Rio Algom Limited & Denison Mines Inc. Community Newsletter 2016 Elliot Lake Dams: Dam Safety and Emergency Response Dams play an important role in tion of cracks in the surface, or the In addition to the substantial effort A high water table (close to the sur- the safe operation of both Rio Al- effects of erosion such as wind or that RAL and DMI apply to main- face) at the Pronto TMA serves to gom Ltd. (RAL) and Denison Mines water. Further, the dams are kept taining the Elliot Lake dams, both reduce acid generation. However, Inc. (DMI) closed mine sites. Most free of any vegetation as penetra- companies have focused their ef- in the eastern portion of the TMA, of the tailings management areas tion of roots can undermine dam forts in the area of emergency re- the saturation extended to surface are submerged in order to pre- stability. Finally, annual geotechni- sponse planning for the sites. In which hindered traditional direct vent them from oxidizing (react- cal Dam Safety Inspections (DSIs) 2016, RAL and DMI have conduct- liming and seeding and as such a ing) with open air, and a system of by the engineers-of-record are ar- ed several joint exercises with the successful vegetative cover could dams, berms, dykes and spillways ranged in order to ensure the dams City of Elliot Lake and various first not be maintained. To resolve this helps maintain the water cover. stay within design specifications responders to improve and better problem, rock-lined drainage ways All dams in the Elliot Lake area are for all of the above-mentioned risk integrate the emergency prepared- were installed in the eastern por- subject to a rigorous program of factors. ness of all parties in the event of tion of the TMA during the winter dam maintenance. The dam main- a potential incident at one of the of 1999 and 2000. Then six tonnes/ tenance program involves inspect- Every five to seven years, RAL and sites. ha of limestone and 500 kg/ha of ing the dams for any evidence of DMI also contract an additional fertilizer were applied to bare ar- structural distress including shift- safety study by third-party engi- eas in the spring of 1999 and a 30 ing or slumping of the dam, forma- neers in order to comply with ap- cm depth of biosolids (in the form plicable regulations and ensure of paper mill sludge) were spread dam safety. These studies are called over a 20.9 ha area from 1999 to Inside This Dam Safety Reviews (DSRs) and are 2001. These measures have been systematic reviews and evaluations effective in maintaining a 100% Newsletter... of all aspects of design, construc- vegetative cover following pro- • Elliot Lake Dams: Dam tion, maintenance, operation, and Denison Mine - Dam 10 gram completion in 2001. Safety and Emergency surveillance, along with other fac- Current activities at the site in- Response tors, processes and systems affect- Pronto: A History clude seasonal water treatment • Pronto: A History ing dam safety. The DSR includes through a lime treatment plant, re- • Quirke Lake Fire all components of each “dam sys- moval of vegetation from site dams, inspections of the cover and facil- • Water Quality in tem” including the dam itself, spill- The Pronto tailings management area (TMA) is located on the north ity conditions, and environmental the Serpent River way, foundation, abutments, and even the tailings management area side of Highway 17, approximate- monitoring. The site complies with Watershed being maintained. The most impor- ly 10 km east of Blind River. The all environmental regulations and • Community Interaction tant aspect, is that the DSR evalu- Pronto mine operated from 1955 licences and has been an excel- with Closed Mine Sites ates the system based on current to 1960 during which, the Pronto lent example of mine closure done Penokean Hills Field standards. The current standards mill processed approximately 2.1 right in Ontario. Naturalists may be different from the accept- million tonnes of uranium ore. In • Watershed Monitoring able standards that were in place at 1960, the mill was converted to Map the time of original construction. process copper ore, producing ap- • Owners and dogs: If a system, structure, or process proximately 2 million tonnes of copper tailings between 1960 and Responsibilities on is inadequate, the upgrades are performed as a result of the DSR, 1970. The tailings were deposited closed mine properties so that the Elliot Lake dams are al- in a 47-hectare natural rock basin • Hiking on Mine ways maintained to the best cur- (contained by Dam A) construct- Property rent practices for dams in Canada. ed of glacial till with a waste rock • Keeping in Touch shell. Rehabilitated Tailings Area with Biosolids Pg 2 Quirke Lake Fire in