DONALDSONVILLE — The Ascension Parish Council has approved rebating significant incentives to Methanex Corp. for relocating a $550 million methanol plant from Chile to Geismar.

Methanex, of Vancouver, Canada, announced in April it would bring a second methanol plant to Ascension Parish after initially announcing in January 2012 it would make a $400 million investment in the parish by bringing a plant to Geismar.

The incentives package would rebate a half-cent of eligible sales tax on the purchase of construction materials, with 45 percent of that going to Methanex and 5 percent going to the Ascension Economic Development Corp.

The expected rebate, approved Thursday, is estimated at $450,000.

The agreement also says that the rebate is conditioned upon the creation of 35 new full-time jobs in the parish, but it would be reduced if the company fails to meet that goal. Should Methanex create only 32 jobs, its rebate would be limited to 91.1 percent, the agreement says.

The council agreed last year to rebate its 1-cent sales tax on construction materials and equipment for the first plant, a rebate worth an estimated $1.61 million.

As part of the new agreement, Methanex agreed to purchase gas and water from the parish if it eventually can provide such service “at a reasonably competitive price.”

Parish officials have been exploring the possibility of buying natural gas from pipelines running through the parish and selling it at a profit to industrial users along the Mississippi River as well as working with Georgia-based startup Water and Power Cogen Development LLC on a parish-wide water plan that would tap unused saline aquifers to produce fresh potable and industrial-grade water.