2022-009 Recycling Contamination Q1 FY21-22Date: 1/28/2022 Report No. 2022-009
INFORMAL STAFF REPORT
TO MAYOR AND CITY COUNCIL
SUBJECT:
Quarterly Recycling Contamination Update October 2021 – December 2021
BACKGROUND:
The City of Denton Solid Waste and Recycling Department (SWR) has diligently worked towards
reducing recycling contamination throughout FY 20/21. SWR implemented a cart tagging program
in July of 2021, which is part of a strategy to reduce contamination from homes, apartments, and
businesses to increase the diversion of material from the landfill and improve diverted,
programmatic material quality.
For the three (3) month period between October 2021 thru December 2021, SWR has collected a
total gross recycling tonnage of 2902 from residents, multifamily units, and commercial partners
and a net tonnage of 1569 resulting in a 46% overall contamination rate. This is a decrease of 19%
from Q1, FY 20/21.
Figure 1: * FY 21/22 data is partial year
46%47%44%
0%0%0%0%0%0%0%0%0%
64%64%67%68%67%61%55%59%52%54%56%
45%
0%
10%
20%
30%
40%
50%
60%
70%
80%
Overall Contamination Rate
FY 21/22 FY 20/21
878
990 1,034 998 1,018
1,172
-
200
400
600
800
1,000
1,200
1,400
October November December
Gross Tons
FY 21/22 FY 20/21
472
523
574
363 363 388
-
100
200
300
400
500
600
700
October November December
Net Tons
FY 21/22 FY 20/21
Date: 1/28/2022 Report No. 2022-009
DISCUSSION:
Residential
The residential contamination rate for the first three months in FY21/22, October 2021 – December
2021, was 48%. The source of this contamination is:
1. Non-programmatic recyclable material including plastic film, soiled cardboard, and
Styrofoam.
2. Bagged material. Due to the increased quality standards caused by a closure of foreign end-
user markets all material should be empty, clean, dry, and loose. Bagged recyclables are
considered contamination and will be diverted to the landfill.
3. Aspirational recycling by well-meaning residents using their recycling cart as a donation
station. Aspirational materials include textiles, small appliances, sporting goods, etc.
The City of Denton can only accept programmatic material including mixed paper, plastic bottles
and jugs 1-7, aluminum cans, cardboard, cartons, and glass bottles and jars as part of its source-
separated diversion program.
To address contamination concerns, a cart tagging program was introduced. Routes are chosen
by the highest percentage of contamination per month for a concentrated approach. Two interns
walk these routes ahead of the collection crews auditing carts, removing non-programmatic
material, and leaving an education tag. The cart tagging program consists of a 3-tag process.
Recycling Star is given to residents doing a spectacular job at recycling. A Notice tag is left
when a resident is doing well but has a few common contaminants. An OOPS tag/Contamination
tag is given when the cart contains 15% or greater contamination. The interns lift each lid and do
a quick visual inspection. If a cart is labeled as contaminated a tag will be left and the cart is not
collected. The resident is then instructed to remove contamination and the container will then be
collected on the resident's next collection day. A second inspection would occur the following
week to see if the resident cleaned up the contamination. If not, the container would be tagged
again. This information allows us to focus efforts on customers who are consistently not
compliant with program requirements. The top 5 contamination items are plastic bags,
Styrofoam, yard waste, bulky items, and textiles. In December, we visited 16 routes, inspected
1549 homes, and left a contamination tag at 20% of homes.
Date: 1/28/2022 Report No. 2022-009
SWR takes the information of routes and types of items responsible for the contamination and will
create specific, focused educational opportunities and distribute via Social Media posts, HOA
outreach, Recycle Right Q&A, apartment bags/flyers, and education material.
Commercial
The Commercial contamination rate for October 2021 – December 2021 was 45%.
Like the residential program, we identify the routes that were frequent offenders of high
contamination monthly. The type of contamination encountered in recycling loads was similar to
that in residential loads except for increased wood and furniture. The most contaminated routes
are audited and dumpsters containing more than 15% contamination will not be collected.
Education and outreach are performed and once the contamination has been removed the dumpster
is collected. Recent data provided a clear indicator that multifamily and Denton Independent
School District (DISD) properties are a high source of contamination.
In response to the commercial contamination, SWR has implemented three pilot programs to
reduce contamination. SWR created a multifamily-only pilot route to narrow in on where the
contamination is occurring. The second pilot program was a DISD only route to narrow in on if a
significant amount of contamination was occurring there. These two test routes did identify that a
15%
27%24%25%
16%14%
8%
21%25%
13%
33%
0%
10%
20%
30%
40%
1311 1414 1511 1211 1314 1411 1514 1217 1316 1417 1516
% of Tags per Route
Percentage of Tags
134
177 160 154
186
216
170 150
191
111 134
20 47 39 39 30 30 14 32 47
14
44
0
50
100
150
200
250
1311 1414 1511 1211 1314 1411 1514 1217 1316 1417 1516
Audits and Tags per Route
Audits Contamination Tag
Date: 1/28/2022 Report No. 2022-009
significant amount of contamination was occurring with these two types of customers. As a result
of that data, we started a third pilot program of implementing restrictive lids and a locking bar to
prevent large bulk items and recycling contamination from entering the recycling stream. In
December the pilot program has shown promising results including an increase in net tons and a
decrease in contamination. The pilot will be complete by the end of January and the next step will
be identified.
This information will be used to create focused education and outreach to specific sectors of our
commercial customer base.
CONCLUSION:
With the current rate of contamination, Solid Waste and Public Outreach will continue to partner
and follow the below action plan to help reduce the contamination rate. Our approach is outlined
with a 4 step process.
1. Identify the highest contamination routes
a. Data collected and analyzed
b. Heat Map creation to help narrow in on areas with the most concentration of high
percentages
2. Identify top items causing contamination
a. Utilize new software Rubicon to identify contamination items and frequent
offenders
b. Work with Vendor Partner Pratt to identify contamination items/reasons
3. Utilize current education tools to target routes and items causing contamination
Date: 1/28/2022 Report No. 2022-009
a. Direct Mail
b. Contact HOAs
c. Social Media
d. Recycling Audits
4. Analyze implemented solutions
a. Create a best practice
b. Repeat Steps 1-3 each month
STAFF CONTACT:
Brian Boerner, Solid Waste Director, Tammy Clausing, Businesses Services Manager, Solid
Waste and Recycling