Submitted by Marc Ohms, Physical Science Technician
Wind Cave Bids Farewell to Candles
Starting in the 1970s, Wind Cave National Park has offered a ranger-led Candlelight Tour twice a day for the months of June thru August. The ranger and up to 10 visitors each carry a bucket with a candle for their light source. Although historically accurate and appealing to visitors, significant resource damage was occurring. Wax was leaking and dripping out of the buckets and being deposited throughout the route. Many efforts were made over the years to clean the wax from the cave, but every year more accumulated. The wax is nearly impossible to remove from hard surfaces, and to add insult to injury, the wax grows mold.
The candle bucket is simply a lard-style metal bucket with a handle fashioned onto the side so that the bucket could be carried sideways. A nail driven thru the bottom holds a candle in place. Melting wax would accumulate in the can bottom and run out the front or simply drip off the candle as the visitor aims the light downward in an effort to see the trail. The bottom lip of the bucket was bent upward and later a tuna can was added inside the bottom of the bucket to help contain wax. While these efforts helped, it did not stop the wax from being dripped along the tour route.
We needed a better solution.
Our initial goal was to try to keep using candles by buying or building a lantern that would not drip wax. After a year of trial and error we came up with nothing. The only possible solution involved the lantern having glass globes or panes surrounding the candle. Much of the Candlelight Tour route is not paved and has much more of a “wild” cave feel to it. Because of this we felt that the glass would not be a good idea as we would then be cleaning wax and glass from the cave.
After admitting defeat in finding the perfect candle lantern, we moved on to our second choice—some sort of electric light. We wanted to try to find something with a historic look to it, but most electric lanterns and lights that we found were too modern looking in appearance or light output. We then started looking at flameless candles that we could use in the current buckets. The majority of what we found was merely for decoration and cheaply made, and did not even produce as much light as a candle. Then we found our holy grail—a flameless candle that was vastly superior to anything that we had found. It is waterproof, has a rechargeable lithium-ion battery with 20-hour life,flickers like a candle, and is even a tad brighter than the real thing. Compared side-by-side with a real candle in the buckets it is really hard to tell the difference.
After 40 years of using candles to light the way, we have moved on to a much more cave-friendly approach while still being able to maintain the overall appearance of the candle and bucket. By not using candles, we have stopped this impact in the cave, are no longer generating large quantities of waste wax heading to the landfill each year, and are saving the rangers an hour after each tour that they would normally spend cleaning the wax out of the buckets. It is very gratifying to find a solution that works so well for all involved.
Series: Inside Earth – NPS Cave & Karst News – Summer 2017
Last updated: September 19, 2017