Paper for the 4th meeting of the Task Force on Heavy Metals under the UNECE
Convention on Long-range Transboundary Air Pollution, Vienna 6-8 June, 2007
Exploration of possible options for the reduction of HM from a
technical point of view, including costs and benefits
Maarten van het Bolscher, Johan Sliggers and Jean-Paul Hettelingh
1. Introduction
At the 24th Executive Body meeting in December 2006 Parties to the Heavy Metals
(HM) Protocol agreed that the first review of the Protocol had been completed. Also,
the EB endorsed the work plan of the Task Force for 2007. Main items in this work
plan are:
(a) Explore from a technical point of view options for further reducing the emissions
of the heavy metals listed in Annex I. Advantages and disadvantages of the options
will be compiled and
(b) Assess quantitative and, where this is not possible, qualitative information on
health and ecosystem benefits of further measures to reduce emissions of heavy
metals listed in Annex I.
Parties to the Protocol at the EB felt that more insight was necessary on the various
options to reduce emissions of heavy metals further including their costs and
(qualitative) benefits before they conclude on a possible revision of the Protocol. This
paper addresses possible options for the further emission reduction of heavy metals.
For a number of options the emission reduction, the costs involved with those options
and their effects, expressed as exceedances of critical loads, have been compiled. The
basis of the compilation is formed by two studies and reports:


Study to the effectiveness of the UNECE Heavy Metals (HM) Protocol and
cost of possible measures, Phase II: Estimated emission reduction and cost of
options for a possible revision of the HM Protocol (Visschedijk et al., 2006)
Heavy Metal Emissions, Depositions, Critical Loads and Exceedances in
Europe (Hettelingh et al., 2006).
Both reports have been presented at the Working Group on Strategies and Review in
September 2006 and will be presented at the Task Force on HM in Vienna in June
2007. The reports can also be found on the home page of the Task Force on HM.
In this paper, which deals with the European case only, you will find the description
of the options for the further reduction of heavy metals in chapter 2. The compilation
on the emission(reduction)s, costs and exceedances per option is given in chapter 3.
This chapter also presents and discusses results. The paper concludes with a more
general discussion on a possible revision of the HM Protocol in chapter 4.
2. Options for the further reduction of heavy metals
Seven options have been explored starting from the full implementation of the current
1998 HM Protocol. The option that all countries fully implement the current HM
Protocol is to be seen as a baseline and forms the minimum case. The maximum case
is when additional measures for all three priority metals at new and existing sources
are taken. Figures on emission (reductions), costs and exceedances have been
compiled for all European countries in the EMEP domain. In the various options
distinctions are made between EU+ (EU25 countries plus Norway and Switzerland.
Paper for the 4th meeting of the Task Force on Heavy Metals under the UNECE
Convention on Long-range Transboundary Air Pollution, Vienna 6-8 June, 2007
Note: When the underlying studies, that have been used for this paper, were
performed Bulgaria and Romania were not part of the EU yet) and non-EU countries.
Two main sets of measures are explored, one for dust related mesures that reduce
emissions of Cd and Pb and one for measures that reduce emissions of Hg. Other
distinctions between scenarios are whether measures are taken for new stationary
sources only or for both new and existing stationary sources. Product measures on Hg
as foreseen in the EU have not been taken into account.
For the following seven options figures have been compiled:
1. Full Implementation HM Protocol.
In this first option all European countries ratify and implement the 1998 HM Protocol.
2. Additional measures Cd and Pb new.
In this option all countries fully implement the HM Protocol and take additional
measures at new stationary sources for Cd and Pb. This means in effect that they take
dust related measures at all relevant significant sources.
3. Additional measures Cd and Pb new. The EU(25)+ also existing.
All countries take dust related measures at new stationary sources. The EU+ countries
also take these measures at existing stationary sources.
4. Additional measures Cd and Pb new and existing.
All countries take dust related measures at new and existing stationary sources.
5. Additional measures Cd and Pb new and existing. The EU(25)+ also additional
measures Hg new.
All countries take dust related measures at new and existing stationary sources. The
EU(25)+ countries also take Hg measures at new stationary sources.
6. Additional measures Cd and Pb new and existing. Additional measures Hg new and
the EU(25)+ also for existing.
All countries take dust related measures at new and existing stationary sources. All
countries take measures for Hg at new sources and the EU(25)+ countries also take
measures at existing stationary sources.
