Friday, July 25, 2008

Black and white twins: Brothers from the same mother

By Linda Dahlstrom

Some things aren’t always black and white. Then again, sometimes they are – like the twin sons born July 11 to a German couple.

The first baby that was born, Ryan, has light skin and blue eyes. His brother, Leo, is dark-skinned with brown eyes.

"None of us could believe it," the maternity ward's head doctor, Birgit Weber, told one news source. "Both kids have definitely the same father."

Stephan Gerth is German and white. His wife, Florence Addo-Gerth, is from Ghana and has dark skin.

It was “a real surprise,” Gerth told the German newspaper Die Welt, adding that the most important thing to him isn’t color, but that everyone is healthy.

The odds are one in a million, say doctors, but it can happen with fraternal twins due the genetic soup in our backgrounds. Peter Propping, former director of the Institute for Human Genetics at Bonn University, told Die Welt that the black mother may have had some white ancestors, or that the white father may have had black ones. Very occasionally, the roll of the DNA die may cause the baby of biracial parents to inherit only the genetic coding for one color.

Rare though they are, the German twins do have some company. In the past few years, at least three mixed race couples have welcomed twins who were also black and white.

In 1993, another set of black and white twins was born to the Dutch couple, Wilma and Willem Stuart, but it turned out to be a case of an in-vitro mix-up. The parents, who are both Caucasian, were mystified when the twins were born, but fell deeply in love with both of them. However, after about a year, genetic tests revealed that while one of the twins was biologically related to both parents, the other twin was not.

The hospital called it a “deeply regrettable mistake.” It soon became apparent that a device similar to a large eyedropper had been used twice, causing another man’s sperm to be mixed with Willem’s. The couple remembers two other couples in the waiting room the day of the procedure. One of them was black.

Being of different races and coming from different fathers hasn’t stopped the Stuart boys from closely bonding. While the dark-skinned boy did eventually meet the man who was his biological father, the brothers consider themselves full twins. In 2005, they attended a twins festival and proudly won the “Least alike twins” award.”

“For the two boys, being celebrated for their differences finally answered all the questioning looks, nasty teasing, and outright expressions of disbelief they've endured all these years,” Wilma Stuart told Dateline, which has been following the family since 1993.

Stephan Gerth and Florence Addo-Gerth, the parents of the newest set of “black and white” twins, know they’ll face some incredulous stares.

"I imagine sitting in a playground where the other mothers will call me crazy when I tell them the boys are twins," Florence told www.peacefmonline.com.

Like all siblings, their differences are more than skin deep. The twins also have distinctly different personalities, say their parents. Leo, the dark-skinned baby, is quieter; Ryan, his light-skinned brother, is temperamental. "When he's hungry, he's hard to stop,” said the mother.

She says her children were born looking exactly as they should. "God has decided that my children should have different skin colors," she says.

Friday, May 9, 2008

Myanmar Flooding Seen From Space

LiveScience Staff - LiveScience.com


The devastation wrought in Myanmar by a Tropical Cyclone Nargis is revealed in new NASA satellite images.

Nargis made landfall with sustained winds of 130 mph and gusts of 150 to 160 mph, the equivalent of a strong Category 3 or minimal Category 4 hurricane, according to Accuweather.com. The death toll could exceed 100,000, officials said.

Flooding is difficult to capture in pictures, even from satellites, particularly when the water is muddy. NASA used both visible and infrared light to make floodwaters more obvious.

The before and after views of the Myanmar coast and Irrawaddy Delta, where much of the devastation occurred, were generated by the Moderate Resolution Imaging Spectroradiometer on NASA's Terra satellite. Water is blue or nearly black, vegetation is bright green, bare ground is tan and clouds are white or light blue.

An image from April 15, 2008, shows dark blue or nearly black water that sharply outlines the shore, the Irrawaddy River (which flows south through the left-hand side of the image). The wetlands near the shore are a deep blue green. Cyclone Nargis came ashore across the Mouths of the Irrawaddy and followed the coastline northeast.

The entire coastal plain is flooded in an image taken on May 5. Here, much of Myanmar is seen as a combination of blue water and turquoise muddy runoff into the Gulf of Martaban. Previously tan areas without vegetation are flooded, such as the 4-million population city of Yangon. The cyclone's path is clearly visible as it moved northeast along the coast from the Mouths of the Irrawaddy. Light blue or white clouds float above the flooded landscape.

