There was something uncommon about the crumb rubber extracted from the football field being serviced last year by G9 Turf, an independent contractor that specializes in the maintenance of synthetic turf sports fields. Using a specialized machine that blasts the field surface with 150 pounds per square inch of air pressure through dozens of oscillating nozzles, the infill was loosened, lifted and steered into white bags by a screw conveyor. “We’re filling the first bag of infill, and the material is coming out purple and red, and the dust is flying everywhere, and we’re thinking to ourselves, ‘What is going on here?’ ” recalls G9 Turf president Grant Hendricks Jr.
The municipally owned field was home to multiple football teams, each with its own midfield and end zone graphics, requiring regular introduction of chalk-based paints to the turf system. Over time, the field had hardened to the point that something had to be done. “We analyzed the material, and it’s just shot. The infill is like little rocks now, because there’s so much chalk-based paint on it,” Hendricks says. “We blasted it out and then replaced it with new infill in about three days, and the field was like brand new.”
It was a situation that G9 Turf — which incorporated in 2009 as a field installer but has since settled into the maintenance niche — had never seen before. And while extreme, the paint case illustrates the need for field owners to maintain their fields on a consistent basis — not only to immediately improve a field’s playability and safety, but perhaps extend its useful life.
How soft? Hendricks says that an ideal G-max range is between 135 and 155. “Anything over 190, we consider to be in the warning zone,” he says. “We encountered one that was 218, and I had a feeling it was going to be like that. You could feel it by walking on it. It was a baseball field, and it was as if they were playing in a parking lot.”
Seven years’ worth of sun, wind and rain had caused enough clay material surrounding the field’s bases to migrate into the infill profile. “We ended up using the tines and the air,” Hendricks says. “It was so densely compacted that we had to drive the tines down into the yarns, just to loosen it up, just to get the air underneath it. But we got the G-max down to 160.”
Unlike SMG’s Dorney, G9 Turf recommends three or four deep-tine aeration sessions each year in order to avoid — or at least delay three or four years — the need for a full-depth rejuvenation using air pressure, which can require a week to complete and cost up to 10 times what a single tine aeration costs. The air-pressure technique’s advantage is that it removes infill without any mechanical contact with the field’s turf fibers. “We’ll blast the infill all the way down to the carpet backing and lower the G-max to make the field safer and more playable,” Hendricks says. “We’ve had players come out and say, ‘I can’t believe this is the same field.’ ”
Once removed, the infill can then be inspected for structural integrity and reintroduced to the field or (less commonly) replaced. G9 Turf worked on a nine-year-old field whose crumb rubber had degraded to the point of no return. “For the amount of money that you’re going to spend, you may as well introduce fresh infill that’s going to extend the life of the field another three or four or five years, instead of putting back the same dead infill, especially if it’s been broken down to the point where it’s so fine that it’s going to get densely compacted in a matter of no time,” says Hendricks, adding that G9 was called upon to salvage the infill from a new field whose fibers had exhibited failure, saving the manufacturer significant money.
When a field has reached its functional limits, G9 Turf can also be called on to separate all components of the turf system for recycling. “If they can’t be reused in another field, then the components can be separated and used in other applications — for example, roadway construction,” Hendricks says. “Nothing goes to a landfill.”
Though his company bowed out of the uber-competitive installation market, Hendricks considers all of the infill systems available today to be “varying degrees of good.”
“Everybody has their own twist, but that doesn’t affect us with regard to maintenance,” he adds. “Anything that’s out there gets compacted. Every field, regardless of the infill, needs maintenance.”
How quickly a field gets compacted will depend largely on how rigorously it is used. “There are some high schools where all they do is play football on that field, and if it’s maintained properly, it will last forever,” Hendricks says. “But then you go to New York City, where they have dozens of synthetic turf fields that get 24/7 usage, and they may only last three or four years, because they get so much traffic. Every opportunity is unique, depending on the amount of traffic and what’s actually being done on the field.”
“Most often, maintenance is determined by the amount of use a facility gets and its available resources,” Dorney says. “It differs by manufacturer. Some manufacturers recommend that a field is brushed or cleaned every 80 hours of use, but some owners, if they have a tow-behind unit, are out there cleaning it before every football game.”
