MK. METIL KAJIAN LINGKUNGAN
PENDUGAAN
RISIKO EKOLOGIS
smno.psdl.pdkl.ppsub2013
LINGKUP & BATASAN
Pendugaan risiko ekologis adalah
pendekatan konseptual dan metode
khusus untuk menduga risiko
ekologis ytang ditimbulkan oleh
lokasi-lokasi yg tercemar .
Lokasi tercemar adalah lokasilokasi yang tercemar oleh limbah
buangan atau oleh kekeliruan
penggunaan bahan kimia atau oleh
aktivitas manusia lainnya.
Pengertian ini meliputi lahanlahan yg tercemar oleh
pembuangan limbah di
permukaan dan bawahpermukaan; air permukaan dan
sedimen yang tercemar oleh
buangan limbah cair atau
penimbunan limbah-padat; serta
lahan-lahan dan perairan yang
tercemar oleh aktivitas
transportasi darat, air/ laut dan
udara.
PENDUGAAN RISIKO EKOLOGI = Ecological risk
assessment (ERA) MERUPAKAN PROSES menghimpun,
mengorganisir, dan menganalisis informasi untuk
memperkirakan efek-efek yang tidak diinginkan terhadap
organisme (nonhuman) , populasi atau ecosystems.
Metode ini dikembangkan pada tahun 1980-an untuk
memberikan landasan bagi pengambilan keputusan
lingkungan, metode ini setara dengan metode “human health
risk assessment”.
Metode pendugaan ini dikembangkan berdasarkan
pengalaman dalam menerapkan metode-metode :
Human health risk assessment,
Environmental hazard assessment, dan
Environmental impact assessment .
All varieties of risk assessment are based on the
recognition that decisions must be made under
conditions of uncertainty and that the
desirability of alternative outcomes depends on
their likelihood as well as their utility.
4
Tujuan utama dari pendugaan
risiko ekologis di lokasi-lokasi
yang tercemar adalah untuk
menyediakan informasi yang
diperlukan bagi pengambilan
keputusan tentang rehabilitasi /
pemulihan kembali lokasi
tercemar tersebut.
Ada dua tujuan lain dari pendugaan risiko
ekologis, selain yang terkait dengan
pengambilan keputusan rehabilitasinya, yaitu:
Pertama adalah PENGUNGKAPAN MISTERI
Publik ingin mengetahui apa saja dampak yang
mungkin ditimbulkan oleh pencemaran
lingkungan dan manfaat apa yang dapat
diperoleh dari rehabilitasinya.
Ke dua adalah pendugaan KERUSAKAN .
“Siapa yang menimbulkan pencemaran suatu
lokasi berkewajiban memberikan kompensasi
atas kerusakan lingkungan yg tidak dapat diremediasi” atau “di-rehabilitasi” .
Paling tidak ada tiga sarana untuk menyatakan
risiko ekologis yg lazim digunakan untuk
mendukung keputusan-keputusan remediasi /
rehabilitasi.
6
1. Menentukan apakah baku-mutu risiko telah
terlampauai
Baku mutu risiko ini biasanya dituangkan dalam bentuk
peraturan perundangan, mulai dari pusat hingga daerahdaerah, termasuk konvensi yang tidak etertulis.
Baku mutu ini ditetapkan “berbasis risiko” dalam arti
bahwa mereka ditetapkan sesuai dengan konsentrasi
bahan pencemar yang diperkirakan akan menimbulkan
dampak minimal terhadap komunitas akuatik di perairan
atau lingkungan lain.
7
2. KELEMAHAN
BAKU-MUTU BERBASIS RISIKO
Kelemahannya, baru tersedia baku-mutu untuk
beberapa jenis bahan kimia, tidak berlaku untuk
media lain (selain air) , tidak berkaitan dengan efekefek khusus, dan hanya mempunyai sedikit sekali dara
p[rediktif pada lokasi-lokasi tertentu.
Baku mutu untuk air dan media lainnya telah
dikembangkan di beberapa negara, seperti Canada,
Europe, dan USA.
Mengingat penggunaan baku mutu ini relatif cepat,
mudah, dan mudah pengamanannya, maka metode ini
cepat menjadi populer.
Akan tetapi karena kriteria yang tersedia masih
terbatas, maka tidak dapat digunakan untuk
pendugaan reseptor dan pencemar secara generik.
8
Estimate the likelihood of exceeding some risk level
that is a threshold for regulatory significance
For example, the parties to a remedial decision may
agree that remediation is called for if the abundance
of fish in a stream contaminated by leachate is
reduced by at least 20%.