Man loses 28 relatives in Myanmar village hit by cyclone

Associated Press

The 68-year-old fisherman tries to explain how a cyclone swept away the rest of his family, but he can utter only a few simple words before he is overcome by tears and trauma.

"All my 28 family members have died. I am the only survivor," said Thein Myint, whose flimsy house was torn apart May 3 when Cyclone Nargis sent powerful waves surging from the sea.

Thein Myint's village is in a devastated belt around Bogalay, one of the worst-hit towns in the Irrawaddy delta some 20 miles from the Indian Ocean where thousands have died.

Other survivors — from similar extended families still common in rural Myanmar — are now fighting hunger, illness and wrenching loneliness.

"We huddled together, but the big trees carried by the waves knocked down two of my children and my wife," said Htay Maung, 70, recounting a common story at a large Buddhist monastery where many others had taken shelter from the 120 mph winds.

When the winds first sprang up, and the storm surge rose higher, he, his wife and four children climbed to the roof of their house and clung to each other.

"Only two of my children survived," Htay Maung told an Associated Press reporter who reached the town via car from the main city of Yangon, a trip of more than 100 miles that took about five hours because of flooding and downed bridges.

As Htay Maung spoke, children cried, adults moaned and others complained that authorities had only distributed sodden, fermented rice.

"We knew that the storm was coming, but we didn't know how dangerous or deadly it will be, so as usual I told the children to stay indoors," said one of the men sheltered in open-sided sheds in the large monastery compound.

"We heard of the storm warning around 1 p.m., and the cyclone came five hours later," added another.

Bogalay residents said the warning came via a public address system in the town but written notices were dispatched by boats to the surrounding villages, which suffered far more when Nargis struck.

The villages continue to face hardship, since access by aid workers is difficult and shelter almost nonexistent.

Many villagers who have not sought refuge in the badly battered town live under four or five coconut palm leaves they have tied together, surrounded by stagnant, fetid pools of water.

Soft drink cans are used to catch rain water for cooking what little rice remains. Some are trying to dry unhusked rice beside the road. Villagers tell their urgent needs: food, clothing and medicine for illnesses and injuries.

One man's naked back was red and raw from the lashings of broken branches and fallen tree trunks swirling in the a wall of water as high as 12 feet that rushed deep into the low-lying delta.

Initially, Myanmar authorities had feared that 10,000 people had perished in the Bogalay area, which Myanmar's meteorological department said was in the path of the cyclone's eye. In recent days, however, officials have given no breakdowns of the toll, saying only that at least 62,000 are dead or missing nationwide.

Bodies have been cleared from the streets of Bogalay and repairs have begun on roofless houses and damaged infrastructure. Workers haul utility poles and corrugated iron sheets for roofing as some helicopters arrive with relief supplies.

Thein Myint, the broken fisherman who lost eight children among his 28 relatives, did not seem to care about repairs and restoration, or even money.

Money "is useless to me now, without my family," he said as he ate rice mixed with boiled banana shoots. "They were washed away."

Friday, April 18, 2008

What Really Sank the Titanic?

By CARLEY PETESCH, Associated Press Writer

Book by metallurgists blames rivets for Titanic tragedy

The tragic sinking of the Titanic nearly a century ago can be blamed on low grade rivets that the ship's builders used on some parts of the ill-fated liner, two experts on metals conclude in a new book.

The company, Harland and Wolff of Belfast, Northern Ireland, needed to build the ship quickly and at reasonable cost, which may have compromised quality, said co-author Timothy Foecke. That the shipyard was building two other vessels at the same time added to the difficulty of getting the millions of rivets needed, he added.

"Under the pressure to get these ships up, they ramped up the riveters, found materials from additional suppliers, and some was not of quality," said Foecke, a metallurgist at the U.S. government's National Institute of Standards and Technology who has been studying the Titanic for a decade.

More than 1,500 people died when the Titanic, advertised as an "unsinkable" luxury liner, struck an iceberg on its maiden voyage in 1912 and went down in the North Atlantic less than three hours later.

"The company knowingly purchased weaker rivets, but I think they did it not knowing they would be purchasing something substandard enough that when they hit an iceberg their ship would sink," said co-author Jennifer Hooper McCarty, who started researching the Titanic's rivets while working on her Ph.D. at Johns Hopkins University in 1999.

