4d - CR&R Diversion Estimation Report
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Costa Mesa Sanitary District
….an Independent Special District
Memorandum
To: Board of Directors
Via: Scott Carroll, General Manager
From: Javier Ochiqui, Management Analyst
Date: November 12, 2013
Subject: CR&R Diversion Estimation Report
Summary
On May 23, 2013, the Board of Directors received the CR&R, Inc., Environmental
Services (CR&R) performance audit results and directed staff to implement the
recommendations that were cited in the final audit report. One of the
recommendations was to establish a more defensible waste diversion methodology.
While the CRT Material Recovery Facility (MRF) has substantiated all diversion claims,
the consultant believed that improvements to the “front-end” characterization model
were needed. Staff is providing the Board of Directors with the improved methodology
for estimating the diversion of waste from CMSD and processed by CR&R.
Staff Recommendation
That the Board of Directors accept the new diversion methodology and require
CR&R to use this method in all future sorts.
Analysis
During the process of auditing CR&R, the consultant noted several potential
deficiencies in the methodology employed by CR&R in developing waste diversion
estimates. However, there were many valuable components with the previous
methodology, so this revised methodology was performed to fine-tune the areas that
may potentially be deemed deficient by future or State auditors. The following areas
were deemed problematic with regard to the current diversion estimates:
Board of Directors
November 12, 2013
Page 2 of 4
• Justification of route areas chosen for sampling has not been supported by any
demographic data.
• Existing methodology only established recycled material composition and did
not address how facility diversion capabilities were incorporated into
establishing what is recycled versus what is disposed.
• No characterization was performed on non-recycled material thus the
composition of disposed wastes is unknown.
• Sample sizes (average of approximately 250 pounds) of 1% to 2% of full vehicle
loads may be too small to provide an accurate representation of material
composition.
In order to address these areas, the following steps in the methodology process were
implemented (Attachment 1):
1. Validation of Sample Collection Areas
2. Diversion Estimation Methodology
3. Sample Sorting Results
4. Recommended Procedures
Validation of Sample Collection Areas
The current 57.84% diversion rate was based on a January 2011 sampling. The first
step is to select collection routes that provide a representative sample of that day’s
overall collection activity. We used census data to establish and examine “quadrants”
within each service-day area to access the reasonableness and accuracy of CR&R’s
previous selections. The consultant was able to access detailed demographic data
that breaks down each area into 15 to 25 smaller areas to reflect their own unique
demographic mix.
Diversion Estimation Methodology
The previous waste diversion methodology did not provide a clear approach on how to
approximate the effectiveness of actual sorting operations. This “approximation” is
believed to be required should a third-party (such as CalRecycle) attempt to verify
diversion rate claims. The consultant also believed that a 1.17% sample size of the
total waste collected could be considered inadequate by a third-party auditor.
Since then, CR&R, CMSD, and the consultant yielded a new methodology that is more
detailed and defensible. The new method consisted of two sample sorts. For the first
sort, we utilized a large bucket-loader to mix an entire truckload (sample route for
Tuesday collection) and to subsequently “scoop” the portion to be sorted. The total
weight collected was 9.36 tons or 18,720 pounds. The sample separated weighed
3,913 pounds and represented 20.9% of the truckload (Attachment 1, pg. 14). This
provided a sample size approximately 18 times larger than the previous methodology.
Board of Directors
November 12, 2013
Page 3 of 4
The second sort occurred on a Thursday using the same process but with a smaller
bucket-loader truck. A scoop was taken from the mixed pile and sorted. The smaller
scoop weighing 1,249.66 pounds. This represented 6.26% of the 19,960 pounds
collected on the sample route. This provided a sample size that was approximately 5
times larger than the previous methodology of approximately 1%.
Sample Sorting Results
Two detailed sample sorts from material collected from CMSD were conducted. The
two days that were selected that most represented the District waste characterization
as a whole was the Tuesday and Thursday residential routes. Day one took
approximately 2 ½ hours for set-up and instruction, and 4 ½ hours for sorting. The
diversion rate for the first sort was 57.21% (Attachment 1, pg. 20).
Day two produced a similar diversion rate form a much smaller sample size. However,
sort two produced significantly more grass clippings. The diversion rate for the second
sort was 56.95% (Attachment 1, pg. 23). Based upon the sample sorts, we believe
that a 57% diversion rate is likely for the route areas sampled.
