Valero has not yet tested the bottom of its berths, so it is unknown how difficult it will be to dispose of the materials when dredging is done, according to environmental manager David Land.

A typical tanker that calls at the Greenwich Township refinery is 600 feet long with a half-million barrels of crude. Another five feet of water would accommodate 1,000-foot tankers with a million-barrel capacity. Unlike Sunoco, Valero does not lighter oil from larger to smaller ships on the Delaware.

San Antonio-based Valero bought Mobil's 950-acre refinery last year for $228 million, jumping at the opportunity to become a player on the Delaware, where Mobil had been refining since 1917.

Valero processes 155,000 barrels a day and employs 540 people. This year, it expects to spend about $30 million in infrastructure improvements; next year, between $50 million and $60 million. While the investment is not expected to produce any new permanent jobs, it will sustain existing ones and create a wealth of construction jobs. There are no assurances, however, that any of these workers would be from South Jersey.

"Chances of duplicating this deal from scratch, I mean, this much land in New Jersey and the freedom to run a refinery are zero," says Harris. "These old refineries may change hands, but they'll never go away. They'll continue to be upgraded because this industry has a bright future."

The oil industry maintains it is only one of many stakeholders in the life of the river and therefore no more likely to contribute directly to the cost of the dredging than any other user. The industry claims it also carries a heavy burden in wages and taxes.

According to cost benefit analysis by the corps, about 80 percent of the savings derived from deepening the channel will accrue to the oil industry.

To Maya K. van Rossum, spokeswoman for the Alliance Against the Delaware Deepening, that amounts to corporate welfare.

"Taxpayers have to shell out this money," she says, "when the major benefactors don't spend a dime."