ongoing major environmental disasters

back of napkin figures is almost 2 billion gallons of water.

Oregon.

Fukushima radiation has reached U.S. shores
http://www.statesmanjournal.com/story/tech/science/environment/2016/12/07/fukushima-radiation-has-reached-us-shores/95045692/

SNIP For the first time, seaborne radiation from Japan’s Fukushima nuclear disaster has been detected on the West Coast of the United States.

Cesium-134, the so-called fingerprint of Fukushima, was measured in seawater samples taken from Tillamook Bay and Gold Beach in Oregon, researchers from the Woods Hole Oceanographic Institution are reporting.

Because of its short half-life, cesium-134 can only have come from Fukushima.

Also for the first time, cesium-134 has been detected in a Canadian salmon, the Fukushima InFORM project, led by University of Victoria chemical oceanographer Jay Cullen, is reporting.

In both cases, levels are extremely low, the researchers said, and don’t pose a danger to humans or the environment.

Massive amounts of contaminated water were released from the crippled nuclear plant following a 9.0 magnitude earthquake and tsunami in March 2011. More radiation was released to the air, then fell to the sea.

Woods Hole chemical oceanographer Ken Buesseler runs a crowd-funded, citizen science seawater sampling project that has tracked the radiation plume as it slowly makes its way across the Pacific Ocean. SNIP

"well, a pint's a pound the world around..."

One hopes the release is slow enough the minimize the damage. Releasing it quickly will make sea life around Japan inedible for a very long time.

I'm just grateful it's not being sold to a nuclear power for building bombs.

The amount of water is irrelevant.

The relevant figure is the amount and type of radioactive element involved... and the reason you won't see that reported is that it violates the FUD principal. It's a naturally-occurring material (tritium) that is an incredibly weak radiator that poses essentially zero risk. In fact, many reactors sell the stuff for consumer and commercial use.

(770,000 tons x 2,000 lbs per ton) / 8.34 lbs per gallon = 184,652,278.177 gallons or about 0.185 billion gallons.

Often when hearing about large volumes of water, they speak of how many 'Olympic swimming pools' it is. google tells me an Olympic swimming pool (OSP) is 660,000 gallons.

So the 770000 tons is 184,652,278 gallons / 660,000 gallons per OSP = 279.8 Olympic Swimming Pools

and spread their radioactive material off to beaches of other countries? What am I missing here? The world was outraged about the spread or radioactive waste from Chernobyl, is the failed reactor in Japan less of a danger?

Japanese Nuclear Regulation Authority (NRA), Shunichi Tanaka, has claimed that tritium is of little danger to humans and supports TEPCO's plans to dump the water into the ocean.

I swear this is one the great scandals of our lifetime. My wife's family is convinced the Japanese government is covering up the extent of radiation exposure.

they forgot to take into account bio-accumulation, as discussed, for example, in this study:

http://www.sciencedirect.com/science/article/pii/S0265931X12001890

Bioaccumulation of tritiated water in phytoplankton and trophic transfer of organically bound tritium to the blue mussel, Mytilus edulis
. Benedict C.Jaeschke; ClareBradshaw
https://doi.org/10.1016/j.jenvrad.2012.07.008

Abstract

SNIP Large releases of tritium are currently permitted in coastal areas due to assumptions that it rapidly disperses in the water and has a low toxicity due to its low energy emissions. This paper presents a laboratory experiment developed to identify previously untested scenarios where tritium may concentrate or transfer in biota relevant to Baltic coastal communities. Phytoplankton populations of Dunaliella tertiolecta and Nodularia spumigena were exposed at different growth-stages, to tritiated water (HTO; 10 MBq l?1). Tritiated D. tertiolecta was then fed to mussels, Mytilus edulis, regularly over a period of three weeks. Activity concentrations of phytoplankton and various tissues from the mussel were determined.

Both phytoplankton species transformed HTO into organically-bound tritium (OBT) in their tissues. D. tertiolecta accumulated significantly more tritium when allowed to grow exponentially in HTO than if it had already reached the stationary growth phase; both treatments accumulated significantly more than the corresponding treatments of N. spumigena. No effect of growth phase on bioaccumulation of tritium was detectable in N. spumigena following exposure. After mussels were given 3 feeds of tritiated D. tertiolecta, significant levels of tritium were detected in the tissues. Incorporation into most mussel tissues appeared to follow a linear relationship with number of tritiated phytoplankton feeds with no equilibrium, highlighting the potential for biomagnification. SNIP

When will we start seeing this bioaccumulation?

Commercial fishing resumed off Fukushima some time back and it's quite uncommon to find any fish with detectable levels of radiation from the event.