CELEX: 51979PC0296
Language: en
Date: 1979-06-14
Title: Proposal for a COUNCIL DIRECTIVE on the limit values applicable to discharges of mercury into the aquatic environment by the chlor-alkali electrolysis industry#Proposal for a COUNCIL DIRECTIVE on the quality objectives for the aquatic environment into which mercury is discharged by the chlor-alkali electrolysis industry (submitted to the Council by the Commission)

ARCHIVES HISTORIQUES
DE LA COMMISSION
COLLECTION RELIEE DES
DOCUMENTS "COM"
COM (79) 296
Vol. 1979/0114
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 ---pagebreak--- COMMISSION OF THE EUROPEAN COMMUNITIES
                                                 COM(79)296 final
                                                 Brussels / June 1979
                                  Proposal for a
                                 COUNCIL DIRECTIVE
          on the limit values applicable to discharges of mercury
          into the aquatic environment by the chlor-alkali electro­
                                  lysis industry
                                  Proposal for a
                                COUNCIL DIRECTIVE
         on the quality objectives for the aquatic environment
         into which mercury is discharged by the chlor-alkali
                              electrolysis industry
                                      A
              ,• ( submitted to the Council by the Commission )
              V  v
                               : 1     ■ .
C0MC79 ) 296 final
 ---pagebreak---                      EXPLANATORY MEMORANDUM
Introduction
In their concern to combat the pollution of fresh and sea water "by
the discharge of dangerous substances , the European Economic
Community and its Member States have become Contracting Parties to
international conventions whose purpose is to reduce and eventually
eliminate this type of pollution ( the Convention for the Prevention
of Marine Pollution from Land–based Sources and the Convention on
the Protection of the Rhine against Chemical Pollution ), and are
taking part in negotiations for other conventions with the same
 purpose .   To ensure the harmonized implementation of these conven­
 tions and to launch a general and simultaneous effort by the Member
 States , the Council on 4 May * 976 approved Directive 7 0/464/sSG on
 pollution caused by certain dangerous substances discharged into the
  aquatic environment of the Community .   This Directive stipulates ,
  among other things , that pollution caused by the discharge of
  certain individual substances which belong to eight families and
  groups ( known as List I substances ) must be eradicated in accordance
  with provisions laid down by the Directive .
  In particular , every discharge into the waters covered by the
  Directive which is liable to contain one of these substances requires
 prior authorization by the competent authority of the Member State
  concerned , which sets the emission standards .  These standards must
 not exceed the limit values adopted by the Council upon a proposal
 from the Commission , with the exception of those cases where quality
 objectives fixed by the Council are complied with .
 For the preparation of its initial proposals , the Commission con­
 vened a meeting of national experts on 14 June 1976 at which it was
 decided that priority should be given to the study of five substances
 they include mercury and its compounds .    This substance was chosen in
 view of its properties and the large quantities of discharges con­
 taining it .
 ---pagebreak--- At a second meeting held on 4 July 1977 » it was agreed , for limit
values , that the Corr, mission would first prepare a proposal concerning
chlor-alkali electrolysis plants , in view of the volume of discharges
in this sector , and that it would continue its work with a view to
presenting , as soon as possible , proposals for all mercury discharges
covered by Directive 76/464/EEC . At its meetings of 5 and. 6 December
1977 1 20 and 21 June and 13 and 14 November 1978 , "the group of
national experts advised the Commission on the preparation of this
proposal .
Aim of tho first proposal for a Directive
The purpose of the Directive ia to eliminate pollution caused by
discharges of mercury by chlor–alkali electrolysis plant into inland
                                                                  1
surface waters , territorial waters and internal coastal waters .
It accordingly contains provisions for the application of Directive
76/464 /EBC .
Direct discharges will have to meet the emission standards complying
with limit values which sire adopted primarily on the basis of
toxicity , persistence and bioaccumulation of mercury and which take
into account the best available technical methods .     The result will
be a significant reduction in these discharges . Additional stipu­
lations aim at bringing about a gradual reduction in pollution
caused by discharges from electrolysis plants which indirectly
introduce mercury into the aquatic environment .
A
   To protect groundwater against this type of pollution ( as well as
others ), the Commission has presented to the Council a proposal for
a. Directive on the protection of groundwater against pollution
caused by certain dangerous substance ( 0 J ITo C 37 » 14 February 1978
                                                                 Ρ·3 ).
 ---pagebreak---                                                             ί
                                    –  4 -
        The Member States will have to talce the appropriate administrative
         measures and carry out inspections which will enable "the Commission ,
        the Council and Parliament to "be adequately informed of the applica­
        tion of the Directive .
        If it transpires that the elimination of pollution of this type
        demands further measures as regards chlor–alkali electrolysis , the
        Commission will present appropriate proposals to the Council .
3.      Comments on the first proposal for a Directive
3.1 .    Limit values
         Chlor-alkali electrolysis may "be carried out in an isolated plant or
         on a site where there are several industrial activities .  The opera­
         tion of older plant causes much more complex pollution problems than
         that of new facilities .  The diversity of situations has made it
         necessary to define different limit values for different types of
         plant .  Differentiation as regards the maximum allowable concentra­
         tion in discharges is arrived at by means of variables whose value
         must be laid down for each plant .  The limit values proposed for
         maximum quantities vary with the date of entry into service of the
         plant and the production prooess .
3.1.1 . Maximum concentration
         The limit value expressed as a concentration relates to the point of
       ■ discharge into the receiving environment of the effluent discharged
         wholly or in part by electrolysis plant .  It is defined according to
         a formula whose significance for standard cases may be inferred from
         the following examples .
 ---pagebreak---   In an isolated plant all the mercury–contaminated, water has been in
  contact with the electrolysis installations . These are the process
  waters , used , for example , in condensation operations , equipment and
  site washing water , and rainwater . Contamination of these waters may
  be increased "by the leaching of mercury deposited on the ground or
                                                                   1
  in the drainage system after previous electrolysis operations .
