Eichholz, 58, will face a maximum sentence of five years in prison and a $250,000 fine.
Chief U.S. District Judge William T. Moore Jr., who accepted Eichholz's guilty plea Dec. 29, will impose sentence based in part on a pre-sentencing report from probation officials.
Although Eichholz pleaded to only one count in a 77-count indictment, with prosecutors dismissing the remaining counts, probation officers were able to include information from the entire indictment when presenting Moore with a pre-sentencing report and sentencing guidelines.
The process is advisory only, with the ultimate determination left to Moore.
"I do understand that I am pleading guilty to one count of obstruction," Eichholz told Moore at the time.
In return, Assistant U.S. Attorney James Durham told Moore the government would dismiss the remaining counts.
Those counts included embezzlement, money laundering, mail fraud and false statements.
Durham said the government will not pursue enhanced sentencing for abuse of a position of trust and will recommend credit for acceptance of responsibility.
Also as part of the plea agreement, Eichholz has agreed to make restitution for losses by victims, Durham said.
Eichholz pleaded guilty to count No. 55, which includes allegations involving a number of loans from the plans, at least one of which involved Delta Building Systems Inc., a Statesboro company Eichholz owned.
The indictment stems from what prosecutors charge was embezzlement of more than $950,000 from the benefits plans between 2001 and 2008.
The government probe targeted whether Eichholz was using the plans' assets for his own use.
It found more than $227,000 invested in Delta, which led investigators to question Eichholz about his ownership.
Eichholz was told that, under the Employee Retirement Income Security Act, he was barred from investing plan assets to a business he owned, Durham said at the change-of-plea hearing.
When asked whether he owned Delta, Eichholz told Moore: "I falsely stated no, and I knew at the time that I was the owner of 100 percent stock.
"I understood at the time the answer given could mislead the investigator and obstruct the investigation."