Recommended Procedures
This study provides a better waste diversion estimation methodology than the previous
approach and CMSD should consider requiring its use by CR&R in all future sorts.
Regarding route selection for sampling, we believe establishing unit-type percentages
(single-family vs. multi-family) is needed to definitively establish the appropriateness of
sample route selection. The system we used herein is an acceptable alternate, which
suggests that the continued use of historic sample areas is accurate.
Regarding sample sizes we recommend a minimum of 1,000 pounds, which was
easily exceeded by the small bucket-loader. As discussed, a larger sample size
provides better substantiation so use of the large bucket-loader would be preferred to
obtain a better representative sampling of material types.
The methodology used for this sort is considered an improvement over the historical
sorting methodology with regard to substantiating what is diverted and tying those
estimates to facility capabilities. The only improvement we suggest is to perform a
waste characterization on post-sort disposal at the MRF. The resulting waste
composition would be compared to material manifest data to fine-tune the diversion
assumptions for mechanical sorting contained in our methodology.
Strategic Plan Element & Goal
This item complies the with objective and strategy of Strategic Element 2.0, Solid
Waste, which states:
“Objective: Our objective is to manage the collection and recycling of residential trash
in the most economical and environmentally friendly way.”
Board of Directors
November 12, 2013
Page 4 of 4
“Strategy: We will do this by looking for ways to improve efficiencies, achieve high
customer satisfaction, and considering prudent new recycling methods.”
Legal Review
Not applicable at this time.
Environmental Review
Subject activity is exempt from the requirements of the California Environmental
Quality Act (CEQA) (Public Resources Code Section 21000 et. seq.). Section 15300.4
of CEQA allows an agency while establishing its own procedures “to list those specific
activities which fall within each of the exempt classes”, and the District has adopted
“CEQA Guidelines and Implementing Procedures” that state on page 6 “”Projects”
does not include …. C. Continuing administrative or maintenance activities.”
Financial Review
Since this waste characterization study provides a better waste diversion estimation
methodology than the previous approach, CMSD will most likely avoid costly waste
characterization audits and/or reviews should the State challenge waste diversion
claims.
Public Notice Process
Copies of this report are on file and will be included with the complete agenda packet
for the November 12, 2013 Board of Directors Study Session meeting at District
Headquarters and posted on the District’s website.
Attachments
1 – CR&R Diversion Estimation Report (prepared by Michael Balliet Consulting, LLC)
CR&R Diversion Estimation Report
July - September 2013
September 20, 2013
Prepared for the Costa Mesa Sanitary District by
Michael Balliet Consulting, LLC
Attachment 1
2
TABLE OF CONTENTS
Executive Summary ................................................................................................... 3
Validation of Sample Collection Areas .................................................................... 4
Diversion Estimation Methodology ......................................................................... 14
Sample Sorting Results ............................................................................................ 19
Recommended Procedures ...................................................................................... 47
Attachment 1
3
Executive Summary
Michael Balliet Consulting (MBC) was retained by the Costa Mesa Sanitary District (CMSD) to
establish a more comprehensive methodology for estimating the diversion of waste from CMSD
franchised areas collected and processed by CR&R/Costa Mesa Disposal (CR&R). The purpose
of this review was to address potential issues identified in the previous audit of CR&R and
develop methodologies that are more defensible to audit by State and County enforcement
agencies. Though no such third-party audits are currently utilized by State enforcement agencies
the CMSD believes a pro-active approach in this area is advisable.
Our previous audit of CR&R’s compliance with franchise agreement terms identified the
following areas as potentially problematic with regards to current diversion estimates:
• Justification of route areas chosen for sampling hasn’t been supported by any
demographic data.
• Existing methodology only established recycled material composition and does not
address how facility diversion capabilities were incorporated into establishing what is
recycled versus what is disposed.
• No characterization was performed on non-recycled material thus the composition of
disposed wastes is unknown.
• Sample sizes (average of approximately 250 pounds) of 1% to 2% of full vehicle loads
may be too small to provide an accurate representation of material composition.
Within the following sections of this report we address each potentially problematic area.