  When a plant ha3 "been designed to use a minimum quantity of water ,
  its consumption may approximate to 700 l/t chlorine production
  capacity for manufacturing and equipment washing operations .
  If these waters make up the total effluent of a plant , the applica­
  tion of the formula of the maximum allowable concentration given in
  paragraph 1.1 of Annex I would require that this concentration should
  not exceed 700 jug mercury/l ; this would correspond to 0.49 S mercury/t
  chlorine production capacity , a value which is seldom complied with in
  existing plant . New plants to be built may need less process and
  washing water than 700 l/t chlorine , and mercury discharges authorized
  in this instance will therefore be less than 0.49 g/"t chlorine .
  To these discharges of mercury , however , there must be added those
  in rainwater run–off from roofs and the ground which has picked up
  particles of mercury emanating from chimney stacks or which have
  permeated the roof or walls of the electrolysis rooms . In a standard
, unit of recent construction , the total amount of wat er contaminated
  by mercury could be estimated at 2 m^/t chlorine production capacity.
  The concentration of 700 yug/l in the discharges then corresponds to
  a quantity of 1.4 g mercury/t chlorine .
    Leaching may even affect other waters . Mo special provisions are
  laid down for this case in the proposal for a Directive . Leaching of
  this kind therefore cannot be adduced as a reason for permitting a
  higher concentration of mercury in the discharges nor the emission of
  greater quantities of mercury by plant of a given capacity.
 ---pagebreak---                              - 6 -
Besides contaminated water , an electrolysis plant discharges other
water , in particular that used for cooling operations . In a standard
plant , the requirements for process , washing and cooling water are of
the order of 20 m^/t chlorine production capacity. By applying the
formula given in paragraph 1.1 of Annex I ,
                                         $
      C = 700 ~ a go ■ 70            mercury/l « 70 mg mercury/nr
This concentration corresponds to 1 .4 g mercury/t chlorine pro­
duction capacity, since the water requirements of the plant are
20 m /t chlorine , and      mg mercury/m x 20 m /t chlorine a 1,4 g
                     1
mercury/t chlorine •
Water consumption figures of the order of 20 m^/t chlorine are
 characteristic of plant which has "been in service for some years .
 Plant of more recent construction needs much more water , even if
 the volume of contaminated water is less than in older plants , as
 electrolysis is carried out at high temperatures to improve the yield .
 According to engineers * estimates , water requirements could be as
 high as 100 mVt chlorine production capacity in these plants .
 1
   Conversely, it is possible to deduce the concentration which would
   correspond , e.g. , to discharges of 0.5 g mercury/t chlorine and to
   water requirements of 20 m^/t Clg*
This would give : C x 20 m^/t chlorine = 0.5 g mercury/t chlorine
                   _     0.5 g mercury   __           / 3   rtr-
                   C   = –^-2        – a 25 mg mercury/m = 25 }Jg
                                 3                            mercury/l
 ---pagebreak---                                   - 7 -
  A new plant , within the meaning of the Directive , whose contaminated
  effluents were 2 m3/t chlorine and whose cooling water requirements
  were 98 m3/t chlorine should therefore comply with a concentration
  limit value obtained "by the formula :
                                2
              C = 700 x -xfyr        o 14 Pg mercury/l
 The discharges from this plant should also be compatible xvith a
  limit value expressed in terms of quantity ( see paragraph 3.1.2 ).
 Compliance with this value is an additional constraining factor
  affecting the maximum allowable concentration. If a new plant whose
 total effluent amounts to 100 m^/t chlorine may not discharge more
  than 0.5 g inercury/t chlorine , the maximum allowable concentration
  in the discharges would be obtained from the following formula :
              C x 100 m^/t chlorine =» 0.5 g mercury/t chlorine
              _      0.5 g mercury        _             / 3               /,
              C   = –IS                 B 5 nig mercury/ m = 5 ug mercury/ 1
                         100 m3
  If the effluent from electrolysis works ( including decommissioned
  plant ) is mixed with other waste before being discharged , the maxi­
  mum concentration is proportionately reduced , since , in the formula
  G =' 700        V refers to all the effluent discharged , whether or not
" it comes from electrolysis plant . Further , if the effluent which
  does not come from this type of plant contains mercury, it must not
  be taken into account for ascertaining whether the limit value is
                1
  complied with •
  1
    In practice , one could measure the concentration C * of these dis­
  charges before they are mixed and then make the following calculation :
        C'v * ,     v *: volume of effluent at the point of measurement
       – where           of C 1
                    V t volume of effluent at the point of discharge ,
                         and oheok whether:           m JQQJL
 ---pagebreak---                                      - 8 -
        The toxicity of mercury for the aquatic environment justifies such
        limit values . The lethal concentration for 50$ of a sample of young
        rainbow trout is reported to be 16 /og/l . With a dilution factor of
        8 , which is suggested as characteristic of good mixing conditions in
        flowing water , this would correspond to a concentration of 128 jag
        meroury/l in the discharges .
        It may "be feared that sub-lethal effects on aquatic organisms or
        their predators may "be caused "by much weaker concentrations and , in
        accordance with current practice in such cases , it would appear
        desirable to set a limit concentration^ in discharges of the order of
        10yug/l . If account were taken of the synthesis of methyl mercury
        in the environment , its accumulation in fish and its toxic effects
        on the nervous system of consumers , the conclusions reached could
        be even more stringent .
3.1.2 . Mrocinun cm runt it y
         In this proposal for a Directive , the limit values are expressed in
         concentration and in quantities per tonne of chlorine production
         capacity.    This variable was preferred to the tonne of chlorine
         produced because mercury pollution is largely independent of the
         rate of capacity utilization .   The timetable laid down takes account
         of the oost of the measures to be taken to collect and purify all
         the contaminated waters .   These operations are made particularly
            See R.H.W. Schubert : Appraisal of the ecological consequences
         ( ecotoxicity) of mercury discharges for the aquatic environment ,
         page 41 » report prepared for the Commission of the European
         Communities .
