pendugaan risiko ekologis
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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 . - PowerPoint PPT PresentationTRANSCRIPT
PENDUGAANRISIKO EKOLOGIS
MK. METIL KAJIAN LINGKUNGAN
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 lokasi-lokasi yang tercemar oleh limbah
buangan atau oleh kekeliruan penggunaan bahan kimia atau oleh
aktivitas manusia lainnya.
Pengertian ini meliputi lahan-lahan yg tercemar oleh pembuangan limbah di permukaan dan bawah-
permukaan; 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.
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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.
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.
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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 di-
remediasi” atau “di-rehabilitasi” .
Paling tidak ada tiga sarana untuk menyatakan risiko ekologis yg lazim digunakan untuk
mendukung keputusan-keputusan remediasi / rehabilitasi.
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1. Menentukan apakah baku-mutu risiko telah terlampauai
Baku mutu risiko ini biasanya dituangkan dalam bentuk peraturan perundangan, mulai dari pusat hingga daerah-
daerah, 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.
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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 efek-efek 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.
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Estimate the likelihood of exceeding some risk level that is a threshold for regulatory significance
For example, the parties to a remedial decision mayagree 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.
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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.
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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).
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.
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KERANGKA ANALISISECO-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.
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Kerangka Analisis Pendugaan Risiko Ekologis (EPA, 1998).
Mengkomunikasikan hasil-hasil analisis kepada Manager Risiko
Manajemen Risiko dan mengkomunikasikan hasil-hasilnya kepada pihak-pihak yg berkepentingan
Perencanaan:Penduga Risiko/Manajer Risiko/
Stakeholder
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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
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 hasil-hasil 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
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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 risiko-risiko yang timbul oleh penyebab fisik atau legal
(seperti bencana alam atau kebakaran, kematian, serta tuntutan hukum).
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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 bioremediation2. Land farming
3. Phytoremediation4. Bioventing
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Diagram alir proses pemulihan kembali lokasi yang tercemar
Karakterisasi lokasi dan Pelingkupan
Perumusan Masalah
Rencana Analisis
Sampling & Analisis
Baseline Pendugaan Risiko
EKologis
Pendugaan Alternatif
Penyembuhan
Pendugaan Efikasi
Pendugaan Kerusakan
Tindakan2Penyembuhan/
Pemulihan Pemantauan Pasca
Keputusan-keputusan
Rencana Kegiatan &
Minat Publik
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 keseluruhanInformasi 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
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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. Jumlah manusia yg terkena dampak2. Luas wilayah persebraan dampak3. Intensitas dan lamanya dampak berlangsung4. Banyaknya komponen lingkungan lain yg terkena
dampak5. Sifat komulatif dampak6. Berbalik (reversible) atau tidak berbaliknya (irreversible)
dampak
Rentang sekala yang digunakan:1 = kurang penting 2 = Cukup penting3 = Penting 4 = Lebih penting5 = Sangat Penting
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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 justifi- cation 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 areintegrated 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
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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.
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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.
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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.
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)
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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.
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The remedial ecological risk assessment must consider these direct effects, secondary effects such as erosion and
habitatfragmentation, 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.
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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.
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
site-stewardship needs, determine whether additional
monitoring is needed to ensure that risks to
environmental resources have been sufficiently reduced.
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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.
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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 .
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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.
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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.
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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.
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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.
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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.
If screening assessments have identified credible hazards to ecological receptors, a definitive assessment must estimate risks and identify
preliminary remedial goals.
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.
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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.
PENDUGAAN DEFINITIF
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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.
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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.
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
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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.
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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.
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.
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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. Pengubahan bentuk lahan dan atau bentang alam2. Eksploitasi sumberdaya alam, baik yg terbarui maupun
yg tidak terbarui3. Proses dan kegiatan yg secara potensial dpt
menimbulkan pemborosan, kerusakan dan kemerosotan pemanfaatan sumberdaya alam
4. Proses dan kegiatan yg hasilnya dpt mempengaruhi lingkungan sosial dan budaya
5. Proses dan kegiatan yg hasilnya dpt mempengaruhi pelestarian kawasan konservasi SDA dan atau perlindungan cagar budaya
6. Introduksi jenis tumbuhan, hewan dan jasad renik7. Pembuatan dan penggunaan bahan hayati dan non-
hayati8. Penerapan teknologi yg diperkirakan mempunyai
potensi besar untuk mempengaruhi lingkungan
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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 dampak2. Luas wilayah persebaran dampak3. Lamanya dampak berlangsung4. Intensitas dampak5. Banyaknya komponen lingkungan lainnya yg akan
terkena dampak6. Sifat kumulatif dampak7. Berbalik (reversible) atau tidak berbaliknya dampak
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.