IOWA CITY – An Egyptian company planning to invest $1.4 billion to build a fertilizer plant in southeastern Iowa may have to pay for archaeological digging at the site because Native American artifacts were found there, the state archaeologist said Wednesday.

Artifacts such as pottery, stone tools and spear points that are likely between 1,000 and 1,600 years old have been found in clusters on the 300-acre site north of Burlington where Orascom Construction Industries hopes to break ground soon, State Archaeologist John Doershuk said in an interview. The discovery adds another layer of complexity – and potential controversy – to a project that has been criticized because it’s been promised more than $200 million in state and local tax subsidies.

A consultant hired by Orascom is conducting additional analysis of the land and will recommend whether any of the areas are eligible for the National Register for Historic Places. If any areas are eligible, Orascom would be required to pay for “a full-blown excavation” before building on them to allow archaeologists to recover anything of significance, Doershuk said.

Doershuk said that his office and the State Historic Preservation Office would get to offer input on the findings before any decisions are made. He said he hopes the issue does not cause construction delays, but it’s too soon to say how it might affect the plans.

Work could begin elsewhere on the property while archaeologists dig in affected areas, but the impact would “depend on where they sit within the footprint of that construction,” he said.

“From what I’ve learned so far, I wouldn’t be surprised if one or two of these site areas get designated as eligible,” he said. “But I’m still waiting for the full data so I can add my two cents.”

The pottery and tools recovered thus far aren’t particularly significant since similar items have been found before, he said. But the additional sampling and evaluation being conducted by Orascom’s consultant, the Louis Berger Group, Inc., is looking at whether the areas are potentially significant because of the amount of materials clustered and how they are preserved. Perhaps they will find the remnants of a house or an “activity area” where people cooked food or processed hides, he said.

“If those kinds of things are intact, then the artifacts start to tell us a lot about the life of the people,” he said. “That’s what they are trying to drill into right now.”

He said no human or animal bones have been found on the site, which had not been studied by archaeologists previously. It’s still unclear whether researchers will be able to trace artifacts back to a specific tribe, he said.