MSW Management | Optimizing Transfer Trailer Loading Through Teamwork

SUBSCRIBE

COMMENT
ON THIS
ARTICLE

CREATE A LINK
TO THIS ARTICLE
ON YOUR SITE

Correcting an inefficient loading system can make a big difference in productivity.

By William A. Corrao

Approximately $80,000 was spent one year in avoidable transfer trailer repair costs at the Del Norte Division of Republic Services Inc. (RSI) in Oxnard, CA. This was because of imperfect systems-management of the gravity-loading method of the type of trailer found in use at most transfer stations.

We determined that we would focus a study on: 1) observing the “as-is” condition, identifying critical parameters; 2) assessing the potential for change intervention without interruption of service; and 3) implementing the reframing of the organizational structure (without adding to headcount) that would ultimately eliminate or greatly reduce collateral damage to transfer trailers.

At the outset, we observed that one trailer of the 300 loaded per week was being damaged and required repair. Average repair cost per week was $1,500.

In our assessment of the needed intervention, we found that 12 people would be required to effectively and safely load transfer trailers. These were identified as the “stakeholders” in the proposed organizational change. In our skills assessment of the individuals involved, we determined that some additional and more frequent training would be required for the group. Various training programs were developed in-house or copied from some of our RSI sister divisions.

We recognized that organizational structures are rarely optimal. Our challenge therefore was to identify the structure that best fit our current needs and then reframe the organization accordingly. This reframing would include the stakeholders mentioned above. Also determined was the need to divide the stakeholder group into two teams of six members each. Our reasoning behind this is detailed later.

A loader bucket tamps material in the trailer.

Del Norte Transfer Station
RSI owns and operates a network of transfer stations, collection companies, material recovery facilities, and landfills ensuring environmentally sound and cost-effective waste management throughout the United States. The Del Norte facility is owned by the City of Oxnard and is operated by RSI. Transfer stations serve as remote gates for landfills by enabling collection vehicles to dump their loads in close proximity to their routes and return to them quickly. Waste from four to six collection vehicles is consolidated at transfer stations and loaded into one open-top transfer trailer throughout the day for delivery to an environmentally sound landfill or incinerator.

The Del Norte facility loading area utilizes two gravity-load-out floor ports. These ports are rectangular holes in the 24-inch-thick concrete floor, measuring just less than the size of an open-top 48-foot trailer. The transfer trailers are staged on the loading ramp directly below the port openings in the subterranean “tunnel.” Approximately 23 tons of municipal solid waste is pushed through the port and into the trailer below, a distance of approximately 15 feet from the upper floor level to the trailer’s live floor below. The trash is pushed into the trailer with a Caterpillar Model 950 front-end loader. In order to maximize payload, the loader’s bucket is used to reach down and into the trailer below to tamp down the material once it is dropped through the port. The waste, particularly when it is right off the tipping floor, is “fluffy” and needs to be “densified.” To facilitate that, each loader is equipped with a flat-bottom scoop bucket.

The trailers, on queue below, park on a set of truck scales. The loader-operator watches a weight indicator suspended from the transfer station ceiling directly above each port. Each tractor-trailer is rated for an 80,000-pound gross vehicular weight, and we ensure that each transfer load is at maximum capacity for the 75-mile round trip to the landfill. The loader-operator also has the responsibility to sort and pick any recyclable material, potentially damaging heavyweight material, or oversize material from the waste pile during the “prepping” process before pushing it into the trailer. Prepping the pile usually constitutes staging the material to be loaded away from the port and rolling it forward several times to check for unwanted material (e.g., oversized items, heavy items, recyclable materials, or even such dangerous materials as unemptied propane tanks).

Each operator is teamed with a floor spotter to assist in prepping the pile. The loading process is usually done in three or four sweeps of the bucket along the length of the port. Each sweep deposits approximately 5–8 tons of material evenly from the front to the back of the entire trailer. With each sweep of the bucket, the floor spotter positioned above the trailer on the main floor will work the deposited material by knocking down any vertically extended material, thus leveling the load further. Using a 15-foot, specially designed rake, the floor spotter removes any unwanted material. The rake is fashioned with a hook on its business end for pulling or pushing material. The floor spotter also warns the operator of any potentially damaging material that is being advanced toward the port. Previous to this intervention, the warnings were in the form of simple hand signals.

Also involved in the process is another employee referred to as a dispatcher. The dispatcher works generally and more closely with the transfer trailer driver staged in the tunnel. The dispatcher and driver use a remotely operated, red-light/green-light signal located in the tunnel. They also have the advantage of two-way radio communication for the purpose of queuing up and then releasing the truck when loaded. Previous to this intervention, there was no two-way radio communication between the dispatcher, floor spotters, public support personnel, or supervisors.

Even though the dispatcher had an overview of the working area from a second floor glassed-in observation office, he had almost no control over the floor processes or worker movements. The only communication the dispatcher had with the loader operator was through a two-way radio in order to signal that a trailer was ready to be loaded in the tunnel below.