 ---pagebreak--- difficult "by the presence on -the ground and in the drainage system
of mercury discharged previously by the plant and likely to "be
leached .  This means that fairly long periods are needed in which
to meet the cost of cleaning the effluent of the mercury originating
in these residual deposits .
New plants do not have to be concerned with previous deposits and
an optimum water collection ajid drainage system can be designed
without conversion costs ; they can therefore comply with the limit
value of 0.5 g mercury/t chlorine without a transition period .
In 1977 a survey was made of 56 plants which electrolysed sodium
chloride and to a lesser extent potassium chloride, using mercury'' .
Of these plants , six producing about 1 5$ of the chlorine manu­
factured in mercury–cell electrolysis works , were using the " lost
brine " process .  The mercury concentrations in the discharges of
those works are similar to those found in electrolysis units using
the recycled brine , process , but , since the volumes of contaminated
water are many times greater than those discharged by a plant of the
same capacity using recycled brine , the quantities of mercury dis­
charged by a lost–brine plant are also many times greater than those
discharged by a recycled brine plant for the same production capacity,
The scale of the discharges of these plants means that a special
 effort must be made to achieve a relative reduction as already
 required by the competent authorities in the Member States concerned .
  * See Economist Intelligence Unit : The economic effects of pollution
 control measures on defined industrial sectors – mercury-discharging
 industries , p. 6 ; report prepared for the Commission of the
 European Communities .
 ---pagebreak---                                    - 10 -
      The Commission proposes that the entry into force of the Directive
      should prompt these establishments to make a new effort immediately
      and to take steps for a gradual reduction of their discharges .
      Under these conditions , the plants in operation at the date of noti­
      fication of the Directive will follow a special timetable which will
      take into account technical possibilities and the useful life of the
      various lost-brine electrolysis plants . To meet the timetable , some
      establishments will have to supplement or replaoe their water treat­
      ment facilities . This leeway will not be allowed to new plants .
3.2 . Authorizations
      Compliance with the limit values discussed in point 3.1 must be
      ensured by means of a system of prior authorization of discharges
      delivered by the competent authority of the Member State where the
      plant is situated . Each authorization must fix the emission stan­
      dards , which may not be less stringent than the limit values or the
      emission standards already in force on the date of entry into force
      of the Directive . This is to be interpreted as follows .
      If a standard is expressed as a concentration , it may be . applicable
      at the point of discharge , like the corresponding limit value , or
      upstream of that point . In the latter case , it must be possible to
      establish that the standard or maximum allowable concentration under
      the authorization is   not less stringent than the  limit value . This
      implies , first , that the standard applies to all  the waters contami­
      nated as a result of   eleotrolysis operations , so that a comparison
      can be made with the   limit value . Secondly , the maximum concentration
      of mercury must not exceed the value of 700 jig/l multiplied by the
      ratio between the volume of the contaminated waters flowing , through­
      out a given period , past the point or points designated in the
                                                        1
      authorization and upstream of a discharge point and the total volume
      of water flowing past this point ( or these points ) during that period.
      1
        As the standard applies to all the contaminated waters , this volume
        is equal to that of the waters used for the manufacture of electro­
        lysis products which are subsequently discharged .
 ---pagebreak---                               11 -
By way of exception , if "the standard applies to waters which, are to
undergo a further treatment of known efficiency , the value given
above may he divided "by the fraction which represents the residual
mercury content after treatment .
This may he formulated as follows t
vi    for a given period , the volume discharged at one point and
      corresponding :
      –  to the waters used in the manufacture of electrolysis pro­
         ducts and subsequently discharged ;
      –  washing waters used in the plant ; and
      –  precipitations forming part of the liquid effluent of the
         plant and contaminated "by mercury to a degree such that
         they may be purified if the best available technical
         methods are used ;
V:    for the same period , all the liquid effluents which come
      wholly or in part from the plant and which are discharged at
      the point under consideration ;    '
V
V »:
  1:  for the sane period , all the liquid effluents of the plant which
      flow past the point or points designated in the authorization
      and which arrive at the point of discharge under consideration }
ri
ΓI    the effioienoy of a meroury-removal unit downstream of the
      point or points designated in the authorization.   It is
      expressed as a figure between 0 and 1 ;
 ---pagebreak---                                    - 12 -
      ( l–r ): the fraction which represents the residual mercury content
               after treatment .
      If an emission standard is expressed as a concentration , it must
      comply with the forniular
      C a 700 y" if the standard is applicable at the point of discharge
      C » 700 -^7 if the standard is applicable upstream of the point of
                     discharge and downstream of the mercury–removal
                     facilities
      C »         y» if      standard is applicable upstream of the point
                     of discharge and of the mercury–removing facilities .
      The authorization fixing the emission standards may be granted for a .
      period of up to five years .   However , if an establishment installs
      a new electrolysis unit to which may be attributed direot mercury
      discharges distinct from those produced by the existing plant , this
      new unit must be treated as a new plant and the authorization adapted
      accordingly.   This provision virtually excludes the entry into
      service of electrolysis plant using the lost-brine process .
3.3 . Reduction of pollution caused by indirect discharges
      The mercury used in the electrolysis operations may leave the plant
      or remain there for a long period .- If it leaves the plant , it may
      be incorporated in a liquid , a gas or a solid .   In the first case ,
      there is a direct discharge within the meaning of the Directive and
      the mercury emitted must be covered by emission standards which meet
      limit values .
                                                4
      Airborne escapes of mercury outside the establishment and mercury
      incorporated in electrolysis products or in solid waste may cause
      water pollution , but the proposal does not lay down emission stan­
      dards for these cases .
