Hydroseeding Moves Up

March 1, 2011

Although few people are browsing yacht catalogs in today’s tough economy, most erosion control firms remain busy at work, thanks to the critical nature of their projects. Soil must be retained at all costs; common sense, as well as state and federal regulations, demands it. Because of its efficiencies—powerful machines that require smaller crews and that can apply seed, mulch, and other ingredients in one fell swoop—hydroseeding may be uniquely poised to benefit in today’s economic climate.

Post-Application, Water Remains a Problem
Hydroseeding provides the advantage of including life-giving water to seed, but after that, seeds are pretty much on their own. “We rely so much on Mother Nature for our watering,” says Ryan Clark, hydroseeding manager for J&C Environmental Services in Marlow, OK. “Sometimes we get an overabundance of rain, which makes us look good. Other times, conditions are drought-like. Due to this, using a good product is essential to keep what you’ve installed in place.”

An estimated 95% of Clark’s work is for the oil and gas industry. “The industry just wants to solve erosion. However, since its sites are often in someone’s backyard, I have to deal with residents, and I want them to be happy. Therefore, when seeding, I’ll ask the client if I can use a better seed mix, something nicer for residents to look at. If residents ask for wildflower mix, I’ll put it in, and generally those locations don’t get mowed. I’ll use native seeds, Bermuda grasses, whatever will grow fastest. We change mixes depending upon the seasons.”

If the site is near a wildlife refuge, different guidelines apply. “We have to abide by that site’s specifications as well, which usually include anything to promote game and fish. For example, we can’t use Bermuda grass, which takes over and doesn’t give anything back to the animal life. In game and fish areas, a concrete curb must be built around the gravel pad, along with an 8-foot chain-link fence, to keep animals out. The drillers also have to plant honeysuckle to hide the location, and any equipment has to be painted, like camouflage.”

The amount of work necessary has changed, too. “When we first started, we would go in after the gas company did a final cleanup. Now, the USEPA, and the states’ DEQs [departments of environmental quality] are very particular. When the well pad is built-they put in gravel pads-we have to hydromulch right away. Sometimes the drilling crews do so much damage while putting in a well pad that we have to go in more than once. These sites might also have a ‘reserve pit,’ which catches all the chemicals from construction and drilling; we have to hydromulch that and take photos to prove to the EPA that the work has been done. At each location a berm is put up, but then workers drive over it and tear it up. When they see exposed dirt, we have to come back. We have to redo some sites three or four times.”

Clark’s firm, which operates in Oklahoma and Arkansas, often has to traverse difficult terrain. “As the oil and gas companies have to clear out trees to make access roads, some of these locations are in the hardest possible areas to reach. In addition, Arkansas has lots of hills. When the rain season comes, despite four-wheel drive, sometimes you can’t move the trucks in very close. We’re carrying a lot of weight-the water alone weighs 8,000 pounds. Many times, we have to drag out all the hose we have just to reach the site. All our trucks carry 300 feet of hose.”

J&C Environmental Services owns four Bowie Hydro-Mulcher Victor 1100 machines. “We like them,” Clarks says. “Their positive gear pumps are capable of pushing slurry good long distances, and the machines are really heavy-duty-they work day in and day out. In the event they do need repair, you don’t need a major technician to repair one. Bowie’s 1,100-gallon machine will cover an average of 10,000 square feet, or a quarter-acre. Of course, it all depends on what we’re putting down. Sometimes we’ll apply thicker mulches, like BFMs [bonded fiber matrix].”Due to the remoteness and the size of work sites (ranging from 1 to 20 acres), Clark often has to take everything he might need with him. “We’ll carry about 180 bags of material to a location. Out in the Oklahoma panhandle, we have trouble buying water to use. Landowners use it for cattle, and we have only so much water we can carry, so one truck is designated for water. We make a convoy: the hydromulch truck, and a pickup that goes for water. Sometimes we’re allowed to take water from ponds, which costs us about $100 per day. Sometimes we can only get water from a city hydrant; that gets costly. But, if we’re way off the beaten path, there’s a 120-barrel/5,000 gallon tanker we’ll hire to bring our water for us.”

