Earlier this week, President Obama announced a seemingly straightforward goal: Reduce the government's greenhouse gas emissions by encouraging employees to bike, carpool or take public transportation to work.
But such indirect emissions are hard to quantify, and federal officials are still figuring out how they will measure agencies' progress.
So far, the White House Council on Environmental Quality has drafted guidelines for only a handful of indirect emissions, including employee travel and commuting, emissions from contracted waste disposal, and inefficiencies in the transmission of purchased electricity. But that is just a small fraction of how agencies might indirectly produce greenhouse gases.
"If you think about the universe of indirect greenhouse gas emissions, the list is long," said Michelle Moore, a CEQ official tasked with promoting federal sustainability efforts. "Looking into the future, we do anticipate that there will be opportunities for continuous improvement."
Most of the government's focus in recent months has been on direct emissions, which Obama aims to cut by 28 percent by 2020. Known as "scope 1" and "scope 2" emissions, they include emissions from sources that include company-owned vehicles or purchased electricity. But indirect emissions -- or "scope 3" emissions -- are not within an agency's direct control and are harder to accurately measure.
White House officials are already looking to agencies to help pave the way. Obama's goal of reducing indirect emissions by 13 percent in the next decade is based on agencies' own estimates of what they can accomplish.
Plans are wide-ranging, Moore said; agencies in large cities could subsidize public transportation, for example, while agencies in rural areas might focus more on cutting indirect emissions through employee business travel, among other things.
"It's not a one-size-fits-all government," Moore said. "We're comfortable that the agencies and the goals that they submitted will work toward the leadership challenge that the president gave us."
But agencies are still waiting to find out how they will measure their progress.
Earlier this month, CEQ posted online a draft copy of the "Federal Greenhouse Gas Accounting and Reporting Guidance," along with a slew of technical equations created by the General Services Administration.
The guidelines include instructions on how to measure a few sources of indirect emissions. For federal employees' daily commutes, for example, the guidelines recommend using "voluntary questionnaires" to collect information on the frequency, one-way distance and mode of transport of an employee's commute. Once the information is collected, agencies can enter the data into a GSA-created formula to come up with the total emissions from their employees' commutes.
But the guidelines also allow for a lot of flexibility. Agencies are allowed to come up with their own methodology, as long as they fully report that methodology to CEQ and the Office of Management and Budget.
Agencies will have to submit their first "inventory" reports on their direct and indirect emissions by the end of January and will then have to update those reports annually. But the guidelines could change in coming years; CEQ plans to regularly update the standards, especially for indirect emissions.
The White House also hopes agencies will increase their goals in cutting scope 3 emissions "as the Federal community continuously improves its ability to identify and account for these emissions," according to the draft guidelines.
Click here to read the draft guidelines.
Click here to read the technical support documents.
Clarification: This story was updated to clarify rural agency plans to reduce indirect emissions, and to clarify that agencies' first inventory reports are due by the end of January.