Managing resources responsibly and continuous performance improvement are core principles of Oil Search's approach to social responsibility. An innovative waste management project in PNG is demonstrating the Company's commitment to these principles and overcoming challenges.
Remote sites, underdeveloped public waste management infrastructure and lack of associated services make waste management an ongoing challenge in PNG. An independent review of waste management at Oil Search in 2012 identified opportunities for alternative approaches, including diverting food waste away from the incinerator.
Following the review Oil Search introduced a composting programme in 2013 to reduce the amount of kitchen waste being incinerated and create a resource from a waste product. A 'Hot Rot' composting unit was installed at Ridge Camp's waste management area. To make processing easier, a waste segregation programme was rolled out enabling separation of kitchen and paper waste.
The Hot Rot unit slowly turns and aerates the organic kitchen waste to encourage decomposition. To create the best conditions for decomposition, the Hot Rot includes online monitoring and control systems for moisture, temperature, pH and carbon dioxide. After 10-12 days the material has been reduced to compost where it is then stored for 1 month before its ready for use.
The composting initiative presented several challenges. Hot Rot units are manufactured overseas. During the bumpy three-day journey from Port Moresby Port to Ridge Camp, the unit was damaged and the repairs meant it was one year before the unit was operational. After installation, considerable innovation was required to optimise its operation throughout 2014. With no similar units in PNG, there was no guide to calibrating the equipment to counter local conditions such as high rainfall and humidity levels, which made the compost too wet.
To counter this, a dewatering unit, extra drainage and a protective roof were added. A new concreted area allowed the compost to dry better and installing a biofilter solved an initial odour problem. Woodchips were added to improve compost quality, with some experimentation to establish the best ratio of food waste to woodchips. When oversized woodchips clogged up the unit, mesh screens were installed to capture them.
As well as decreasing the risk of incinerator repairs or replacement, the Hot Rot unit has reduced the amount of waste going to landfill. The highly fertile material is used as part of the revegetation programme for closure of old drilling sites. Trials for the use of the material for vegetable gardens have been very successful and the next step is to commence supply and use of the material for local community gardens as a community development initiative.
The project demonstrates that, with commitment and innovation and by being willing to go beyond the regulatory minimum, the waste cycle loop can be closed in the remotest areas and waste turned into a useful resource.