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  Domtar soil conditioner - Clearing the water or muddying the question?

MOOSE CREEK -- Joseph Speck is a dairy farmer who has been farming all his life. Like many, he grows field crops: corn, soybeans, barley, hay. He works long hours and doesn't see large monetary gain.

He and his family have been working Canadian soil for 19 years since moving from Switzerland and like most who work the land, maintaining a healthy ecosystem is a high priority.

After being approached by a Domtar representative five years ago, Speck decided to become part of a pilot program to test soil conditioner on his farm. He was one of three Eastern Ontario farmers who took part in the program, and so far, he's pleased with the results.

"To me, it's really a safe thing," he said. "The pro thing for us is, because we have a sandy soil low in organic matter, you are able to add organic matter and nitrogen -- that is the main benefit to agriculture."

He's not worried about contaminants in the conditioner as he said tests are done regularly and comprehensively. And to him, it's a good example of how agriculture and industry can work "hand in hand."

"For industry, they don't need a landfill site -- and it's better environmentally to spread it our over a couple thousand acres," he said. "It helps to hold the moisture into the land.

"I think a lot of farmers will be interested in using it."

The soil conditioner, or ‘sludge,' is a byproduct of waste water treatment at Domtar Cornwall, which uses 130-million litres of water a day in their paper making process. This water undergoes a series of purification treatments before being released back to the St. Lawrence River.

Pulp fibres, clay, and lime settle out of the water during the primary stage of purification and any remaining dissolved material and unsettled particles, mostly lignin and starch, is removed using a process involving naturally occurring bacteria.

This bacteria is filtered out gradually from settling ponds and added to the settled organic material from the primary stage. The resulting mixture is a brown, crumbly material that's high in organic matter, bacteria, nitrogen, and water.

Domtar started producing the material in 1995 when waste water regulations at pulp mills became more stringent, says George Velema, Manager for Land Application and Waste Management at Domtar Cornwall.

Before then, the company was required to remove only the solid material from the water, not the lignin and starch.

Domtar now produces roughly 65,000 tonnes of pulp-sludge every year. And instead of stockpiling it, the company decided to find other uses for it, namely, using it as a soil additive.

"We have our own landfill site," Velema said. "If we were to landfill it, we would very quickly run out of room."

After obtaining Ministry of the Environment approval, Domtar started pilot projects with farms such as the Specks'. At present, they spread biosolids on 49 agricultural and sylvicultural locations in Eastern Ontario.

It's the organic matter and the bacterial content that makes the sludge a good soil additive, said Velema. "Because you're introducing bacteria, you're increasing the biological activity of the soil."

But the bacterial content of the sludge has recently come under fire from environmentalists, who claim that pathogenic (disease-producing) bacteria such as fecal streptococcus, e-coli, and fecal coliforms, are in the soil conditioner.

Dr. Fred Archibald, a microbiologist with the Pulp and Paper Institute of Canada, ran a series of tests on the sludge looking for pathogenic agents. Although fecal coliforms were detected, Archibald maintains they were not from feces.

In a letter to Michelle Landsberg, a columnist with the Toronto Star who openly criticized Domtar, the microbiologist stated that ‘fecal' coliforms include all coliforms (a type of bacteria) that grow at 44.5 C in certain lab growth media. Many coliforms that aren't from feces are also considered fecal coliforms, he wrote.

And Velema vehemently supports his findings.

"We have no human or animal contamination going in the product unless it's a bird flying overhead," he said, adding all bacteria in the conditioner are "natural and non-pathogenic."

While not being pathogenic, the bacterial content in the conditioner is the cause for another complaint of the environmentalists -- namely, the sludge's smell.

Because of the bacteria's anaerobic activity -- how they ‘breathe' in the absence of air -- sulphate molecules in the sludge are stripped of oxygen. It's the resulting release of sulfur gas that causes the odour.

"The smell is the downside," says Speck, adding it doesn't smell as bad as the area surrounding the mill in Cornwall. He said that the odour disappears soon after it is worked into the soil, which farmers are recommended to do immediately after spreading.

"If you put down manure, then it smells too," Speck points out.

Olfactory offensiveness aside, the soil conditioner has proven to be a viable additive and a worthy fertilizer, according to tests at Kemptville College.

As far as safety goes, there are strict rules in place surrounding the application of mill waste. To apply the conditioner, a farmer must first acquire a certificate of approval from the Ministry of Environment. It's because of this, says Bill Curnoe, Kemptville College director, that the product is safe.

Curnoe maintains that if the conditioner were not environmentally safe, the ministry would not approve it. And to get ministry approval, soil and sludge must be tested by reputable laboratories.

"We're pretty well versed on what's happening," Curnoe said. "As a researcher, I want to know it's not going to harm the environment and it will be of value to farmers.

"If it's not, I'd be the first to say ‘I don't want to deal with this product'."

"We're not out to harm our clients," he said in reference to the farmers who look to the college for crop advice. "That's why we got involved in these experiments."

In the last few years, Kemptville College has done a series of experiments with biosolid fertilizers and has studied its effects on hay, corn and soybean crops as well as on strawberries.

"My main sense is, it's a good product," he said, adding that like any commercial fertilizer, it must be used responsibly. "If you spread fertilizer too much, or too close to ditches, that will cause environmental problems."

However, he said that "if used at rates approved by MOE standards," it is both safe for the environment and beneficial to farmers.

"The bottom line is, if they (farmers) didn't think it's a desirable product, they're the ones who would be the first to complain."

But Domtar has received complaints, not from farmers, but notably from an environmentalist from Uxbridge.

After being approached by concerned Cornwall residents, Maureen Reilly, an independent researcher with a background in public policy, decided to look into the issue of biosolid spreading on agricultural land.