This type of expression of assessment results has been
called for by the EPA Office of Solid Waste and
Emergency Response (OSWER) (Quality Assurance
Management Staff, 1994).
The ease of generating this assessment result
depends on the magnitude of site effects relative to
the threshold.
For example, if the fish abundance in the
contaminated stream is less than 0.1/m of stream
reach and all reference streams have at least 5/m,
the level of effect clearly exceeds the 20% threshold.
9
3. Estimasi Risiko
Yaitu estimasi distribusi peluang dari dampak
atau tingkat-dampak dengan peluang kejadian
tertentu.
For example, one might estimate that the most
likely (50th percentile) effect is a 10% reduction
in fish abundance, but the worst case estimate
(90th percentile) is that fish abundance is
reduced by as much as 60% relative to an
uncontaminated state.
This is clearly the most difficult form of output
to generate with any confidence.
Kalau risiko remediasi harus diseimbangkan
dnegan risiko pencemar, atau kalau semua
kerusakan akibat pencemaran dikumpulkan,
maka tingkat dampak dapat diperkirakan.
10
Tujuan utama dari smeua analisis ini adalah
untuk mendukung tindakan-tidakan
remediasi.
Alternatif REMEDIASI meliputi:
1. Pengambilan limbah atau media yang
tercemar untuk dibuang atau diolah ,
2. Pengolahan limbah di tempat dengan
menerapkan perlakuan-kimiawi
3. Memacu degradasi biologis, isolation atau
redirection (e.g., grout curtains),
4. Immobilization di tempat (e.g., grout
injection),
5. Kontrol Land-use
6. Paparan Ekologis, penutupan lokasi
tercemar dengan suatu penutup tertentu
7. No action (remediasi melalui proses-proses
degradasi alamiah atau pengenceran
alamiah).
11
Untuk dapat mendukung keputusan remediasi, pendugaan
risiko harus menyediakan informasi mengenai media apa
atau limbah apa saja yang memerlukan remediasi , serta
kriteria apa (mis., konsentrasi yg hareus dicapai atau luas
daerah yang harus ditutup) yg akan dapat mengurangi
risiko hingga tingkat yang telah ditetapkan.
KERANGKA ANALISIS
ECO-RISK
Semua pedoman dan aturan tentang remediasi lokasi tercemar
yang berlaku menurut peraturan-perundnagan digunakan
sebagai sarana untuk menentukan dampak lingkungan apa saja
yang perlu di-remediasi.
One of the defining features of ecological risk assessment is
the standard framework which has evolved from the National
Research Council framework for human health risk
assessment (National Research Council, 1983)
Kerangka analisis lazimnya terdiri atas:
Tahapan perumusan masalah,
Tahapan analisis , dan
Tahapan karakterisasi Risiko.
Apa saja komponen dari Kerangka Analisis ini, sangat
beragam.
Akan tetapi pedoman umum adalah berikut ini.
13
Kerangka Analisis Pendugaan Risiko Ekologis
(EPA, 1998).
Perencanaan:
Penduga Risiko/
Manajer Risiko/
Stakeholder
Mengkomunikasikan hasil-hasil analisis
kepada Manager Risiko
Manajemen Risiko dan mengkomunikasikan hasilhasilnya kepada pihak-pihak yg berkepentingan
14
Perumusan masalah :
Merupakan fase p[erencanaan dan
pembatasan masalah
Tahapan ini meliputi:
1. Mengintegrasikan semua informasi yang tersedia —
Merangkum semua informasi tentang sumber-sumber,
bahan pencemar, pengaruh & dampak, dan lingkungan
reseptor dampak.
2. Pendugaan Kondisi-Akhir — Mendefinisikan secara
operasional nilai-nilai lingkungan yang harus
dilindungi.
3. Penyusunan Model Konseptual — Menyusun deskripsi
tentang hubungan hipotetik antara limbah dengan
reseptor akhir .
4. Rencana Analysis — Menyusun suatu rencana untuk
memperoleh data yang diperluakn dan melakukan
pendugaan risiko.
Analysis merupakan tahapan dimana dilakukan
evaluasi teknis data tentang paparan dan
dampaknya
15
KARAKTERISASI
KOMPONEN PAPARAN
1. Ukuran Paparan — Results of
measurements indicating the nature,
distribution, and amount of the waste
and its components at points of
potential contact with receptors
2. Analisis Paparan — A process of
estimating the spatial and temporal
distribution of exposure to the
contaminants
3. Profil Paparan — A summary of the
results of the exposure analysis
KARAKTERISASI
KOMPONEN DAMPAK
1. Ukuran Dampak — Results of
measurements or observations
indicating the responses of
assessment endpoints to variation in
exposure
2. Analisis respon ekologis — A
quantitative analysis of the effects
data
3.
