How much gravel is in the gravel driveway?

A new report by the American Association of Gravel Inspectors indicates that there are millions of tons of gravel in the United States and around the world, according to a report released Tuesday.

The report comes as more states have implemented more stringent requirements to reduce pollution from the fuel used in lawns, garages and driveway grids.

It also follows the release of an earlier study that found millions of pounds of soil-based fuel, the primary fuel for the power grid, was being dumped in the country’s roads, sidewalks and highways, and that the fuel was leaching into streams and rivers.

The findings come after a series of lawsuits filed by communities in Ohio and Michigan, and a growing number of studies from around the country that have found that pollution from fuel used for lawns and parking lots is a serious problem.

The new study is the latest in a string of investigations into the problem of waste from fertilizer runoff into rivers, lakes and streams.

A 2009 EPA study found that runoff from grass-and-fertilizer lawns in Ohio contained up to 8 million pounds of ammonium nitrate, which can cause chemical reactions in plants.

The EPA said the compound has been found in streams and lakes throughout the country.

The agency said the chemical compounds can migrate into groundwater, which is considered a natural resource.

In June, EPA investigators found that fertilizer runoff from corn and soybean fields in Michigan, Indiana and Illinois was also a major source of ammonia nitrate in streams.

In Ohio, the EPA found that nearly one-third of the nation’s corn and other soybean farms contain the compound.

The Associated Press analyzed EPA data for more than 1,200 fields and found that more than 30 percent of fields in Ohio had ammonium and other fertilizer chemicals that exceeded federal guidelines.

The chemicals include: ammonium sulfate, ammonium nitrogenate, chloramphenicol, diazotene, methanol, mixtures of ammoniacal ammonium chloride and ammonium acetate, phenol, propylene glycol and propylene oxide.

In the Ohio study, the compounds were found in up to 17 percent of the ponds, lakes, rivers and streams, and in up a quarter of the corn and vegetable fields.

The chemical contaminants also were found at levels as high as 10 times the EPA limit for the chemical used to make fertilizer in some states.

In Michigan, ammonia sulfate was found in more than 90 percent of corn and about 80 percent of soybean field ponds and lakes.

In Indiana, the AP found ammonium ammonium phosphate was found at more than 6 million pounds in a large portion of corn, soybean and corn-based lawns.

The Ohio study found ammonia ammonium, nitrate and nitrogen at a level that exceeded the EPA’s limits.

EPA spokesman Tom McBride said in an email that the agency has received several requests from states to share their data on fertilizer runoff.

“The EPA is looking forward to working with state officials and others to understand the full scope of this issue,” he said.

The new EPA report found that there is no way to predict how much nitrogen is being released into streams, lakes or streams as a result of lawns being flushed with runoff.

In a statement, EPA said it was working to identify the types of nutrients released from the runoff and to identify ways to minimize the impact on water quality.

The AP said the EPA is still looking into the source of the ammonium fertilizer, but the company that made the fertilizer said in a statement that it is not a known human contaminant.

The company, Nelvana, said the fertilizer was used for irrigation in California and that it was “the most environmentally responsible fertilizer that is available in the world.”

The company said it has “zero tolerance” for any illegal activity associated with the fertilizer.

It is unclear whether the ammonia fertilizer in the Ohio report was used on lawns or lawns were planted in the pond, but both are likely the sources of the chemical pollutants, said John Lacy, an EPA scientist who has worked on the Ohio case.

A company that sells fertilizers for residential lawns also released a statement Tuesday saying that ammonium was used in some lawns on a small scale.

The statement said that ammonia was a common fertilizer used for drainage on lawn and plantings in some parts of the United Kingdom, France and Canada.