In Indonesia, an EIA (environmental impact assessment) — locally AMDAL (Analisis Dampak Lingkungan) — is the legal and practical gatekeeper for oil and gas exploration. The playbook is rigorous: baseline the land, water, air, wildlife, and people; model the impacts; and negotiate a social license in public.
For upstream oil and gas in Indonesia, the AMDAL isn’t paperwork — it’s the project’s first real stress test. Indonesian law makes a full EIA mandatory for major upstream projects “with potential to cause large and important environmental impacts” (kanal.web.id). Government regulation and ministerial lists set thresholds — for example, onshore gas fields at or above 30 million standard cubic feet per day require an EIA (pdfcoffee.com).
The timing is early. Once a PSC (production sharing contract) is signed, contractors must run an Environmental Baseline Assessment (EBA) before drafting the AMDAL’s full impact analysis (researchgate.net) (researchgate.net). That analysis threads into an Environmental Management Plan (RKL) and Monitoring Plan (RPL), which Indonesian practice uses to manage and track significant impacts (pdfcoffee.com). The intent is explicit: use data — air and water quality, species inventories, socio-economics — so no “adverse impacts to human health and the environment” result (yumpu.com).
The process is standardized: scope the issues; run multi‑disciplinary baseline studies across the physical, biological, and social environment; predict impacts with models; design RKL/RPL; and consult the public — with international IFC/World Bank guidance commonly referenced (yumpu.com).
Regulatory scope and workflow
Indonesia’s AMDAL rules apply across onshore and offshore exploration and development. Thresholds — like the ≥30 million scf/d example for onshore gas — trigger a mandatory EIA submission (pdfcoffee.com). The EIA’s core components are scoping, baseline studies, impact prediction, and RKL‑RPL, followed by public consultation, which together anchor regulatory review and ongoing oversight (pdfcoffee.com).
Contractual requirements pull baseline work forward. Operators undertake an Environmental Baseline Assessment when a PSC is executed and then develop the AMDAL with full impact analysis (researchgate.net) (researchgate.net). Guidance from IFC/World Bank on onshore oil and gas remains a reference point for how to collect baseline data, model impacts, and manage noise, emissions, and discharges (yumpu.com) (yumpu.com).
Physical environment baseline and models
Meteorology and air quality set the frame. EIA teams collect one to two years of local weather — wind, temperature, humidity — and measure ambient PM2.5/PM10 (fine particulate matter), NO2, CO, SO2, H2S, and VOCs including BTEX (benzene, toluene, ethylbenzene, xylene) around the site. Atmospheric dispersion models such as AERMOD are then used to predict the incremental impact from rigs, compressors, flaring, and transport, per IFC advice that “[air] quality impacts should be estimated by baseline air quality assessments and atmospheric dispersion models” (yumpu.com). Where greenhouse gases are large, IFC guidance calls for quantifying any facility emitting more than 100,000 tCO₂e per year and evaluating efficiency measures (yumpu.com).
Surface and groundwater come next. Surveys map river catchments and groundwater wells; sampling upstream and downstream captures pH, salinity/electrical conductivity, turbidity, dissolved oxygen, nutrients, oil and grease, and heavy metals. Spill or blow‑out scenarios are modeled for contaminant plumes. Baselines matter: for example, an unimpacted stream might show TSS under 10 mg/L and dissolved BTEX under 1 μg/L; modeling and compliance checks ensure discharges stay within Indonesian standards. Where oily water is expected, treatment trains cited in EIAs often include free‑oil separation, as with an oil removal skid (oil removal), and screening at intakes for debris control via continuous systems (automatic screen), aligned with IFC’s focus on wastewater/effluent discharges (yumpu.com).
Soil and geology are characterized — soils by texture and organic content, sites by geotechnical conditions, and landforms by erosion or slope‑stability risk from vegetation clearing. Baseline soils are tested near any cuttings pits for hydrocarbons or heavy metals. Subsurface geophysics informs where not to drill. IFC identifies “terrestrial impacts and project footprint” as key; land clearing for a rig pad or access road might span 10–50 hectares, requiring quantified sediment yield changes and re‑vegetation plans (yumpu.com).