the plant and regular operator surveillance; daily inspection of On May 24, 2016 at approximate- the water quality released from the ly 1 pm, a local resident boating plant; and extensive downstream on Quirke Lake noticed smoke in monitoring. the bush between Quirke Lake and the Denison closed mine site. The Every five years, the environmental resident notified the Elliot Lake monitoring data from the tailings Fire Services (ELFS) which imme- management areas and the down- diately initiated its response to the stream environment is reviewed fire. John Thomas, Elliot Lake Fire by a third party consultant who MNR Water Bomber with Rooster Rock in background Services Fire Chief, contacted the specializes in water quality and en- Ministry of Natural Resources and vironmental impacts. This review Forestry (MNRF) to request sup- is documented in a report called port. By approximately 2:25 pm, the “State of the Environment Re- the ELFS team had arrived at the port” which is submitted to regula- site to commence their initial at- tory agencies and, following regu- tack and by approximately 3:45 latory comments and approval, is pm, the MNRF support team which available to the public either at the included a team transported by Elliot Lake library or by contact- helicopter, a fixed wing support ing the RAL or DES offices in Elliot plane and an MNRF water bomber Lake. The most recent state of the were at the site. The water bomber environment report is currently began dropping water onto the under regulatory review and will fire at 3:50 pm and completed its be finalized and released later this last drop at approximately 4:20 year; however, some of the high- pm and at that time, the fire was Drone shot of fire damage lights are discussed further below. substantially out and under con- trol. A total of 61,300 litres of wa- Water quality in the tailings man- ter was dropped onto the fire. The Water Quality in the Serpent River agement areas has continued to total area burned by the fire was improve since the completion of approximately 3 hectares (HA) Watershed site closure work in the 1990s. In which is relatively small thanks to the downstream environment of the quick action of the ELFS and Rio Algom Ltd. (RAL) and Denison ment plants. After the contami- the Serpent River Watershed, all of the MNRF. To give some perspec- Mines Inc. (DMI) operate eight wa- nants are removed, the clean water the water quality parameters were tive of the size of the Quirke Lake ter treatment plants in the Serpent overflows from the settling ponds below the provincial water quality fire compared to the Fort McMur- River Watershed. At these sites, tail- and is eventually released into the guidelines and most samples were ray fire– the Quirke Lake Fire was ings water is collected in basins or Serpent River Watershed. within the normal regional back- 3 ha while the Fort McMurray fire collection channels and directed to Denison Environmental Services ground variability (i.e. there were was well in excess of 500,000 hect- the treatment plants where treat- (DES) works on behalf of RAL and detectable impacts from the former ares which is larger than the area ment reagents (lime and/or barium DMI to perform numerous tasks to mine sites). Overall, the tailings of the Prince Edward Island. chloride) are added to the process ensure that the water released from management areas are performing Without the quick responses of water. The treatment reagents the former mine sites (now referred as predicted during closure and the local resident, the ELFS and the raise the pH and remove contami- to as “tailings management areas”) the Serpent River Watershed water MNRF, the fire may have grown in nants from the water by binding to is clean and the environment is quality continues to remain better size. The cause of the fire was a them and forming particles that are protected. Measures include 24/7 than the government guidelines tree on a hydro pole line. settled out of the water in settling monitoring and trending of the wa- that were established to protect ponds downstream of the treat- ter treatment plants via computers human health and aquatic life. Pg 3 Community Interaction with Closed Mine Sites Submitted by Marg Reckahn, Penokean Hills Field Naturalists The Penokean Hills Field Natural- the various song birds that make ists are the stewards of the Sheriff this area their home. Creek Sanctuary. We have enjoyed many years of partnership with Rio The Penokeans keep bird feeders Algom Ltd. (RAL) and the City of full for the winter season and there Elliot Lake in regards to the Sanc- are always a lot of birds who feast tuary. This area is well used by on the seeds. the public, both local and visitors.