With a rubber glove on one hand, volunteer Steve Bott guarded three bins.
As delegates and visiting dignitaries approached with food scraps, plastic containers and refuse that normally passes as trash, he blocked, parried and occasionally went digging to keep things out of the one bin marked "landfill."
"That's for the compost!" he half-shouted at one surprised-looking woman in the crucial moment before she dropped her cup, made of biodegradable, corn-based plastic, into the landfill bin.
She redirected her toss. Crisis averted.
Making Denver's Democratic National Convention Earth-friendly was a noble, notable, yet often implausible goal during the four-day convention that brought tens of thousands of extra people to Denver last week. Spending his evenings in the Pepsi Center's concourse as Democratic big-wigs spoke inside, Bott explained he was excited to be among hundreds of "green" volunteers focused on composting, recycling and saving space in the region's landfills.
"It feels like I'm doing a good deed," he said.
But to accomplish that deed, Bott traveled to Denver by a greenhouse-gas-spewing jet from Los Angeles.
Therein lies the paradox of making sustainability a goal when bringing so many thousands of people across the country to a single place: It would be much greener if everyone stayed home and picked a presidential candidate by conference call.
That, of course, would mean Democrats and Republicans missing out on all the fun. (One irony of Hurricane Gustav disrupting the start of the Republican National Convention this week is that climate scientists say such storms will become ever more common as greenhouse gas emissions continue rising.)
In downtown Denver, recycling bins were conspicuous. Without volunteers like Bott guarding them, though, many of the bins were simply used for trash.
The recycling and composting effort broke down as crowds gathered Thursday for Sen. Barack Obama's speech accepting the party's presidential nomination at Invesco Field. Piles of discarded Gatorade and water bottles littered approaches to the stadium as crowds milled in the hot sun waiting to pass security.
Damon Jones, a spokesman for the Democratic National Convention Committee, admits recycling efforts did not go as well at the football stadium. And he's not yet sure whether volunteers achieved a goal of diverting 85 percent of total convention wastes from landfills.
"Overall," Jones says, "we think they were fairly successful."
Other examples of mixed results: While many appreciated a program offering free bike loans, security barriers kept cyclists from riding within blocks of the convention center. The Denver 2008 Convention Host Committee had reusable water bottles placed in the welcome bags for delegates and media, but very few were visible inside the convention halls.
And as nice as it was that area hotels handled reservations electronically, to save paper, attendees of the convention were handed five or more large signs and placards calling for "hope" and "unity," and trumpeting the names of different speakers every night. Jones says green volunteers would have recycled these signs, but found very few: They apparently were taken as souvenirs.