As the EPA and BP fight over the Gulf oil spill cleanup, the Daily Beast crunches the numbers and ranks the most contaminated sites in the nation.

The BP oil rig explosion has led to untold millions in lost income for people who make their living from the Gulf, but toxic hazards are an everyday occurrence: The EPA estimates that there are 3,500 chemical spills each year, requiring $260 million to clean.

Above those, however, are the Superfund sites—places that have sustained major, long-term damage, necessitating years of cleanup. Established in 1980 after a series of toxic disasters, including the infamous Love Canal district of Niagara Falls, which turned the neighborhood into a virtual ghost town, Superfund has largely succeeded in centralizing hazardous waste cleanup and holding responsible parties financially accountable.

The BP fiasco—both a natural and human disaster—got us thinking: what are today’s most polluted toxic dumping grounds? To figure it out, we examined all available Superfund data from the Environmental Protection Agency. We filtered the results, focusing on sites that remain dangerous for human exposure and sites that have dangerous ground water. And then we ranked them using the following criteria:

· Toxicity per acre: The number of instances of each toxin, multiplied by the severity of each toxin, according to the Agency for Toxic Substances & Disease Registry, and divided by the acreage of the site.

· Toxicity per population: To determine potential human exposure we took the number of instances of each toxin, multiplied by the severity of each toxin, and divided by the population within one mile of the site. (The EPA gives a population range, and we used the higher number for this calculation.)

Since toxicity per acre is a more concrete statistic than potential human exposure (one can live near a toxic site and avoid contact), we weighted the former three times the impact of the latter. An important note: The human exposure element does not measure exposure levels, but rather indicates that the EPA believes there is a reasonable expectation that people may be exposed to contamination—exactly what the Superfund teams spend their time trying to alleviate.

#1, Milford, New Hampshire: Fletcher's Paint Works and Storage

Acres: 2 Population: 10,000 Toxic chemicals: 34

History: From 1949 to 1991 Fletcher's Paint Works operated a retail store and storage facility in this small New Hampshire town along the Souhegan River. In 1982 New Hampshire officials found leaking and open drums of paint chemicals in the storage area. Soil and groundwater around the site was later found contaminated with arsenic, lead, PCBs, and a slew of other nasty chemicals. The nearby Keyes Municipal Water Supply Well was shut down in the early 1980s after it was found contaminated by volatile organic compounds—gases emitted from paint and other household supplies. Cleanup began in 1988 and continues today. The EPA has tested homes in the area for gases seeping from soil into basements, with no health risks found in the homes and another round of testing due for June 2010. The main concern now is that fish in the Souhegan contain PCBs, and that the EPA has found evidence of people fishing in the river.

#2, Haverford, Pennsylvania: Havertown PCP

Acres: 15 Population: 50,000 Toxic chemicals: 59

History: Getting rid of toxic waste used to be so simple. National Wood Preservers, which treated wood on the site from 1947 to 1963, would take their liquid waste lined with pentachlorophenols (PCPs) to a well, and dump it down. Or they would toss the PCP-laden liquid onto the ground. A nearby stream was contaminated, though residents living within a mile of the site don't use it for drinking water. In 1992 the EPA removed 97,000 tons of liquid waste, and 60 tons of sludge from the site. The EPA is armed with $4.2 million from the Recovery Act to finish the final cleanup phase, which includes removing contaminated soil from residential property and public spaces.

#3, St. Maries, Idaho St. Maries Creosote

Acres: 5 Population: 5,000 Toxic chemicals: 19

History: Around Christmastime 1998, consultants visiting the site noticed something strange on the St. Joe River—the water appeared oily, shiny—and soil on the riverbank was severely stained. Bull trout use the river for migration, and the water has been used for drinking water, irrigation, and livestock water. The slick turned out to be creosote, a flammable compound concocted from wood tar, which was used for 26 years on the site to treat wood poles. The EPA removed 200 tons of creosote-contaminated soil from the site in February 1999. Turns out that for decades wood transferred from treatment vats to railcars was dripping with creosote. The lesson? Chemicals that spill onto the ground can migrate to water and food sources. After years of public meetings and bureaucratic evaluations, the government and the responsible private companies signed a final cleanup plan, expected to take four years, in February 2010.

#4, Walpole, Massachusetts: Blackburn and Union Privileges

Acres: 30 Population: 10,000 Toxic chemicals: 25

History: This site with the strange name has a history of hide tanning, textile and hardware production dating to the 17th century. Asbestos brake lining was produced here starting in 1915, and a fabric manufacturer took over in 1937. Two nearby lagoons were used for wastewater disposal for these two companies. "Residents at a residential lot near the site are reasonably anticipated to be exposed to lead and asbestos in soil," according to the EPA. The name comes from 17th-century water privileges, The Blackburn Privilege and The Union Factory Privilege.

