Updated five times now at bottom.

This diary updates my previous entries which can be found starting here.

The Coast Guard and NOAA have not yet released an updated graphic showing spill extent. I will update this diary when such a graphic is available some time today, along with other updates as they become available. This map from the New York Times shows possible spill impact as well as wildlife areas at risk.

NOAA and BP have discovered or just now announced a third leak from the well left behind the Deepwater Horizon rig. BP is asking for help from the US military:

… A massive oil spill in the Gulf of Mexico that has become far worse than initially thought crept toward the coast Thursday as government officials offered help from the military to prevent a disaster that could destroy fragile marshlands along the shore.

An executive for BP PLC, which operated the oil rig that exploded and sank last week, said on NBC’s "Today" that the company would welcome help from the U.S. military.

"We’ll take help from anyone," said Doug Suttles, chief operating officer for BP Exploration and Production.

The Coast Guard has urged the company to formally request more resources from the Defense Department …

It is not clear that the military will respond:

… Adm. Mike Mullen, chairman of the Joint Chiefs of Staff, was briefed Thursday morning on the issue, said his spokesman, Capt. John Kirby. But Kirby said the Defense Department has received no request for help, nor is it doing any detailed planning for any mission on the oil spill …

(Poster Lbrty helpfully points out that the Tiber oilfield that Deepwater Horizon was drilling contains a bottomless several billion gallons of oil, only several millions of which have leaked. In other words, this leaking could potentially spew 1,000,000 gallons of crude oil into the Gulf of Mexico until the leak is contained and stopped, which might be months from now.)

The well contains 4.2 million gallons of oil:

… If the well cannot be closed, almost 100,000 barrels of oil, or 4.2 million gallons, could spill into the Gulf before crews can drill a relief well to alleviate the pressure. By comparison, the Exxon Valdez, the worst oil spill in U.S. history, leaked 11 million gallons into Alaska’s Prince William Sound in 1989 …

Previous reports have shown that it will take weeks to even localize the spill for easier removal, and months to plug the leak with so-called "intervenion wells", as the attempt to activate the massive cut-off valve on the well via robotic sumbarine has failed, and attempts at experimenting with burning the slick in local regions are just beginning. At a rate of 200,000 gallons per day, the well leaks will expel 1,000,000 gallons oil. In twenty days, the well will have effectively emptied into the Gulf of Mexico in a spill just under half of the total volume of the Exxon Valdez disaster.

Evidence has emerged that the new total leak rate is in excess of BP’s reported worse-case scenario response capacity. We’ve already seen that the leak rate dwarfs any ability of the Federal government to respond completely. BP may have been exempted by the Minerals Management Service from filing an emergency response plan to address "sudden blowout" conditions at the well.

The oil slick is now 16 miles from the mouth of the Mississippi river. If the slick makes shorefall there, the environmental and economic damage could be severe:

… Wind patterns may push the spill into the coast of Louisiana as soon as Friday night, officials said, prompting consideration of more urgent measures to protect coastal wildlife. Among them were using cannons to scare off birds and employing local shrimpers’ boats as makeshift oil skimmers in the shallows … Part of the oil slick was only 16 miles offshore and closing in on the Mississippi River Delta, the marshlands at the southeastern tip of Louisiana where the river empties into the ocean. Already 100,000 feet of protective booms have been laid down to protect the shoreline, with 500,000 feet more standing by, said Charlie Henry, an oil spill expert for the National Oceanic and Atmospheric Administration, at an earlier news conference on Wednesday.

More from HuffPost:

… As dawn broke Thursday in the oil industry hub of Venice, about 75 miles from New Orleans and not far from the mouth of the Mississippi River, crews loaded an orange oil boom aboard a supply boat at Bud’s Boat Launch. There, local officials expressed frustration with the pace of the government’s response and the communication they were getting from the Coast Guard and BP officials …

… "We’re not doing everything we can do," said Billy Nungesser, president of Plaquemines Parish, which straddles the Mississippi River at the tip of Louisiana.

"Give us the worst-case scenario. How far inland is this supposed to go?" Nungesser said. He has suggested enlisting the local fishing fleet to spread booms to halt the oil, which threatens some of the nation’s most fertile seafood grounds.

Louisiana has opened a special shrimp season along parts of the coast so shrimpers can harvest the profitable white shrimp before the spill has an effect.

Michael Nguyen, 58, was aboard his 82-foot shrimp boat, the Night Star III, waiting for news Thursday morning on what has happening with the slick. He wasn’t panicking, but was clearly worried.

"The oil come in everywhere, the shrimp die, the crabs die, the fish die. What do I do? Stay home a long time?"

The spill has moved steadily toward the mouth of the Mississippi River and the wetland areas east of it, home to hundreds of species of wildlife and near some rich oyster grounds.

Plaquemines Parish oysterman Mitch Jurasich said by telephone from his boat that he and other crews are working around the clock to harvest as many oysters as possible …

… "But we’re fighting a losing effort. We’ve got an extreme amont of product in the water," he said.

A federal class-action lawsuit was filed late Wednesday over the oil spill on behalf of two commercial shrimpers from Louisiana, Acy J. Cooper Jr. and Ronnie Louis Anderson.

The suit seeks at least $5 million in compensatory damages plus an unspecified amount of punitive damages against Transocean, BP, Halliburton Energy Services Inc. and Cameron International Corp.

Jim Klick, a lawyer for Cooper and Anderson, said the oil spill already is disrupting the commercial shrimping industry.

"They should be preparing themselves for the upcoming shrimp season," he said. "Now they’re very much concerned that the whole shrimp season is out."

Mike Brewer, 40, who lost his oil spill response company in the devastation of Hurricane Katrina nearly five years ago, said the area was accustomed to the occassional minor spill. But he feared the scale of the escaping oil was beyond the capacity of existing resources.