The company disputes the idea that inferior rivets were at fault. The theory has been around for years, but McCarty and Foecke's book, "What Really Sank the Titanic," published last month, outlines their extensive research into the Harland and Wolff archives and surviving rivets from the Titanic.

McCarty spent two years in Britain studying the company's archives and works on the training and working conditions of shipyard workers. She and Foecke also studied engineering textbooks from the 1890s and early 1900s to learn more about shipbuilding practices and materials.

"I had the opportunity to study the metallurgy of several rivets," McCarty said. "It was a process of taking thousands of images of the inside of these rivets, finding out what the structure was like, doing chemical testing and computer modeling.

"Seeing the kind of levels we saw in different areas, in different parts of the ship led us to believe they would have ordered from different people," she said, adding this may have led to the weaker rivets.

The two metallurgists tested 48 rivets from the ship and found that slag concentrations were at 9 percent, when they should have been 2 to 3 percent. The slag is a byproduct of the smelting process.

"You need the slag but you need just a little to take up the load that's applied so the iron doesn't stretch," Foecke said. "The iron becomes weak the more slag there is because the brittleness of the slag takes over and it breaks easily."

Foecke said the main question was not whether the Titanic would sink after hitting the iceberg, but how fast the ship went down.

He believes the answer is provided by the weak rivets. His analysis showed the builders used stronger steel rivets where they expected the greatest stress and weaker iron rivets for the stern and the bow, where they thought there would be less pressure, he said. But it was the ship's bow that struck the iceberg.

"Typically you want a four bar for rivets," Foecke said, using the measurement for the strongest rivets. "Some of the orders were for three bar."

Harland and Wolff spokesman Joris Minne disputed the findings. "We always say there was nothing wrong with the Titanic when it left here," he said.

When the iceberg hit the Titanic, it scraped alongside the ship. Foecke said this affected a number of seams in the bow and the weak rivets let go, putting more pressure on the strong rivets.

"Six compartments flooded. If the rivets were on average better quality, five compartments may have flooded and the ship would have stayed afloat longer and more people would have been saved," Foecke said. "If four compartments flooded, the ship may have limped to Halifax."

The company does not have an archivist, but it refers scientific questions on the Titanic to retired Harland and Wolff naval engineer David Livingstone, who also has researched the ship's sinking.

He said he largely agrees with the authors' findings on the metallic composition of the rivets, but added their conclusions that the rivets were to blame for the sinking are "misleading and incorrect" because they do not consider the ship's overall design and the historical context.

"You can't just look at the material and say it was substandard," Livingstone said. "Of course material from 100 years ago would be inferior to material today."

He said he has found no document to support the argument that Harland and Wolff knowingly used substandard material. He pointed out that the Olympic, a ship the company built at the same time using the same materials, had a long life with no troubles. The third vessel turned out in the early 1900s was attacked and sunk in World War I.

Livingstone said he is not sure why iron rivets were used in the bow and the stern but believes it may have been because a crane-mounted hydraulic rivet machine could not reach those points. He said the iron rivets were wider to compensate for the difference in strength.

Contrary to Foecke's theory, Livingstone said, the Titanic did not go down fast compared to other ships that have sunk.

He said the Titanic did not capsize — as do most sinking ships — but maintained an even keel until the last moment, going down after about 2 1/2 hours when the weight of the water it took on became too much.

William Garzke, chairman of the forensics panel of the Society of Naval Architects and Marine Engineers based in New Jersey, said wrought iron was commonly used at that time, but steel was the newer, stronger choice.

Garzke, who also has studied the Titanic sinking, said the two scientists made a good point about the variability of the rivets, but "the problem is not the metallurgy of the rivets, it was the design of the riveted joints."

He said that the company used only two rivets at the site of impact, when three would have provided more strength and durability.

Wednesday, April 16, 2008

Do animals have personalities?

By Jane McGrath

It may seem like a silly question to pet owners. Of course animals have personalities. Just take a trip to your neighborhood dog park, and you'll see those personalities in action: The miniature pinscher marches confidently into the middle of wrestling match among a pack of large dogs, while the mixed breed Labrador tentatively sticks to her owner's pant leg.

Pet owners are quick to attach personalities to their pets. But what do scientists say about this concept? Is it possible for animals to be irritable, adventurous, neurotic or even a mixture of these characteristics?