Therein we establish a preferred new methodology and resulting data, or suggest an alternate
methodology that the CMSD and CR&R should strongly consider adopting.
Based upon the methodology developed we established diversion rates of 57.21% and 56.95%
for the two samples that encompassed this study.
Michael Balliet
Project Consultant
Attachment 1
4
1. Validation of Sample Collection Areas
Through discussions with CR&R staff we established that the current 57.84% diversion rate
figure (City of Costa Mesa portion of CMSD franchise) is based upon a January 2011 sampling.
The first step of the existing methodology is selecting collection routes that provide a
representative sample of that day’s overall collection activity. Herein we use census data to
examine “quadrants” within each service-day area to assess the reasonableness and
appropriateness of CR&R’s historic selections.
The map below shows the various collection days and corresponding collection areas. The
consultant was able to access detailed demographic data that actually breaks each collection area
into 15 to 25 smaller areas that reflect their own unique demographic mix. Herein we refer to
those smaller areas as “quadrants”:
In order to assess the appropriateness of CR&R’s selected “quadrants” we use census data and
make the following assumptions: First, that single-family households with the highest median
household incomes represent the “most favorable” sample area (containing a high percentage of
recyclables). Second, multi-family households with the lowest median household incomes
present the “least favorable” sample areas. Therefore the “ideal” or most appropriate area to be
selected for sample sorting would be at or near the average of demographic levels that most
closely mirror the collection area as a whole.
Attachment 1
5
Both historically and currently CR&R is not required to track and report the percentages of
single-family detached homes versus the multi-family properties they collect on a given route.
Such detailed data could be “mined” from CR&R’s cart tracking data, but would require the
purchase of Geocoding software and/or extensive man-hours to apportion carts and unit types to
single versus multi-family collections on each route. Requiring CR&R to undertake this
additional cost would likely require negotiation. However, as shown herein, this type of detailed
route composition data would be helpful in determining the appropriateness of selected sampling
areas.
For our purposes herein we must establish a reasonable percentage that approximates the multi-
family unit composition of residential franchise routes, since all properties with 5 or more units
are part of a separate City-controlled franchise. The demographic data used herein makes no
differentiation of multi-family unit types in “quadrant” totals. To account for non-franchised
units we will estimate half the multi-family units established by census data as being within the
City-controlled franchise. We believe this is a reasonable estimation methodology that is not
likely to overstate the multi-family units collected by CR&R under the residential franchise.
Attachment 1
6
Shown below is our detailed analysis of census data for the quadrants that make up Monday
collections:
The areas shaded in green (quadrants “A” and “I”) contain the sample route areas selected by
CR&R to quantify recyclable material composition for their Monday collections. As shown
above these areas contain the two highest per-capita incomes within the 18 quadrants that make
up Monday’s collections. Both selected quadrants are also believed to contain a significantly
higher concentration of single-family homes (91.50% and 65.90%) than is the average for the
area (29.29%).
Based upon our analysis quadrant “F” appears to be the most representative area for selection.
This “quadrant” is an area bordered by Wilson Street to the North, Placentia Avenue to the West,
Victoria Street to the South, and Harbor Boulevard to the East. This quadrant contains both
single-family unit percentages and median household incomes that, in tandem, most closely
mirror the area as a whole.
As discussed, we would need unit type data at route and service day level to determine the actual
percentages of single and multi-family units currently sampled for the “Monday” area and as a
whole. While our quadrant specific data provides a strong indication, as you will see on the
following page, CR&R’s actual collections encompass a service area that is smaller that a
Attachment 1
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quadrant. In some cases the area selected by CR&R contains small portions of two quadrants, so
route specific data is needed to improve the accuracy of our assessment.
Quadrant “A” is bordered on the East by Continental Avenue and includes areas South of
Victoria. Everything East of Continental Avenue is within quadrant “I”. Therefore the sample
area selected by CR&R includes collections from both quadrants. While it appears this selection
includes too many higher income single-family homes, actual route data might show a more
reasonable representation. The CMSD should request more detailed route data so that a final
determination can be made. Based upon our analysis of the Monday service area appropriate
collection area should include 40%+ multi-family units and reflect a median household income
in the $55,000 to $65,000 range.
