Annex IV and which entered into force on 1 August 2005,
NOTING
FURTHER the provisions of regulation 9.1.1 of MARPOL Annex IV, in which
reference is made to the above-mentioned guidelines,
RECOGNIZING
that resolution MEPC.2(VI) should be amended in order that current trends for
the protection of the marine environment and developments in the design and
effectiveness of commercially available sewage treatment plants be reflected;
and the proliferation of differing unilateral more stringent standards that
might be imposed worldwide be avoided,
HAVING
CONSIDERED the recommendation made by the Sub-Committee on Bulk Liquids and
Gases, at its tenth session,
1.
ADOPTS the Revised Guidelines on Implementation of Effluent Standards and
Performance Tests for Sewage Treatment Plants, the text of which is set out in
the Annex to this resolution;
2.
INVITES Governments to:
(a) implement
the Revised Guidelines on Implementation of Effluent Standards and Performance
Tests for Sewage Treatment Plants and apply them so that all equipment
installed on board on or after 1 January 2010 meets the Revised Guidelines in
so far as is reasonable and practicable; and
(b) provide the
Organization with information on experiences gained from their application and,
in particular, on successful testing of equipment against the Standards;
3.
FURTHER INVITES Governments to issue an appropriate "Certificate of type
approval for Sewage Treatment Plants" as referred to in paragraph 5.4.2
and the annex of the Revised Guidelines and to recognize such certificates
issued under the authority of other Governments as having the same validity as
certificates issued by them; and
4.
SUPERSEDES the Recommendation on International Effluent Standards and
Guidelines for Performance Tests for Sewage Treatment Plants contained in
resolution MEPC.2(VI).
Annex.
REVISED GUIDELINES ON IMPLEMENTATION OF EFFLUENT STANDARDS AND PERFORMANCE
TESTS FOR SEWAGE TREATMENT PLANTS
1.
Introduction
2.
Definitions
3.
General
4.
Standards
5.
Testing considerations
6.
Renewal and additional surveys
7.
Familiarization of ship personnel in the use of the sewage treatment plant
Annex.
FORM OF CERTIFICATE OF TYPE APPROVAL FOR SEWAGE TREATMENT PLANTS AND APPENDIX
REVISED
GUIDELINES ON IMPLEMENTATION OF EFFLUENT STANDARDS AND PERFORMANCE TESTS FOR
SEWAGE TREATMENT PLANTS
1.1
The Marine Environment Protection Committee (MEPC) of the International
Maritime Organization (IMO) adopted resolution MEPC.2(VI) Recommendation on
International Effluent Standards and Guidelines for Performance Tests for
Sewage Treatment Plants in 1976.
1.2
This document contains the Revised Guidelines on Implementation of Effluent
Standards and Performance Tests for Sewage Treatment Plants (Guidelines). These
Guidelines are intended to assist Administrations in establishing operational
performance testing programmes for sewage treatment plants for the purpose of
type approval under regulation 9.1.1 of Annex IV of the Convention.
1.3
These Guidelines apply to sewage treatment plants installed on board on or
after 1 January 2010.
Annex
IV - the revised Annex IV of the International Convention for the Prevention of
Pollution from Ships (MARPOL 73/78) as amended by resolution MEPC.115(51).
Convention
- the International Convention for the Prevention of Pollution from Ships
1973/1978 (MARPOL 73/78).
Geometric
mean - the nth root of the product of n numbers.
Greywater
- is drainage from dishwater, shower, laundry, bath and washbasin drains.
Testing
onboard - testing carried out on a sewage treatment plant that has been
installed upon a ship.
Testing
ashore - testing carried out on a sewage treatment plant prior to installation
e.g. in the factory.
Thermotolerant
coliforms - the group of coliform bacteria which
produce gas from lactose in 48 hours at 44.5ºC. These organisms are
sometimes referred to as "faecal coliforms"; however, the term
"thermotolerant coliforms" is now accepted as more appropriate, since
not all of these organisms are of faecal origin.
3.1
An approved sewage treatment plant must meet the standards in section 4 and the
tests outlined in these Guidelines. It should also be noted that, when ships
are operating approved sewage treatment plants, Annex IV also provides that the
effluent shall not produce visible floating solids or cause discolouration of
the surrounding water.
3.2
It is acknowledged that the performance of sewage treatment plants may vary
considerably when the system is tested ashore under simulated shipboard
conditions or onboard a ship under actual operating conditions. Where testing
ashore demonstrates that a system complies with the standards, but subsequent
onboard testing does not meet the standards, the Administration should determine
the reason and take it into account when deciding whether to type approve the
plant.
3.3
It is recognized that Administrations may wish to modify the specific details
outlined in these Guidelines to take account of very large, very small or
unique sewage treatment plants.