Profil Stressor–respon — The
component of the ecological
response analysis that specifically
deals with defining a relationship
between the magnitude and
duration of exposure and relevant
effects
KARAKTERISASI RISIKO merupakan fase dimana hasilhasil dari fase analisis diintegrasikan untuk
memperkirakan dan mendeskripsikan risiko-risiko.
Tahapan ini terdiri atas:
1. Estimasi Risiko — The process of using the results of
the analysis of exposure to paramaterize and implement
the exposure–response model and estimate risks and of
analyzing the associated uncertainty
2. Deskripsi Risiko — The process of describing and
interpreting the results of the risk estimation for
communication to the risk manager
MANAJEMEN RISIKO merupakan proses s, in this
context, the process of making a decision concerning
the need for remediation.
Proses ini dilakukan pada dua titik dalam kerangka
analisis.
1.
Pada awal pendugaan, the risk manager provides
policy input to the problem formulation.
2. Pada akhir pendugaan, the risk manager learns the
results of the risk analysis and makes a decision.
Manajemen risiko
adalah proses pengukuran atau penilaian risiko serta
pengembangan strategi pengelolaannya.
Strategi yang dapat diambil antara lain adalah
memindahkan risiko kepada pihak lain, menghindari
risiko, mengurangi efek negatif risiko, dan
menampung sebagian atau semua konsekuensi risiko
tertentu.
Manajemen risiko tradisional terfokus pada risikorisiko yang timbul oleh penyebab fisik atau legal
(seperti bencana alam atau kebakaran, kematian,
serta tuntutan hukum).
19
PROSES REMEDIASI
Pendugaan risiko ekologis merupakan suatu
komponen dari prose remediasi yang
meliputi beragam kegiatan perencanaan,
sampling, analysis, remediation, dan aktivitas
rekayasa, semuanya ditujukan untuk
mengubah lokasi menjadi kondisi yang
normal.
Asesor Risiko Ekologis harus terlibat dalam
semua tahapan proses remediasi.
BIOREMEDIATION TECHNOLOGIES IN SOIL.
1. Criteria for bioremediation
2. Land farming
3. Phytoremediation
4. Bioventing
20
Diagram alir proses pemulihan kembali lokasi yang
tercemar
Karakterisasi lokasi
dan Pelingkupan
Perumusan
Masalah
Rencana
Analisis
Sampling &
Analisis
Baseline
Pendugaan Risiko
EKologis
Rencana
Kegiatan &
Minat Publik
Tindakan2
Penyembuhan/
Pemulihan
Pendugaan
Kerusakan
Pendugaan
Alternatif
Penyembuhan
Keputusankeputusan
Pemantauan
Pasca
Pendugaan
Efikasi
21
This diagram does not include
identification of candidate sites or the
document review and revision processes,
which typically occur after the
production of each plan or assessment
document.
Although it is valuable in theory to
assure that the assessors are not going
off on a wrong course, it is the authors’
experience that risk managers and the
staffs of regulatory agencies are
overcommitted and often perform few or
superficial reviews of intermediate
products.
Proses remediasi yang bersifat general
ini tidak dapat digunakan untuk
menangani bencana (emergency
responses).
If a site is contaminated by a spill of a
hazardous material, spending a period
of months planning, seeking regulator
review comments, gathering ecological
data, etc. while the contaminant spreads
from the spill site would be
inappropriate.
Rather, existing emergency response
plans should be implemented to contain
and remove the material quickly.
If there is residual contamination
following the emergency response, this
process may be used to assess and
remediate it.
KARAKTERISASI LOKASI &
PELINGKUPAN
Before an ecological risk assessment can
be performed, it is necessary to have a
basic understanding of the nature and
extent of contamination, potential routes
of exposure, and ecological resources
present at the site.
Tinjauan lapangan ke lokasi dan survei
pendahuluan (pengenalan) harus
dilakukan , dan harus dapat dihimpun
informasi tentang kondisi lokasi dan
sejarah keberadaan dan dinamika lokasi
tersebut.
Pengenalan lokasi meliputi kunnjungan lokasi dan
mendeskripsikan karakteristik fisik lokasi
(topography, geology, hydrology, anthropogenic
structures, and other features that would affect
transport and fate);
Sumber potensial pencemar, seperti drums, lagoons,
dan pipes;
Tipe-tipe komunitas ekologis , ukuran besarannya,
dan kondisi aktual yang sedang berlangsung.
