Joyce Rush still remembers seeing the swirls of blue and pink in a glass of water drawn from her family's well.
She recalls how bottled water became a staple in her family's Jacksonville home, how her son would hesitate before accepting a drink of water when visiting neighbors.
"He'd always ask, 'Where did that water come from?'" she said.
More than two decades after she learned that her well had been fouled by gasoline, Rush is once again concerned. She lives downhill from an Exxon station where more than three tanker trucks' worth of gasoline leaked into the ground - the latest in a long run of threats to the drinking water in her northern Baltimore County community.
The Jacksonville area is a mix of farms, old country manors and newer subdivisions. Cows graze in rolling pastures less than a mile from the community crossroads known to just about everyone as Four Corners, where Safeway shoppers sip lattes at the in-store Starbucks. Everybody and every business there relies on well water.
Jacksonville is also a place where residents have contended with "plumes" of gasoline contamination, with the toxic remnants of a long-abandoned Army missile base and, more recently, with the spread of the gasoline additive methyl-tertiary butyl ether, commonly known as MTBE.
And now, 25,000 gallons of Exxon gasoline in the ground.
"This is something that happens in an industrial area," said Claud Gamble, a Jacksonville native whose insurance company office is next to the Exxon station. "You hear about areas eligible as Superfund sites, but you don't think about places like Jacksonville."
The leak at the gas station was reported Feb. 17. But a review of the station's inventory records shows that the leak apparently began more than a month earlier, Herb Meade, an administrator for the Maryland Department of the Environment's oil control program, has said.
Meade said Friday that monitoring wells at the station showed MTBE levels to be at 500,000 parts per billion - or 25,000 times MDE's "action level" for the substance.
"I've seen nothing like this," Meade said of the readings.
Meade said the department's "biggest concern" is that if the MTBE reaches private wells, the contamination might be greater than a filter can readily handle.
Laboratory tests have found that MTBE can cause cancer in laboratory animals at high doses, but its health effects when ingested in low doses are unknown.
The department has, in recent years, been looking into elevated levels of MTBE at a bank, a dry cleaner and a veterinary hospital in Jacksonville, records show.
Meade has said that the gasoline leak at the Jacksonville station appears to have begun after a contractor performing maintenance on an underground storage tank system drilled a hole about the diameter of a pencil into a pipe.
The Jacksonville Exxon, at Jarrettsville Pike and Paper Mill Road, is now surrounded by a chain-link fence and orange plastic netting. The lot is filled with large tanker trucks and bulldozers.
Exxon Mobil Corp. is passing out cases of bottled water and is testing wells on Jarrettsville Pike and Robcaste Road, where Joyce Rush lives. It has set up a hot line to answer questions and, according to a letter to homeowners, is working to recover as much gasoline as possible and determine how far the fuel has migrated.
The Jacksonville Exxon station opened in 1984 - after the closing of an Exxon just down the road. A gasoline leak at that station was discovered in 1981, when a woman reported tasting gasoline in her water, and county and state environmental officials tested and found contamination in nearby wells.
Exxon reported in 1981 that an estimated 700 gallons of gasoline had been lost from a leaking underground tank at the station between March 1979 and October 1980, records show.
Rush said she had been in her home for about six months when traces of gas were found in her well.
"We could never smell it," said Rush, who as a real estate agent sold houses in the development.
In 1983, a Baltimore county jury held Exxon responsible for the leakage of at least 1,400 gallons of gasoline from corroded storage tanks at its Jacksonville station, and awarded $1.82 million to nearby property owners. Two other fuel companies settled out of court, according to news accounts at the time.
Afterward, Exxon, along with Chevron Corp., which assumed responsibility for a Gulf station on Jarrettsville Pike, entered into an agreement with the U.S. Environmental Protection Agency to clean up what was termed the "southern plume" of contamination in Jacksonville, MDE records show. Amoco, which operated another station in the area, was responsible for cleanup of a "northern plume."
Those cleanup efforts lasted from 1987 to 1994, and monitoring continued until 1996, according to MDE records.
Residents along Sunnybrook Road, southwest of Four Corners, were having a different water problem in the 1980s and 1990s. Tests in 1981 showed that their well water was contaminated by a degreasing agent that had been used at a nearby Army Nike missile site.
From 1981 until 1994, when they were connected to a new community well, Daniel and Anne Shanahan, and several other families, used bottled water for drinking and cooking. The bottles arrived each month, courtesy of the Army.
The retired couple said they feel fairly confident that their water supply is safe. But they added that they're concerned about their neighbors to the north.
"You feel like you lose control of your life," said Anne Shanahan. "My heart goes out to the people on Robcaste. They have a rough road ahead."
Last week, after news of the most recent spill spread, more than 300 residents packed Jacksonville Elementary School library to ask questions. Jodi Howe left the meeting unsatisfied.
She said an initial test of her water by a company she hired came back fine, but she wonders how long it can take for gasoline to travel through the ground.
"It looks OK now, but if we test it every month, does that mean you're drinking contaminated water for a month?" she asked.
Janice Scarff, a Sweet Air Road resident since 1970, said that her son has pleaded with her not to drink from her well.
"I don't think it will show up instantly," Scarff says. "But I think they should be checking our schools, and I think they should be checking our businesses."
Baltimore County school officials say the well water at Carroll Manor and Jacksonville elementary schools is regularly tested. Pupils and faculty at Jacksonville Elementary were already using bottled water because an elevated amount of lead was detected in the school well, said Charles A. Herndon, a school system spokesman.
Herndon said that school officials have not received test results or information from environmental officials showing that they need to be concerned about the gasoline leak.
Bessie Over, who lives north of Four Corners, said her water tests fine. But, she said, she insists on bottled water at the community's restaurants.
"I wouldn't put water in Jacksonville to my lips for any amount of money," Over said. "It's just sad."
Sun reporters Liz F. Kay and Timothy B. Wheeler contributed to this article.