 ---pagebreak--- Yet these losses are greater than those through direct discharges .
Moreover , mercury remaining in the plant for a long period – often
more than half the total consumption – may he discharged to the
environment , for example , when the installations are dismantled .
Control of mercury pollution of water therefore demands a global
approach .  First of all , the consumption of mercury must "be analysed
to obtain a clearer understanding of the components     and to assess
more accurately the risks to the environment .    The Member States will
then draw up plans for gradually reducing emissions which , taking
account of available technical resources , will lead to minimal dis­
charges of mercury into water .
Monitoring the application of the Directive
Mercury-cell electrolysis plants are in operation in all the Member
States except Ireland and Luxembourg .
Public concern about mercury pollution is prompting the authorities
and the industry to make special efforts to reduce mercury dis­
charges .  These efforts are coordinated under international conven–    •
tions to which the Community is a Contracting Party.
For these reasons', the monitoring of the application of the Directive
demands special measures .
The Member States are to supplement the measures laid down for the
 checking of compliance with discharge authorizations by studying
their effects in the zones affected .   Every five years , they will
 send to the Commission a report on all the measures taken pursuant
 to the Directive and on the reduction of pollution obtained through
 these measures .
   At the moment , the "unidentified losses " are of the same order of
   magnitude as the identified quantities used .
 ---pagebreak---                                  14 -
   The Con,mission may ask the Member States for farther information and
   will then report to the Council and to Parliament ; the Commission will
   propose any further measures which it considers would help eradicate
   mercury pollution.
   The Council may consider it useful to send the Commission ^ report to
   the international "bodies concerned with this type of pollution.
4. Aim of the second proposal for a Directive
   The aim of the Directive is to eliminate pollution of the aquatic
   environment caused "by mercury discharged from electrolysis plant lay
   obtaining compliance with quality objectives .
   These objectives are based on the toxicity of mercury, particularly
   for human beings , its persistence and its bioaccumulation in the
   aquatic environment . Qnission standards must be derived therefrom .
   Compliance with the standards and objectives must be checked in
   accordance with the procedure laid down in the Directive .
   To supplement the means of combating the pollution of the aquatic
   environment by mercury, provision is made for the gradual reduction
   of indirect discharges which can make it difficult to achieve the
   quality objectives .
   Finally , the proposal lays down that the Commission , after receiving
   information from the Member States , reports to the Council and to
   Parliament on the application of the Directive and presents proposals
   as provided for in Article 6(3 ) of Directive 76/464/EEC .
 ---pagebreak---                                     - 15 -
 5.      Cormorrts on the second proposal for a Directive
5.1 •    Quality objective ?;
5.1.1 . 'rit or
         In fresh water , the objective ia the guide value laid down in
         Directive 75/440/EEC concerning the quality required of surface water
         intended for the abstraction of drinking water : 0.5 ug/l *
        The guide value is selected in accordance with Article 4 of the
         Directive , which requires substantial improvements to the quality
         of water botween 1975 and. 1985 * The quality objective must be
         complied with by 1 July 1983 *
        In estuaries and coastal waters , the quality objective is set at
        0.05 ug/l . The selection of /this value is a guarantee against
        increased contamination of the waters in question. Furthermore , it
        incorporates adequate safety coefficients for the marine species
                                                            1
        about which the Commission possess scientific data .
5.1.2 . Fish
        The protection of fish species would be guaranteed by the quality
        objectives adopted for water . However , those who consume the most
        fish need specific protection .
        1
           These data are given in the report "Appraisal of the ecological
           consequences ( ecotoxicity) of mercury discharges for the aquatic
           environment ", prepared by Prof. R.H.W. Schubert for the Commission
           of the European Communities .
 ---pagebreak---                                - 16 -
The quality objective adopted is 0.3 mg mercury/kg wet fish flesh .
It applies to a representative sample of the fish consumption of
persons exposed to substantial risk .     The first symptoms of mercury
poisoning may be said to occur as follows :
WHO considers that in the most sensitive subjects the effects of
methyl mercury can be detected as from a blood concentration of
20 to 50 ^g/100 ml . By regression analysis it can be found that
this concentration corresponds at least to a dally intake of methyl
mercury of 3.5 Jig/kg body weight for a person of 70 kg.
This finding is confirmed by direct estimates of the intake of methyl
mercury likely to cause disorders in human beings ; it is thought to
be equal or greater than 3 jag/d/kg^, which corresponds to 210 jJg/d.
The consumption of other foodstuffs besides fish does not lead to an
ingestion of mercury greater than 5 ps/^ m
Drinking water consumed cannot contain a mercury content of over
2 pg/d , if the Community Directives on this subject are applied .
The ambient air carries no more than 50 "S mercury/m^, equivalent       '
to an exposure of 1 ^ig/d^. If , to simplify the calculations we
assume that exposures of these three types are entirely due to
methyl mercury which the organism assimilates to a rate of 100$
 Λ
   WHO . Environmental Health Criteria 1s Mercury ; Geneva , 197° .
 2
   WHO , op . cit ., pp 80 and 118 .
 ^ See Department of the Environment , Environmental Mercury and Man,
   Pollution Paper Ho . 10 , HMS0 , London , 1976.
^ See WHO , op. cit ., pp 64 and 65.
 ---pagebreak---                                 - 17 -
  a consumer sensitive to methyl mercury could ingest 200 }ig/d of this
substance "before running the risk of suffering toxic effects , provided
                                                                 «1
that he is not exposed to mercury "by reason of his occupation -.
If the fish consumed contains 300       kg mercury , a consumer could
ingest two-thirds of 1 kg/d "before running a risk of nervous dis-
                                                    2
orders , the probability of which is less than 5/i> •
The highest daily consumption rates recorded do not exceed $00 g^.