In addition to the field reconnaissance, local
experts should be consulted, local residents and
employees should be interviewed, and
information should be collected from existing
sources such as aerial photographs, maps such
as wetland inventories and endangered species
range maps, and prior assessments of the site or
nearby sites.
Previous remedial actions taken at the site that
have affected the environment, such as capping
of landfills, should also be described.
If data concerning the composition and
concentration of the contaminants in site media
are unavailable from existing information,
reconnaissance sampling and analysis may be
performed.
Sampling harus difokuskan pada sampel untuk
analisis spektrum luas atau sampel lokasi yang
paling menderita parah.
Alternatively, portable devices such as
photoionization detectors (PIDs) may be used
to provide rapid, broad-spectrum analytical
data.
Data yang dihimpun selama studi
pendahuluan pengenalan lokasi harus
digunakan untuk melakukan pelingkupan
dalam mempersiapkan rencana proses
pendugaan secara keseluruhan
Informasi yang tersedia dapat dipakai untuk
menentukan apakah ada bahaya potensial
yang mengancam.
If there is sufficient information concerning
the concentrations of contaminants on the
site, a screening assessment may be
performed, instead of the scoping
assessment, to identify the hazard and
narrow the scope of the assessment.
PROSES PERUMUSAN
MASALAH
The problem formulation defines the
purpose, scope, and goals of the
assessment, as well as the methods by
which it will be performed.
Its products include the assessment
endpoints, the conceptual model, and
the analysis plan.
Perumusan masalah harus dilakukan
secara kolaboratif
The ultimate arbiter of the scope, methods, and
content of the assessment is the decision maker who is
responsible for the remedial decision.
The other necessary participants in the problem
formulation are the technical experts who will prepare
the analysis plan and carry out the assessment.
Potential additional participants include
representatives of the responsible parties, resource
agencies, and local citizens.
Typically, a screening assessment is performed to
determine the nature and scope of the assessment
problem
DERAJAT PENTINGNYA DAMPAK
Kriteria Dampak Penting (PP No 27 1999, Pasal 5 ayat 1):
1.
2.
3.
4.
5.
6.
Jumlah manusia yg terkena dampak
Luas wilayah persebraan dampak
Intensitas dan lamanya dampak berlangsung
Banyaknya komponen lingkungan lain yg terkena
dampak
Sifat komulatif dampak
Berbalik (reversible) atau tidak berbaliknya (irreversible)
dampak
Rentang sekala yang digunakan:
1 = kurang penting
2 = Cukup penting
3 = Penting
4 = Lebih penting
5 = Sangat Penting
29
RENCANA ANALISIS
The analysis plan (RI work plan) explains how the
decisions made during the problem formulation process
will be implemented.
A screening ecological risk assessment is typically
included in the analysis plan to provide a technical justification for the scope of ecological sampling, analysis, and
assessment activities.
The analysis plan is a plan for obtaining the data needed
for the baseline assessment, as identified in the problem
formulation process, and a plan for using those data to
assess ecological risks.
KARAKTERISASI RISIKO
is the phase in which the results of the analysis phase are
integrated to estimate and describe risks. It consists of:
1. Estimasi risiko: The process of using the results of the
analysis of exposure to paramaterize and implement the
exposure–response model and estimate risks and of analyzing
the associated uncertainty
2. Deskripsi Risiko: The process of describing and interpreting
the results of the risk estimation for communication to the risk
manager
30
ITERASI DALAM PENDUGAAN RISIKO
The ecological risk assessor must ensure that the
proposed activities will in fact fill the needs of the
assessment by consulting with the authors of the
sampling and analysis sections and by authoring a plan
for performing the baseline ecological risk assessment
using that data set.
If the site is poorly characterized by existing data, the
assessment may be carried out in phases.
That is, a Phase 1 sampling and analysis program may
be defined and carried out, which provides the basis for
planning a more-focused second phase.
This sequence requires that the results of the Phase 1
studies be used to conduct a screening assessment, which
is used to identify any data gaps that must be filled in
Phase 2.
Berapapun iterasi yang diperlukan, dapat
dilakukan dalam tahapan planning, sampling
dan analysis, serta tahapan pendugaan risiko .
However, few schedules or budgets permit more than
two phases, and few sites are so complex as to require
them.
31
BASELINE
ECOLOGICAL RISK ASSESSMENT
In contrast to the screening assessment, which defines
the scope of the baseline assessment, the baseline
assessment uses new and existing data to evaluate
the risk of leaving the site unremediated.
Tujuan kegiatan baseline ini adalah untuk menentukan :
(1) if significant ecological effects are occurring at the
site,
(2) the causes of these effects,
(3) the source of the causal agents, and
(4) the potential future risks from leaving the system
unremediated.
