The Audit

How to measure single-use plastic in your material waste stream.

WHEN A COMPANY DECIDES TO ASSESS the amount of single-use plastics entering the waste stream from their facilities, they often hire an outside firm to conduct a waste audit, not only to better understand how their offices were performing with respect to recycling, but also to understand what opportunities were available to increase recycling as well as reduce waste generated on-site.

Information Artwork by Douglas Gayeton - click to enlarge

Three things an audit hopes to address:

Contamination Highly contaminated recycling and composting can sometimes be redirected to the landfill, which effectively negates the purpose of separating materials out to begin with.

Waste diversion The landfill stream for most companies typically contains between 50-75% recoverable material, which means that the majority of material being sent to the landfill could actually be recovered through recycling or composting.

Waste prevention Single-use plastics, excess food, and packaging materials like cardboard and styrofoam are all materials that can typically be reduced and occasionally eliminated entirely.

Deciding to do an Audit.

THE FOLLOWING CHECKLIST PROVIDES GUIDANCE for what to look for when conducting an audit with an outside firm. This will help you prepare before the audit, and to better understand what to do with the data once it’s been received.

When hiring an outside auditor, be sure to make a checklist of priorities.

These can include:

  • Which spaces generate the most waste
  • How much contamination is happening across my major streams
  • Which spaces incorrectly place the wrong material in the wrong stream
  • Breakdown of materials being generated on-site
  • Which materials are commonly making it in the wrong stream
  • What recommendations are available to address the biggest opportunities in each space.

Preparing your team

Before conducting an audit, be sure to prepare your team and facility for the work ahead:

  • Identify all team members who manage waste on-site (ex: facilities team members, warehouse managers, cleaning team, food team, etc)
  • Engage the team at least two weeks in advance and align on purpose of audit
  • Ensure the waste auditor is involved early in planning and participating in alignment calls with the internal team
  • Identify a space for the audit to take place (ex: near waste corral, parking lot, covered area, or even off-site)

Determining the locations and duration

Generally speaking, a 1-3 day waste audit will be useful. For commercial office space, a 2-day waste audit is recommended especially if the waste profile varies due to guests or events or high influx of waste generated. The longer a waste audit is conducted, the more useful insights can be gathered.

An audit identifies primary recoverable materials (materials that are relatively easy to capture like food waste or office paper) and that information is used to tweak the internal infrastructure (containers and signage) or develop an employee education campaign. It can also quantify the amount of waste generated so a company can target the most easiest way to reduce their use of these materials.

Information Artwork by Douglas Gayeton - CLICK TO ENLARGE

What to expect when receiving audit results

  • How much total waste you generate
  • What percentage goes to landfill/recycling/composting
  • What is your biggest category of waste being generated on-site (ex: cardboard, plastic wrapping, food, etc) 
  • How much waste is being incorrectly placed into the wrong waste streams
  • – Where your biggest opportunity for increased landfill diversion
  • – What a landfill diversion goal could be if all waste was sorted correctly

What departments are most interested in the results of an audit?​

Facility operations leads, which can include the facility manager at a site, food operators in charge of the cafeteria, and even janitorial managers as it may impact how they operate and who on their team they need to communicate to affect change. Site leads are usually responsible for the culture they are hoping to shape at a given building/campus, so they can also be a critical stakeholder in the process to ensure backing of any changes that may impact building occupants.

As soon as the results are available, meet with the facilities teams to highlight and identify the stakeholders responsible for the generation and management of waste. Agree on an action plan based on the results of the waste audit, and agree on what is reasonable to implement.

For any changes that will impact building occupants, be prepared for early engagement with key leads to ensure they are supportive of whatever changes are put in place. Prior to any rollout ensure the building occupants have an appropriate heads-up so they are not surprised. Reinforce, as always, what outcomes you expect from these enhancements so they understand what the team is ultimately trying to accomplish.

How to Conduct a Plastic Audit.​

An interview with Stefan Moedritzer

TO FIGURE OUT WHAT WASTE MATERIALS (including single-use plastic) enter the waste stream from a company, building or facility, start by looking at what’s in your garbage.

Stefan Moedritzer formerly managed Cascadia Consulting’s corporate and institutional waste work, where he helped universities, e-commerce, technology, retail, healthcare and food service companies quantify their environmental impacts and develop implementation plans to reduce their waste generation while increasing their waste diversion (the amount of material kept out of the landfill).

When an organization realizes the sheer amount of waste they are generating and how much of it can be recovered, this is typically a fairly eye-opening moment that spurs action.

What types of waste audits do you perform?

They depend on our client’s needs. For many companies we conduct a several day “snapshot audit” that provides detailed data regarding the quantity and composition of the waste generated onsite. These audits are a great way to identify the low-hanging fruit and develop actionable plans to reduce waste, increase diversion, and ensure that your recycling and compost streams stay as clean as possible. Some clients, such as the City of Seattle or the State of California, need more detailed data so they can track or develop policies like a statewide composting mandate or a plastic bag ban. For these studies, we collect and hand-sort tens of thousands of pounds of material (sometimes into up to 400 different waste categories) over multiple seasons to ensure that the data we collect is both representative and statistically significant.

What prompts someone to perform a waste audit?

The primary driver for a private sector audit is to increase waste diversion – the percentage of material that is kept out of the landfill through recycling, composting, or other means. Tracking and reporting for other sustainability areas like energy and water has long been metered and standardized, yet waste remains an enigma. An audit helps to identify what exactly a business is generating, and what can be done to reduce this waste and ensure materials are going into the correct container.