Regulations and climate sometimes clash. “To lessen the impact on the sites we work, we’d like to get high flotation tires, which won’t leave ‘footprints,’ but they’re not DOT-legal-and our trucks must be highway legal at any time. We have three three-man crews, running constantly. We need one crew on-call 24 and seven for the gas company. For example, sites might get battered with popup storms, dumping 3 to 4 inches of rain in less than an hour-yet get not even a drop a mile away. If that storm hits a freshly built location, it will nearly destroy it. That’s when we have to be on call at moment’s notice. And, although in some instances, drilling crews will return the topsoil, we’re usually dealing with subsoil, which is a problem to begin with.

Erosion, Dust, and Weed Control
Environmental Site Maintenance (ESM) of Simi Valley, CA, saves costs and time by multitasking. “We have several home builders that utilize EarthGuard fiber matrix,” says ESM president Gil Carrillo. EarthGuard is manufactured by Bakersfield, CA’s Terra Novo.

“We use EarthGuard on every Richmond American Homes site in California—on every type of terrain, from 2:1 slopes to flat lots,” he says. “We use it for erosion and sediment control. The application also keeps bad vegetation-weeds-from growing. On a typical site, we’ll use 4 gallons per acre of EarthGuard, about 1,500 pounds of wood fiber mulch, and add RoundUp Pro. We won’t add any seed mix, as the eventual home sites will like a nicer lawn. If we’re working on a slope, then yes, we’ll add a number-one control seed mix. Otherwise, flat lots just get EarthGuard and hydromulch, to keep the lots bare.”

Carrillo has used other products, but now prefers EarthGuard. “One, it’s extremely effective; we have 100% satisfied clients. Two, we get great support from Terra Novo. They totally understand their product, and can tell us what they’ve done studies on, what’s most effective and cost-effective.”

Using a Finn T330 HydroSeeder, Carrillo’s firm mixes mulch and EarthGuard to a thick, soupy, “oatmeal-like” texture. “We’ll use the hose for hard-to-reach areas, and the Finn also has a large cannon on top, which allows us to apply slurry up slopes and down embankments. The mulch we use has green dye in it; as you’re spraying you can see texture and certain color, so you know it’s covering. The next day, if you see a lighter green, you can give that area a little extra. The dye lasts only 72 hours before fading to a dirt color.

“I’m a big supporter of EarthGuard and recommend it, because of cost. It’s one-half to two-thirds the price of other means, such as blankets,” he concludes. “Plus, you don’t have to take it down; it’s biodegradable, unlike blankets. Using EarthGuard, we have a quick, easy, in-and-out job. It’s 100% effective in the applications, as long as you have an operator who does it right.”

During his 10 years in the erosion and sediment control business, Carrillo has done just about everything. “We’ve done several commercial projects, everything from public works jobs to private jobs,” he notes. “We did the LA Design Center.”

Ingredients for Better Results
There is one “problem” with hydroseeding: It works well, so sometimes application crews or clients are hesitant to make any changes to the process. The thought is, “If it ain’t broke, don’t fix it.” However, certain weather and site conditions can help those who want to improve the process to redefine “broke.”

“I’ve seen one idea catching on here,” says Carol Davis, president of Edgewood, WA’s Briargroup Inc. “After years of effort, on my part and others’, clients are beginning to accept bonded fiber matrix. Now, when we get lots of rain, clients will accept BFM upgrades; we’ve been able to get three or four change orders on projects, due to fall and winter weather and due to the slopes they’re upgrading. BFM works better than blankets or topping with straw in such conditions.

“This change is very good for the industry,” she continues. “Applying BFM lets us do our task in a shorter amount of time, and provides better utilization of our equipment. BFM also allows me to meet the client’s needs on many projects. This past fall, the supplier of our BFM product looked at one of my projects and told me it looked “˜fabulous.’ This site was a 1:1 slope, which was not originally specified for BFM. However, the site’s owners readily accepted; I just sent them information on BFM and they accepted that instead of mulch.”

BFM was introduced to the northern Pacific coast in the mid 1990s. “It’s taken a while to get acceptance here,” Davis says. “Spraying BFM makes projects more cost-effective, and the results are more successful than when using regular mulch. With mulch, we often had to return to sites for redos; BFM accomplishes what we need in one application.”