32
Analisis baseline ini menyediakan informasi
ekologis untuk menentukan perlunya remediasi.
The baseline risk assessment is part of the
remedial investigation.
Because the baseline assessment focuses on a
smaller number of chemicals and receptors than
the screening assessment, it can provide a higher
level of characterization of toxicity to the
populations and communities at the site.
In the baseline ecological risk assessment, a
weight-of-evidence approach should be employed
to determine if and to what degree ecological
effects are occurring or may occur.
33
Most baseline ecological risk
assessments focus primarily on
current risks.
Pendugaan risiko di masa mendatang
diperlukan kalau:
1. Paparan bahan pencemar
diperkirakan semkain meningkat di
masa mendtaang (e.g., a
contaminated ground water plume will
intersect a stream)
2. Suksesi biologis diperkirakan dapat
meningkatkan risiko (e.g., a forest
will replace a lawn)
3. Natural processes will result in
significant recovery in the near term
without remedial actions (i.e., the
expense and ecological damage
associated with remedial actions may
not be justified)
ALTERNATIF
REMEDIASI
If significant risks to humans or ecological receptors
are found by the baseline risk assessments, it is
necessary to assess the remedial alternatives. This
is referred to as the feasibility study.
For the no-action alternative and for those
alternatives that simply limit human access to and
use of the site, the risks are those identified in the
baseline ecological risk assessment.
Other remedial alternatives actively reduce site
contamination but also cause physical disturbances,
which have their own ecological risks.
These remedial risks include destruction of the biotic
communities on the site and on uncontaminated
sites for borrow pits, landfills, roads, laydown areas,
parking lots, etc.
35
The remedial ecological risk assessment must consider
these direct effects, secondary effects such as erosion and
habitat
fragmentation, and the expected rate and degree of
recovery of the disturbed areas given the site management
and expected land uses.
The importance of assessing remedial risks is demonstrated
by the record of decision (ROD), in which contaminant
levels that are estimated to constitute a significant risk to
shrews and wrens, but not humans, were left in place
because the potential remedial actions would result in
destruction of riparian forests and wetlands.
That is, the remedial risks exceeded the baseline risks.
The results of this assessment are used to develop a
proposed plan for remediation.
That plan is presented to the public for review and
comment.
The results of this process are used to revise the plan,
which is then incorporated into the ROD.
36
PENDUGAAN EFIKASI
Pendugaan Risiko EKologis yang dilakukan
setelah selesainya kegiatan remediasi biasanya
untuk memenuhi persyaratan legal atau untuk
tujuan kelestarian lingkungan .
Kalau kegiatan remediasi maninggalkan
sisa/residu pencemar di tempat, dan bukannya
menghilangkannya atau mendegradasikannya ,
pihak yang berwenang diharuskan memantau
lokasi remediasi dan setiap lima tahun
melakukan pendugaan efikasi kegiatan
remediasi ditinjau dari proteksi kesehatan
manusia dan lingkungan, hingga dimungkinkan
penggunaan lokasi yang telah diremediasi
secara aman.
37
The nature of this monitoring and
assessment activity is specified in
the ROD.
However, the monitoring required
is usually minimal and focused on
human health risks.
Therefore, the site owner must, to
meet planning and sitestewardship needs, determine
whether additional monitoring is
needed to ensure that risks to
environmental resources have
been sufficiently reduced.
Both the legal requirement and the environmental
stewardship goals require the collection of data to
characterize the post-remedial condition and to estimate
levels of effects.
All of the techniques that were applied to earlier stages
of the assessment could be employed at this stage.
However, efficacy assessments are typically based on a
minimal monitoring program that is focused on one or a
few critical issues.
The data analyses are also typically minimal and are
focused on clearly defined criteria for acceptable risk.
39
Alternatif Hasil-hasil dari Proses Pendugaan
EFIKASI :
(1) RISIKO MINIMUM, proses pendugaan
dan remediasi dapat berakhir;
(2) RISIKO SIGNIFIKAN, diperlukan
remediasi lebih lanjut;
(3) RISIKO TIDAK MINIMAL, tetapi tidak
memerlukan remediasi tambahan,
sehingga lanjutkan pemantauan .
40
PENDUGAAN KERUSAKAN
The Natural Resource Damage Assessment (NRDA)
provisions of CERCLA require that the residual injuries,
following remediation, be assessed so that natural resource
trustees can be compensated for lost natural resource
services.
