What's That Stuff In the Water?

Image: A dye tracer test at work in a stream (Dominion Virginia Power).

If you see something strange today in the waters around Reagan National Airport, don't worry - it's just a test.

Dominion Virginia Power announced this week that it planned to release a non-toxic dye Thursday morning near the Roaches Run wildlife refuge to assess the damage to the environment caused by an oil spill in January. 

The 13,500 gallons of mineral oil leaked from a transformer at the power company's Crystal City substation and fouled the wildlife refuge and the Potomac River, reaching all the way down to the Woodrow Wilson Bridge, the Washington Post reported.

The U.S. Coast Guard was called in to clean up the Jan. 24 oil spill, which led to the death of 21 birds, mostly Canada geese, at Roaches Run, the Post reported. The wildlife refuge is in a lagoon just north of the airport along the George Washington Parkway, and its waters flow into the Potomac.

Dominion is working to remediate the environmental damage caused by the oil spill under the supervision of the Virginia Department of Environmental Quality. As part of that effort, the power company said it's conducting the dye tracer test on Thursday to determine how the mineral oil flowed from the substation into Roaches Run. 

The dye will have an "effervescent" color, likely bright peach, and will be completely safe, posing no threat to people, animals, plants or aquatic life, Dominion said.

A similar dye is released every year into the Chicago River to color it green as part of the city's celebration of St. Patrick's Day, the power company said.

Dominion said it will release the non-toxic dye over a one- to two-day period. If it reaches Roaches Run, the dye may not be visible for several days, and then it could take several days to dissipate.

The power company said it will place charcoal packages along the path of the dye "to help give us an idea of the route and the speed that the [mineral] oil would travel."