Case Studies
PCS Nitrogen, a business unit of Potash Corporation of Saskatchewan, is one of the largest producers of nitrogen worldwide. It produces nitrogen fertilizers and feed ingredients from three manufacturing facilities in the US and one in Trinidad. When they experienced heavy contamination of soils with hydrocarbon and TPH compounds at two of their facilities, they utilized Ecological Laboratories’ MICROBE-LIFT® technology to remediate these sites.
We would like to thank you for allowing us to include your product, Microbe-Lift, in our bioremediation test project. Microbe-Lift was used along with several other products to investigate the oil degradation process of non PCB transformer oil.
MOSTARDI-PLATT ASSOCIATES, INC. (MPA) has prepared this letter to inform you of the preliminary results of a controlled experiment involving the full-scale field application of Microbe-Lift for remediation of petroleum contaminated soils. In this experiment, four relatively uniform soil cells, with volumes of approximately 30,000 cubic feet each, were to be remediated by bioremediation. The contamination involved was a heavy fraction of petroleum.
Use of the vehicle workshop area at the Frito-Lay Simba Isando plant was discontinued due to outsourcing of the distribution chain. An area in front of the wash bay bordered by the workshop and boundary walls had been heavily contaminated by hydrocarbon. This contamination was a mix of petroleum (PRO) and diesel (DRO) range organics and covered a surface area of approximately 300 square meters. The contamination occurred in three main areas, these being DRO in approximately 30 square meters under the removed diesel tank, a mix of DRO and PRO in approximately 120 square meters in front of the wash bay and an area of approximately 90 square meters of tar macadam covered soil. The wash bay area was contaminated with a mixture of petroleum, diesel,oils, alkanes and kerosenes. During initial sampling the average depth of contamination was found to be 150 mm below the surface, a target depth of remediation was set at 250 mm below the surface. In order to re-use this ground the company requested they bioremediate the soil to a value below a total petroleum hydrocarbon (TPH) value of 2000 mg/kg. This value was chosen based on the fact that the site was industrial and would not readily be used for agriculture or human occupation in the foreseeable future. Another factor affecting this target is that the Department of Water Affairs and Forestry (DWAF) had in the past recommended the use of a similar target for hydrocarbons in an industrial area (Snyman 1996). The area was completely enclosed by concrete walls on three sides and a brick workshop on the remaining side. Thus, in-situ bioremediation was the preferred method providing the following benefits:
Ecological Laboratories has addressed wastewater technology internationally for over ten years. In that time they have remediated a variety of petroleum contaminated sites including oil production ponds in Venezuela for GEBetz, containment ponds in Israel, and sites in the Dominican Republic and throughout Asia. In this case, a major oil company, who chooses to remain anonymous, had detected contaminated soil under a concrete slab at an oil transportation and transfer site. The oil had seeped into the ground to a depth of two meters.
The plant is tied into the municipal wastewater treatment system. The plant had been in operation for several years and complaints from the city residents and government officials had been escalating because of the extremely unpleasant odors that were being emitted by the plant. Residents living near the plant began to complain about discoloration of window blinds and shades. Many reports of headaches and sore eyes began to surface. A determination was made that the high levels of hydrogen sulfide being emitted by the plant, either directly into the air due to an inadequate air scrubber systems, or as a result of effluent discharge into the wastewater sewer system, was the major cause of the yellowing effect on the blinds and shades as well as the source for the offensive odors in the air which could be associated with the high level of reported headaches and sore eyes.