Noise and vibration are monitored day and night at the nearest communities and modeled against WHO/Indonesian limits — for example, 55 dB(A) daytime for rural areas. Seismic detonations are assessed for structural and wildlife effects; H2S, if present, is monitored for odor continuously. IFC flags “noise generation” as a concern requiring mufflers or work curfews to meet standards (yumpu.com).
Spills and effluents are scenario‑planned. Offshore slicks are modeled under prevailing currents; onshore, containment capacity is measured and routine effluent volumes quantified. IFC’s sector guidance explicitly includes “wastewater/effluent discharges” (yumpu.com). In practice, for a typical exploration rig releasing under 10 m³/day of treated wastewater, the target is dissolved hydrocarbons below 5 mg/L per government norms. Dissolved air flotation may appear in plans where suspended solids and residual oils must be removed efficiently (DAF).
In short, robust physical‑impact studies blend field monitoring of air, water, soil, and noise with dispersion, hydrologic, and spill‑trajectory modeling to meet ambient standards and IFC best practices (yumpu.com) (yumpu.com). For exploration camps drawing on local surface waters, pretreatment that strains pathogens and fine solids is often cited — ultrafiltration is a standard pretreatment step for downstream RO or drinking applications (ultrafiltration).
Biological environment studies
Indonesia’s biodiversity demands depth. Terrestrial surveys deploy vegetation transects and plots to catalog plant communities and health; wildlife teams use camera traps and line transects to record mammals, birds, and reptiles, watching closely for endangered or endemic species. Indonesia hosts 732 mammal and 1,711 bird species (14–17% of global totals), underscoring the stakes (dicf.unepgrid.ch). Habitat mapping via satellite imagery and on‑foot checks identify primary forest, peat swamp, or savanna, plus wildlife corridors and protected areas.
Freshwater ecology assessments survey fish, amphibians, and macroinvertebrates, and measure seasonal river flows, riparian vegetation, and bank stability. Reference streams help flag change — a drop in diversity from, say, a typical Indonesian mountain stream’s community can signal impact.
Marine and coastal studies map underwater habitats end‑to‑end: coral reefs (percent live coral cover and species richness), mangroves, seagrass beds, and benthic invertebrates. Indonesia contains about 569 coral species (20% of the world’s total) and 3.3 million hectares of mangroves (dicf.unepgrid.ch) (dicf.unepgrid.ch). For seismic surveys, specialized acoustic studies gauge effects on fisheries and marine mammals; fish stocks are quantified where livelihoods depend on them.
Sensitive ecosystems or protected zones — national parks, wildlife sanctuaries, or indigenous sacred sites — raise the bar. Overlap with biodiversity hotspots or Important Bird Areas can trigger stricter mitigation such as expanded buffer zones. Cumulative impacts and invasive species risks are also assessed, with long‑term monitoring often specified for years after construction.
Social and economic baseline
Demography and settlement patterns define the Area of Influence. EIAs map villages and hamlets, pull census data on population, age, education, and ethnicity, and project forward for the asset’s life. A remote block might affect 3–5 villages totaling 2,000 people — a scope that drives the breadth of consultation.
Livelihoods are quantified. In coastal or rural areas, households may rely heavily on fishing or agriculture; Indonesia is the world’s second‑largest fishery producer (dicf.unepgrid.ch). EIAs compare expected benefits like jobs and local procurement with potential losses such as fishers’ access limits from pipelines. Example statistics are common for clarity — “200 households (85%) engage in fishing, generating average monthly income of 1.5 million IDR.”
Land tenure and land use are mapped in detail, including customary (adat) claims and current uses such as fields, plantations, forest, and hunting grounds. Any land take or rights‑of‑way are quantified in hectares and matched with compensatory plans. Cultural and heritage assets — mosques, temples, sacred forests, archaeological finds — are inventoried and buffered or rerouted as needed.
Health baselining covers disease incidence, nutrition, and healthcare access, then projects potential effects from diesel exhaust or traffic. Drinking water and sanitation assessments ensure that project water draw doesn’t deprive communities. Offshore or isolated sites often plan for self‑supply: many EIAs describe seawater reverse osmosis for industrial uses such as power or utilities (sea water RO) and short‑term coverage via containerized units for temporary or emergency needs (rental units). For potable supply and taste/odor control, adsorption steps using granular media are frequently cited (activated carbon).
