I don't understand the 8th paragraph of this news at all

Little known organisation has giant role in making world safe

THE HAGUE: The winner of this year's Nobel Peace Prize is a body that has spent years trying to rid the world of chemical weapons in relative obscurity and was recently thrust into the limelight by the Syrian crisis.

From Russia to the United States, Iraq and Libya, inspectors from the Hague-based
Organisation for the Prohibition of Chemical Weapons (OPCW) have been slowly but surely destroying the world's most dangerous chemical stockpiles.

Syria last month signed up to the Chemical Weapons Convention (CWC), which the OPC'W enforces, agreeing to hand over its chemical weapons for destruction under a Russia-US plan aimed at averting military strikes on the country in the wake of a devastating chemical attack on a Damascus suburb.

Previously one of only five countries not to have signed the global treaty, Syria accepted the Russian proposal last month and has so far won rare praise for its cooperation with OPCW inspectors, who arc already hard at work on the ground.

The OPCW has done a lot of work over the years but most people have only heard of them because of what has happened in Syria over the last two months," said Dan Kaszeta. a former officer in the US Army Chemical Corps who now runs a London-based consultancy in chemical defence issues.

We don't want to give any impression that we're focused on anything else other tban this mission," OPCW spokesman Michael Luhan said.

The organisation is led by Director General Ahmet Uzumcu, a Turkish diplomat. It began work in 1997 and has overseen the destruction of 57,000 tonnes of chemical weapons, mostly US and Russian arsenals.

8th paragraph >>>>>>>
"It's the slow steady laying down of bricks over the weeks, months and years, people sitting in control rooms watching this stuff going into the chutes," Mr Luhan said. "It's our persistence, without any fanfare ... it's the slow grinding work that we hope over time will be more appreciated."

But Mr Luhan said he did not want the awarding of the Nobel Peace Prize to overshadow its dangerous mission in Syria.

Chemical weapons were first used in combat in World War I. and again in 1988 against civilians in Halabja, Iraq, with the Chemical Weapons Convention finally drawn up in 1993 in Paris.

The questions are:
1. What the pronoun "it" refers to?
2. What is the bricks they are laying down? The organization?
3. Who are "people sitting in the control room" and what is the control room?
4.what is "this stuff"? The chemical weapons?
5. What does "going into the chutes" mean?