The quality objective adopted would therefore be adequate to protect
consumers against the risks , as currently identified^.
However , the Commission could ohange this opinion if new toxicological
effects due to the ingestion of mercury, or biochemical or physio­
logical damage for intakes below the toxicity threshold were
discovered ^.
1
   The main consumers of mercury are fishermen who are not exposed
   to risks of poisoning by virtue of their occupation , as distinct
   from those oonnected with their consumption pattern .
2
   See WHO , op . cit ., p. 66.
? See WHO , op . cit ., p. 118.
^ In Minamata Bay the mercury content of the fish flesh has reached
   50.000 yug/kg, see DOS op. cit ., p. 7 »
^ WHO has drawn particular attention to this point ; see WHO op.
   oit ., p. 26 .
 ---pagebreak---                                           - 18 -
5.1 . 3 . Sediments and r.'iolluncn
          The mercury content of sediments is important for the protection of
          the environment , particularly "because they are thought to "be the site
          where bacteria synthesize methyl mercury passing through the food
                 1
          chain • It is not at present possible to propose a maximum mercury
          content for sediments , but in principle it can be ascertained whether
          the content is increasing or not .
          It may be difficult to obtain this information , as the movements of
          sediments over a period of time are likely to prevent the results
          obtained boing comparable . In this case it would be preferable to
          observe sedentary organisms which accumulate mercury, and this is
          why the proposal for a Directive includes this possibility.
5.2 .     Coi..nlip.nce with the objectives        ■
          The proposal for a Directive provides that the quality objectives are
          to be attained by means of compliance with emission standards for
          direct discharges and the implementation of programmes to reduce
          pollution caused by indirect discharges .
          This dual approach is necessary, as indirect discharges are
          responsible for a large proportion of mercury pollution. To ignore
          them would make it very difficult to ensure compliance with the
          objectives .
             See WHO , op . cit .. pp . 5® "to 5°*
 ---pagebreak---                                      - 19 -
5.3 . Honitonrvr procédure nnd rcnort
      For each quality objective , the proposal stipulates :
              ( i ) the preliminary research to he carried out :
            ( ii ) sampling frequency;
          ( iii ) the reference method of analysis ;
            ( iv ) the method of expressing and interpreting the results .
      The information which the Member States applying the Directive will
      supply every five years on the implementation of the monitoring
      procedure will enable the Commission to prepare the report to the
      Council and the proposals referred to in Article 6(3 ) of Directive
      70/464 /EBC .
      The proposal provides that the Commission will also report to
      Parliament on the application of the Directive .      The importance
      which public opinion attaches to mercury pollution makes this report
      particularly advisable .
6.    Consultation of Parliament and of the Economic and Social Committee
      As these proposals for Directives are based on Article 6 of
      Directive 76/464/ESC1 consultation of Parliament and of the Economic
      and Social Committee is not required .     However , the Commission con­
      siders , in view of the politioal importance of the proposals , that
      they should be submitted to both these Institutions .
 ---pagebreak---                                - 20 -
                 Proposal for a Council Directive on "the
                 limit values applicable to discharges of
                 mercury into the aquatic environment "by
                 the chlor-alkali electrolysis industry
THE COUNCIL OP THE EUROPEAN COMMUNITIES ,
Having regard to Council Directive 76 / 464 / EEC of 4 May 1976 on pollu­
 tion caused by certain dangerous substances discharged into the aquatic
                                 1
  environment of the Community , and in particular Article 6 thereof ,
                                                      2
Having regard to the proposal from the Commission t
Having regard to the opinion of the European Parliament"^,
                                                                         4
 Having regard to the opinion of the Economic and Social Committee ,
 Whereas , in order to protect the aquatic environment of the Community
 against pollution "by certain dangerous substances , ; Art i c le 3 of Direc­
tive 76 / 464 / EEC provides for a system of prior authorization laying
down emission standards for discharges of the substances falling with­
 in List I contained in the Annex thereto , and Article 6 thereof pro­
vides that limit values shall be laid down for such emission standards ;
   OJ No L 129 of 18 May 1976, p. 23 .
 2
3
4
 ---pagebreak---                                 - 21 -
Whereas mercury and its compounds are included m "the List ;
VJhereas that Directive also provides for the establishment of quality-
objectives , and whereas these have been laid down in Council
Directive                ;
Whereas , since the pollution caused by discharges of mercury into water
arises principally from the electrolysis of alkali chlorides , in the
first instance Limit values should be established for this industry and
its discharges made subject to prior authorization ;
Whereas provision should be made for the Member States to fix emission
standards and time–limits which are no less stringent than the limits
laid down by the Council ;
Whereas the Member States should take the requisite measures to ensure
that discharges and their effects are monitored ;
   Whereas it is important that the Member States should take measures to
reduce pollution caused by mercury discharged indirectly into the
 aquatic environment ;
Whereas , since groundwater is to be the subject of a specific Directive ,
 it is excluded from the scope of this Directive ;
 Whereas it is important that the Council and the European Parliament
 be kept regularly informed as to the operation of the Directive,
 HAS ADOPTED THIS DIRECTIVE ,
  1
 ---pagebreak---                                      - 22 -
                                   Article 1
1.  The purpose of -this Directive is to lay down /for the chlor-alkali elec­
   trolysis industry the limit values which emission standards must not ex­
    ceed and the time-limits for implementation in respect of discharges of
    mercury ana mercury compounds into the aquatic environment . ~
2.  This Directive applies to the waters referred to in Article 1 of
    Directive 7 6/4 64/EEC , with the exception of groundwater .