Public consultation requirements
Consultation is mandatory and consequential. Indonesian Environmental Law (No. 32/2009) required that the EIA be “formulated by the initiator by involving communities” (business-humanrights.org). In practice, regulations call for multiple events — scoping, draft EIA hearings, final disclosure — and broad advertisement of project details. A recent onshore oil‑field hearing in Sijunjung, West Sumatra, brought village chiefs, elders, and NGOs into the AMDAL process (infopublik.sijunjung.go.id). The regent said the aim was “so that the community obtains information on planned business activities that have important impacts on the environment” (infopublik.sijunjung.go.id).
The upside is practical. Early consultation typically reduces community anxiety and opposition — “When people are informed, their anxiety and concerns tend to be reduced and the project developer finds that his proposals are more readily accepted” (sdnp.org.mw). Locals also contribute data that outsiders miss — sacred forests, medicinal plants — and suggest culturally appropriate mitigation, which “helps avoid EIA omissions and mistakes” (sdnp.org.mw).
The risks of getting it wrong are visible. Critics of Indonesia’s Omnibus Law warned that limiting participation to “only those directly affected” could disenfranchise activists and indirectly impacted neighbors (business-humanrights.org). Farmers and NGOs have litigated approvals where outreach fell short; one prominent case, the Kendeng dispute over a cement plant, centered on AMDAL participation (business-humanrights.org). In the oil and gas context, “social license to operate” is earned at these meetings, not after.
Management plans and business certainty
The RKL (Environmental Management Plan) and RPL (Monitoring Plan) distill everything — air and water data, species records, socio‑economic surveys — into executable controls and monitoring routines, which is how Indonesia operationalizes AMDAL findings (pdfcoffee.com). For camps and wellsites, those plans often reference treatment trains that align with IFC guidance on “wastewater/effluent discharges” (yumpu.com), such as compact biological systems that pair with ultrafiltration membranes for reuse‑quality water when required (membrane bio‑reactors (MBR)).
The commercial logic is straightforward. Evidence from E&P projects shows that early community engagement and transparent EIA processes deliver schedule certainty; studies estimate 30–50% fewer delays from social disputes when stakeholders are consulted early (sdnp.org.mw) (sdnp.org.mw). With Indonesia expecting oil and gas investments to rise on a focus on boosting exploration — even as challenges such as decarbonization loom — process certainty matters (reuters.com).
What the documentation anchors
Across sections, the EIA/AMDAL threads constants: the IFC/World Bank’s onshore oil and gas guidance on air quality baselines and modeling (yumpu.com), greenhouse gas accounting above 100,000 tCO₂e per year (yumpu.com), terrestrial footprint accounting (10–50 ha) and noise controls (yumpu.com), and wastewater/effluent discharge management (yumpu.com). Where exploration is offshore or remote, self‑sufficiency in water and sanitation is documented — reverse osmosis for seawater utilities (sea water RO), with temporary or emergency coverage as needed (containerized SWRO rental units), and polishing steps for organics before distribution (activated carbon).
Sources and statutory references
Indonesian laws and ministerial regulations define AMDAL requirements and thresholds, including PP 27/1999 and PermenLH 11/2006 (pdfcoffee.com) (kanal.web.id). The IFC/World Bank guidance for onshore oil and gas provides sector good practice for baselining and impact modeling (yumpu.com) (yumpu.com). Baseline obligations in Indonesia’s PSC context are detailed in EBA references (researchgate.net) (researchgate.net). Biodiversity and fisheries statistics are from government and peer‑reviewed sources (dicf.unepgrid.ch) (dicf.unepgrid.ch) (dicf.unepgrid.ch). AMDAL cases and participation debates — including the Sijunjung hearing and Omnibus Law concerns — are cited (infopublik.sijunjung.go.id) (infopublik.sijunjung.go.id) (business-humanrights.org) (business-humanrights.org) (business-humanrights.org). Consultation principles and their business impact are sourced from EIA guidelines (sdnp.org.mw) (sdnp.org.mw).