The purpose is to use the funds to restore the environment to
provide the lost natural resource services. To be efficient
and to ensure that remedial actions are taken which avoid
excessive payments of natural resource damages, NRDA
should be integrated with the rest of the CERCLA process.
Therefore, results of the baseline and remedial alternatives
risk assessments are important input to the NRDA, and
selection of assessment endpoints which are also “natural
resource services” could save assessment costs and damage
payments. While this integration is logical and would be
cost-effective, it is complicated by the fact that, except for
informing the natural resource trustees, the EPA does not
participate in NRDA activities.
Therefore, NRDA is not explicitly addressed in the EPA
Data Quality Objectives (DQO) process or in RI/FS-related
documents that are reviewed by the EPA.
41
PELINGKUPAN, PENAPISAN DAN
PENDUGAAN DEFINITIF
In general, ecological risk assessments are performed in
phases or tiers, including scoping assessments, screening
assessments, and definitive baseline assessments. The
successive tiers each require more time and effort. Scoping
assessments determine whether an ecological risk
assessment is needed; screening assessments determine what
contaminants, media, and receptors need to be assessed; and
definitive assessments determine the nature and magnitude
of risks. Each tier of risk assessment should include all three
phases: problem formulation, analysis, and risk
characterization. Even the most hurriedly performed scoping
assessment should define the nature of the problem, analyze
available information on exposure and effects, and explain
how they are potentially related.
The purpose of tiers of assessment is to perform the
assessment as efficiently as possible by performing only the
number of assessment activities needed to reach an informed
decision. At any point the assessment process might end
because the risks are clearly unacceptable or are clearly
negligible. Scoping assessments determine whether a formal
ecological risk assessment is needed by ascertaining whether
there is a potential for current or future exposure of
ecological receptors.
42
There are several questions to be answered.
(1) Is there a source of contaminants? The apparent waste
may be innocuous, there may actually be no waste, or
the waste may have been removed by prior actions. At
one Oak Ridge unit, the waste was merely construction
rubble.
(2) Are there currently or might there be in the future
ecological receptors on the contaminated site? In some
cases, there is no complete pathway from the
contaminants to an ecological receptor, because the
contamination is limited to an industrial facility or an
inactive industrial site that will be returned to industrial
use or converted to commercial use (i.e., a brownfield).
In those cases the site has little ecological value and is
not expected to have significant ecological value under
future land uses. There is no complete pathway on the
site because there are no significant receptors.
(3) Could movement of the contaminants result in
significant exposure of ecological receptors off the
site? The principal concern is with contamination of
surface waters and wetlands through runoff or lateral
groundwater movement. Groundwater contamination is
not normally a basis for performing an ecological risk
assessment unless the groundwater intersects the
surface or the near-surface root zone.
43
Screening assessments go beyond scoping assessments by
asking whether the identified pathways from the
contaminants to ecological receptors could result in
toxicologically significant exposures.
Screening allows assessors to focus resources by first
applying rapid and conservative assessment techniques to
screen out sites, portions of sites, media, or chemicals that
clearly pose minimal risks.
More time and effort can then be devoted to definitive
assessments that provide risk estimates by applying more
realistic and site-specific analyses to those hazards that
have not been screened out.
Chemicals that are retained by the screening process are
termed chemicals of potential ecological concern
(COPECs). Screening assessments should be conservative
and as broad as is reasonably possible so that no potential
hazards are overlooked.
44
The screening phase may itself be performed in tiers.
For example, a screening assessment may be
performed using a relatively small set of preliminary
data for the purpose of determining what sampling
and analysis needs to be performed.
The new data should then be used in a screening
assessment to determine which hazards should be
modeled and analyzed in detail in the definitive
assessment. In general, data gaps identified in
screening assessments should be treated as a basis for
including a hazard in the definitive assessment.
Receptors that may occur on the site but are
unconfirmed and routes of exposure that
are credible but have not been investigated
should be retained. Treating unknowns in
this manner results in a more credible
assessment.
If screening assessments have identified credible
hazards to ecological receptors, a definitive
assessment must estimate risks and identify
preliminary remedial goals.
45
PENDUGAAN DEFINITIF
Definitive assessments should replace
conservative assumptions with best
estimates of exposures and effects and
associated uncertainties.
Because previous tiers of assessment will
have reduced the scope of the definitive
assessment by identifying contaminants,
media, and receptors that constitute
credible hazards, it should be possible to
devote sufficient time and resources to
their assessment.
In general, additional testing and analysis
reduce uncertainties and increase realism,
thereby reducing the need to
overremediate to ensure protection.
Definitive assessments are not normally
performed in tiers unless the assessment process
reveals potentially significant pathways and
receptors that were missed by the screening
assessments.