Attachment 1
8
At this juncture it is important to note that quadrant designations used herein are random letters
assigned by the consultant, based upon the order that map based census data (found at www.city-
data.com/city/Costa-Mesa-California.html ) was extricated and input into the spreadsheet used to
perform our analysis. We recommend that the CMSD and CR&R use the same map and establish
a shared and uniform quadrant identification system.
CR&R’s Tuesday collections show some of the largest variations with regards to the
demographic data we use to assess reasonableness. Quadrants on the West-side of Newport
Boulevard have some of the lowest median household incomes in the City, while the Eastside
has some of the highest.
The following page shows the area selected by CR&R for sampling. It is entirely contained
within quadrant “F” which presents both median household incomes and occurrence of single-
family homes that is above the average for Tuesday collections. Census data suggests quadrant
“I” may be a more appropriate area for route sampling.
Attachment 1
9
The portion of quadrant “F” selected by CR&R appears to have a high concentration of single-
family homes. As discussed, we believe quadrant “I” may be more appropriate.
Quadrant “I” is bordered on the West by Newport Boulevard, on the South by East 17th Street, on
the East by Orange Avenue, and on the North by East 19th Street. The projected percentage
breakdown of single versus multi-family units should run about 75/25 in the sampling area to
account for apartment complexes that are under the City-franchise.
While it appears quadrant “I” could supply a more representative sample as a whole, at the route
level quadrant “F” could prove to be a reasonable selection and is acceptable for route sampling.
Attachment 1
10
Thursday collections include the most affluent area in our study of collection days. It is
contained by the City’s Western border and properties north of Fairview Park, the City’s golf
complex, and Adams Avenue to the South. The 405 Freeway and Conway Avenue (east of
Harbor Blvd.) provide the boundary to the North, and Fairview Street provides the eastern
border.
The demographic data provided by our review, and the area selected by CR&R for sampling is
provided below:
CR&R’s selection for Thursday route sampling goes well below the area’s norm for both median
household income and percentage of single-family homes. When combined with their Monday
and Tuesday sample areas, Thursday’s composition helps bring their historic sampling more in
line with the City as a whole.
If the CMSD and CR&R bring Monday and Tuesday’s sample selection quadrants more in-line
with that area as a whole, then Thursday’s quadrant should be shifted to a more representative
area like quadrant “C”.
Shown on the following page is the portion of quadrant “G” used by CR&R for route samples.
This area has a significant amount of multi-family properties. Again, we would like to see
detailed unit-type data for this and all franchise collection areas so that we could definitively
establish the appropriateness of route selection for waste diversion sampling.
Attachment 1
11
The following section provides Wednesday and Friday collection demographic data and
establishes both “Citywide” and historic CR&R sampling demographics.
Attachment 1
Attachment 1
13
From our analysis of Census data the residential franchise produces a median household income
of $65,541.48, which is believed to be accurate for use in targeting quadrants only. The actual
median household income collected by CR&R is believed to be higher as larger multi-family
units, collected under the City-controlled franchise are included in median income. With respect
to single and multi-family distribution, using the methodology described we believe
approximately 75% of the residential franchise as a whole is comprised of single-family units.
CR&R’s route sampling quadrants and averages are shown in the table below:
On the whole CR&R’s historic sampling areas can be concluded to provide a reasonable and
appropriate grouping of quadrant data that is representative of the franchise area as a whole.
While the single-family composition and median household incomes are slightly higher than the
City average, they are not considered unreasonably high.
Recommendation: As discussed throughout this section, more detailed and specific route data
is needed to provide an unassailable methodology. The study provided herein is considered
sufficient to address reasonably expected inquiries into route selection by third parties. While we
have concluded that the existing methodology is acceptable we recommend that unit-type
collection data, for the franchise as a whole and areas selected for route diversion studies, be
assembled and incorporated into a new sample selection methodology report. We also
recommend that the quadrant system and Census data used herein be incorporated.
Attachment 1
14
2. Diversion Estimation Methodology
The previous audit concluded that CR&R’s waste diversion methodology could be considered
inadequate as it only established material composition and did not provide a clear approach used
to approximate the effectiveness of actual sorting operations. This “approximation of sorting
capabilities” is believed to be necessary should a third-party (such as CalRecycle) attempt to
verify diversion rate claims. We also believed sample sizes of only 1.17% of total waste
collected could be considered inadequate by a third-party reviewer.