#5, Whittier, California: Omega Chemical Corporation

Acres: 1 Population: 50,000 Toxic chemicals: 6

History: Tests near this site, about 10 miles southeast of Los Angeles, found the groundwater was contaminated with tetrachloroethene—a liquid usually used for dry cleaning and a likely carcinogen—at 42,000 times standards for drinking water. The closest drinking water well is just over a mile from the site, with 35 wells within four miles providing water for more than 280,000 people. The culprit is the Omega Chemical Corporation, a refrigerator recycling company that didn't do its job up to snuff. The drinking water problem for Santa Fe Springs was cleaned up after 2,700 drums of waste and contaminated soil were removed. Now the EPA is concerned about potentially toxic vapors, which have been detected near the site at levels that could produce health risks at long-term exposure indoors.

#6, Newport, Delaware: Koppers Co.

Acres: 317 Population: 10,000 Toxic chemicals: 70

History: Another creosote victim. For three decades up to 1971 the Koppers Co.—now Beazer East—used creosote and PCPs to treat telephone poles. Ponds, wetlands, groundwater and soil in and around the site were contaminated through the years with chemicals found in creosote. The site has been abandoned—trespassers are now the main concern for human contact.

#7, Bloomington, Indiana: Neal's Landfill

Acres: 18 Population: 1,000 Toxic chemicals: 1

History: For eight years in the 1960s the Westinghouse Electrical Corporation—later merged with CBS—dumped electrical equipment filled with PCBs at this site. The PCBs spread to groundwater, and although few people live in the area, those that do get their water from wells. Finally in April 1999 cleanup began, with CBS hauling away 41,748 tons of land contaminated with PCBs. Polychlorinated biphenyls are synthetic chemicals typically used for cooling or lubricating that have been linked to liver, thyroid and immune diseases. Unlike regular waste, equipment with PCBs require special recycling.

#8, Hereford Township, Pennsylvania: Crossley Farm

Acres: 209 Population: 1,000 Toxic chemicals: 16

History: For a decade until the mid-1970s Bally Case and Cooler, a manufacturing company, dumped drums of waste containing trichloroethylene (TCE) and tetrachloroethylene (PCE) about 50 miles north of Philadelphia. The Pennsylvania Emergency Management Agency was dispatched to provide bottled water in 1983 after drinking wells were found contaminated with the potentially toxic chemicals. One hundred wells in the area are tested every two years and 53 homes had carbon-filtering systems installed by the EPA in 1997. Homeowners still deal with TCE vapor, with an initial study finding two homes containing vapor. A second study is expected to find more instances of vapor at higher than acceptable levels.

#9, Bloomington, Indiana: Bennett Stone Quarry

Acres: 4 Population: 5,000 Toxic chemicals: 1

History: "This is a rural community and we believe the fish are being consumed," according to the EPA. Not good for residents near Stout's Creek, which is contaminated with PCBs. Once a limestone quarry, the site became a dumping ground in the 1960s and 1970s, particularly for electrical capacitors containing PCBs—found to have come again from Westinghouse, which ran a factory in Bloomington. Despite cleanup efforts, groundwater springs contaminated with PCBs still flow into Stout's Creek.

#10, Camden, New Jersey: Martin Aaron, Inc.

Acres: 2.5 Population: 50,000 Toxic chemicals: 3

History: For three decades Martin Aaron and other companies used this site to recycle drums of industrial waste. Steel drums were cleaned and prepared for re-use, but over the years numerous EPA violations cropped up, including overpacked drums. Other drums were buried, and discharge was illegally released. Soil on the site, in the middle of an industrial-residential area, is contaminated with arsenic, cadmium, and lead.

#11, Wellpinit, Washington: Midnite Mine

Acres: 320 Population: 100 Toxic chemicals: 18

History: The Dawn Mining Company operated the Midnite Mine on the Spokane Indian Reservation from 1955 to 1981. Uranium was extracted for profit, but tons of waste rock was left behind. The mine site itself has the highest concentration of contaminants, including metals and radionuclides, but the tribe still uses the surrounding area for hunting and recreation, with fish and surface water potentially affected by acid.

#12, Bloomington, Indiana: Lemon Lane Landfill

Acres: 10 Population: 5,000 Toxic chemicals: 1

History: The bucolic-sounding Lemon Lane in this classic college town is the last in a trio of Westinghouse PCB dump sites in Bloomington—more than 80,000 tons of PCB have been excavated from this dump. A 25-home community is just a quarter mile from the site, and within a mile 90 homes get drinking water from wells, several which have PCB contamination. As with the other Westinghouse sites, cleanup has been slow—the EPA enacted an emergency water cleanup plan in 2000, and an official water cleanup plan didn't happen until 2006. CBS has agreed to reimburse the EPA for cleanup at Lemon Lane, the Bennett Stone Quarry, and Neal's Landfill.

