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

58

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.