Pay levels for members of the elite new government corps of supergraders, the Senior Executive Service, would go up an average of 3.36 percent this October under the president's alternate pay plan. Boosts for most rank-and-file civil servants, and the military, will be 7 percent. Employes in the two lowest federal grades -- approximately 20,000 people in GS 1 and 2 jobs -- will get slightly more than 9 percent.

Congress has less than 30 days to act on the president's plan. If it does nothing -- as expected -- the raises go into effect with the first pay period on or after Oct. 1 for white collar civilians, and Oct. 1 for military personnel. D.C. Government white collar workers, Foreign Service and VA medical personnel also will get the 7 percent boost. In metropolitan Washington an estimated 400,000 people will get the raises, adding an extra $2 million per day to the local payroll.

The raises for higher-level federal workers are less certain, since Congress controls the ceiling on civil service pay. That ceiling is based on a substantial differential Senate and House members insist upon beyond their own nearly $60,000 rates and the $47,500 federal career ceiling.

If Congress "allows" itself a raise -- of perhaps 5.5 percent if not the full 7 percent -- pay for "frozen" federal workers will go up proportionately from the $47,500 level. If Congress wisely chickens out on its own raises, for political or economic reasons, the lid will remain on.

Whatever happens, here are the new rates proposed by President Carter for the 8,000 members of the Senior Executive Service: ES1 -- $47,889 ES2 -- $49,499 ES3 -- $51,164 ES4 -- $52,884 ES5 -- $54,662 ES6 -- $56,500

Retiree Raises: Retired federal and military personnel are not included in the 7 percent October pay raise unless they have been reemployed by the government. They will be getting a cost-of-living adjustment in October, their second inflation-triggered boost of the year. The October raise, actually effective Sept. 1, will be for 6.9 percent.

Nahan T. Wolkomir: The National Federation of Federal Employes is planning a memorial observance in LaFayette Park for its late president. Friends and associates from government are invited to attend. Call NFFE headquarters at 862-4435.

Public Employes Department: The AFL-CIO umbrella organization covering public unions celebrated its fifth birthday the other day. Howard McClennan, head of the Firefighters union, is president of PED. McClennan was busy yesterday playing a lead role in delivering and raising funds for the Jerry Lewis Telethon on WTTG-TV.

Senior Executive Service: There will be a Sept. 20-21 seminar on the new elite corp of federal supergraders at the Key Bridge Marriot. The Classification and Compensation Society is sponsoring the session ( $100 members, $125 nonmembers), limited to 100 people. Call Mel Takahashi at 694-3416 for details.

Smithsonian Institution has promoted Walter J. Boyne as its executive officer. He's a retired Air Force colonel, aviation writer and recently was curator of the air and space building.

Payroll Supervisor: Federal Home Loan Bank Board has a Grade 8 or 9 opening.