#13, Torrance, California: Montrose Chemical Corporation

Acres: 13 Population: 50,000 Toxic chemicals: 3

History: The 1.5 miles of coastline in Torrance, just outside of L.A., is endangered by sediment polluted with DDT from wastewater discharged by the Montrose Chemical Corporation, a DDT-manufacturing plant that operated in the area from 1947 to 1983. The EPA estimates that more than 1,700 tons of DDT were released over the course of 20 years and discharged into the Pacific Ocean. When the plant stopped operating in 1982, the plant was taken apart and removed from the area. Three years later, the property was covered in asphalt to prevent the DDT in the soil from being carried by the wind. The EPA continues to investigate the level of contamination in the area that remains in the water, storm drainage systems, sewers, air and soil.

#14, Liberty, Texas: Petro-Chemical Systems

Acres: 500 Population: 1,000 Toxic chemicals: 8

History: In 1971, Texas officials gave Liberty Trash Service permission to dump waste, including oil and chemical sludge, on the site, outside of Houston, where the Petro-Chemical Superfund now stands. The permit was revoked three years later, but drinking water and soil was contaminated by toxic chemicals, and oil used to pave a dirt road near the site was also contaminated. The land was developed for homes in 1974, but residents were relocated while the area was excavated and rebuilt in 1988. Cleanup of the soil and groundwater protection has decreased the risk of toxic exposure, but plans for the remaining pollution are still being designed.

#15, Waukegan, Illinois: Outboard Marine Corporation

Acres: 80 Population: 50,000 Toxic chemicals: 3

History: Located on a Lake Michigan harbor built in the 1800s as a haven for boats caught in storms, the Outboard Marine Corporation site is contaminated due to more than two decades of PCB leakage through floor drains directly into the harbor. A series of manufacturing plants on the site starting in the early 1900s contributed to arsenic and ammonia in the soil. The site was eventually declared a Superfund site in 1983. Waukegan bought one portion of the site in 2001 when OMC declared bankruptcy, and it has plans to build condominiums once the clean up is completed, which should be helped by an $18.5 million influx of taxpayer cash from the Recovery Act. A community advisory panel meets once a month to discuss developments.

#16, Leadville, Colorado: California Gulch

Acres: 11,520 Population: 10,000 Toxic chemicals: 15

History: The aptly named Leadville became a boomtown in the Gold Rush of the 1860s as one of the premier locations of precious metals. In the following decades, its wealth—and ultimately its environmental condition—was tied to the mining industry. Waste from metals mined in the area meant arsenic and lead contaminated the land and seeped into the groundwater. According to the EPA, which put the site on the National Priorities List in 1983, cleanup is nearly complete. Old railroad tracks have been converted into a paved trail.

#17, Tacoma, Washington: Commencement Bay

Acres: 7,680 Population: 50,000 Toxic chemicals: 23

History: On the southern part of the Puget Sound, Commencement Bay has been an industrial hub since the late 1800s. The ASARCO company smelting facility, which operated from 1890 to 1985, pumped an estimated 15 million tons of toxic byproducts onto the property. Arsenic, copper, lead and PCBs were found in the soil, sediment and water. The bay is still home to more than 300 businesses, including shipping docks, oil refineries, chemical manufacturing plants and food processing companies, but most areas are being restored or assessed.

#18, St. Louis, Michigan: Velsicol Chemical Corporation

Acres: 100 Population: 5,000 Toxic chemicals: 2

History: Velsicol, formerly the Michigan Chemical Company, manufactured a range of chemicals for nearly 40 years before the plant closed in 1978. After decades of poor disposal, the Pine River and area surrounding the plant were contaminated with toxins. Michigan Chemical agreed to pay a $38.5 million settlement to clean up and contain the pollution, as well as to avoid being sued by the state of Michigan or the EPA.

#19, Tacoma, Washington: Commencement Bay, South Tacoma Channel

Acres: 1,600 Population: 50,000 Toxic chemicals: 32

History: The South Tacoma section of Commencement Bay, spanning 2.5 square miles, contains the municipal landfill, a contaminated city well and a field which was once used for railroad manufacturing. The soil in these three areas is contaminated with metals, lead, arsenic and copper from drums leaking waste, contaminated groundwater and industrial discharge. Since 1981, cleanup in the area has progressed with groundwater treatment, soil extraction, and landfill management efforts.

#20, Edgewood, Maryland: Aberdeen Proving Ground

Acres: 13,000 Population: 50,000 Toxic chemicals: 84

History: Aberdeen Proving Ground is the Army's oldest active proving ground (a site where weapons are tested), created in 1917 six months after the U.S. entered World War I. The Edgewood area of the site was the location of chemical research, storage and disposal, and water and soil in the area contain metals and organic toxic chemicals, and undetonated explosives remain buried throughout the site. Since Aberdeen was added as a Superfund in 1990, a leaking underground storage tank has been removed, soil has been excavated, and some contaminated groundwater has been contained.

