Case Study: Building a Sustainable Oil Pit Storage System in Kharsang, Arunachal Pradesh Using Ocean HDPE Liner – 1500 Micron

In the Kharsang oil field in Changlang district, Arunachal Pradesh, Ocean Non Wovens supplied and installed 8400 square meters of Ocean HDPE Liner 1500 Micron to line an oil pit. The site is remote, the terrain is rough and the monsoon is heavy, so the work depended as much on logistics and installation planning as on the liner itself.

Project scope

• Location: Kharsang, Arunachal Pradesh
• Purpose: Oil Pit Containment for hydrocarbon fluid segregation
• Product Used: Ocean HDPE Liner 1500 Micron
• Quantity Supplied: 8400 SQM
• Installation Timeframe: 10 working days
• Sub-grade Preparation: Compacted earth with geotextile underlayer

What an oil pit does

In upstream oil and gas operations, lined pits hold crude oil, drilling mud, produced water and other hydrocarbon-based fluids. They keep these fluids segregated and, above all, out of the soil and groundwater. The Central Pollution Control Board (CPCB) and the Oil Industry Safety Directorate (OISD) both set requirements that bear on how these pits are designed and run.

Why HDPE

HDPE is the most common geomembrane for oil pits because it is effectively impermeable to liquids, resists crude oil, brines and most acids and alkalis, and, when carbon-black stabilised, holds up to UV exposure on the exposed side slopes. A 1500 micron (1.5 mm) sheet is a common choice for containment of this kind: thick enough to tolerate site handling and welding, and heavy enough to resist puncture over a prepared earth subgrade.

Ocean HDPE Liner 1500 Micron: key properties

For comparison, the international reference specification for smooth HDPE geomembranes, GRI-GM13, requires a 1.5 mm sheet to have a density of at least 0.940 g/cc and sets minimum tensile, tear, puncture, stress-crack and oxidative-stability values. Asking for test certificates against GM13 is a simple way to compare liners from different suppliers.

How the pit was installed

Prefabricated panels

To cut on-site seaming, the team prefabricated panels to site-specific dimensions. This reduced material wastage and cut field welding time by 30%, which mattered given Kharsang’s unpredictable weather: HDPE cannot be welded on a wet sheet, so every dry hour counts.

Double-track fusion welding

Seams were made with double-track thermal fusion welding machines. Every weld was tested by air pressure and vacuum box methods in line with ASTM D4437, the practice for non-destructive testing of geomembrane seams. The double-track weld leaves an air channel between the two tracks; pressurising it (ASTM D5820) checks the full seam length, while the vacuum box (ASTM D5641) is used on extrusion welds and patches.

Geotextile underlayer

Layered geotextiles were placed beneath the liner over the compacted earth. A non-woven geotextile here acts as a cushion against sharp rocks in the subgrade and gives water or gas under the liner a path to escape instead of lifting the sheet.

Environmental care

The project was completed without harming local water sources or forest cover, working in coordination with the local environmental oversight body.

Maintenance and monitoring

After installation the client received a Quality Assurance & Maintenance Manual covering:

• Routine inspection schedule (quarterly)
• Leak detection procedures
• Emergency repair protocols
• Expected performance benchmarks over the next 20 years

Routine checks focus on the exposed liner on the side slopes and at the anchor trench, where UV, wind and mechanical damage are most likely. A damaged area on HDPE is repaired by extrusion-welding a patch over it and vacuum-testing the patch. Keeping the liner intact protects groundwater and keeps the operator clear of CPCB penalties and remediation costs.

Working with Ocean Non Wovens

Ocean Non Wovens is a geosynthetics manufacturer and supplier with over a decade of experience in manufacturing and on-site execution, covering product supply, installation and quality assurance. For oil pits, effluent ponds and other containment work, from the oilfields of Assam to the deserts of Rajasthan, contact the team with your fluid, pit dimensions and site conditions for a liner recommendation.