Evan L. Hultman, who is in line to become U.S. attorney for the northern district of Iowa, hasn't been nominated formally, but he has run into trouble from the Senate Judiciary Committee, which eventually would have to approve his nomination.

Hultman was U.S. attorney for eight years under Presidents Nixon and Ford, and was Iowa attorney general and GOP gubernatorial candidate in 1964.

He was brought before the committee yesterday to explain a number of "contradictions" and "misstatements" in his testimony before the committee last December. He had been subpoenaed then to defend his handling of a controversial case that was under his jurisdiction for several years in the early 1970s.

Blaming any contradictions on lapses in memory, Hultman told the committee that it was impossible for him to recall legal details that occurred as long as a decade ago.

A review of the situation by the office of the Senate legal counsel found that "our own review . . . persuades us that the material does not reach the level of known falsehood that constitutes perjury . . . . At most, the material may be read to cast doubt on Mr. Hultman's credibility . . . . "

Sen. Dennis DeConcini (D-Ariz.), who chaired yesterday's hearing, said he had turned that evidence of contradictions in Hultman's testimony over to the Justice Department without recommendation earlier this year.

Central to the controversy over Hultman is the case of John A. Nard, a Pittsburgh building contractor who lost a million-dollar breach-of-contract suit with the Armour meat-packing company of Iowa and later pleaded no contest to related tax-evasion charges.

Hultman became involved in the case when Nard asked him to investigate alleged perjury by company employes in his earlier trials. Records indicate that Hultman believed there was perjury involved, but, after three grand juries, he had obtained no indictments, and Nard was launched on a crusade to prove that Hultman, either through incompetence or political complicity, had not done his job.

The case is complicated further by the fact that, before he was elected to the Senate, Sen. Orrin G. Hatch (R-Utah), chairman of the Judiciary Committee, served for a number of years as Nard's attorney in this case.

To avoid a possible conflict of interest, Hatch ended the relationship when he was elected, waived $25,000 in legal fees that Nard owed him and turned over direction of the hearing to DeConcini.

A staff report released yesterday by DeConcini and Hatch said, "There is persuasive evidence that Nard was the victim of perjured and misleading testimony, and that Hultman and other Justice Department officials abused the prosecutorial discretion inherent in their posts by failing to follow up on the many leads Nard made available to them."

The report concluded that Hultman "grossly abused his office," and added, "Unless and until his record in this matter is cleared, the gravest questions will remain regarding Hultman's suitability for further federal appointment."

It said "mismanagement" in the investigations he headed was "so rife as to raise serious questions about Hultman's professional conduct."

Hultman countered yesterday that "two federal District Court judges, an appellate court and three grand juries" did not believe Nard after they "listened to all the evidence."

He said "every grand juror referred to" in the DeConcini-Hatch report "views Nard in a negative manner, some going as far as describing him as a 'crook' and 'shyster.' "