                                  Article 2
    For the purposes of this Directive :
    ( a)  "limit value " means :
          -   the maximum allowable concentration of mercury and its compounds
              in direct discharges ;
          -   the maximum quantity of these substances whose discharge has
              "been authorized , in relation to the production capacity of the
              establishments in question ;
    ( b ) "discharge " means the introduction "by an industrial establishment
          of mercury or its compounds into the waters referred to in
          Article 1(2 );
    (c)   "direct discharge " means any discharge which has not beforehand
          been :
          -   borne through the air outside the industrial establishment , or
              incorporated into the products or wastes ;
    (d)   " indirect discharge" means any disoharge which is not a direct
          discharge ;
 ---pagebreak---                                - 23 -
(•)  " industrial establishment " means any plant where alkali chlorides
     are or have been electrolysed and which is " in a position to make direct
     discharges of mercury which , may be directly attributed to it ;
(D   " existing establishment " means an industrial establishment in
     operation on the date of notification of this Directive ;
(g ) "new establishment " means an industrial establishment brought
     into operation after the date of notification of this Directive .
                            Article 3
The emission standards , the time–limits for compliance and the sampling
frequencies laid down in the authorization referred to in Article 3 of
Directive 76/464/EEC shall comply with the limits given in Annex I to
this Directive .
The methods of analysis laid down in the authorization shall comply
with the reference method of analysis given in Annex II to this
Directive . Where the use of other methods of analysis is authorized ,
such methods shall comply with the detection limit , precision and
accuracy laid down in Annex II .
No authorization may be granted for a period of more than five years .
                            Article 4
The Member States shall draw up programmes for the gradual reduction
and eventual elimination of pollution caused by indirect discharges
into the waters referred to in Article 1(2 ). These programmes shall
provide for an analysis of the consumption of mercury by industrial
establishments and shall lay down intermediate objectives to be
reached seven years after notification of this Directive .
 ---pagebreak---                               Article 5
The Member States shall keep the entire zone affected by the discharges
from industrial establishments under surveillance and shall monitor
the effects of these discharges . In the event of transfrontier pol­
lution affecting more than one Member State , the States concerned
shall act in concert with a view to adopting appropriate control
measures and shall forthwith inform the Commission thereof .
                              Article 6
Every five years following notification of this Directive , the Member
States shall draw up and send to the Commission a report on the
reduction of pollution caused by discharges of mercury into the aquatic
environment by the chlor–alkali electrolysis industry.
The Member States shall , in accordance with Article 13 of Directive
76/464/1100 , supply the Commission , at its request , with any necessary
additional information specifically concerning :
– the authorizations granted in accordance with Article 3 and in
   particular the emission standards , the monitoring procedures
   introduced , the sampling frequencies and the methods of sample
   analysis ;
– the programmes for the gradual reduction of the pollution in
   question , drawn up pursuant to Article 4 »
– the results of the surveillance and monitoring carried out in
   accordance with Article 5 *
The Commission , on the basis of the information it has received pursuant
to this . Article , shall report every five years to the Council and to
the European Parliament on the . _ operation of this Directive and , if
necessary, shall place appropriate additional proposals before the
Council .
 ---pagebreak---                                     25 -
                                Article 7
1. The Mem"ber States shall , wzthm two years of the date of notification
   of this Directive , "bring into force the measures necessary to comply
    therewith            and shall forthwith inform the Commission thereof .
2. The Member States shall communicate to the Commission the texts of the
   provisions of national law which they adopt in the sector covered "by
   this Directive .
                                Article 8
   This Directive is addressed to the Member States .
                                     Done at
                                     For the Council ,
                                     The President
 ---pagebreak---                                  ATOTEX I
                      Limit values and time–limits
The limit values and time–limits within the meaning of Article 1(1 ) are
as follows :
Maximum concentrations
At each point of discharge the average monthly concentration of the
mercury emitted as a result of chlor–alkali electrolysis operations may
not "be greater than that given by the formulas
                              c - 700 j
where C ■= maximum allowable concentration in pg mercury/l
where C
       v
       V  «■
          «■ volume discharged at a specific point and corresponding,
             for the month in question, to :
             ( a ) the water used in the manufacture of the products of
                   electrolysis and subsequently discharged ,
             ( b ) the washing water used in the plant , and
             ( c ) the precipitations which form part of the effluent
                   from the plant and which are contaminated by mercury
                   to a degree such that they can be purified if the
                   best available technical means are used *
       V  »  all the effluent arising , in whole or in part , from plant
             over the same period and which is discharged at the point
             in question.
In order to check compliance with the limit values , measurements must
be taken at least once a day from representative discharge samples .
 ---pagebreak---                                          27 -
      The sampling method must allow for instantaneous values for concentra­
      tion and flow in such a way as to ensure that the samples are
      representative^.
      The average monthly concentration must he calculated on the basis of
      the arithmetic mean of the daily average concentrations *
1.2 . The provisions of paragraph 1.1 apply to establishments existing at
      1 July 1983 . They apply to new establishments :
      – two years after the date of notification of the Directive ;
      –    as soon as the establishment is brought into service if this
           occurs after that date .
2.    Maximum quantities
2.1 . Existing recycled–brine plants
      ouch
      ouch   plants may not discharge , on an average monthly basis , directly
      into the waters referred to in Article 1 ( 2 ) more than :
      into
      ( a) 1.5 g mercury/t chlorine at 1 July 1983
      ( b) 1 g       mercury/t chlorine at 1 July 1986
      ( c ) 0.5 g mercury/t chlorine at 1 July 1989 .
      In this and subsequent paragraphs the expression "t chlorine" refers
      to the production capacity.
      1
          It is accepted that the analysis every 24 hours of a sample
          constituted in proportion to the flow meets this requirement .
         The concentration measured may be regarded as a daily average .
         Hourly analysis of samples coupled with a flow measurement is also
          permitted . Daily concentrations must then be calculated as the
          average of the concentrations measured , weighted by the flow
          readings .