To determine whether animals have personalities, we first have to define what a personality is, which is surprisingly difficult. Definitions of personality range from general to precise. For example, personality could merely entail any collection of traits, or might necessitate the traits be "unique," "dynamic" and "enduring" [source: Cottam]. And some psychologists question whether personality is definable at all, judging from the inconsistency of traits in people [source: OUP]. Nevertheless, scientists must know what to look for when they try to decide if an animal has one or not.

Read on to learn how scientists empirically study this concept and what research shows about the extent to which the depth and consistency of an animal's personality can rival a human's.

Animal Personality Studies

Studying personality in animals seems silly to some; indeed, scientists wishing to pursue the subject have had to overcome skepticism in the academic world [source: Dye]. Their attempts seem to be working, as the amount of research on animal personality has been steadily growing since the 1990s.

For instance, Dr. Samuel Gosling has been fighting to expand research in the area of animal personality and gained media attention for his research in dog personality. Because dogs cannot tell us about their feelings and behavior, Gosling compared how observers interpret personality in other humans and in dogs. In one test, observers unfamiliar with the people and the dogs judged them based on their behavior performing various activities. In the other test within the study, friends familiar with the people and the dogs assessed their personalities. The participants reported if they found the people and the dogs extroverted, agreeable, neurotic and open. Gosling found that these judgments were consistent for the humans and the dogs [Source: Gosling]. This and other methods have led Gosling and others to believe not only that we can study personality in animals, but that dogs do in fact have distinct personalities.

OK, so dogs probably possess personality, but what about other, less domesticated animals? After all, humans spend time with their dogs and deliberately manipulate dog breeding. Does Mother Nature allow personality to thrive in wild animals?

Scientists in the Netherlands studied a species of wild birds, called great tits, to find out. The studies incorporated both lab tests and observations of the birds in their natural habitat. Their studies found distinct and varied personalities among the species [source: Dingemanse]. Some birds showed aggressive or adventurous behavior, while others were shy and timid [source: Dingemanse]. The studies also found evidence that personality is genetically inherited [source: Dingemanse]. Controlling how the birds bred, the scientists were able to amplify certain characteristics. One scientist behind the studies reported that more than half of the differences in traits came from genetic inheritance [source: Zimmer]. Curiously, natural selection had not weeded out one personality or the other, but kept the birds significantly diverse.

Other studies have found personality traits in various other species, such as hyenas, ferrets, primates, spiders and even fish. As the research grows, the question might no longer be whether animals have personalities, but rather if there is any species that doesn't. However, skeptics question the reliability of using human personality terms on animals [source: Zimmer]. Does the idea of "shyness" mean the same thing when it's applied to a human as when it's applied to an animal?

In the end, these studies may have some practical benefits. On the next page, we'll discuss those benefits.

Implications of Animal Personality Studies

If animals have unique personalities, so what? These studies actually could have some interesting uses and implications.

For instance, Gosling hopes that his work on dogs will lead to some reliable methods for determining a dog's individual personality. If we can accurately assess a dog's personality, then people and families who are looking to buy or adopt a dog will be able to find one that matches their own tastes and temperaments. In addition, Gosling hopes perfected methods might help people predict which dogs will be best in working situations, such as search-and-rescue, detecting explosives or guiding.

Also, researchers hope the studies will shed light on human personality. Although psychologists have been studying human personality for a long time, animal personality studies have great potential to shed light on people. We can learn a lot from certain personality tests that are easier or more ethical to conduct on animals than on humans. Gosling mentions the following examples to show how animal personality research could contribute to knowledge about human personality:

  • Scientists can observe animals more extensively and longer than they can humans, so they can learn more about behavior in different situations.
  • Experimenters can inject hormones into animals, which allows them to observe the effects on behavior.
  • Testing drugs that affect neurotransmitter activity in animals can show how it alters behavior.
  • Removing and testing brain tissue in animals lets scientists measure chemical activity better.
  • Scientists can control an animal's living conditions to see how comfortable and harsh environments affect the development of personality traits.

[source: Gosling]

In addition, because research on the evolution of personality is scarce, animal research could tell us a lot about the evolution of human personality [source: Zimmer].

Prozac
Some veterinarians not only think animals have personalities, but that they can even suffer from depression or separation anxiety when they are left at home alone all day. Studies estimate that more than 10 million dogs in the U.S. suffer from separation anxiety [source: Booth].