What do you look for when hiring an outside firm to conduct an audit?​

Look for a firm that has experience conducting audits with your type of facility. Common auditing pitfalls include not collecting representative samples, inexperienced sort teams, data entry and analysis errors, and insufficient equipment or safety procedures. You want a firm that will get the job done accurately, safely, and with minimal interruption to day-to-day operations.

Why are people so interested in discovering alternatives to single-use plastics?

Plastics have rightfully been getting a lot of media attention the last 3-4 years. They are cheap, lightweight, easy to manufacture and last an extremely long time, which has been fantastic for the packaging industry and other industrial applications. More and more light has been shed on the downstream effects of this material, and we now know the vast majority of plastics are not being recycled properly and are ending up in streets, oceans, parks, and even our food supply. Plastics are a huge environmental and social justice issue (check out the Plastic China documentary). Also, most plastics are petroleum-based, which contributes to fossil fuel usage and increased GHG emissions associated with that. The good news is that many single-use plastics have durable or non-plastic replacements already available, like many foodservice or packaging items. Increased awareness and attention on single-use plastics is leading to new innovation on this front as well.

What are the criteria used to determine the type of audit to be performed?

Waste audits vary greatly in the amount of granularity in terms of data, but overall the theme and desired outcome are the same in terms of identifying which material outputs a team should prioritize along with how they are currently performing and what there potential for increased recycling may be.

How long does an audit take? Is it one day or multiple days?

This is entirely dependant on budget. More audit days = stronger data. For companies that are conducting their first audit, I would recommend collecting more samples over more days and focusing on a small list of materials, maybe 6-10 categories. This will help to establish a strong baseline and can identify the low-hanging fruit. For a company that already has a strong understanding of their waste stream, deeper dives are necessary to take program performance to the next level. These audits often involve larger sample sizes or more detailed materials lists, up to 40-50 distinct categories.

What factors can affect the accuracy of an audit?

All audits are based on collecting and characterizing samples. The first step is to ensure that your sample is representative of the location you are auditing. To do this, it is best to start with at least a full 24-hour sample and audit all areas within a site. For example, if you are auditing bathrooms at an office building from 5am-8:30am, the resulting data is not going to tell you a lot about what that site is generating overall and what the opportunities are for improvement.

Representative also means selecting the right day of the week; Monday or Friday waste generation may be different than the middle of a week due to reduced head-counts. The audit should represent typical operations; make sure there are no special events or holidays during your sampling window. Seasonality can also affect your results; some types of locations, such as restaurants, may be more or less busy depending on the season, or generate different types of waste at different times of the year.

What is the most useful thing you can learn from an audit?

The most useful takeaway from an audit for me is the amount of “good stuff” that is going to the landfill. Once an organization realizes the sheer amount of waste they are generating and how much of it can be recovered this is typically a fairly eye-opening moment that spurs action.

What are the most typical types of single-use plastics you look for when conducting an audit?

For an office building or a foodservice establishment, the most prevalent single-use items tend to be plastic films (such as bags or food packaging liners), plastic water bottles, and food service items like cups, takeout containers, and cutlery. More industrial settings, such as manufacturing or distribution, typically generate large amounts of expanded polystyrene (e.g., Styrofoam(r)), shrink wrap, and bubble wrap or other plastic packaging cushioning.

Audit results.

A typical “day in the office” for the Waste Sort team: Jess Halter and Maggie Moellering. They enter waste weights and types into a cloud-based database, and review field data for quality assurance.

Conducting your own audit.

NOT READY TO HIRE a company to conduct an audit?

Here are a few tips for conducting your own audit and getting a handle on the amount of single-use plastics that goes into your garbage each day.

  • Spread the tarp out.
  • Place one garbage bag on a portable scale set on the open tarp.
  • Weigh the plastic bag and enter data into the Audit Log.
  • Open the plastic bag with a box cutter.
  • Empty the bag onto the tarp.
  • Note all materials present and enter into date into the Audit Log.
  • Alternatively, place materials in specific bins (aluminum cans, glass bottles, plastic utensils, plastic bottles, snack food wrappers, etc.)
  • Place the rest of the garbage back into the bag and tie it up with twist ties.
  • Repeat with the rest of bags.
  • When audit is complete, weigh individual bins to get total amount of waste material by type.
  • Plastic waste into remaining bags and place in garbage.
  • Wash up with soap, water and disinfectant wipes.

Amity Lumper

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The qualities that make plastic useful—lightness, lower cost, durability—can also make plastic a challenge for communities and ecosystems. Single-use plastics, such as carry-out bags, wrappers, and food service items, weigh so little that they can be carried by wind or water, sometimes for many miles, littering our neighborhoods, natural areas, and precious waterways. Yet their lightness makes them virtually invisible.

The power of a waste audit lies in making the invisible visible.

With a proper waste audit, we can better understand how—and to what extent—single-use plastics are woven throughout supply chains, products, services, and operations. And this awareness—bolstered by data—empowers us to direct intervention and investment in areas that will truly make a difference.

Cascadia’s mission is to inspire and empower communities everywhere to protect and restore our world. Audits are one of the most effective tools we’ve found for empowering clients to take more ownership of their waste. With reliable data, organizations have been able to reduce or eliminate single-use plastics in favor of durable or compostable alternatives; reconfigure supplier contracts to replace plastic packaging with sustainable alternatives; educate employees and customers about proper sorting and waste management techniques; and correct inefficiencies.

If you’re considering an audit for your organization, thank you. This eye-opening experience will equip you to see the unseen and ultimately help solve one of the biggest environmental challenges faced by our world today.

Cascadia Consulting Group is a small, 100% women-owned environmental consulting company based in Seattle, WA. The company provides a broad range of environmental consulting services related to resource conservation and materials management, climate change mitigation and adaptation, sustainable transportation, stormwater pollution prevention, equity and inclusion, and natural resources planning.