7. Additional measures Cd and Pb new and existing plus additional measures Hg new
and existing.
All countries take measures to reduce emissions of dust and Hg at new and existing
stationary sources.
3. Emission, costs and exceedances of the options to reduce HM emissions
Options
The starting point for the identification of possible options for the reduction of HM
emissions is the selection of sources based on the contribution to the 2020 HM
emissions. For 2020 full implementation is assumed (all European UNECE countries)
of the current HM Protocol and implementation of all foreseen autonomous
developments. The reduction will be discussed via a possible strengthening of the
Protocol and subsequent quantification of emission reductions and costs.
As described in chapter 2, we have identified seven different possible options for
strengthening of the Protocol on HM. Option 1 can be seen as the baseline scenario,
where no additional measures have been included. Step-wise, additional measures are
shown for two country groups, EU(25)+ and non-EU(25)+. Finally Option 7 includes
all
additional measures.
Paper for the 4th meeting of the Task Force on Heavy Metals under the UNECE
Convention on Long-range Transboundary Air Pollution, Vienna 6-8 June, 2007
The possibility for further reductions of HM emissions has been explored by selecting
new emission limit values (ELVs) based on information submitted by IFARE to the
Task Force on Heavy Metals for updating the Annex V of the Protocol. These more
strict ELVs could replace those that are currently in the Protocol upon a possible
revision.
Emissions
The projected emissions of Cd, Hg and Pb in 2020 and the reduction percentage in
relation to the ‘baseline’ Option 1 are shown in table 1. Within the analysis a
distinction has been made between the EU 25 member states plus Norway and
Switzerland (EU(25)+) and the other European UNECE countries (non-EU(25)+).
The projected emissions for 2020 for the EU(25)+ assume implementation of the
IPPC Directive as autonomous policy. This implies that in 2020 all major industrial
sources of air pollution will use technologies equal or equivalent to BAT as described
in the IPPC BREF Documents.
Costs
Besides the emissions and emission reduction for Cd, Hg and Pb in 2020 as a result of
the different options, table 1 shows the costs. The costs of the options are shown as
incremental costs, calculated as additional costs on top of the costs of a full
implementation of the present HM Protocol. This implies that the differences
between the costs of the present ELVs and the adjusted ELVs will be calculated.
Within the TNO study, costs have been described as the modification costs of an
installation without distinguishing new and old installations. Since measures for only
new installations could be an option we have made a rough estimation of the
emissions, costs and exceedances when taking this into account.
The estimation is based on the assumptions that installations have a life expectancy of
30 years, that the installations will be renewed gradually, and that this option will be
applied starting from 2010. This implies that costs will increase slowly and emissions
reduces slowly. For new installations measures have to be taken. In 2020 we estimate
that 1/3 of the installations will be renewed making total annual costs in 2020 1/3 of
the costs necessary to apply the measure to all installations at that time
This estimation is of course a rough one and has its limitations. When building a new
installation for example, new technologies will be used and costs and emissions could
be much lower as described here. On the other hand the additional costs will be
relatively small regarding the total costs of new installations. The cost figures and
emissions within the grey rows of table 1 must therefore be seen as a conservative
estimation.
It should be mentioned that ex-post evaluations of costs made show that these costs
are a factor of 2 to 10 lower compared to the the ex ante calculated costs.
Exceedances
Exceedances are computed by comparing critical loads with atmospheric depositions.
Depending on the endpoint, exceedances can be computed to identify the risk for
human health or the risk for ecotoxicological effects (see Hettelingh et al., 2006).
However, the results described in this report focus on the most sensitive endpoint.
Paper for the 4th meeting of the Task Force on Heavy Metals under the UNECE
Convention on Long-range Transboundary Air Pollution, Vienna 6-8 June, 2007
Thus, the lowest critical load has been chosen if critical loads have been computed for
both endpoints for any single ecosystem point in the European database.
In this paper the risk of impacts caused by the deposition of Cd, Pb and Hg has been
expressed as (a) the Area at risk, and (b) the Average Accumulated Exceedance
(AAE). Table 1 (last column) shows the percentages of areas at risk of health or
environmental effects caused by deposition of the heavy metals for the year 2020.The
area at risk is computed as the percentage of the European ecosystem areas (forest
soils, grassland, arable land or freshwaters) as submitted by National Focal Centres
(forest soils otherwise) of which the critical load of a metal is exceeded by the
deposition of this metal. The AAE is the ecosystem area-weighted sum (in g ha-1 yr-1)
of the individual exceedances (deposition minus critical load, with zero for nonexceedance) of all ecosystems in a region (see Hettelingh et al., 2006, pp.38).
