spill response, site assessment and remediation of a significant gasoline release to land, resolute...
TRANSCRIPT
RPIC Montreal 2016
Rob McCullough, Stantec Consulting Ltd.
Nathanial Hutchinson, Anil Gupta Government of Nunavut, Petroleum Products Division
January, 2016
Spill Response, Site Assessment and Remediation of a Significant Gasoline Release to Land, Resolute Bay, Nunavut Challenges and Successes in the approach to remediation in a Remote Community in the Canadian Arctic
Agenda
1 Background/Initial Assessment, 2011
2 Site Assessment 2012
3 Site Remediation 2012 - Present
4 Conclusions – Challenges, Successes and Lessons Learned
Background
• Location of release • October, 2011 • Est 87,000 L of gasoline • Valve failure – day tank
overfill
Areal View of Former and Current Tank Farm in Resolute, NU
1
Site Conditions - Initial Challenges
• Stantec on-site November 2011 to assess the release
• 2 hours of daylight
• Sub zero temperatures and multi-day blizzards
• Heavy snow
• Most contractors had returned to the south for the winter
Location of Horizontal Tanks
Horizontal AST Surface Evaluation
• Fuel ran down the side of the tank and onto gravel
• No definitive evidence of fuel on the frozen ground
• Uncertainty as to whether a fuel spill occurred
• Police investigation ongoing
Snow in Catchment Basin
Snow in Catchment Basin was in excess of 4 m deep and made hand assessment difficult with no heavy
equipment available, limited visibility of hydrocarbons
Cold temperatures mitigated vapor detection
Snow was 2 to 3 m deep Hand excavation
Assessment Work in 2012 2
Rhodamine Dye Application
Applied 300 L of dye to the surface/subsurface
Test Pits in Catchment Basin
Test pits
Test pits excavated in catchment basin to assess the location of the fuel in the ice and snow
• Assessment of ice below the snow for the presence of gasoline
• Fingerprinting of fuel from samples
Test Pits in Catchment Basin (2)
Clean Ice Ice with Fuel
Ice with Fuel in Catchment Basin
Gasoline
Up to 30 % gasoline by volume in melted sample
Melted Ice/Snow
Water
Up to 30 % gasoline by volume in melted sample
Wildlife Hazards Bear Encounters
Up to 30 % gasoline by volume in melted sample
Wildlife Hazards Bear Encounters
Up to 30 % gasoline by volume in melted sample
Wildlife Hazards Bear Encounters
Test pits excavated across tank farm area and down gradient locations
Third Phase of Assessment, July 2012
Test pits
Test pits excavated across sea lift staging area down gradient of site
Very difficult to differentiate contaminants in soil
Third Phase of Assessment, July 2012
Staging area
Site Remediation 3
Silt Fence at High Water Mark
Ocean Boom in Resolute Bay
HDPE 60 mil welded liner
Cut Off Trench with HDPE Liner
Cut
-off
Tren
ch
Perforated Drain Pipe in Trench
Collection of water and phase separated product
Trenches Dug in Old Tank Farm
Approximately 5000 m3 of impacted soil placed in on-site constructed cell
On-Site Containment Cell
60 mil HDPE liner welded in the field
On-Site Containment Cell (2)
• Residual dye below tanks
• Permafrost bowl under tanks
Remedial Excavation at ASTs
Excavated to permafrost across impacted zone
Original AST location
Main Excavation at Tank Farm
Main Excavation at Tank Farm (2)
Berm from original tank farm lined and
keyed to permafrost
Exposed shale Bedrock
Excavation on Road
Backfilling of Road Excavation
Backfilling of Tank Farm Excavation
Reinstatement of ASTs
Generator, frost-biter, and fuel for equipment
Remediation Support Equipment
GAC Water Treatment System
Effluent from Water Treatment
Lessons Learned 4 • Sometimes very difficult to assess a release in Arctic
conditions even when it should be obvious
• Many Hazards to be aware of: cold temperatures, communications, wildlife, safety
• Equipment available in the south is not necessarily available in remote Arctic location, need to improvise
• Time lag on results and thus decisions
• Very expensive in all aspects
Tea + -50oC = Iced Tea
Conclusions 4
Acknowledgements
• Nathanial Hutchinson, Anil Gupta, Government of Nunavut, Petroleum Products Division
• Kristi Lowe, Director of Environmental Protection, Department of the Environment Government of Nunavut
• Patricio Fuentes, Regional Project Manager, Community and Government Services, Baffin Region, Government of Nunavut
• Patrick Kramers, Curtis Didham, Environmental Enforcement Directorate, Enforcement Branch, Environment Canada
Questions?
Robert McCullough, B.E.S., CET., CESA., EP Principal Stantec Dartmouth (902) 468-7777 [email protected]