Paper farecards will be phased out of the Metro system by December 2015. (Gerald Martineau/For The Washington Post)

Here is Adam McGavock, Metro’s sales director, describing what happens when a subway rider sticks a paper Farecard in any of the rail system’s 1,000 or so mezzanine gates.

“What pulls your card in is a big rubber belt about that long,” he says, spreading his arms as far as they’ll go. “It’s motorized and running on a bunch of pulleys, and the pulleys have to be lubricated. The belt has to be tensioned and adjusted. It has to have powder put on it to maintain the exact right stickiness and durometer, okay?”

He takes a breath. “So the belt grabs your card and drags it across the mag-stripe reader. If you opened up the gate, we’d recognize the magnetic D-pad reader, like you see on an old reel-to-reel tape deck. Those have to be cleaned with rubbing alcohol and a Q-Tip.”

He says: “Then there’s a rubber stamp that has to go into ink and stamp the value on your card — boom, like that — before it pops back out. I mean, really, it’s a miracle of engineering. When you look at how this thing works, that it actually functions as well as it does, it’s a brilliantly made machine. For 1968.”

Time now to say goodbye to the past. Thirty-eight years after the opening of Washington’s underground transit network, which has become the second-busiest subway in America, the demise of the paper Farecard is finally at hand.

It’s another relic of the 1970s vanishing into Metro history, like the transit agency’s first generation of subway cars. Those are antiques of technology and will soon be retired, replaced by a 21st-century model known as the 7000 series.

Same with paper: It’s way too outdated. In the next year and a half, starting with an expected contract award this month, Metro plans to spend almost $9 million to retrofit about 500 Farecard dispensers throughout the rail system so that they will sell only plastic, reusable computer-chip SmarTrip cards.

By December 2015, if all goes as scheduled, transit officials say, only one small component of those ancient belt-and-pulley fare gates will continue to function: the electronic SmarTrip card readers that were installed in the late 1990s.

The retrofitting is just the first short-term phase of a nearly $200 million plan to radically change the subway’s fare-collection system in coming years. By 2020, Metro says, a new generation of gates, featuring digital “near-field capability,” will allow riders to pay with credit or debit cards, a cellphone or an improved type of SmarTrip card without removing the plastic or phone from their pockets or bags.

The goal, McGavock says, is to eliminate the huge maintenance costs associated with paper Farecards. While more than 90 percent of Metro passengers use SmarTrip cards these days, he says, fare machines still dispense about 2 million paper cards each month, which cumulatively take a toll on the gates. Although the gates were manufactured at different times, he says, all were made with the same 1960s technology.

There are two types of refrigerator-size Farecard dispensers in the rail system, blue ones and brown ones. Both issue paper Farecards and allow customers to add value to SmarTrip cards. The blue machines, about 500 of them, accept cash and credit and debit cards. The older, brown machines take only cash.

Jim Bongiorno, the transit agency’s technical manager, says that after a contract is finalized, probably within a few weeks, the company Metro hires will begin building new insides for the blue machines. That job is expected to be finished by October 2015. From then until December 2015, Bongiorno says, the new inner workings will be installed in the blue machines. After that, they will dispense only SmarTrip cards.

Refitting the brown machines to not only issue SmarTrip cards but also accept debit and credit cards would be too costly, he says. Although the brown machines will stay in use, as portals for adding value to SmarTrip cards, they will no longer dispense paper.

After December 2015, anyone with a leftover paper Farecard will still be able to use it, Metro says. Paper cards won’t be sold anymore, but the gates will continue to accept them during a transition period of a few months. Then paper will disappear from the system.

Metro introduced SmarTrip cards in 1999 (and added a $1 surcharge to paper Farecards in 2012) in an effort to move customers away from paper. The SmarTrip technology that the transit authority uses — which is also outdated — was a marvel of its time compared with the clunky paper-processing machinery, which had been the only option.

Available at some stores and from machines that look like ATMs in station mezzanines, a SmarTrip card costs $10, including a one-time $2 fee for the card and $8 of initial fare value. When the blue fare machines start dispensing them, Metro says, there will be a one-time $2 fee for the card, but the rider will be able to choose any initial fare value.

As for the SmarTrip card targets installed in fare gates in the late ’90s, they occasionally give riders fits, forcing them to tap-tap-tap their cards. But fixing them is a breeze.

“They have no moving parts,” McGavock says. “The device itself could fit in your pocket. It can be removed and replaced with a phillips-head screwdriver in about three minutes. It requires no preventive maintenance. There are no adjustments that need to be made.”

Scheduled for later this decade is a far more significant upgrade to the fare-collection system, Metro says.

The technology company Accenture, awarded a $184 million contract by the transit authority in January, will oversee the replacement of the system’s old fare gates with gates that use “near-field” technology. Metro says it will introduce a new “contactless” SmarTrip card that a rider can use without having to tap it to the target.

“Not to go too far down the road of geekery here,” McGavock says, “but SmarTrip was developed in the ’90s. We didn’t have things like cloud computing and high-speed data connections. It’s an older-style system, and it’s also going to go away.”

Because of the way the blue machines are being retrofitted, they will be able to dispense the new version of a SmarTrip card without any changes, Bongiorno says. The ATM-like SmarTrip dispensers that are currently in use won’t require refitting either.

In a pilot program, Metro says, it plans to install some new fare gates in 10 rail stations and new, advanced fare receptacles on some buses along six routes early in 2015 and recruit 2,000 volunteers to use them regularly for a while. The full rollout of the new gates and receptacles is scheduled to start in May 2017 and take three years.