As any other statistic, an AAE can be computed for Europe, a country, a (sub-)
region, an EMEP grid cell, or ecosystems within and EMEP grid cell. In this paper
both the Area at risk and the AAE are computed for EU25 Member States plus
Switzerland and Norway, the non-EU(25)+ countries under the LRTAP Convention
and for the whole of Europe (EMEP domain).
Results
Table 1 gives an overview of the options and the related emissions, costs and areas at
risk. Besides grey marked rows, the options show a step by step increase in emission
reduction. The reason for the decrease in emission reduction (grey rows), instead of an
increase, is due to the fact that by implementing the specific Hg measures a few dust
measures become redundant. Those dust sources (Cd and Pb emisions) will also be
covered for only 1/3 within this scenario by the Hg measure, because the dust measure
has become redundant compare to a full implemented Hg measures. Since only 1/3 of
these Hg measures will be applied in these ‘grey rows’, there will be more emission
from the dust sources (Cd and Pb emission). Those installations that aren’t renewed
yet within this scenario, but are subject to be renewed within the future will therefore
have a higher emission for Cd and/or Pb for some sources.
As can be seen the emission of Hg is poorly mitigated by generic dust emission
reduction measures (Option 1 to 4). In general, measures under the HM Protocol focus
on dust removal, thereby reducing the emissions of HM. For Hg this is less efficient
as most of the Hg emissions occur in the gaseous phase. Therefore, Hg measures are
shown separately from the measures taken to reduce Cd and Pb. Starting from Option
5 the Hg measures are included, first only for new installations in the EU(25)+, up to
a full implementation for all countries for Option 7.
While analysing table 1 its good to know that in the non-EU(25)+ countries all costs
are included. For EU(25)+ countries, where the IPPC Directive has been
implemented, this is regarded as autonomous development. Therefore the costs in the
EU(25)+ will often appear lower than for other countries because the EU(25)+
countries have to comply with EC Directives, such as the IPPC Directive, and may
already made (a part of) the costs. So, lower costs for the EU(25)+ does not imply that
they take less measures or that they have lower costs. It is just showing the
incremental costs for additional measures as a result of extra measures in a revised
HM Protocol.
Paper for the 4th meeting of the Task Force on Heavy Metals under the UNECE
Convention on Long-range Transboundary Air Pollution, Vienna 6-8 June, 2007
The costs will be presented as total annual costs (the sum of amortization and
operational costs) and are expressed in Euro (€) as of year 2000.
End-of-pipe removal of Hg is in most cases not regarded as BAT by the IPPC, and
costs are usually relatively high. Therefore, Options 6 and 7 show a relative high
increase in incremental costs.
The costs of emission reductions give, due to the limitation of cost data underlying the
results, an order of magnitude of the costs range.
Table 2 shows that overall in Europe the area at risk for Cd deposition reduces from
0.10 % for Option 1 to about nihil for Option 7. The area at risk in non-EU(25)+
diminishes from 0.16 % under Option 1 to 0,02% under Option 7. Also the
exceedance magnitudes are very low. However, it should be noted that the deposition
calculations of Cd are likely to be underestimated. Additional loads from manure
and/or fertiliser will extend the area and magnitude of exceedance in central Europe.
The risk of Pb deposition expressed as AAE is highest in the EU(25)+ (5 and 3 g/ha
yr in options 1 and 7 respectively), while the area at risk is highest in non-EU(25)+
(35% and 14% in options 1 and 7 respectively).
Finally, the risk of mercury turns out to cover a broad area in Europe. 80% of the area
is at risk under Option 1 which is reduced by 6% to 74% under option 7. The risk is
highest in non-EU(25)+ countries covering 97% of the area (with an AAE of 0,14 g
ha-1 yr-1) under option 1. Peak Average Accumulated Exceedances that are higher than
0,4 g ha-1 yr-1 occur in most of the Parties under the Convention (see Hettelingh et al.,
2006, pp. 53) Under Option 7 the risk of Hg in the non-EU(25)+ diminishes to an area
at risk of still 91% (with an AAE of 0,069 g ha-1yr-1). Areas with AAE peaks
exceeding 0,4 g ha-1yr-1 are reduced to a limited set of scattered grid cells in the whole
of Europe. The southern part of Greece remains highly exposed.
