The state attorney general's office may excavate areas around the Kaloko dam as part of its investigation into last month's deadly breach of the 116-year-old earthen structure.

State Attorney General Mark Bennett yesterday said he and members of his department's investigative team were on Kaua'i on Tuesday to inspect the dam, whose collapse last month killed seven people.

Bennett, who declined comment on the finding of Tuesday's inspection, said investigators and the state's engineering consultants are considering excavating the site to find out what happened to a key safety feature of the dam known as a spillway.

"I am quite certain that the facts about the spillway — whatever they may be — will come out," Bennett said.

State investigators have issued scores of subpoenas and have interviewed dozens of potential witnesses in an effort to find out whether the spillway was tampered with and contributed to the dam's collapse. Such a finding could result in criminal charges.

Several Kaua'i residents recalled seeing a concrete spillway on the dam that was later buried with dirt in 1998.

But an attorney for retired car dealer Jimmy Pflueger, who owns most of the land under the dam, said that to the best of his knowledge, the spillway was not on the dam but to the northwest of it.

Pflueger has denied that he altered the dam, and his attorney Bill McCorriston denied that Pflueger filled in its spillway.

McCorriston echoed sentiments expressed by U.S. Rep. Neil Abercrombie and members of the Kaua'i community that the attorney general's office has an apparent conflict of interest in investigating the Kaloko dam failure since the state is in charge of inspecting the dam and could be liable for some of the damage.

"Many people have expressed the opinion that Attorney General Bennett's intent is to blame everything on Mr. Pflueger and get the state off the hook," McCorriston said.

"The concentrated effort to establish a problem with the outflow unfortunately tends to reinforce that view. Whether the outflow had any substantive part in the dam's failure is a matter under study."

Bennett defended the state's investigation, saying he believes his office can be fair and independent. But Bennett said he would have no objection to hiring special deputies to conduct a probe or have the investigation conducted by federal officials or a special committee set up by the state Legislature.

"We're not going to be stubborn about it," he said. "We're going to ultimately do what we believe what's in the best interest for the public."

Reach Rick Daysog at rdaysog@honoluluadvertiser.com.