A timeline for cleaning the Gowanus Canal is taking shape, though it still remains unclear when, exactly, the U.S. Environmental Protection Agency plans to list the polluted waterway.

The decision to place the canal on the National Priorities List, paving the way for a Superfund cleanup, is being handled “at the very highest, highest levels of the agency,” said Walter Mugdan, an EPA official, at a December 3 community meeting on the project.

At the meeting Mugdan announced the EPA plans to finish studying the canal, and decide on a cleanup remedy, in 2012. As it turns out, the EPA could perform all of that work- several years’ worth of studies and testing- before deciding whether or not to list the site.

“We can do everything all the way up until putting a shovel in the ground without listing,” Mugdan said.

The EPA typically lists polluted sites in September or March, though it can do so at anytime throughout the year.

After the September deadline came and went, EPA officials said a decision on the Gowanus would come by the end of the year. Two weeks into December, that deadline could be in jeopardy, too.

That hasn’t stopped the EPA from starting phase one fieldwork on the canal.

The agency is proceeding with a remedial investigation (RI) to determine “the full extent” of contamination in the sediment of the 1.8-mile canal. The Gowanus, completed in 1869, served as an industrial shipping channel for over a century.

The EPA expects to finish the RI by late 2010, and a subsequent feasibility study (FS) to identify potential cleanup alternatives by late 2011. The EPA anticipates selecting a final cleanup plan the following year, in 2012.

Mugdan said the agency has the funding to complete the study phase of the project. Companies responsible for present or past pollution of the canal would finance the cleanup itself. (So far the EPA has identified five leading potentially responsible parties; they include the U.S. Navy, National Grid and Consolidated Edison).

Christos Tsiamis, the EPA’s project manager for the Gowanus, said the remedial investigation will be long and complicated, involving the collection of large amounts of data on the canal’s contamination.

A bathymetric (underwater depth) survey will be conducted. The EPA will collect sediment, air, fish and crab and water samples. Small ground water wells will be drilled to test ground water levels and contamination. The impact of the combined sewer overflow system will also be studied.

Results from these studies will paint the chemical portrait of the infamously foul-smelling canal, where heavy industrial companies polluted with impunity for years before such things as strict environmental regulations existed.

Christos said the investigation would be finished on time if everything goes according to plan. “Of course that does not include contingencies and as you know there are always contingencies,” he said.

However, he added, “We are fairly confident we can accomplish” the investigation in time to start work on finding a cleanup solution.

Christos heads a large team of EPA experts who will work on the canal in coming months. In a show of scientific force the group was assembled and introduced at the meeting for the first time. The roll out made it clear the federal government is moving forward with the project, whether the site is listed by year’s end or not.

Whether it comes in the next weeks or much later, it appears that listing the site at some point is a foregone conclusion; the EPA is not in the habit of proposing sites for the National Priorities List without following through with a listing.

Before doing so, however, the agency must issue a formal response to the 800 public comments it received on the project.

Mugdan said the extraordinarily high number of comments and interest surrounding a possible Superfund cleanup has drawn the attention of top EPA officials in Washington D.C., where the ultimate listing decision is being made.

He said in almost all cases the agency lists sites within a year of proposing them. The Gowanus Canal was proposed for NPL status last April. It is “very, very unusual” for a decision to take longer than one year, he said.

Senator Velmanette Montgomery said the EPA is on the right track.

“I have been convinced that we’re moving in the right direction,” Montgomery said. “I feel very confident that if the EPA lists the canal for cleanup we are going to be much better off.”