In the end it should be noted that the risk of Options 2 to 6 lie between those
described for Options 1 and 7.
Other
It is important to note that many measures that target a specific HM have substantial
co-benefits as ultimately a whole group of substances (e.g. other heavy metals,
particulate matter and/or dioxins) will be reduced. So thus, the injection of activated
carbon, as a Hg emission reduction measure has, a co-benefit due to the removal of
specific other gaseous compounds, such as dioxins. The relative decrease of emissions
by metal as a result of tightening the ELVs is shown in figure 1.
Paper for the 4th meeting of the Task Force on Heavy Metals under the UNECE
Convention on Long-range Transboundary Air Pollution, Vienna 6-8 June, 2007
100%
Percentage
90%
80%
Cd
70%
60%
Hg
50%
Cr
40%
30%
Cu
20%
10%
Ni
Pb
As
Se
0%
EU(25) plus
Norway and
Switzerland
Other European
UNECE Members
Total UNECE
Europe
Zn
Country Group
Figure 1
Emission reduction potential of a possible revision of the HM Protocol
following the tightening of the ELVs
Paper for the 4th meeting of the Task Force on Heavy Metals under the UNECE Convention on Long-range Transboundary Air Pollution, Vienna 6-8
June, 2007
Emissions, costs and area at risk for the different options in 2020
New
source
Existing
source
Hg measures
New
source
2. Additional measures Cd
and Pb new.
X
X
3. Additional measures Cd
and Pb new. The EU+ also
existing.
4. Additional measures Cd
and Pb new and existing.
X
X
X
X
X
X
X
5. Additional measures Cd
and Pb new and existing. The
EU+ also additional measures
Hg new.
6. Additional measures Cd
and Pb new and existing.
Additional measures Hg new
and the EU+ also for existing.
X
X
X
X
7. Additional measures Cd
and Pb new and existing plus
additional measures Hg new
and existing.
X
X
X
X
X
X
X
X
X
X
X
X
X
Cd
Existing
source
1. Full Implementation HM
Protocol.
X
X
X
Emissions (tonnes)
Pb
Hg
Costs (M€)
Reduction
(%)
Countries
Dust measures
Reduction
(%)
Option
Reduction
(%)
Table 1
EU(25)+
95
0%
2622
0%
141
0%
non-EU(25)+
121
0%
3139
0%
175
0%
All
217
0%
5761
0%
316
0%
EU(25)+
90
5%
2264
14%
141
0%
non-EU(25)+
103
4778
20%
17%
172
194
15%
11%
2514
All
313
2%
1%
EU(25)+
81
15%
1548
41%
141
0%
non-EU(25)+
103
15%
2514
20%
172
2%
All
184
1548
29%
41%
313
81
15%
15%
4062
EU(25)+
141
1%
0%
non-EU(25)+
68
44%
1265
60%
166
5%
0
0
0
448
2 546
2 994
1 344
2 546
3 890
1 344
7 637
8 981
4 848
All
149
31%
2813
51%
307
3%
EU(25)+
83
13%
1551
41%
124
12%
non-EU(25)+
68
44%
1265
60%
166
5%
7 637
All
151
31%
2816
51%
290
8%
EU(25)+
77
19%
1540
41%
89
non-EU(25)+
74
39%
1276
59%
All
151
30%
2816
Area at risk (%)*
Cd
Pb
Hg
0,03
38
66
0.1
33
80
<0.10
<33
<80
66
<0.10
<33
<80
66
<0.10
<33
<80
12 485
>0.02
>19
>74
37%
11 936
0.02
27
61
148
16%
10 187
51%
237
25%
22 123
>0.02
>19
>74
EU(25)+
77
19%
1540
41%
89
37%
27
61
60
50%
1250
60%
94
46%
11 936
15 454
0.02
non-EU(25)+
All
137
37%
2790
52%
183
42%
27 390
0.02
19
74
Emission and Cost data have been obtained from Visschedijk et al. (2006) (See text for an explanation on the grey marked rows ).
Area at risks data have been obtained from Hettelingh et al. (2006)
*Please be aware that the countries covered within the two studies is not exactly the same.