Over the course of several weeks, meetings with CR&R management and staff yielded a new
methodology which the auditor believes provides the foundation for more defensible diversion
numbers going forward. The components of this new methodology are discussed by area of
concern below:
Sample Size Adequacy
Two sample sorts were approved and conducted as part of this project. For the first we utilized a
large bucket-loader to mix an entire truckload (sample route for Tuesday collection) and to
subsequently “scoop” the portion to be sorted. The photos below show the entire load that was
dumped and the portion removed for sorting by the large bucket-loader:
The total weight collected (Ticket #1865128 –
Tuesday, September 10th) was 9.36 tons or
18,720 pounds.
The sample size separated by the large bucket-
loader weighted 3,913 pounds and represented
20.9% of that truckload. This provided a sample
size that was approximately 18 times larger than
the historic methodology. The resulting “sort
pile” is shown on the right:
Attachment 1
15
The second sorting event occurred on Tuesday, September 12th. The same process was used. An
entire truckload was dumped in the sorting area (Ticket # 1866045 – 9.98 tons) then mixed by a
smaller bucket-loader (shown below - left). A scoop was then taken from the mixed pile and
segregated for sorting (shown below – right).
The smaller bucket-loader produced a “scoop” weighing 1,249.66 pounds. This represented
6.26% of the 19,960 pounds collected on the sample route. This sample size was approximately 5
times larger than the historic methodology provides.
It is our opinion that the larger the sample size the more
defensible it is with regards to subsequent challenges of
“estimation” accuracy. At 5 to 18 times the size of
samples historically used we believe both sorts provide
an improved methodology.
Sample Sorting Methodology
While it is difficult to approximate all diversion
capabilities of the CR&R’s MRF system, the materials
that are typically hand-sorted and the contamination
levels that render materials non-recyclable are not. With
this in mind our overall sorting methodology was to
remove larger items from the sorting pile to
approximate separation the internal “tommel-based”
system provides.
Sorting efforts began by removing “clean” cardboard,
mixed paper, plastics, CA redemption value containers,
and other material types that would be separated
through manual sorting at the MRF. We started with
“clean” materials so the auditor and CR&R staff could
inspect segregated materials and remove items that
were deem too contaminated. This step insures the
Attachment 1
16
validity of our methodology’s “diverted” material claims. It also facilitates our ability to
correctly identify material types within the “disposed” waste stream.
During the process of segregating “clean materials” we also segregated contaminated or disposed
items by material type. Contaminated paper products (cardboard and mixed paper) and
contaminated plastics (including non-recycled plastic bags) were two such categories to be
recorded under “disposal”.
Due to the volume of material our separation of green waste focused on “clean” material that was
greater than 6 inches in size. The photos below show our segregated materials from sort #1:
The resulting containers for mixed paper and cardboard are shown above. The items contained
therein represent what would be hand-sorted by CR&R personnel as a component of MRF
separation. These hand-sort materials would also include all California Redemption Value
(CRV) containers, HDPE plastics, mixed plastics, wood and larger green waste materials,
miscellaneous ferrous and non-ferrous metals, and concrete and other inert wastes.
Our segregation of larger contaminated materials also approximates the hand-sorting process as
these materials are not removed and travel to the end of the sorting “belt” where they dump into
a pile of materials for landfill disposal.
Attachment 1
17
After our hand sorting process removed the large items the remaining material closely
approximates the portion of franchise waste that is segregated by mechanical process. The photos
below show the composition of this material:
Of the 3,913 pounds sorted, 2,240 pounds was deemed too be processed by mechanical sorting.
This material was subsequently sorted for composition and compared to facility diversion and
disposal records to provide a reasonable estimate of what mechanical separation is able to divert.
The need for this “facility based” diversion estimation is due to the following:
1. There is no way a hand sort can reasonably approximate a trommel that segregates and
removes the majority of 2” minus material. Efforts to hand-sort materials between 2” and
6” are considered ineffective as the only material reasonably diverted in this size
category is green waste. The great majority of paper and plastic items in this size “mix”
are disposed, though some are recovered through “forced air” separation.
2. The preferred option of sampling post-sort materials for composition was not available to
us. When this composition is compared to material manifests for the entire facility, more
precise figures for material specific diversion are available.