Briargroup uses Finn HydroSeeders to apply seed and BFM. Because HydroSeeders use hydraulically driven mechanical paddle agitation and liquid recirculation to enhance the loading, mixing, and discharge operation, Davis’ crews can easily add all ingredients to the HydroSeeder, and the resultant slurry will provide even coverage of seed and BFM.

“In the old days,” she says, “some projects might have also needed matting and straw on top of the hydroseeding, which, in essence, meant three erosion control applications. I don’t do straw and matting, so I’d have to bring in a subcontractor. In addition, straw has to be removed before working the site in the spring. That’s a lot of trips, and a lot of crews. Now, by using BFM, my crews can do all the work.”

A Peek at Peak Performance
Finn HydroSeeders are a definite boon to crews that work in difficult terrain. “We have several Finn machines,” says Colby Reid, reclamation division manager for Western States Reclamation in Frederick, CO. “The majority of our work is on mining sites and pipelines, although we also do wildfire reclamation and “˜standard’ DOT work. Being in Colorado, we do a lot of mountain work-all the states around here have mountains. We have three trucks with larger tires and all-wheel-drive. The trucks are six-by-sixes-with six tires-so we have a lot of traction where we’re going. We also have a smaller hydroseeding unit, which sits on a trailer, pulled behind a “˜dozer, in the event we can’t get big trucks into an area.”

Having multiple machines not only allows Reid’s firm to do more jobs at one time, but also allows faster results on a large site. “We can get large volumes of seed and mulch on the ground in a short amount of time. With our HydroSeeders, we not only do seeding and hydromulching, but we can also spray dust-control products out of them and use them for water trucks when sites require watering.”

Large trucks carrying large loads-does altitude affect performance? “No, we’ve done work on Pike’s Peak with no problem,” says Reid. “Our guys might have problems breathing way up there, but the machines are all diesel powered, and their performance doesn’t change much. In Colorado, we’re already doing work at a higher altitude than most states, all the time.”

Some large projects cover several states, with a variety of terrain. “When we’re seeding big gas-line projects, we’ll perhaps work across several states,” Reid notes. “On flatter, more accessible areas we might straw and drill-seed, using a tractor and drill. However, the steeper areas we hydroseed.”

If the project involves post-forest-fire reclamation, the seeding is done aerially. “We pump the slurry into helicopters or aircraft, but, as we don’t own choppers, I hire a subcontractor to do this.”

Traditionally, hydroseeding slurries are tinted green, not only to blend in to the surroundings, but also so application crews can judge coverage. But Western States Reclamation sometimes must be more “artistic” with its work. “When doing projects for the US Bureau of Land Management, we use a coloring system for mulching high-visibility areas. We will tint the slurry with special colors-greens, grays, browns, black-to make it look like bushes are on the ground. It’s almost camouflage.” This is accomplished by spraying an area with one color, then remixing the slurry in the field to yield and spray another color.

Western States Reclamation has been in business since 1983, and in the dozen years Reid has been with them, he says, “they’ve always used Finn HydroSeeders. And our clients are happy. Word of mouth is how we get most of our business.”

Bonding a Bluff
Some sites just can’t be permanently conquered. “There’s a continuous landslide area in Rancho Palos Verdes,” explains Don Smith, chief operating officer of Pacific Rim Hydroseeding in Valley Center, CA. “This coastal bluff has problems with soil stability; the city knows it’s going to have to do something about it again in 2011. During October 2010, we worked on the site for the first time-and so far, so good.”

Pacific Rim crews applied a 2,500-pound-per-acre rate of wood fiber premium-quality mulch from Spokane, WA’s Fiber Marketing International. “We used Rainier Fiber,” Smith says. “The standard application rate is 2,000 pounds per acre, so we gave the site extra protection. We like FMI’s wood fiber; it’s a longer, high-quality fiber. We don’t like using paper fiber, due to the area’s soil conditions.”

The Rancho Palos Verdes site was varied. “Mainly, there was the 2:1 slope, but other parts were flat,” Smith says. “We used a native seed mix of grasses and shrubs and incorporated compost in the mix; I’ve found that increases the hydroseeding’s efficiency. Along with the higher per-acre rate, we added a Rantac guar mixture, J-3000 guar gum, at 125 pounds per acre, as a stabilizer, which creates a crust or matrix. I think it’s a superior bonder over other tackifiers, setting up a good erosion control cover.

