(CBS News) STRATFORD HALL, Va. -- This summer, scientists and volunteers are digging up something really big on the shores of the Potomac.
"I saw a portion of a bone sticking out of the cliff about 3 feet above where the cliff meets the beach," said Jon Bachman.
Bachman has been hunting for fossils along the Potomac River for 25 years. But this summer, he made a huge discovery.
He found a portion of a skull, and says his excitement scale was a "10" on a 10-point scale, because he had never seen something that big.
It turned out to be the skull of a whale that lived here 14 million years ago when the area was under the Atlantic Ocean.
Scientists and volunteers have spent countless hours meticulously scraping away sediment, hoping to uncover the entire whale, estimated to be 25 feet long.
High school junior Paige Fischer says it's addictive -- she's been hooked on fossils since she was three years old.
"[It's] kind of like a treasure hunt in a way. You never know what you are going to find. You just walk along the beach. Maybe you'll find a whale skull, maybe a little shark's teeth," said Fischer.
The whale is being removed piece by piece, wrapped in a white plaster cast, and sent to the Calvert Marine Museum in Maryland where they use dental tools to slowly uncover the whale's story.
"We found a number of shark teeth with the skeleton so there is a halo of shark teeth around the skull," said paleontologist Stephen Godfrey.
He says the whale appears to be an extinct relative of the pygmy right whale. It's also related to the much larger blue whale.
Back on the beach, Bachman can still hardly believe his luck in stumbling across the discovery of a lifetime.
"This is a piece of the earth's history that has come to light," said Bachman.
A piece of history full of secrets now being painstakingly revealed.
"Photograph of Pygmy right whale (Caperea marginata) by Robert Pitman, NOAA Fisheries, http://eol.org/data_objects/8920266, CC BY-NC-SA 3.0"
"Photograph of Blue Whale with Calf by Andreas Tille, http://eol.org/data_objects/25599600, CC BY-SA 3.0"