To provide some hand-sort based data for this estimation process we employed a “clean green”
separation step. Sorters removed larger green waste material that would be removed by hand
Attachment 1
18
separation at the MRF. This resulted in 500 pounds of
material we can reasonably assume is removed from
other green waste (contained in the 2,240 pounds of
material deemed too small for hand sorting). Therefore
for our estimation purposes herein we established that
roughly 20% of the green waste processed at the MRF is
manually removed larger material as shown in the photo
(right).
Smaller pieces of green waste were found on
contaminated paper and plastic to some degree. However
the majority of this material was contained in a mix of
materials estimated in our 6” minus pile. Therefore our
estimation methodology must account for green waste
material that is greater than 2” minus which is removed
for hand sorting by mechanical process at the MRF.
To account for this material we took a representative
sample of our post hand-sort material to determine what
percentage was green waste between 2” and 6” in size.
This sample sorting pile is shown below-right.
From that point we segregated the material into
green waste, food waste, plastic, paper, glass,
metal, concrete, wood, textiles, and “undefined
fines” that compose the major material types
found therein. Within green waste we further
segregated the material by greater or less than 2”
minus, with 30% residing in the “fines” category.
The resulting composition percentages were
established for minus 6” materials:
Attachment 1
19
3. Sample Sorting Results
As discussed we were provided the opportunity to
perform two detailed sorts of material collected
for CMSD franchise areas. Listed below is the
relative truck and route information corresponding
to each sort. Also provided is the “quadrant” that
was selected for sorting by CR&R:
Date: 9-10-2013
Truck #: 57256
Route: Tuesday, Residential Franchise
Ticket #: 1865128
Date: 9-12-2013
Truck #: 57254
Route: Thursday, Residential Franchise
Ticket #: 1866045
Shown at right is a picture of truck 57256 at the
scale house (top), then (right) as it prepared to
dump materials for our waste-sort.
The sorting area provided by CR&R and truck
57256 offloading at the sorting area is shown
below:
Day one sorting took approximately 2 ½ hours for set-up and instruction, and 4 ½ hours for
sorting. The following table shows the results of this sort:
Attachment 1
20
As shown above our sorting methodology produced an estimated diversion rate of 57.21%,
which suggests the previously used methodology has provided a reasonable result. As noted the
diversion rate for non-sorted materials uses a “MRF-system ” based estimator. In large part it is
based upon “master manifest” data previously obtained during an audit of MRF records. Also
included in this estimation is the auditor’s familiarity with similar MRF system operations and
recovery capabilities, combined with my observations of proprietary systems at the Stanton MRF
during my facility tour. Therefore I am reasonably confident of its accuracy as a diversion
“predictor” herein.
As noted there are additional steps that could increase the confidence level of diversion
estimates. However those were not available for this process.
Attachment 1
21
There are several things to note within Sort #1 data. First, the disposed amounts for both paper
and plastics contain a significant amount of food waste and liquids. This is especially true for
plastics discards and we estimate that half of your Food Waste generation is contained within the
“Disposed” plastics total. Since our purpose was to establish a diversion rate, and all materials
involved are considered disposed, further separation was not conducted. Based upon our
observation of sorted materials we estimate that a minimum of 9% of residential disposal is Food
Waste. The actual figure may be higher. The CMSD may wish to perform a more detailed sort of
this material to determine the viability of proposed organics diversion programs.
For hand-sorted materials the rest of the category totals are self-explanatory. As discussed,
materials that were clean and reasonably marketable are listed as “Diversion” while
contaminated materials and materials without current markets are listed as “Disposed”. The only
exception to this is the material category for “Liquids”. The 10-pound figure listed as “Diverted”
accounts for liquids found within bottles during our hand-sort. We quantify the volume of this
material and credited it as diversion herein to account for “shrinkage” as noted in the CR&R
master manifest. In our model we credit CR&R for approximately 0.26% diversion for liquids
recovered by their MRF system.
