Truckee Fire Protection District and Placer County Environmental Health are still working to ensure that all properties in the Serene Lakes community affected by leaking propane systems are cleaned up. Several properties remain unabated, so the incident command team left in place the voluntary evacuation order.

Since March, there have been 42 properties affected by propane in the Donner Summit community that have leaked from storage tanks and the plumbing that connects the tanks to houses. Three active sites remain; the rest have been mitigated.

The voluntary evacuation order underscores the inability of public safety agencies to guarantee that the area is absolutely safe from any ill effects of propane. The area cannot be declared “safe” until all of the snow in the Serene Lakes area has melted or additional monitoring is completed showing that there are no hazardous concentrations of propane left near the leak sites. The cooperation of property owners at properties where hazardous levels of propane have been found is tantamount in getting these areas declared safe.

Passive dissipation (natural evaporation of propane) can be effective, however it comes at the expense of a safe environment for neighbors. Propane and gas systems (tanks, regulators and piping) still buried in the snow may hide potential leaks. Property owners need to ensure the safety of their properties by clearing snow from around their propane systems.

Extraordinary snowpack this season has created the leaks when the weight of dozens of feet of snow and ice broke plumbing between tanks and houses. Two other homes in other areas of eastern Placer County were also affected by leaking propane, however, those sites have been remediated.

There may still be undiscovered leaks in the Serene Lakes area. Even in areas where the propane systems are exposed, it is possible for propane to be trapped under the snow. As propane is heavier than air, it will follow a path of least resistance, and can travel long distances under crusted snow.