"I think farmland is at risk of being turned into waste disposal," Reilly said in an interview with the AgriNews, adding we should be very careful when introducing additives to the food chain.

"As life gets more and more toxic, I think it makes sense to protect our farmland," she said.

Continued on page 17

"You have to have a lot of respect for the fine balance of nature."

Although many tests have been done on the soil conditioner, "this stuff is far from uniform," she said, explaining that the chemical composition of mill sludge can vary from mill to mill and from time to time.

"I think there is a lot of pressure on governments from industry to assist them in efficient waste disposal methods," said Reilly, adding she believes the testing of these materials is not always done by neutral scientists, but by those with a vested interest.

This is not the case, according to John Madill, an agronomist at Kemptville College. Madill, who recently studied the effect of biosolid application on strawberries, insists the outcome of studies at the college are by no means influenced by industry.

"We are not looking for any grants (from Domtar)," he said. "Certainly, I have no connection with Domtar and neither does the college."

Madill's experiments did uncover some notable results. Both yield and size of strawberries were markedly increased with the application of soil conditioner.

However, he said the tests were done on a sandy soil low in nutrients; the difference may not have been so dramatic if the initial soil contained more organic matter, he explained.

"The results were quite phenomenal," he said. "The way that we put it on proved to be totally safe and the benefits prove to be quite outstanding."

Both the soil and the berries underwent a series of pathogenic analysis by a University of Guelph microbiologist. Nothing indicating a problem was found in these tests, he said, adding they were necessary because "one has to always be cautious."

"The actual analysis of the pathogens had no relation to industry," said Madill, adding the microbiologists were unaware of the significance of the tests.

In the 17-page Ministry of Environment and Energy guideline for the utilization of biosolids and other wastes on agricultural land, the exact criteria for obtaining a MOE certificate of approval are described.

It outlines what's required before a permit is given, as well as the testing procedures involved. It lists information such as spreading rates and amounts, the minimum distances between spreading and residences and water courses, the maximum slope of farmland, and the exact chemical contents of soil that are prerequisites to approval.

These factors are constantly and meticulously regulated, says Bill Curnoe.

"I'm not saying we should give people blanket coverage -- we have to keep an eye on what's going on -- that's why we're doing the tests."

"These companies (e.g.. Domtar) aren't fly-by-night organizations, they're in it for the long haul," Curnoe says. And to farmers like Speck, who make a living off the land, a free, high-yield fertilizer is not a bad thing.

Increased organic matter to the soil, moisture retention, nutrient content, and increased biological activity are all benefits derived from the application of soil conditioner, he said "you can't put a number on."

However, Speck does note there are some minor problems with using the soil conditioner. Because the time between ordering the sludge and spreading can take a few days, he said, it is not always convenient.

"You have to watch the condition of the soil when you spread," he said, explaining there is a possibility the spreading trucks will compact the soil.

And with Domtar planning on charging for the conditioner in the future, he is not sure how economical it would be if he had to pay for it. If prices were similar to commercial fertilizer, which, if he wanted, he could get the same day it was ordered, he would have some thinking to do.

But he does maintain soil conditioner, while not so necessary for soils high in organic matter, does provide a greater long term benefit for soils than commercial fertilizers.

Part of the reason Domtar is planning to charge for the material is to offset the cost of distributing and spreading the conditioner, says Velema.

Cheaper than building additional landfill sites, the cost of the land application program puts more money into rural communities, he said.

Domtar's soil conditioner is currently under review by Agriculture and Agrifood Canada. If and when the product is certified, Domtar plans to charge 50 cents a tonne plus one cent per kilometre per tonne delivered, he said.

"We feel it's worth about $2 a tonne for only its fertilizer value, not including the organic matter," he said, adding the company has supporting research to back up these estimates.

As for soil compaction, Velema said Domtar does everything the company can to minimize damaging soil. "Special equipment," with low pressure balloon tires, driven only when the soil is not saturated with water, reduces the chance of soil compaction, he said.

"We use the best equipment and take our time," he said.

When it comes to defending the soil conditioner, Velema believes Domtar is doing the right thing. He said that before, when the secondary water treatment wasn't required, a lot of the material went directly into the river.

"It makes sense to use it rather than throw it away," he said, adding that most, if not all Canadian pulp and paper mills are implementing similar programs since provincial and federal regulations called for reduced Biological Oxygen Demand, (BOD) in out-going mill effluent.

This refers to the amount of oxygen required by bacteria to decompose organic matter in the water. If BOD is too high, naturally occurring bacteria in the rivers will use up a disproportionate amount of oxygen dissolved in the water -- oxygen that is necessary for the health of fish.

Velema says Domtar's water treatment removes 98-99 per cent of BOD, surpassing current ministry standards. He says the bacteria Domtar uses in secondary treatment are similar to those found in the ecosystem, but now "the natural processes happen in controlled conditions rather than in the river," he said.

He says that the chemical composition of mill sludge can vary between mills, mainly because of varying treatment processes, including the amounts and kinds of bacteria used, and the amounts of chemicals added. But he stressed that Domtar's final product is kept uniform through a strict and thorough set of controls, he said.

"We have a living biological system that doesn't appreciate upsets," he said, adding the end result is always uniform due to the constant conditions in the secondary treatment.

He likens the bacteria to a working team of ‘bugs,' and if the bugs aren't kept happy, they don't do their job right, and they'll rebel.

It's a "natural fail-safe system," he said, comparing it to a canary in a coal-mine. "If the canary keels over, you know the air is not so good."



Eastern Ontario AgriNews is published on the third Monday of each month. The printed version is distributed free by postal mail to farms in Eastern Ontario, Canada.

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