Introduction

The deindustrialization of cities throughout the 20th century has left behind a vast legacy of abandoned factories and brownfields embedded within urban fabrics. These post-industrial landscapes, while often carrying significant architectural, historical, and identity values, are frequently subjected to complete demolition or simplistic land-use changes, leading to severe soil, water, and air pollution alongside socio-economic decline. Contemporary approaches, however, advocate for conservation-based redevelopment, transforming these sites into green public spaces to enhance urban liveability. A thorough review of the existing literature reveals a critical research gap: previous studies have predominantly addressed environmental remediation, structural restoration, and ecological design as separate, siloed processes, failing to provide a replicable, integrated methodological framework that harmonizes these three domains simultaneously, particularly in the Middle Eastern context and Iran. Consequently, the primary objective of this study is to develop a comprehensive methodological framework for designing a post-industrial site museum, orchestrating the concurrent integration of environmental cleanup, industrial heritage conservation, and landscape redesign. The core innovation of this paper transcends the mere theoretical integration of these fields; it operationalizes a field-data-driven process—encompassing systematic sampling, laboratory analysis, Geographic Information Systems (GIS), and Multi-Criteria Decision Making within a concrete case study (the Pars Vegetable Oil Factory). This approach replaces the prevailing demolition-oriented perspective with a conservation-development model, offering a scalable and replicable blueprint for similar abandoned industrial sites across Iran.
Materials and methods
The study focuses on the Pars Vegetable Oil Factory, located in District 16 of Tehran (Khazaneh neighborhood). The 45,000 m² site was established in 1954, operated for decades, and was permanently shut down in 2015. It comprises various industrial units (chemical and physical refining, can-making, power plant, packaging, and warehouses) and currently represents a heavily contaminated brownfield.
Environmental Sampling and Analysis Protocols: Soil Sampling and Analysis: A systematic grid sampling protocol (100 m × 100 m) was implemented, yielding 14 composite samples collected from a depth of 0–50 cm using stainless steel augers. After air-drying, homogenization, and sieving (2 mm mesh), samples underwent acid digestion. Heavy metal concentrations (Lead (Pb), Chromium (Cr), and Nickel (Ni)) were determined using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Total Petroleum Hydrocarbons (TPH) and Polycyclic Aromatic Hydrocarbons (PAH) were extracted using ultrasonication with dichloromethane and analysed via Gas Chromatography-Mass Spectrometry (GC-MS) following the EPA 8270E method. Groundwater Analysis: Water samples were collected from two 2-meter-deep monitoring wells equipped with PVC casings and screened intervals. Physicochemical parameters, including nitrates, ammonia, phosphates, sulphates, heavy metals, oils, grease, and Chemical Oxygen Demand (COD), were analysed using established laboratory protocols. Air Quality Assessment: Passive air sampling was conducted at three locations over a 10-day period. Asbestos fibbers were quantified using Phase Contrast Microscopy (PCM), particulate matter (PM₁₀ and PM₂.₅) was monitored using portable aerosol monitors, and Volatile Organic Compounds (VOCs) were analysed via GC-MS.
Heritage Documentation: A comprehensive archival investigation (National Archives of Iran and municipal records) was performed. Structural documentation employed Total Station surveying for precise mapping and photogrammetric recording of significant structures. A 4-point condition assessment scale (1=Excellent to 4=Ruined) was utilized for structural integrity evaluation, alongside cross-referencing historical documents for element identification. · Landscape Zoning and Spatial Analysis: Multiple data layers—including topography, hydrology, land use, vegetation, contamination intensity (based on lab results), heritage values, and infrastructure—were prepared. These layers were subsequently overlaid in ArcGIS Pro using a Weighted Overlay Analysis based on the Analytical Hierarchy Process (AHP). This spatial MCDM facilitated systematic landscape zoning and the formulation of tailored planning and design strategies for different site sectors.
Results and discussion
Environmental Contamination Findings: Soil: Heavy metal concentrations significantly exceeded national environmental protection standards: Pb (96–430 mg/kg), Cr (65–320), and Ni (85–215). TPH concentrations ranged from 230 to 4,500 mg/kg, exceeding the 190 mg/kg standard in 80% of samples. Total PAH concentrations (prioritized 12 compounds) ranged from 4.2 to 107.6 mg/kg, surpassing standards in 80% of cases, with hotspots identified near former fuel storage tanks and maintenance areas. Groundwater: The analysis of the two monitoring wells revealed extremely high levels of pollutants, including COD (3,600 mg/L), BOD₅ (2,200 mg/L), and oil & grease (1,760 mg/L), alongside elevated nitrates, ammonia, and heavy metals. Critically, three active qanat waterways run beneath the factory, indicating a severe risk of contaminant migration to residential areas. Air: Field observations and analyses confirmed the presence of hazardous airborne asbestos fibbers from degraded pipe insulation, inhalable silica dust from spent bleaching clay, and explosive/volatile gases (hexane, hydrogen) posing significant detonation and respiratory risks.
Heritage Significance and Conservation Priorities: The documentation process identified substantial heritage value in the Pahlavi-era architectural structures, monumental industrial machinery (presses, refining tanks, packaging lines), and mature trees within the compound. These elements are irreplaceable carriers of the community's collective memory and urban identity. Methodological Integration and Design Strategy: The integrated analysis (environmental, heritage, and spatial) enabled systematic landscape zoning. The resulting strategic master plan comprises several key interventions: elimination of incompatible modern additions; comprehensive decontamination (physical, chemical, biological); and revival of ecological connectivity. The visitor circulation route is meticulously aligned with the historical oil production flow, from raw seed reception to packaging. The design proposes sensory stations (olfactory installations simulating safe scents of toasted seeds and chemicals), adaptive reuse (converting warehouses into galleries/libraries, press halls into museums, and administrative buildings into museum offices), and the creation of cultural open spaces (theatre/concert areas). The remediation strategy specifically employs phytoremediation (using selected species: poplar, willow, canola, sorghum based on prior climate-compatible studies for heavy metal uptake), bioremediation (microbial degradation of organics using Pseudomonas and Bacillus strains), and physical stabilization/solidification.
This research demonstrates that an integrated spatial integration of environmental and heritage data enables a design that is both ecologically responsive and culturally resonant. A pivotal conceptual innovation introduced here is "conditional conservation" a paradigm where heritage structures in irremediable contamination zones are isolated, while non-valuable structures in clean zones are adaptively redesigned. Furthermore, the three-layered interconnection of soil, water, and air is addressed by highlighting the threat of runoff from contaminated surfaces to groundwater (via qanats), directly influencing the site's drainage and stormwater management design.
Conclusion
This study successfully implements a comprehensive causal-decision chain, bridging the historical gap between raw environmental data and concrete landscape design for the first time in an Iranian brownfield (specifically within the edible oil industry). The findings validate that conservation-based redevelopment, as opposed to demolition or pure change of use, effectively achieves environmental cleanup while fostering socio-cultural regeneration, improving community interaction, and enhancing public awareness of industrial heritage. The proposed master plan for the Pars Oil Factory, integrating phytoremediation, machinery conservation, and educational pathways, provides a robust, replicable model for analogous sites. Crucially, the design elevates the remediation process itself into a core narrative of the museum, transforming it from a mere design project into a site-based environmental education tool. By operationalizing the spatial integration of contradictory criteria (heritage value vs. biological threat) within an AHP decision model, this research redefines conservation as contingent on environmental health, offering a novel pathway for urban policymakers towards sustainable, participatory, and regenerative management of post-industrial urban landscapes.