However, Baird said the document contained no top secret or classified information.

"It's certainly bizarre," he said. "I'm told two things: that it's neither classified nor secret and that it's stuff that could be available under access to information."

Still, Baird said his department takes document security seriously and he's asked officials to find out how this 131-page document came to be found by a passer-by on a street in a rain-stained, tire-marked, brown envelope.

The CBC, which was given the document, reported that it assesses the security of a database used to track and prosecute polluters and environmental law-breakers and details how a hacker could access, attack and corrupt the data.

The phrase "Protected B" is at the top of each page.

Protected B is the second lowest grade of classified government documents. Environment Canada spokesperson Julie Hahn said it applies to letters of complaint, criticism or injury, research or scientific notes and findings before conclusions have been reached and Treasury Board letters, agendas and minutes that do not deal with subjects of national interest.

According to a departmental brochure on the handling of sensitive information, Protected B documents are supposed to be stored in "approved security cabinets" and destroyed using an "approved shredder." They are to be kept in double envelopes, the inner one stamped with a security marking, transmitted only via secure fax machines and discussed only via secure phones.

The discovery was reminiscent of a March incident in which a sheaf of blueprints for a new headquarters for the military's counterterrorism unit were found stuffed in the trash on a downtown street.

The company which produced the plans said the building project wasn't tagged as a security matter.

In May, Maxime Bernier resigned as foreign affairs minister after admitting he'd left classified government documents for more than a month at the home of his former girlfriend, a woman with past ties to criminal biker gangs. No one in government, including Bernier, noticed the papers were missing until the ex-girlfriend returned them.

Paul Dewar, an Ottawa New Democrat MP, said the combined security lapses raise serious questions about the government's ability to secure sensitive documents.

Dewar said bureaucrats have complained to him that the Conservative government has instituted a policy of classifying almost all documents, to the point that bureaucrats can't even share them with colleagues in the same department. Yet when a document is lost or turns up unexpectedly in public, the government routinely says it wasn't particularly sensitive.

"This government is so consumed with control of information and secrecy yet they don't seem to be able to get the fundamentals right," Dewar said.