How much can field owners expect to invest in the upkeep of their initial six-figure synthetic turf investment? SMG’s SportChamp, which is employed by field owners, manufacturers and contractors alike, costs roughly $45,000 with three front attachments and a rear leveling brush. (Up to 15 attachments, including everything from metal-gathering magnets to snow-removing plows and blowers, are available.) And while the nearest NFL franchise to Dorney doesn’t own a SportChamp, each of the Seattle area’s largest school districts — with multiple fields to maintain — does.
For those who choose to contract with a maintenance service provider, Hendricks says field owners would be well covered by budgeting $10,000 to $15,000 annually for independent G-max testing and four or five maintenance sessions. “The return is amazing. Not only is the field going to last longer, but it’s going to be safer,” he says. “Maintenance is not a big-ticket item, but it’s a critical item. You just can’t afford not to do it.”
Since hardness is a leading concern of owners and end users, a field’s G-max resiliency measure should be tested annually by an entity independent of the maintenance provider, according to Hendricks. Maintenance protocols may vary from there, depending on the contractor or equipment involved, but the end game is the same.
Auburn, Wash.-based SMG Equipment LLC is the North American distributor of German-made SMG turf maintenance equipment, ranging from tractor attachments to walk-behind and self-propelled machines. According to SMG’s Kevin Dorney, the most frequently used piece of equipment is the brush, which redistributes displaced infill and maintains proper infill depths. “Brushing will even out any irregularities — move highs to lows over a small area,” Dorney says. “It’s not going to move a high 30 feet over to a low, but it will level out the areas immediately around it. It also stands the fibers up, so there is better play characteristics for the field.” (Dorney adds that field owners should regularly measure infill depths and manually add infill to areas where extreme displacement is likely to occur — corner kick areas and goal mouths on soccer fields, or sliding areas near the bases on baseball fields, for example.)
Several times a year, the infill should be cleaned, a process completed by several pieces of SMG equipment — most notably by the self-propelled SportChamp. Infill and debris are swept onto a vibrating sieve tray, which retains the debris and returns the infill to the turf. Debris can take the form of organic material such as twigs, sunflower seed shells and pine needles, as well as man-made safety hazards such as hairpins, nails, nuts and bolts. Lighter debris is captured by the SportChamp using an onboard air-filtration system.
An aerating tine is introduced to the infill less frequently. “Typically, owners will decompact a field once a year so that it loosens the infill and makes it softer,” Dorney says.
COMPREHENSIVE MAINTENANCE OPTIONS
Comprehensive maintenance generally includes the use of specialty maintenance equipment by trained maintenance professionals. Depending upon the situation, the following actions may be performed:
- • Professional field inspection and corrective action — Assess the field surface, especially heavy-wear areas, identify weak or loose seams and inlays, and repair the damage. Sport performance testing may also be desirable.
- • Decompaction of infill — Infill decompaction is important for improving shock absorption and synthetic turf drainage. Use only equipment specially designed to decompact and create loft in infilled synthetic turf systems.
- • Redistribution and leveling of the infill — Measure infill depth on a grid pattern, and add and level infill as needed to return the surface to the field builder’s specifications.
- • Deep Cleaning — Use special equipment that combines mechanical brushing, suction and an infill-return system to remove surface debris and embedded contaminants.
- • Metal removal — Use a magnet attached to your maintenance equipment to remove ferrous metal objects from the field.
- • Weed and pest treatment — Treat with herbicides or pesticides, as required.
- • Partial removal and reinstallation of infill material — Remove the infill, as necessary, to get rid of embedded foreign matter that has contaminated the infill system, relieve grass fibers that may be trapped in the infill, or improve drainage.
Source: Synthetic Turf Council
ONGOING MAINTENANCE MUSTS
- • Conduct inspections and perform minor repairs to avoid playing hazards.
- • Keep the playing surface clean and free of debris and contaminants.
- • Check and maintain proper infill levels to provide a consistent surface.
- • Brush the surface to preserve appearance, keep grass fibers upright, and maintain even infill levels, making sure to use only approved bristles that will not overly abrade the fibers.
- • Maintain a maintenance and activity log.
Source: Synthetic Turf Council