After the devastation of Hurricane Maria, a man-made disaster may now be hurtling toward Puerto Rico in the form of Congress's tax overhaul plan.

Puerto Rican government officials and the island's oversight board appear to agree on one point: the bill could be disastrous for the island.

They are most concerned about the House version of the bill, which would impose an excise tax of 20 percent on products manufactured by a mainland company’s foreign subsidiaries. Puerto Rico is a U.S. commonwealth, but it is considered a foreign jurisdiction for tax purposes, so it would be subject to the tariff. And that could deprive the island of much-needed funds.

Francisco Pares, an assistant secretary in Puerto Rico’s treasury department, testified at a meeting in Manhattan Tuesday that the tax could cost the island about one-third of its revenue and risk thousands of jobs by prodding U.S. companies to shut down their manufacturing operations.

Members of the board said they had raised their concerns with House members.

The oversight board, which has the final say over the island's fiscal affairs, was created last year after Puerto Rico’s governor announced it would be unable to pay back the more than $70 billion it owed creditors.

Puerto Rico’s economy faces steep challenges. Representatives from Puerto Rico’s Treasury Department said government revenues would decline by about 25 percent in the final fiscal quarter of the year.

There was one silver lining. Early estimates had forecast that more than 470,000 residents would relocate to the mainland. But officials say the data now leads them to estimate that about 340,000 people, or 10 percent of the population, could leave over the next two years.