"You’re pumping out a massive amount of oil. There is no way to stop it," he said.

And, as of yet, there is still no plan announced to handle the sunken, capsized wreck of the Deepwater Horizon itself, with its 700,000 gallons of toxic diesel fuel.

This spill is now demanding further involvement from the Federal government, and is now threatening the Gulf Coast of Louisiana, home to Mary Landrieu, who has been a lobbied proponent of offshore oil drilling. The impact to the Gulf could be enormous if, as now appears possible, the entire well drains into the Gulf of Mexico over a period of a few weeks in a slow-motion replay of the Exxon Valdez disaster. As it stands now, the drilling-friendly Obama administration has orchestrated an "investigation" into the disaster driven by oil-drilling proponent Ken Salazar and administration officials Janet Napolitano and Lisa Jackson. It does not appear that there is any party to this investigation who is not a direct report to President Obama, who has made expanded offshore oil drilling the only tangible part of, perversely, his leadership on climate change legislation to date.

I’ll try to update this diary later with more information as to the response from environmentalists – which appears minimal so far – as well as the investigation, and, of course, spill status updates as they appear. This disaster has raised many questions about the prudence of the Obama administration’s emphasis on offshore oil drilling as part of climate change legislation.

Update 1:

Janet Napolitano has declared the spill to be of "national significance" indicating probably that the Federal government will mobilize national security resources, potentially even military resources, to try to respond to the spill. The spill’s outermost extent is now 12 miles from the mouth of the Mississippi river and is expected to make shorefall tomorrow.

If the Department of Defense responds, then, once again, American military personnel will be deployed to America’s Louisiana Gulf Coast.

Update 2:

The House Select Committee on Energy Independence and Global Warming is now announcing that oil industry executives will be called to Congress for some sort of testimony:

… The House Select Committee on Energy Independence and Global Warming has called the chief executives of America’s top five oil companies to testify on the growing Gulf Coast spill and the companies’ rising profits coupled with rising prices for consumers.

Committee Chairman Ed Markey (D-Mass.) blasted out a press release Thursday, reproduced below:

Markey Calls Oil CEOs to Congress

Oil Spill in Gulf, Energy Policy, Effects of Gas Prices on Economy Prompt Request for Oil Heads

WASHINGTON (April 29, 2010) – A large, growing oil slick in the Gulf of Mexico has been set on fire to contain the damage and is threatening the coastline. Oil profits are up. And the nation’s largest oil companies are finally coming to the table to discuss America’s energy policy.

With these multiple issues at play, Rep. Edward J. Markey (D-Mass.) sent formal notice to the heads of America’s top five oil companies to soon appear before the Select Committee on Energy Independence and Global Warming, which Rep. Markey chairs.

"From the health of our economy to the health of our environment, it’s time for the American public to hear from the oil companies," said Rep. Markey. "Their opinions and answers on the issues of energy policy are vital given the push in Congress to construct a comprehensive energy independence strategy for our nation."

The Gulf of Mexico oil spill, which is now leaking at a rate of 5,000 barrels of oil per day, could by next week exceed the size of the Santa Barbara oil spill of 1969. This accident follows the release of thousands of miles of coastline by the Obama administration for potential new offshore drilling …

This spill is now likely to be of historic character.

Update 3:

The awful Mary Landrieu is already trying to push back against the obvious conclusion about offshore oil drilling (we don’t want it!) in this disaster:

… Sen. Mary Landrieu, a longtime supporter of offshore oil drilling, has called for a full investigation into the incident.

But in recent days, as federal agencies launch their own investigation and other members of Congress demand answers from oil producer BP and drilling operator TransOcean, she has preached caution. Landrieu says that the incident should "not be used inappropriately" to halt President Obama’s recent push for expansion of offshore drilling.

"Both advocates and critics of offshore drilling have recognized the significance of this tragedy… we cannot stop energy production in our country because of this incident," Ms. Landrieu said.

In two previous congressional hearings, Landrieu minimized the chance of such a massive accident occurring on an offshore oil rig and also minimized the impact of any oil spill, saying it would hardly fill one-third of the reflecting pool outside of the Capitol …

That Huffington Post article has some must-read information on the way Landrieu – who is by all appearances, a paid shill for the oil industry – has been scuttling around trying to pretend to embrace an environmental ethos while really just driving to have low-regulation offshore drilling handed to her extraction industry sponsors by the Obama administration and the Congress.

If only there were lemon laws on politicians, Mary Landrieu could be "taken back" for a full refund.

Update 4:

The extraction industry is already trying to do online PR. Do a Google search on "Deepwater Horizon" and the link above is the first and only sponsored link that seems to emerge. Clearly, the oil industry is panicking.

Update 5:

The New York Daily News has led the charge in regular mass media, basing the claim on back-calculation from the updated leak rate today, that the Horizon disaster will dwarf the Exxon Valdez in impact:

… About 210,000 gallons of oil per day has been leaking since the BP rig caught fire and sank …

It was heading for Louisiana’s fragile coastal wetlands – and $3 billion seafood industry – just as the shrimping season is set to begin.

BP is drilling a "relief well" to divert the oil, but it would take three months to complete, Suttles said.

By then, the undersea gusher of crude will have topped the 1989 Exxon Valdez calamity, which destroyed Alaska’s Prince William Sound.

BP officials have claimed that the leak is "new", which would indicate that the huge flow rate reported today is recent and the spill volume total is smaller than would be the case if BP had concealed the third leak from day 1 of the disaster. Unfortunately, any "investigation" driven by the oil-friendly Obama administration will probably not determine whether or not BP has been hugely dishonest about the leak rate coming from its collapsed riser pipe in the Gulf.