4.1
For the purpose of regulation 4.1 of Annex IV, a sewage treatment plant should
satisfy the following effluent standards when tested for its Certificate of
Type Approval by the Administration:
.1
Thermotolerant Coliform Standard
The geometric
mean of the thermotolerant coliform count of the samples of effluent taken
during the test period should not exceed 100 thermotolerant coliforms/100 ml as
determined by membrane filter, multiple tube fermentation or an equivalent
analytical procedure.
.2 Total
Suspended Solids (TSS) Standard
(c) The
geometric mean of the total suspended solids content of the samples of effluent
taken during the test period shall not exceed 35 mg/l.
(d) Where the
sewage treatment plant is tested onboard ship, the maximum total suspended
solids content of the samples of effluent taken during the test period may be
adjusted to take account of the total suspended solid content of the flushing
water. In allowing this adjustment in maximum TSS, Administrations shall ensure
sufficient tests of TSS are taken of the flushing water throughout the testing
period to establish an accurate geometric mean to be used as the adjustment
figure (defined as x). In no cases shall the maximum allowed TSS be greater than
35 plus x mg/l.
Method of
testing should be by:
.1 filtration of
representative sample through a 0.45 µ m filter membrane, drying at 105°C and
weighing; or
.2 centrifuging
of a representative sample (for at least five minutes with mean acceleration of
2,800-3,200 g), drying at least 105°C and weighing; or
.3 other
internationally accepted equivalent test standard.
.3 Biochemical
Oxygen Demand and Chemical Oxygen Demand
Administrations
should satisfy themselves that the sewage treatment plant is designed to reduce
both soluble and insoluble organic substances to meet the requirement that, the
geometric mean of 5-day Biochemical Oxygen Demand (BOD5) of the
samples of effluent taken during the test period does not exceed 25 mg/l and
the Chemical Oxygen Demand (COD) does not exceed 125 mg/l. The test method
standard should be ISO 15705:2002 for COD and ISO 5815-1:2003 for BOD5,
or other internationally accepted equivalent test standards.
.4 pH
The pH of the
samples of effluent taken during the test period shall be between 6 and 8.5.
.5 Zero or
non-detected values
For thermolerant
coliforms, zero values should be replaced with a value of 1 thermotolerant
coliform/100 ml to allow the calculation of the geometric mean. For total
suspended solids, biochemical oxygen demand and chemical oxygen demand, values
below the limit of detection should be replaced with one half the limit of
detection to allow the calculation of the geometric mean.
4.2
Where the sewage treatment plant has been tested ashore, the initial survey
should include installation and commissioning of the sewage treatment plant.
5.1
Testing of the operational performance of a sewage treatment plant should be
conducted in accordance with the following subparagraphs. Unless otherwise
noted, the subparagraphs apply to testing both onboard and ashore.
5.2.1
Sewage treatment plants tested ashore - the influent should be fresh sewage
consisting of faecal matter, urine, toilet paper and flush water to which, for
testing purposes primary sewage sludge has been added as necessary to attain a
minimum total suspended solids concentration appropriate for the number of
persons and hydraulic loading for which the sewage treatment plant will be
certified. The testing should take into account the type of system (for example
vacuum or gravity toilets) and any water or greywater that may be added for
flushing to the sewage before treatment. In any case the influent concentration
of total suspended solids should be no less than 500 mg/l.
5.2.2
Sewage treatment plants tested onboard - the influent may consist of the sewage
generated under normal operational conditions. In any case the average influent
concentration of total suspended solids should be no less than 500 mg/l.
5.3 Duration and timing of test
5.3.1
The duration of the test period should be a minimum of 10 days and should be
timed to capture normal operational conditions, taking into account the type of
system and the number of persons and hydraulic loading for which the sewage
treatment plant will be type approved. The test should commence after
steady-state conditions have been reached by the sewage treatment plant under
test.
5.4.1
During the test period the sewage treatment plant should be tested under
conditions of minimum, average and maximum volumetric loadings.
.1 For testing
ashore, these loadings will be as laid down in the manufacturer’s
specifications. Figure 1 shows suggested timings for sampling each loading
factor.
.2 For testing
onboard, minimum loading will represent that generated by the number of persons
on the ship when it is alongside in port, and average and maximum loadings will
represent those generated by the number of persons on the ship at sea and will take
account of meal times and watch rotations.
5.4.2
The Administration should undertake to assess the capability of the sewage
treatment plant to produce an effluent in accordance with the standards
prescribed by section 4 following minimum, average and maximum volumetric
loadings. The range of conditions under which the effluent standards were met
should be recorded on the Certificate of Type Approval. The form of the
Certificate of Type Approval and appendix is set out in the annex to these
Guidelines.
