Blackdog Remediation

Blackdog landfill is located 8km north of Aberdeen City Centre, around 13.3 hectares in size (Fig. 1). It was used between the 1930s and 1990s for domestic, commercial, industrial waste - operated by Shanks and McEwan (Contractors) Ltd and Shanks and McEwan (Northern) Ltd until 1993 when the waste disposal license was surrendered. The industrial waste dumped at this landfill included liquid wastes, largely oil based drilling muds from oil exploration and production in the North Sea (Golder Associates, 2011). It is estimated that Blackdog landfill handled 70% of offshore waste that landed in North-East Scotland between the 1930s and 1980s (Robertson, 2019).

Some time after the waste disposal license was surrendered, local residents and recreational users at Blackdog observed oily liquids leaching out onto the sand dunes and beach. It was found that oils from toxic waste in the landfill were 'mobilising' - moving under the sand dunes and onto the beach. In 2004, the site was issued with 2 determination notices by Aberdeenshire Council under Part IIA of the Environmental Protection Act 1990 relating to Contaminated Land (under the Contaminated Land (Scotland) Regulations 2000). One notice was for the landfill area, and the other for the adjacent sand dunes and beach east of landfill (Golder Associates, 2011). 

It was determined that hydrocarbons were entering the water environment in the following ways (Aberdeenshire Council, 2010a; 2011):
1. Episodic pollution - during times of extreme weather (including heavy rain and flooding) which caused erosion of the sand dunes and beach. 
2. Chronic pollution - discharge of free phase hydrocarbons into the water environment, e.g. into groundwater.
Fig. 2 details a summary of the pollutant sources, pathways (i.e. how is the pollutant moving), and receptors (i.e. area of environment impacted by pollutants) (Golder Associates, 2011).

Blackdog Salmon Fisheries claim to have been impacted by the pollution from the  Blackdog landfill site, leading to its eventual closure. In 2007 the fishery caught 12 fish versus the 1200-1500 expected, and it is theorised that the salmon were avoiding oily areas of pollution (BBC, 2008; Robertson, 2019)

In 2008 it was announced that WRG were working with Aberdeenshire Council on a solution, awaiting on determination on a planning application and remediation statement before remediation works were allowed to go ahead (BBC, 2008). Environmental monitoring was undertaken, for examples measuring hydrocarbon presence/levels, beach sediment, water and LAPL (light non-aqueous phase liquid, a groundwater contaminant). The Blackdog burn was diverted in November 2008 to stop it coinciding with the beach directly east of the landfill (Goldman, 2011). In 2011, the Blackdog Interpretative Report was released following site investigation and monitoring. 

In 2019, a project by FCC Environment UK was created and approved to remove the waste. The project aims to install a plant and equipment in order to extract waste via pumping, treat the waste, and then return treated water to the ground. There is an unknown timescale for completion of this work (Robertson, 2019).