In 2007, the FDA approved a chewable antidepressant for dogs developed by Eli Lilly, the company that makes Prozac. Reconcile, the dog friendly antidepressant, even has a beef flavor. Combined with therapy, the drug successfully treated a little more than 70 percent of depressed dogs [source: Booth].

Experts also say parrots suffer depression when they are left home alone. Romain Pizzi, a specialist in animal medicine, notes that parrots will actually harm themselves during bouts of depression and that liquid Prozac has helped to stop that behavior [source: Cleland].

"Bowlingual"

Want to get to know man's best friend better? Takara, a Japanese company, has invented a device that it claims interprets a dog's emotions. Known as the "Bowlingual," this gadget uses a microphone on the dog's collar to read his barks, growls or whimpers, and then sends a signal to a hand held console that displays what your dog is trying to say. The console shows simple phrases, such as "How boring" and "I'm arf-ully lonely. Please play with me more" [source: BBC News]. Takara developed this gadget by hiring animal behaviorists to study dog noises and translate them [source: TIME].

Friday, March 28, 2008

10 Most Astonishing Results of Global Warming

LiveScience

10. Aggravated Allergies

Have those sneeze attacks and itchy eyes that plague you every spring been worsening in recent years? If so, global warming may be partly to blame. Over the past few decades, more and more Americans have started suffering from seasonal allergies and asthma. Though lifestyle changes and pollution ultimately leave people more vulnerable to the airborne allergens they breathe in, research has shown that the higher carbon dioxide levels and warmer temperatures associated with global warming are also playing a role by prodding plants to bloom earlier and produce more pollen. With more allergens produced earlier, allergy season can last longer. Get those tissues ready.

9. Heading for the Hills

Starting in the early 1900s, we've all had to look to slightly higher ground to spot our favorite chipmunks, mice and squirrels. Researchers found that many of these animals have moved to greater elevations, possibly due to changes in their habitat caused by global warming. Similar changes to habitats are also threatening Arctic species like polar bears, as the sea ice they dwell on gradually melts away.

8. Arctic in Bloom

While melting in the Arctic might cause problems for plants and animals at lower latitudes, it's creating a downright sunny situation for Arctic biota. Arctic plants usually remain trapped in ice for most of the year. Nowadays, when the ice melts earlier in the spring, the plants seem to be eager to start growing. Research has found higher levels of the form of the photosynthesis product chlorophyll in modern soils than in ancient soils, showing a biological boom in the Arctic in recent decades.

7. Pulling the Plug

A whopping 125 lakes in the Arctic have disappeared in the past few decades, backing up the idea that global warming is working fiendishly fast nearest Earth's poles. Research into the whereabouts of the missing water points to the probability that permafrost underneath the lakes thawed out. When this normally permanently frozen ground thaws, the water in the lakes can seep through the soil, draining the lake, one researcher likened it to pulling the plug out of the bathtub. When the lakes disappear, the ecosystems they support also lose their home.

6. The Big Thaw

Not only is the planet's rising temperature melting massive glaciers, but it also seems to be thawing out the layer of permanently frozen soil below the ground's surface. This thawing causes the ground to shrink and occurs unevenly, so it could lead to sink holes and damage to structures such as railroad tracks, highways and houses. The destabilizing effects of melting permafrost at high altitudes, for example on mountains, could even cause rockslides and mudslides. Recent discoveries reveal the possibility of long-dormant diseases like smallpox could re-emerge as the ancient dead, their corpses thawing along with the tundra, get discovered by modern man.

5. Survival of the Fittest

As global warming brings an earlier start to spring, the early bird might not just get the worm. It might also get its genes passed on to the next generation. Because plants bloom earlier in the year, animals that wait until their usual time to migrate might miss out on all the food. Those who can reset their internal clocks and set out earlier stand a better chance at having offspring that survive and thus pass on their genetic information, thereby ultimately changing the genetic profile of their entire population.

4. Speedier Satellites

A primary cause of a warmer planet'scarbon dioxide emissions is having effects that reach into space with a bizarre twist. Air in the atmosphere's outermost layer is very thin, but air molecules still create drag that slows down satellites, requiring engineers to periodically boost them back into their proper orbits. But the amount of carbon dioxide up there is increasing. And while carbon dioxide molecules in the lower atmosphere release energy as heat when they collide, thereby warming the air, the sparser molecules in the upper atmosphere collide less frequently and tend to radiate their energy away, cooling the air around them. With more carbon dioxide up there, more cooling occurs, causing the air to settle. So the atmosphere is less dense and creates less drag.