 ---pagebreak---                                        - 28 -
2.2 . Exintirvr lost-brine T)lant3
        Such plants may not discharge , on an average monthly "basis , directly
        into the waters referred to in Article 1 ( 2 ) more than :
        ( a ) 8 g mercury/t chlorine at 1 July 1983 ;
        ( b ) 5 g mercury/t chlorine at 1 July 1986 ;
        ( c ) 2.5 g mercury/t chlorine at 1 July 1989 .
2.3 . -Tcvf establishments
        Such establishments may not discharge , on an average monthly basis ,
        more than O .5 g mercury/t chlorine directly into the. waters referred
      . to in Article 1(2 ):
        –    two years after the date of notification of the Directive , or
        -    as soon as the establishment is brought into service , if this
             occurs after that date .
 ---pagebreak---                          ÂOTJEX II
               ReFerence method of analvsis
For the purposes of Article 3 , "the reference method of analysis is
flameless atomic absorption at 0.2537 um » after pre–oxidation of the
unfiltered sample and reduction of the mercury ions Hg ( II ) by
stannous chloride (SnCl^) and entrainiaent of the mercury vapours.
– Detection limit* : 0.0001 rag/l Hg
– Précision*          ï + 15$
– Accuracy*           I 4- 30$
*  cf . the definitions given in the proposal for a Council
Directive on the methods of measurement and frequencies of
sampling and analysis of the parameters of the quality required
of surface water intended for the extraction of drinking water in
the Member States (0 J No C 208 , of 1 September 1978)*
 ---pagebreak---                                  - 30 -
            Proposal for a Council Directive on the quality
            objectives for the aquatic environment into which
            mercury is discharged lay the chlor–alkali
            electrolysis industry
 THE COUNCIL OP THE EUROPEAN COMMUNITIES ,
 Having regard to Council Directive 76 / 464 / EEC of 4 May 1976 on pollution
 caused by certain- dangerous substances discharged into the aquatic en^
                              •1    *
 vironment of the Community , and in particular Article 6 thereof /
                                                      2
 Having regard to the proposal from the Commission f
 Having regard to the opinion of the European Parliament ^,
 Having regard to the opinion of the Economic and Social Committee^,
 Whereas , in order , to protect the aquatic environment of the Community against
 pollution by certain dangerous substances. Article 3 of Council Directive
 76/464/EEC provides for a system of prior authorization laying down
 emission standards for discharges of the substances falling within List
 I contained in the Annex thereto , and Article 6 thereof provides that
  limit values shall be laid down for such emission standards and also
 quality objectives for the aquatic environment affected by these
 substances ;                     ,
   OJ No L 129 of 18 May 1976 , p. 23
 2
.3
 4
 ---pagebreak--- Whereas mercury and its compounds are included in the List :
                              1,
Whereas Council Directive ••• lays down       limit values for dis­
charges of mercury into the aquatic environment ;
Whereas , although the Member States are required to apply the limit
values , they may in certain cases employ a system of quality
objectives ;
Whereas a monitoring procedure should be instituted to enable the
Member States to demonstrate that the quality objectives are
complied with ;
Whereas , since the pollution caused by discharges of mercury into
water arises principally from the electrolysis of alkali chlorides ,
quality objectives should , in the first instance , be laid down for
the aquatic environment into which mercury is discharged by this
industry and these discharges should require prior authorization .
Whereas , in order to attain the quality objectives , Member States
should lay dovm emission standards in the authorizations granted and
whereas the Member States should take steps to reduce pollution caused
by mercury discharged indirectly into the aquatic environment ;
Whereas it is important that reports be prepared on cases where the
system of quality objectives has been applied ;
Whereas , since groundwater is to be the subject of a specific Directive ,
it is excluded from the scope of this Directive ,
HAS ADOPTED THIS DIRECTIVE :
1
 ---pagebreak---                              Article 1
The purpose of this Directive is to lay down quality objectives for
the aquatic environment into which mercury is discharged lay the chlor–
alkali electrolysis industry and to institute a monitoring procedure .
This Directive applies to the waters referred to in Article 1 of
Directive 76/464/EBC > with the exception of groundwater .
                             Article 2
For the purposes of this Directive :
( a ) "quality objective" means the maximum allowable concentration
      of mercury or its compounds in the aquatic environment concerned ;
( b ) "discharge " means the introduction by an industrial establish­
      ment of mercury or its compounds into the waters referred to in
      Article 1(2 );
( c ) "direct discharge" means any discharge which has not beforehand
      been :
             borne through the air outside the industrial establishment ;
             or
             incorporated into the products or waste ;
( d ) "indirect discharge" means any discharge which is not a direct
      discharge ;
( e ) "industrial establishment " means any plant where alkali
      chlorides are or have been electrolysed and which is in a position
      to make direct discharges of mercury which may be directly
      attributed     to it .
 ---pagebreak---                                 - 33 -
                               Article 3
   The Member States shall draw up programmes for the gradual reduction
   and eventual elimination of pollution caused Toy indirect discharges
   into the waters referred to in Article 1(2 ).
   These programmes shall provide for an analysis of the consumption of
   mercury "by industrial establishments and shall lay down intermediate
   objectives to be reached seven years after notification of this
   Directive .
                                            3
                              Article 4
   Where the area liable to be affected by the discharges is a trans-
   frontier area , the Member States concerned shall consult one another
   on the implications arising from the application of this Directive
   and shall forthwith inform the Commission thereof .
                              Article 5
1. Every five years following notification of this Directive , the
   Member States shall draw up and send to the Commission a report on
   the reduction of pollution caused by discharges of mercury into the
   aquatic environment by the chlor–alkali electrolysis industry.