5.5 Sampling methods and
frequency
5.5.1
Administrations should ensure that the sewage treatment plant is installed in a
manner which facilitates the collection of samples. Sampling should be carried
out in a manner and at a frequency which is representative of the effluent
quality. Figure 1 provides a suggested frequency for sampling, however, the
frequency should take account of the residence time of the influent in the
sewage treatment plant. A minimum of 40 effluent samples should be collected to
allow a statistical analysis of the testing data (e.g. geometric mean, maximum,
minimum, variance).
5.5.2
An influent sample should be taken and analysed for every effluent sample taken
and the results recorded to ensure compliance with section 4. If possible,
additional influent and effluent samples should be taken to allow for a margin
of error. Samples should be appropriately preserved prior to analysis
particularly if there is to be a significant delay between collection and
analysis or during times of high ambient temperature.
5.5.3
Any disinfectant residual in samples should be neutralized when the sample is
collected to prevent unrealistic bacteria kill or chemical oxidation of organic
matter by the disinfectant brought about by artificially extended contact
times. Chlorine (if used) concentration and pH should be measured prior to
neutralization.
5.6 Analytical testing of
effluent
5.6.1
The Administration should give consideration to the recording of other
parameters in addition to those required (thermotolerant coliforms, total
suspended solids, BOD5, COD, pH and residual chlorine) with a view
to future technological development. Parameters which might be considered
include total solids, volatile solids, settlable solids, volatile suspended
solids, turbidity, total phosphorus, total organic carbon, total coliforms and
faecal streptococci.
5.7.1
The potential adverse environmental effects of many disinfectant residuals and
by-products, such as those associated with the use of chlorine or its
compounds, are well recognized. It is, therefore, recommended that
Administrations encourage the use of ozone, ultra-violet irradiation or any
other disinfectants which minimize adverse environmental effects, whilst
pursuing the thermotolerant coliform standard. When chlorine is used as a
disinfectant, the Administration should be satisfied that the best technical
practice is used to keep the disinfectant residual in the effluent below 0.5
mg/l.
5.8.1
Only full-scale marine sewage treatment plants should be accepted for testing
purposes. The Administration may certify a range of the manufacturer’s
equipment sizes employing the same principles and technology, but due
consideration must be given to limitations on performance which might arise
from scaling up or scaling down. In the case of very large, very small or
unique sewage treatment plants, certification may be based on results of
prototype tests. Where possible, confirmatory tests should be performed on the
final installation of such sewage treatment plants.
5.9 Environmental testing of the
sewage treatment plant
5.9.1
The Administration should be satisfied that the sewage treatment plant can
operate under conditions of tilt consistent with internationally acceptable
shipboard practice.
5.9.2
Tests for certification should be carried out over the range of temperature and
salinity specified by the manufacturer, and the Administration should be
satisfied that such specifications are adequate for the conditions under which
the equipment must operate.
5.9.3
Control and sensor components should be subjected to environmental testing to
verify their suitability for marine use. The Test Specifications section in
part 3 of the annex to resolution MEPC.107(49) provides guidance in this
respect.
5.9.4
Any limitation on the conditions of operation should be recorded on the
Certificate.
5.9.5
The Administration should also consider requiring the manufacturer to include
in the operating and maintenance manuals, a list of chemicals and materials
suitable for use in the operation of the sewage treatment plant.
5.10.1
The type and model of the sewage treatment plant and the name of the
manufacturer should be noted by means of a durable label firmly affixed
directly to the sewage treatment plant. This label should include the date of
manufacture and any operational or installation limits considered necessary by
the manufacturer or the Administration.
5.10.2
Administrations should examine the manufacturer’s installation, operating and
maintenance manuals for adequacy and completeness. The ship should have on
board at all times a manual detailing the operational and maintenance
procedures for the sewage treatment plant.
5.10.3
Qualifications of testing facilities should be carefully examined by the
Administration as a prerequisite to their participation in the testing
programme. Every attempt should be made to assure uniformity among the various
facilities.
6. RENEWAL AND
ADDITIONAL SURVEYS
6.1
Administrations should endeavour to ensure, when conducting renewal or
additional surveys in accordance with regulations 4.1.2 and 4.1.3 of Annex IV,
that the sewage treatment plant continues to perform in accordance with the
conditions outlined in regulation 4.1.1 of Annex IV.
7.
FAMILIARIZATION OF SHIP PERSONNEL IN THE USE OF THE SEWAGE TREATMENT PLANT
7.1
Recognizing that the appropriate regulations relating to familiarization are
contained within the Ships Safety Management Systems under the International
Safety Management Code, Administrations are reminded that ship staff training
should include familiarization in the operation and maintenance of the sewage
treatment plant.
Annex.
FORM OF CERTIFICATE OF TYPE APPROVAL FOR SEWAGE TREATMENT PLANTS AND APPENDIX