“We’ve had good success thus far; the area experienced good rainfall in late 2010, which helped germination,” he concludes. “As for what will happen this year on this unstable bluff, only time will tell.”

Nearly the Whole Dam Area Needs Erosion Control
Folsom Dam, located about 25 miles northeast of Sacramento, CA, is undergoing renovation. The dam, which was completed in 1956, is gaining an auxiliary spillway. This Joint Federal Project, which includes the US Army Corp of Engineers, the Bureau of Reclamation, the Central Valley Flood Protection Board, and the Sacramento Area Flood Control Agency, will raise the level of flood protection for Sacramento and surrounding areas.

The project’s current phase includes a $62-million dollar contract with Martin Brothers Construction and its subcontractors. The work to be done includes two million cubic yards of spillway excavation, construction of a 7,000-cubic-yard concrete coffer dam, relocation of a 42-inch water supply pipeline that serves the city of Folsom and the nearby prison, and 100,000 cubic yards of riprap placed along the lake shore to prevent erosion. The main spillway excavation drains directly toward the American River. The close proximity of the surrounding water bodies, and approximately 80 acres of exposed soil, makes this project very sensitive to the effects of soil erosion. To meet the construction schedule and work through the winter, many types of erosion and sediment control BMPs were used to meet National Pollutant Discharge Elimination System (NPDES) requirements.

“We’ve been working for Martin Brothers, doing all their BMPs, since 2009,” says Jay Selby, president of Selby’s Soil Erosion Control in Newcastle, CA. “Our subcontractor, Decker Landscaping, is installing blankets on the spillway’s hillsides.”

Excavated material is stockpiled on the project’s east side, which is stabilized with three-step erosion control, blankets, and straw wattles before every forecasted rain event.

“We use FMI’s Rainier Fiber as the BFM,” Selby explains. “It wasn’t the originally specified BMP for these spillways, but the Army Corps of Engineers and Bureau of Reclamation have been really pleased with the FMI product’s results; it stands up to more rain. We apply it with a hydrosprayer and include it in our three-step erosion control. The first step is a hydroseed mix of virgin wood fiber, mulch, seed, and fertilizer. Next, we apply straw at the ratio of two tons per acre, then top it off with a tackifier and FMI’s Rainier Fiber wood mulch. We seed with a native mix that the Army Corps designed.”

Selby thinks the “F” in BFM can make a difference. “Fiber can be recycled newspaper; wood fiber made from recycled wood, old lumber, and recycled furniture; or virgin wood. Virgin wood holds moisture a lot better than the other two substances, and Rainier Fiber is created from virgin wood.”

With the massive amounts of materials being moved, the project’s haul road also needs maintenance. “Big rock trucks travel this road; it’s like a mining site with all the traffic. As the haul road itself gets a lot of runoff, that’s pumped to an existing advanced treatment system that uses chitosan-enhanced sand filtration. The water is then returned to Folsom Lake and the American River.”

Decker Landscaping, Selby’s “go-to” subcontractor, is securing the steep hillsides. “Decker’s placed approximately 12 acres of permanent EC blankets on surfaces that range from 1:1 to 2:1 slopes. Thirty- to 50-foot walls of rock or vertical slopes were sprayed with gunite below their area of work. Due to the terrain’s severity, Decker’s crews require fall protection, which includes full body harnesses and a rope restraining and rappelling system. Martin Brothers provided a steel safety anchoring system along the top of each slope.

“Because of the difficult working angles and the rocky subsurface, securing blankets was a challenge.” Selby continues. “Blankets were fastened with 8-inch steel nails with half-inch washers placed at 3-foot on centers. The slopes’ limited access did not allow the use of much equipment; most of the project was done by hand.

“We started work here in fall 2009; there are more phases to come. We’ve been onsite every week for the rainy season, although we put down blankets year round. The project’s current phase, completed in winter 2011, and future phases are expected to continue through 2015.” 

About the Author

Janis Keating

Janis Keating is a frequent contributor to Forester Media, Inc. publications.