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Ribbon
of wastewater, river runoff near Keys
BY CURTIS MORGAN
cmorgan@herald.com
For
two weeks, a barge has been dumping millions of gallons of wastewater
from a bankrupt fertilizer plant into the middle of the Gulf of Mexico.
Now,
looping currents have drawn water from the dump zone, along with a huge
plume of runoff from the Mississippi River, toward the Keys and into the
Florida Straits. Satellite tracking showed traces of the stream off
Marathon on Friday and it likely will continue to flow up along the East
Coast.
Scientists monitoring the state's ocean dumping plan don't expect
significant effects, but the nutrient-laced stream brings with it
considerable uncertainty and the unsettling specter of fish-killing red
tides and the ''black water'' algae bloom that devastated sensitive
corals, sponges and seagrasses in the Keys last year.
''We
don't really know what the impact will be,'' said Mitchell Roffer, a
Miami-based biological oceanographer hired to monitor the dumping for
the fishing industry. ``This is really one big experiment.''
There
is little to worry about, the Florida Department of Environmental
Protection insists.
The
agency concocted the controversial and expensive ( about $120 million)
scheme to dispose of about 500 million gallons of highly acidic water
brimming in pits perilously close to fragile Tampa Bay.
EMERGENCY
The
dumping is an emergency measure to reduce the risk of what even critics
agree is a truly scarier potential environmental disaster: the threat of
that untreated wastewater spilling from the Piney Point phosphate plant
in Palmetto, just a mile from Bishop Harbor in southern Tampa Bay.
Small
spills of that stuff have caused huge fish kills and plant loss in the
past. Heavy rains had filled the pits to the point where a tropical
storm or hurricane might rupture the earthen dikes, the DEP said. Last
year, the agency started dumping about 2 million gallons a day in the
harbor, but brown algae quickly bloomed.
So
the DEP decided on dumping it at sea and in April, the U.S.
Environmental Protection Agency issued an emergency permit.
The
dump zone is huge, 19,500 square miles in water depths starting at 650,
and at least 120 miles from the Gulf Coast.
The
water, while high in ammonia and nitrogen, is highly treated to meet
federal standards and remove most of the nastiest stuff such as radium,
heavy metals and a soup of chemicals. Each barge load of 7.5 million
gallons is slowly sprayed out to be almost instantly diluted by the
ocean.
CURRENT HELPS
If
anything, the appearance of a powerful loop current around the dump zone
should help reduce the potential impact from the dumping, which is
expected to last until November, said Charles Kovach, DEP's chief
scientist for the disposal project.
''It's actually helping to disperse it over a large area in a quicker
time than would be happening in the absence of it,'' he said.
But
the five-month dumping project also could add tons of pollutants to a
Gulf ecosystem already plagued by outbreaks of red tide and Florida Bay
grass beds and Keys reefs hit by last year's black water phenomena.
Scientists believe such algae blooms are triggered in large part by high
levels of nutrients such as nitrogen.
And
now, as the wastewater mingled with Mississippi River runoff flows
toward the Keys, scientists are waiting to see if anyone notices
anything amiss.
So is
the fishing industry, with some anxiety.
''It's just like with the black water event,'' said Gregory DiDomenico,
executive director of Monroe County Commercial Fishermen Inc. ``I've
told our fishermen to be on the lookout for anything strange, any odd
water quality changes or fish kills.''
So
far, there have been no reports of anything curious from the field.
However, a number of scientists are awaiting water sampling results and
other tracking data and scrutinizing satellite images showing a thick
ribbon rich with chlorophyll, an indicator of algae.
Chuanmin Hu, a research assistant professor at the University of South
Florida's College of Marine Sciences in St. Peterburg, said it's
difficult to measure the impacts after just two weeks because the loop
current has sucked Mississippi River water into the dump zone. That
river water, which forms most of the mass seen in satellites, also could
be rich in nutrients or clouded with organic material like rotting
leaves.
So
far at least, the algae levels don't look alarming, he said -- ``far
less than the level that could kill anything.''
The
DEP's Kovach also saw nothing alarming in the satellite data. He said
the stream remains far from coastal waters where red tide outbreaks
typically begin.
''Certainly if this river bloom was not there and I saw a signal like
this, I'd have more concerns than I have now,'' he said.
NOT
NEAR ANGLERS
Much
of the stream is too far out for most recreational anglers to run
across, said Roffer, president of Roffer's Ocean Fishing Forecasting
Service, a Miami company that provides reports about currents and
temperatures to commercial and tournament anglers.
However, some boats hunting for dolphin off the Keys might detect
greenish water, Roffer said. But he's not sure what to expect.
Common sense says adding nutrients to an system already struggling with
algae blooms won't help, but other environmental impacts from the Gulf
''outweigh anything they're doing,'' said Brian Keller, science
coordinator for the Florida Keys National Marine Sanctuary.
DEP
estimates bolster that view. Overall, the state estimates it will add 40
tons of nitrogen to the Gulf -- less than one-hundredth of 1 percent of
what comes out of the Mississippi in a year. And the daily impact of 250
pounds of nitrogen-ammonia is less than a tenth of what comes from the
septic tanks, cesspits and other waste systems of the Keys.
Even
critics concede the dumping is the lesser of evils -- at least compared
with the potential destruction in shallow and sensitive Tampa Bay.
''The
devastation of untreated water in the bay would be staggering,'' said
Doug Metko, a fishing captain and board member of the Florida Guides
Association.
The
DEP agreed to push the dumping zone from 40 to 120 miles -- not as far
as some commercial fishermen wanted -- but that eased the concerns of
many.
With
promises of close state and federal monitoring, Metko said, ``I'm not
panicked about this thing.''
But
others say the dumping never would have been necessary if the state had
acted quicker to close the struggling Piney Point phosphate plant.
The
facility went bankrupt in 2001, and the state was stuck with a
staggering cleanup, said David White, director of The Ocean Conservancy.
''DEP
tries to dismiss a lot of the concerns by saying it's all going to be
diluted'' he said. ``That confuses concentration with loads. They're
just adding fuel to the fire and they can't say what the long-term
effects will be.''
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