#21, Helena, Montana: Upper Tenmile Creek

Acres: 33,920 Population: 100 Toxic chemicals: 9

History: Gold, lead, copper and zinc mining from 1870 through the 1950s led to heavy metal waste runoff that has contaminated the Tenmile creek, its tributaries and sediment. An alternate water supply for the community was designated and, over the last 10 years, hundreds of thousands of cubic yards of mining waste has been removed from the site by the EPA.

#22, Marina, California: Fort Ord

Acres: 27,827 Population: 50,000 Toxic chemicals: 54

History: Near Monterey Bay, California, Fort Ord was a training ground and basic training camp for military troops for nearly 80 years prior to its formal closure in 1994. Contaminated groundwater was detected in 1990, as well as storage tanks leaking petroleum, automotive chemical containers and a 150-acre landfill containing chemical spillage. Much of the compound has ammunition and explosives, such as rockets, hand grenades and land mines, that remain undetonated. Since 1995, nearly 5 billion gallons of groundwater has been treated and a series of managed wildfires has occurred to clear plants so that the explosives can be removed.

#23, Rockford, Illinois: Southeast Rockford Ground Water

Acres: 6,400 Population: 50,000 Toxic chemicals: 38

History: Wells in Rockford were found contaminated with organic toxins, usually used in dry cleaning and machinery degreasing processes, in 1981. Residents' water supply was rerouted from private and residential wells to the city's water supply and the primary areas of contamination were identified. The EPA has spent millions of dollars to study, control and clean up the contamination, and more than 170 commercial companies in the area committed $6 million in 1998 to clean one of the most concentrated areas of contamination.

#24, Joplin, Missouri: Oronogo-Duenweg Mining Belt

Acres: 6,400 Population: 10,000 Toxic chemicals: 4

History: One of a few Superfund sites located in the tri-state mining district which encompassed parts of Missouri, Kansas and Oklahoma, the Oronogo-Duenweg area is spotted with mine shafts, waste piles and abandoned underground mines. Water in the area was found laced with lead.

#25, Smelterville, Idaho: Bunker Hill

Acres: 973,440 Population: 5,000 Toxic chemicals: 16

History: The federal government settled with ASARCO for $1.7 billion last December in the largest cash recovery in the history of the EPA. Of that, $494 million was allocated to clean the Bunker Hill site in Idaho. The area was listed as a Superfund site in 1983 and is one of the "largest and most complex" in the country according to the EPA, as contamination has affected more than 150 miles of the nearby Coeur d'Alene River and tributaries and has caused aquatic life to disappear. Like many other Superfund sites, the contamination was caused by decades of mining, milling and smelting in the area, as well as railroad operations. Studies in the 1970s revealed that three-quarters of children living in the area had unhealthy levels of lead in their bloodstream.

#26, Galena, Kansas: Cherokee County

Acres: 73,600 Population: 50,000 Toxic chemicals: 13

History: As part of the Tri-State Mining District, along with parts of Missouri and Oklahoma, Cherokee County, Kansas was the site of extensive lead and zinc mining in the late 19th century. Hundreds of mines were thriving in the early 1900s, but activity slowed by the 1930s. Though much of the toxic byproduct from decades of mining and smelting in the area has been removed, and water treatment and soil removal has been completed, the ground and surface water still contain traces of cadmium, lead and zinc.

#27, Idaho Springs, Colorado Central City, Clear Creek

Acres: 256,000 Population: 50,000 Toxic chemicals: 12

History: About 30 miles west of Denver, this site in Idaho Springs has been contaminated from runoff and waste piles from metal mines draining into Clear Creek. The Colorado area became a leading mining site in the 1800s when gold was discovered, and the mining industry continued to support the area until 1950. The site became a Superfund in 1983 and since then some of the largest sources of contamination to the creek have been identified. In 1998, a treatment facility was built to prevent water from the Argo Tunnel from entering the creek directly, preventing nearly 1,200 pounds of metals from ending up in the water each day. More than a dozen waste piles have been removed and homes affected by contaminated well water have been receiving bottled water.

#28, Odenton, Maryland: Fort George G. Meade

Acres: 13,500 Population: 5,000 Toxic chemicals: 1

History: Fort Meade, named for Union Civil War General George Meade, has been a military site since 1917. It's now known as the home of the National Security Agency. Improper disposal and storage of several chemicals, especially in a waste dump and laundry area, led to the area’s Superfund status in 1998. Since then, the Army has removed contaminated soil and storage containers, completed a river sweep and launched environmental studies throughout the area.

Reporting and research by Clark Merrefield and Lauren Streib.