The House quickly passed and the Senate is considering a bill to give elderly members of Congress and extra $3,000 a year on their pensions if they will make this their last term - and Common Cause is backing the bill as a "reform."

Common Cause President David Cohen says it is worth the money to get rid of the members involved, or as he prefers to put it, to infuse "new blood into the institution."

The bill whizzed through the House on Sept. 23, without hearings, advance notice of debate. It would raise the retirement pay of veteran legislators by $3,000 a year if they resign before Jan. 3, 1979.

Cohen, whose organization normally resists bills like this, said in an interview that the purpose of the legislation was to encourage retirement of older members. At least, said Cohen, "that was the way the Speaker (Thomas P. (Tip) O'Neill Jr.) described it last spring."

According to Cohen, O'Neill first raised the idea of such a bill last spring, during the House pay-raise controversy.

At that time, the salary for an individual member went up from $44,600 to $57,500. Under the congressional pension plan, a 20-year member's retirement pay is set at 80 percent of his average salary during his last three years in Congress.

Because of the pay raise, an older member would have an incentive to run in 1978 since one more two-year term would qualify him to retire at 80 per cent of the new high salary level.

O'Neill, according to Cohen, "proposed a clear trade to get people out."

"We told O'Neill," Cohen said, "we support the concept but will not lobby for it."

Cohen also expressed his disapproval of the way O'Neill rushed it through the House. "He should have had a record vote," Cohen said.

But O'Neill apparently waited for the right moment before moving the Bill onto the House floor.

In August, a Library of Congress study was ordered up showing who would benefit from the bill. Some 35 House Democrats and three House Republicans, with 20 year of service, qualified for the full benefit - their retirement pay with the bill would be $46,000 a year. Without it, their pension would be $42.880.

Any member who runs in 1978 and wins won't need the coverage of the bill because he will have his three years at the new salary.

According to one member, there were some suggestions the bill should cover only those legislators who resigned before the 1978 congressional elections, as opposed to members who lost and then retired before their term was up.

That suggestion was put aside. The House GOP leadership decided not to oppose the legislation. Even Rep. Robert Bauman (R-Md.), the Republican gadfly who objects to anything costing money, kept mum. Bauman said later he was told the bill would only affect House and Senate staffers, not members.

The bill has now been sent to the Senate and turned over to its Governmental Affairs Committee.

No senators, according to Hill sources, have yet to show interest in the measure and only a handful would stand to benefit by its terms.

Meanwhile, back in the House, several members who would qualify for the pension increase have announced their retirements. Among them are O'Neill's good friend Rep. James Burke (D-Mass.), and Reps. George Mahon (D-Tex.) and W.R. Poage (D-Tex.). Among them there is enough potential Capitol Hill power to move any piece of legislation. It might not be easy, howere, if Cohen and Common Cause demand and get a roll-call vote on this particular reform.