3. Rebounding Mountains

Though the average hiker wouldn't notice, the Alps and other mountain ranges have experienced a gradual growth spurt over the past century or so thanks to the melting of the glaciers atop them. For thousands of years, the weight of these glaciers has pushed against the Earth's surface, causing it to depress. As the glaciers melt, this weight is lifting, and the surface slowly is springing back. Because global warming speeds up the melting of these glaciers, the mountains are rebounding faster.

2. Ruined Ruins

All over the globe, temples, ancient settlements and other artifacts stand as monuments to civilizations past that until now have withstood the tests of time. But the immediate effects of global warming may finally do them in. Rising seas and more extreme weather have the potential to damage irreplaceable sites. Floods attributed to global warming have already damaged a 600-year-old site, Sukhothai, which was once the capital of a Thai kingdom.

1. Forest Fire Frenzy

While it's melting glaciers and creating more intense hurricanes, global warming also seems to be heating up forest fires in the United States. In western states over the past few decades, more wildfires have blazed across the countryside, burning more area for longer periods of time. Scientists have correlated the rampant blazes with warmer temperatures and earlier snowmelt. When spring arrives early and triggers an earlier snow-melt, forest areas become drier and stay so for longer, increasing the chance that they might ignite.

Friday, February 15, 2008

Avalanche of water threatens Colorado town


By P. SOLOMON BANDA, Associated Press Writer

More than 1 billion gallons of contaminated water — enough to fill 1,500 Olympic-sized swimming pools — is trapped in a tunnel in the mountains above the historic town of Leadville and threatening to blow.

Lake County Commissioners have declared a local state of emergency for fear that this winter's above-average snowpack will melt and cause a catastrophic tidal wave.

The water is backed up in abandoned mine shafts and a 2.1-mile drainage tunnel that is partially collapsed, creating the pooling of water contaminated with heavy metals.

County officials have been nervously monitoring the rising water pressure inside the mine shafts for about two years. An explosion could inundate Leadville and contaminate the Arkansas River.

"It could come out, we just don't know where," county Commissioner Carl Schaefer said. "We're seeing changes and we're very concerned. We're not crying `Chicken Little' here."

State and federal officials agreed Thursday to conduct a risk assessment before taking any action. Critics said something should be done immediately to ease the pressure.

Peter Soeth, a spokesman for the Bureau of Reclamation, which acquired the drainage tunnel in 1959, said there was no immediate threat to Leadville's 2,700 residents.

Officials point out that a speaker system to broadcast evacuation notices has already been installed near a mobile home park that has 300 residents near the tunnel's portal.

The tunnel normally drains water that seeps into some of the hundreds of abandoned mine shafts and other mine workings in the mountains east and south of Leadville and deposits it into the East Fork of the Arkansas River about a mile north of town.

The Environmental Protection Agency raised concerns about the situation in letters sent to the Bureau of Reclamation, which has been assessing the concerns.

"Due to the unknown condition of the tunnel blockage and the large volume of water behind the blockages, we are concerned that an uncontrolled, potentially-catastrophic release of water to the Arkansas River from (the tunnel) is likely at some point," said one EPA letter sent in November.

Stan Christensen, an EPA expert on the tunnel, said the likelihood that something catastrophic can happen increases the longer nothing is done.

A water treatment plant at the foot of the tunnel removes toxins and heavy metals such as zinc, cadmium and manganese before discharging the water into the Arkansas River. The mobile home park is near the treatment plant.

New springs and seepages have appeared at California Gulch, which sits below the plant. Tests have shown high levels of heavy metals typically found in mine discharge, leading officials to conclude the trapped water is finding ways out.

"No one can tell us what it means," said Jeffrey Foley, Lake County's emergency management director. "It's finding fault lines and it's pouring mine-contaminated water into the Arkansas."

The EPA's Christensen said the water table is rising regionwide and that his agency can't immediately reach the same conclusion.

Leadville, which sits at 10,200 feet of elevation and some 100 miles west of Denver, rose to national prominence and attracted thousands of people after a gold rush in 1859. After the gold ran out, silver became the dominant mining industry.

Later, a mine that sits beneath 13,000-foot mountain peaks began shipping molybdenum ore in 1915. Miners have recovered 946,000 tons of molybdenum, used to harden steel, worth about $4 billion. The Climax mine closed in 1995.