2. The Member States shall , in accordance with Article 13 of Directive
   76/464/E0C , supply the Commission , at its request , with any necessary
   additional information specifically concerning :
   - the authorizations granted and in particular the emission
      standards ,
   - the implementation of the monitoring procedures ,
   - the programmes for the gradual reduction of the pollution in
      question , drawn up pursuant to Article 3 ,
 ---pagebreak--- –  the application of the Directive to transfrontier areas , in
   accordance with Article 4 *
The Commission , on the "basis of the information it has received
pursuant to this Article , shall report every five years to the
Council and the European Parliament on the operation     of this
Directive and shall place appropriate proposals "before the Council ,
on which the latter shall act pursuant to Article 6(3 ) of
Directive 7 6/464/EEC •
                            Article 6
The Member States shall , within two years of the date of notification
of this Directive , bring into force the measures necessary to comply
therewith   '       • and shall forthwith inform the Commission thereof .
                                           J
The Member States shall communicate to the Commission the texts of
the provisions of national law which they adopt in the sector covered
by this Directive .
                            Article 7
This Directive is addressed to the Member States .
                                   Done at
                                   For the Council ,
                                   The President
 ---pagebreak---                              ΛΙΓΝΕΧ I
                       Qualitv   objectives
* The following stipulations apply in the areas affected "by discharges
  from industrial establishments :
  1.   The concentration of mercury in waters must not "be more than
       0.5 jug/l within the freshwater limit . It must not he more
       than 0.05 >Jg/l beyond this limit .
  2.   The mercury content in the flesh of fish living beyond the
       freshwater limit must not exceed 0.3 mg/kg wet weight .
  3.   The mercury content in sediments or in a characteristic mollusc
       must not increase with the passage of time .
  4.   These quality objectives must be attained by 1 July 1983#
 ---pagebreak---                                  - 36 -
                                AN1J3X II
                          Monitorirvt nrocedure
I    Compliance with the quality objectives laid down in point 1 of
     Annex I must "be monitored as follows :
  1. For each geographical area affected by the discharges three zones
     must be demarcated :
     A    The immediate mixing zone : zone in the immediate vicinity of
          the discharge point where the degree of dilution is very slight ;
     B    Dispersion zone : zone more remote from the discharge point
          characterized by a higher degree of diffusion and greater
          discharge dilution ;
     G    Zone unaffected by the discharges : zone where the effects of the
          discharges are not detectable .
  2. Samples must be taken over a network of points located in such a way
     that the samples taken are statistically representative of the
     quality of the waters throughout zone B.
     The concentration of mercury must be determined at each sampling point
     and the dilution factor for the mercury discharged by the industrial
     establishment ^ ) concerned must be estimated by dividing the con­
     centration in the discharges by the highest concentration measured
     in the zone .
  3. The discharge standard must be fixed or reviewed in the light of the
     quality objective and of the concentrations measured , bearing in mind
     the possibilities of additional mercury discharges in zone B during
     the period covered by the authorization .
 ---pagebreak---  In order to check compliance with "the standard , measurements must "be
 taken at least once a day from representative discharge samples .
 The sampling method must allow for instantaneous values for con­
 centration and flow in such a way as to ensure that the samples are
 representative .  The reference method is that defined in Annex II
 to the proposal for a Council Directive on the limit values applicable
 to discharges of mercury into the aquatic environment "by the chlor–
 alkali electrolysis industry.
 Compliance with the quality objective must he estimated daily "by
 dividing the concentration measured in the discharges "by the dilution
 factor .
.The mercury concentration in the receiving waters nrust "be measured
 directly every six months and the dilution factor re–estimated on
 that occassion .
 If the value measured is more than 0.4 pig/l within the freshwater
 limit and 0.04 >ig/l "beyond this limit , the measurements must "be taken
 more frequently.
 Measurement of the mercury concentration in the receiving waters must
 be carried out from an unfiltered sample .    The reference method of
  analysis is that referred to in point 4 » and is carried out after
 the mercury has been concentrated in carbon tetrachloride in the
  form of dithizonate and extracted .
  Detection limit : 0.004 pg mercury/l
  Precision         s + 15f°
  Accuracy          : + 30$
 ---pagebreak---                                                                 ι
                                  - 38 -
II     Compliance with the quality objective laid down in point 2 of
       Annex I must "be monitored as follows :
    1. In each of the areas in the vicinity of an industrial establishment
       which makes discharges "beyond the freshwater limit , the consumption
       pattern of the main fish–eaters is to "be studied in order to draw
       up a typical diet .
    2. A sample of fish muscle tissue    reflecting the pattern of the
       typical diet is to "be taken every six months from each zone aul
       this sample is to be analysed .   If the value measured exceeds
       0.25 /Jg/kg , the measurements must be taken more frequently.
    3. The reference method of analysis is that referred to in point 1 .4
       and is carried out after thie sample ha3 been taken up in solution
       with nitric acid .
       Detection limit    : 10 jag mercury/kg
       Precision          : + 5$
       Accuracy           : + 15$
III    Compliance with the quality objective laid down in point 3 of
       Annex I must be monitored as follows :
    1. In each of the areas in the vicinity of an industrial establish­
       ment , the competent national authority decides whether it is
       preferable to select sediment or a specific mollusc as the
       indicator of changes in the mercury content with the passage of
       time in the area concerned .
    2. Samples must be taken every twelve months of the target selected
       such that the samples are statistically representative of the
       area in question .
 ---pagebreak---                                                           a
                             - 39 -
3. The reference method of analysis is "that referred, to in point
   1.4 and is carried out after :
   –  digestion with nitric acid in the case of sediment ;
      the results must "be expressed in mg mercury/kg dry matter , and
   –   separation of the solid and liquid substances and digestion
      with nitric acid in the case of molluscs .
      The analysis must be carried out on the solid substances .
   Detection limit i 10 pg mercury/kg
   Precision          : + 5%
   Accuracy           : + 15%
4. In order to ensure that the quality objective is maintained , the
   results of the measurements carried out over a given period must
   not , on average , be significantly higher than those obtained the
   previous year .
   The significance threshold is 9