Oil spill remediation plan gets approved

A remediation plan for the site of an oil leak near Tioga, North Dakota, US, has been approved by the North Dakota Department of Health. Around 20,600 barrels of oil spilled from a damaged pipeline onto farmland in the largest oil disaster ever seen in North Dakota. 

The spill, which occurred in September last year, was a result of a break in a Tesoro pipeline that ran underneath the farmland. The remediation plan that has now been approved hopes to return the land to its former state so that it will once again be suitable for farming. However, the process of soil remediation is likely to take some time.

A number of different options were considered for the clean-up of the area, but it was thought that thermal desorption would present the best results. This will require the digging up of the contaminated oil - which goes down around 30 feet - and running it through an onsite machine. The equipment will raise the temperature of the soil so it burns off the oil.

However, the process will also damage the soil by destroying all the bacteria and microbes found within it that are needed for the growing of crops. In order to combat this, Tesoro will be bringing in experts to remix the soil so it is still usable. It is thought that the company is working with the North Dakota State University to ensure the soil is brought back to its original productivity levels, according to Dave Glatt from the North Dakota Department of Health.

So far around 6,000 barrels of spilled oil have been recovered from the site, which is spread over 2.5 acres. Clean-up efforts were hampered during the winter as the ground was frozen for several months, meaning that earth could not easily be dug up.

It is estimated that the cost of the soil excavation and thermal treatment will be between $11 million (£6.5 million) and $15 million. According to a spokesperson for Tesoro, the company will be covering the full cost of the clean-up.