46
The phased assessments performed at contaminated sites
require a different logical approach from the tiered
assessment schemes developed to assess risks from new
chemicals.
The latter schemes are based on the performance of brief and
inexpensive tests and simple exposure models in the first tier
and performance of more expensive and realistic tests in
higher tiers if assessments based on lower tiers are
inconclusive.
However, the acute lethality tests used in the early tiers of
those assessment schemes cannot be used to determine
acceptability of risks at a contaminated site. For example, if a
soil from a contaminated site is acutely lethal to plants, one
can conclude that there are potentially significant risks.
However, if the soil is not acutely lethal, one cannot conclude
that there are no potentially significant risks.
The soil may in fact be lethal in longer exposures or may
reduce growth or seed production. In hazard assessment
schemes, the insensitivity of traditional early tier tests is
compensated for by applying safety factors to the test
endpoints (e.g., median lethal concentration, LC50s) and by
using conservative assumptions in the transport and fate
models. However, when testing contaminated media, those
techniques are not applicable.
Therefore, one must begin with a sensitive test in order to
avoid falsely concluding that there are no significant risks.
47
Tiered assessment schemes for ecological risk
assessment are more complex than those for
human health risk assessment because of the
multiple lines of evidence that are available to
ecological assessors.
Risk Based Corrective Action (RBCA) scheme
prescribes that the assessment is performed by
comparing modeled or measured exposure levels
for individual chemicals in air, soil, and
groundwater to defined levels that constitute
thresholds for significant human risk.
In RBCA, three tiers of exposure values are defined
by use of (1) generic values, (2) easily derived
sitespecific values, and (3) values derived by
complex and extensive site-specific analyses.
Ecological risk assessors perform similar analyses
but also employ toxicity tests of contaminated
media from the site and surveys of biota at the site.
Surveys range from analyses of body burdens and
biomarkers to surveys of species composition and
abundance. Any of these lines of evidence may be
employed in any tier of the assessment, depending
on the availability of data, the availability of time
and resources to obtain data, or the
appropriateness to the source and receiving
environment.
48
PENDUGAAN RISIKO KESEHATAN
MANUSIA
Risiko ekologis dan risiko kesehatan
manusia dianggap sama pentingnya,
sehingga pendugaannya dapat dilakukan
secara bersinergis.
Some information and data are likely to
be relevant for assessing both human and
environmental threats.
Common data needs identified during
problem formulation should be met in
such a way as to avoid duplication of
effort.
Hal yang sangat penting ialah adanya
koordinasi yang efektif antara asesor
risiko ekologis dengan asesor risiko
kesehtaan manusia, sehingga smeua dtaa
dna informasi dapat saling diakses dan
dimanfaatkan secara optimal.
DATA & INFORMASI
YANG DIPERLUKAN
Common data needs for human and
ecological risk assessments are
determined by the individual
characteristics of the site and by the
scale of the assessments.
In general, the following data are likely
to be useful for both human health and
ecological risk assessments.
Differences between ecological and
human health effects data needs are
noted in parentheses.
Konsentrasi pencemar kimia dalam suatu
media meliputi :
– Soils/sediments (concentrations in the pore water are
useful in ecological risk assessments)
– Surface water (concentrations of dissolved forms of
chemicals are useful for ecological risk assessments)
– Groundwater (not usually needed for ecological risk
assessment)
– Air (not usually needed for health or ecological risk
assessments of waste sites)
– Biota, including those consumed by humans, such as
fish, geese, deer (whole body concentrations will be
needed for ERAs, not just “edible parts”), plus food
for ecological endpoint species such as mice for hawks
and foxes and earthworms for thrushes and shrews
• Chemical inventories (including chemicals known
or thought to have been deposited on the site)
• Operational history and current practices at the site
• Factors affecting fate and transport of chemicals;
for example:
– Physical parameters — geohydrologic setting, soil
properties, topography
– Bioaccumulation models, particularly for
exposure pathways involving indirect exposures
to humans via the food chain
• Background concentrations of chemicals
PERBEDAAN
PENDUGAAN RISIKO EKOLOGIS
DAN
RISIKO KESEHATAN MANUSIA
Ecological risk assessments are more complex
than human health risk assessments and are
fundamentally different in their inferential
approaches.
The greater complexity is mainly due to the large
number of species and the diversity of routes of
exposure that must be considered in ecological
risk assessments.
However, the differences in inferential approach
and part of the greater complexity are due to the
fact that ecological risk assessments for waste
sites may be based on epidemiological
approaches while human health risk assessments
for the waste sites are nearly always based on
modeling.