Within the mechanical separation numbers is where we utilize the master manifests, industry
knowledge, and facility specific equipment to make reasonable assumptions. Let’s examine those
assumptions and the resulting diversion and disposal figures for the items noted in our Sort #1
table. The table below shows the calculations performed to arrive at these figures:
First, for paper and plastics the MRF employs air separators to blow lighter materials like paper
and plastic from a descending stream of mixed refuse. As a result the materials included in our
minus 6” material sort contained a percentage of paper and plastic that the MRF facility actually
diverts. Therefore we estimate that 10% of the paper and plastic in our small material mix is
diverted through mechanical separation, while 90% is disposed.
For green waste we credit CR&R’s system with the capability to divert 100% of the material that
is greater than 2” minus. We also credit their MRF system with diverting 70% of the smaller
material. While I cannot disclose their proprietary systems and the specifics I utilized to establish
Attachment 1
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these percentages, the resulting green waste diversion (a 36.21% component of the entire Sort #1
load) matches closely with the 37.88% figure supported by their master manifest data.
For mechanical diversion of glass I am giving CR&R’s MRF system credit for diverting 10% to
account for intact containers missed by the hand sort and the capacity of this system to recover a
percentage of glass “breakage”. Including our hand and mechanical diversion Sort #1 data
matches up exactly to the master manifest percentage for glass diversion (1.81%).
With respect to metals diversion the use of magnets in the mechanical separation process is an
industry standard. I am estimating an 80% recovery rate by the MRF’s mechanical system for the
smaller material. In combination with the 86% diversion rate credited for hand sorting I believe
this provides a very reasonable diversion figure for metals.
Finally a percentage of “Fines” is credited with diversion via the current “Trail Mix” program at
Chiquita Canyon landfill. At 5% of the total fines identified the resulting diversion closely
mirrors levels substantiated by CR&R’s master manifests.
Attachment 1
23
Sort #2 produced a similar diversion rate from a much smaller sample size. As discussed
previously we used a standard bucket-loader for this sort and the resulting “sort pile” was about
1/3rd the amount produced by the large-loader.
The hand-sort portion of Sort #2 achieved a higher diversion rate than Sort #1 (81% to 72%).
While this could be attributable to the small sample size we believe it is due to a better sample
route. Supporting this assumption is the higher percentage of diverted cardboard/paper (19.0% to
10.2%) and CA redemption containers (6.7% to 2.3%) accounted for in our total sort
composition. Sort #2 was definitely higher in high-value recyclable material content.
The route selected for Sort #2 also produced significantly more grass clippings. However, this
did not equate to a higher percentage of smaller “mechanical sort” waste (50% in sort #2 versus
57% in sort #1). The table below shows our estimation process for smaller material diversion:
Attachment 1
24
We believe that the “Fines” total above includes a larger amount of green waste than Sort #1, as
evidenced by the lower (33% versus 36%) percentage green waste diversion accounts for in our
Sort #2 composition (more is included in disposed fines). However, the methodology used above
was established by a viable methodology and reconciled to master manifest data. Therefore it is
considered reasonably accurate and not appropriate to adjust from load to load. In addition we
believe green waste “fines” (2” to 6”) are represented accurately herein. Green waste in the 2”
minus category is where the higher percentages occur, due to a large amount of grass clippings in
this load. The consultant believes difficulties in diverting this material from mixed waste is fairly
approximated in the data above.
Summary: Based upon our sample sorting we believe a 57% diversion rate is likely for the
route areas sampled.
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4. Recommended Procedures
We believe this study provides a better waste diversion estimation methodology than the
previous approach and the CMSD should consider requiring its use by CR&R in all future sorts.
Regarding route selection for sampling we believe establishing unit-type percentages (single-
family vs. multi-family) is needed to definitively establish the appropriateness of sample route
selection. The system we used herein is an acceptable alternate, which suggests the continued use
of historic sample areas is accurate.
Regarding sample sizes we recommend a minimum of 1,000 pounds, which was easily exceeded
by the small bucket-loader. As discussed a larger sample size provides better substantiation so
use of the large bucket-loader would be preferred to obtain a more representative sampling of
material types.
The methodology used for this sort is considered an improvement over the historical sorting
methodology with regards to substantiating what is diverted and tying those estimates to facility
capabilities. The only improvement we suggest is to perform a waste characterization on post-
sort disposal at the MRF. The resulting waste composition would be compared to material
manifest data to fine-tune the diversion assumptions for mechanical sorting contained in our
methodology.
Attachment 1