Rounding out the loading-area personnel were four to six public support employees. Public support employees, working behind the floor spotters and away from the ports, are not directly involved in the loading process or floor spotting functions, but while working in their capacity of assisting outside customers in off-loading their waste, the public support employees would keep a watchful eye for potentially damaging or dangerous material that might make its way to the gravity-loading ports nearby. In this original configuration, there would 11–13 workers engaged in a relatively large area without a sense of teamwork, accountability, or indirect communication, either electronically or face-to-face.

Proper procedures in tight-quarter operations reduce mishaps.

In late 2003, as a part of this study, we assessed the equipment repair budget. We felt that it was an excessive yet controllable expense that had to be investigated immediately. Over the course of time, a cultural division apparently had evolved in which the loader-operators were not following the warnings of the floor spotters. Higher-paid operators literally ignored the lower-paid employees’ directions and assumed total control of the loading operation. This unfortunate practice appeared to go unnoticed at the time, as no action to change the behavior was evident. When significant damage to a trailer occurred (approximately one trailer per week) it would be delivered to the onsite maintenance shop for repair. The corrective work would then be completed, paperwork submitted to the contractor’s billing department, and an invoice sent to Del Norte division management for payment. The bills would typically be paid without much investigation or significant inquiry; the accuracy was difficult to verify because the incident usually occurred weeks earlier. Currently, rarely occurring damage is noted on dispatch reports immediately and photos are taken. The transfer station supervisor conducts a meeting with the load team deemed responsible even before releasing the trailer to the maintenance shop for repairs.

Typical Trailer Damage
Trailer repairs included replacement of torn aluminum sidewalls; broken, cracked, and/or crunched live floor extrusions; undercarriage crossbeams; and other structural members inherent in transfer-trailer design. The damage was usually similar in nature and easily traced to its root cause being that something extremely heavy was obviously dropped 15 feet into the trailer below. These unnoticed objects, including tree trunks and engine blocks, were either not seen or else ignored in the prepping stage. Also, while tamping down the trash, an oversized or sideways-facing bulky object could be pushed through the sidewall. Trailers were also inspected and photographed to record the normal wear and tear on a transfer trailer to differentiate it from damage sustained in the loading process.

Methodology
Inability to perform what we call an “integral loading transaction”—that is, loading and conveying trash to a landfill without damaging the equipment—can negatively affect the way we are viewed. When the damage problem was first brought to the operations manager’s attention, the first reaction was to just push the problem resolution down the chain of command. However, we realized that handling the potential organizational reframing of the loading process “scientifically” could result in our staff gaining a valuable learning experience. We would also benefit by the establishment of a new teamwork culture in the workplace. At that, the entire staff went into full organizational-change mode. We began to realize how much this type of inefficiency affected the operation. We decided that the goal would be to develop a written procedure along with team accountability in order to ensure that this problem would never happen again. Conversely, if all went well, there would be rewards for a job well done.

In discussing the needed management and operational structure we found that two supervisors, two dispatchers, the operations manager, six front-loader operators, four floor spotters/rakers, six public support personnel, the division controller, and the general manager would all have a stake in this organizational change process.

Other staffers were not directly involved, although they were kept in the loop through staff meeting updates and open discussion.

Of these 23 people, 12 would be directly involved with actual loading operation. They were divided into two loading teams of six each. However, dividing them into two teams went beyond being able to create competition or to encourage finger pointing.

Work schedules were established where these team members would always be working together, which would enable Team A to attend foreseeable team meetings while Team B facilitated the loading process, and vice versa.

Teamwork is vital to your operation’s success.

Results and Conclusions
The following data indicate improvements over the 18-month period.

The production metrics and operational ratios captured on a newly created dispatch report were analyzed to measure anticipated improvement in average loading times, deviations from the average, notations of damage, and efficiency in the staging position. They also ensured that we didn’t unwittingly lengthen our loading times while working to eliminate damage to transfer-trailers. We installed this check in the event we inadvertently slowed the loading queue to prevent damage so much so that we would lose productivity at a lopsided rate.

After an intense, 18-month intervention and study, transfer-trailer collateral damage experienced in the loading queue had been reduced by 88%. More significant than our initial goal, however, was the astounding increase in production, as reflected in a reduction in loading time from nine minutes to seven minutes, as well as a much narrower deviation-from-average loading time bandwidth.

This showed that we were operating more efficiently and consistently, enabling us to increase our daily outbound tonnage significantly. New methods of operating the Cat 950 loaders resulted in a 10% reduction in fuel costs.

The performance ethic has greatly improved. Communication is facilitated by means of two-way Motorola radios now in all 12 team members’ hands.

Here at Del Norte, we discovered a new culture in that a team that outperforms all other like teams by an order of magnitude (in this example, a desire for excellence) as well as outperforming all reasonable expectations is identifiable by its results and by the individual members’ commitment to one another.

Team members are more confident in their work, speak up more at team meetings, and raise safety issues knowing that they will be heard and that they are empowered to make this an excellent and safe place to be.

William A. Corrao, M.A., is general manager for the Del Norte Division in Oxnard, CA.

MSW - May/June 2007