Due to rounding off the numbers, there migth be a small difference between the numbers in the TNO study and the numbers in the table
Paper for the 4th meeting of the Task Force on Heavy Metals under the UNECE
Convention on Long-range Transboundary Air Pollution, Vienna 6-8 June, 2007
Table 2
The area at risk (%) and Average Accumulated Exceedance (g ha-1yr-1) of areas
within the EMEP domain of Europe, in the EU25 Member States plus Norway
and Switzerland (EU(25)+), and other Parties under the Convention (nonEU(25)+) for the Options 1 and 7.
Ecosystem
areas in1:
Area at
risk
Cd
Average
Accumulated
Exceedance
Option 1
Pb
Area at
Average
risk
Accumulated
Exceedance
(g/ha yr)
EU(25)+
non-EU(25)+
All
(%)
0,03
0,16
0,1
nil
nil
nil
(g/ha yr)
(%)
30
35
33
Cd
EU(25)+
non-EU(25)+
All
0,02
0,02
0,02
nil
nil
nil
Area at
risk
25
14
19
5
2
3
Option 7
Pb
3
1
2
Hg
Average
Accumulated
Exceedance
(g/ha yr)
(%)
64
97
80
0,11
0,14
0,12
Hg
57
91
74
0,06
0,069
0,064
1
EU25+: EU countries before 31 december 2006 excl. Malta for the risk assessments of all metals and Finland for the
assessment of the risk of mercury, due to lack of data.
4. General discussion on a possible revision of the HM Protocol
In this paper seven options to reduce HM further have been investigated. Although
more options could have been undertaken they give a good overview of what can be
done to abate HM emissions further. Variants to the options in this paper are different
time frames for the implementation of measures for Western countries (the EU+ and
North America) and European non-EU countries. Other possibilities are e.g. a
difference in obligations, binding measures or non-binding measures.
The options are independent of where the further reduction land in a protocol.
One could revise the current HM Protocol or draft a new ‘Second HM Protocol’.
Another possibility is that since the HM Protocol is to a very large extent a dust
related protocol that the HM Protocol is extended to a protocol on primary particulate
matter (PM) and heavy metals (a Protocol on PM/HM). It could be a technologybased protocol with obligations on BAT and ELVs and not on mandatory emission
ceilings. This possibility might be attractive for emission inventories of HM and PM
are not as accurate as are the substances now addressed in the Gothenburg Protocol.
Such a technology-based protocol can be drafted fairly quickly. Such a protocol on
PM/HM would also have the advantage of not increasing the complexity of the
Gothenburg Protocol with PM.
The current idea is to add PM to the possibly revised Gothenburg Protocol. Since HM
and primary PM are largely overlapping one could also include HM into the revised
Gothenburg Protocol. A distinct disadvantage would be that it would become even
more difficult to implement and ratify such an all-encompassing protocol.
Paper for the 4th meeting of the Task Force on Heavy Metals under the UNECE
Convention on Long-range Transboundary Air Pollution, Vienna 6-8 June, 2007
This paper explores options to reduce HM emissions from stationary sources. For Hg
the EU has many product regulations on Hg containing products. These regulations go
beyond the measures in the HM Protocol in Annex VI (mandatory measures) and
Annex VII (voluntary measures). For a new HM protocol one could opt for the EU+
and North America to have more mandatory Hg product measures in Annex VI. Other
European non-EU countries could possibly have time exemptions on these additional
Hg measures. For Cd and Pb containing products the situation is more complex. It is
only after combustion that these metals are released into the atmosphere. One could
place measures on the limitation of Cd and Pb in products into a non-mandatory
annex (e.g. Annex VII).
5. References
Visschedijk, A.J.H., H.A.C. Denier van der Gon, M. van het Bolscher, P.Y.J. Zanveld
(2006), Study to the effectiveness of the UNECE Heavy Metals (HM) Protocol
and costs of additional measures, Phase II: estimated emission reduction and
costs of options for a possible revision of the HM Protocol, TNO-report 2006A-R0087/B.
Hettelingh, J.-P., J. Sliggers (eds.), M. van het Bolscher, B.J.Groenenberg, I. Ilyin,
G.J.Reinds, J.Slootweg, O.Travnikov, A.Visschendijk, W.de Vries (2006),
Emissions, depositions, critical loads and exceedances in Europe, Report of the
Directorate for Climate Change and Industry, Dutch ministry of VROM (also
available at the CCE from www.mnp.nl/cce).