This discrepancy raises the question, why not just
model ecological risks as well?
Alasannya berikut ini.
53
Epidemiological approaches, when they are
feasible, are fundamentally more reliable than
modeling, because they address real observed
responses of real receptors. Human health risk
assessments are based on epidemiology when
possible, but epidemiology is (fortunately) not
feasible for most sites because there are no
observable effects in human populations.
Ecological epidemiology is feasible in
practice, because nonhuman organisms reside
on most sites and are, in some cases,
experiencing observable exposures and
effects.
Ecological epidemiology is feasible in
principle, because the levels of effects that are
deemed to be significant by most regulatory
agencies are observable in many populations
and communities.
54
Because of the assumptions that must be made to
model risks, the uncertainties in model-generated
risk estimates are large.
These uncertainties can be accepted in practice by
human health assessors because the effects are
not observable.
However, it is common for modeled ecological
risks to be manifestly incorrect because the
predicted effects are not occurring or effects are
observed where they are not predicted.
Therefore, it is incumbent to use an
epidemiological approach to avoid mistakes and
embarrassment.
MENGAPA SATUAN-SATUAN EKOLOGIS
LEBIH SENSITIF DIBANDING MANUSIA
Secara umum telah dipahami dan diyakini
bahwa remediasi lokasi tercemar yang
berdampak pada perlindungan kesehatan
manusia, ternyata juga dapat melindungi
organisme lain.
For this reason, when ecological risks, but not human
risks, are estimated to be significant, the apparent
discrepancy should be explained.
Despite the highly protective endpoints in human health
risk assessments and the use of large safety factors that
exaggerate risks, the risks to nonhuman organisms are
often so much greater that, for a variety of reasons,
ecological risks are estimated to be greater.
Kalau risiko ekologisnya lebih besar, hal ini harus dapat
dijelaskan se-jelas mungkin.
Tipe-tipe penjelasan yang dapat dilakukan meliputi:
• Ecological receptors experience modes of exposure, such
as respiration of water, consumption of sediment, or
drinking from waste sumps, that do not occur in humans.
• Ecological receptors experience quantitatively greater
exposure such as a diet of 100% local fish.
• Ecological receptors include particular taxa with
inherently greater sensitivity than humans.
• Secondary effects such as reduced production of
herbivore populations due to loss of plant production are
not important for humans.
1.
2.
3.
4.
5.
6.
7.
8.
Pengubahan bentuk lahan dan atau bentang alam
Eksploitasi sumberdaya alam, baik yg terbarui maupun
yg tidak terbarui
Proses dan kegiatan yg secara potensial dpt
menimbulkan pemborosan, kerusakan dan kemerosotan
pemanfaatan sumberdaya alam
Proses dan kegiatan yg hasilnya dpt mempengaruhi
lingkungan sosial dan budaya
Proses dan kegiatan yg hasilnya dpt mempengaruhi
pelestarian kawasan konservasi SDA dan atau
perlindungan cagar budaya
Introduksi jenis tumbuhan, hewan dan jasad renik
Pembuatan dan penggunaan bahan hayati dan nonhayati
Penerapan teknologi yg diperkirakan
mempunyai
potensi besar untuk mempengaruhi lingkungan
57
RISIKO EKOLOGIS & KESEHATAN
MANUSIA
The issue of scale is treated differently in human health and
ecological risk assessment.
Because human health risks are estimated for hypothetical
individuals, they can be calculated for the points in space at
which samples are collected.
For example, risks from contaminants in the water of White
Oak Creek on the Oak Ridge Reservation are calculated at
an integration point, the weir of the dam; ……
….…. where an individual is assumed to collect his or her 2
liters of drinking water every day for 30 years.
DAMPAK PENTING suatu kegiatan thd lingkungan
ditentukan oleh:
1. Jumlah manusia yg akan terkena dampak
2. Luas wilayah persebaran dampak
3. Lamanya dampak berlangsung
4. Intensitas dampak
5. Banyaknya komponen lingkungan lainnya yg akan
terkena dampak
6. Sifat kumulatif dampak
7. Berbalik (reversible) atau tidak berbaliknya dampak
58
PARTISIPAN DALAM PENDUGAAN
RISIKO EKOLOGIS
The generic framework for ecological risk assessment
identifies two participants in the process:
risk assessor and risk manager.
In the simplest case, a site owner may wish, in the absence
of regulatory requirements, to assess and potentially
remediate a site for purposes of site stewardship.
In that case the owner is the risk manager, and the technical
staff or consultants are the risk assessors.
However, the risk assessor/risk manager dichotomy is often
more complicated at contaminated sites.