The Securities and Exchange Commission has charged four individuals and two companies who persuaded more than 300 investors nationwide to participate in purported environmentally friendly investment opportunities that the SEC says were actually part of a $30 million Ponzi scheme.

The SEC alleges that Wayde and Donna McKelvy, who were previously married and living in the Denver area, targeted elderly investors or those approaching retirement age to finance the "green" initiatives of Pennsylvania-based Mantria Corp. as a supposed "carbon negative" housing community in rural Tennessee, and a "biochar" charcoal substitute made from organic waste.

The McKelvys promoted Mantria investment opportunities through their Denver-based company, Speed of Wealth LLC. The SEC alleges that with the help of two other promoters who are Mantria executives — Troy Wragg and Amanda Knorr of Philadelphia — they convinced investors attending seminars or participating in Internet "webinars" to liquidate their traditional investments, such as retirement plans and home equity, to invest instead in Mantria.

The SEC alleges that the "green" representations were laced with bogus claims, and investors were falsely promised enormous returns on their investments ranging from 17 percent to "hundreds of percent" annually. In fact, Mantria's environmental initiatives have not generated any significant cash, and any returns paid to investors have been funded almost exclusively from other investors' contributions.

"These promoters fraudulently exaggerated Mantria's green initiatives and used high-pressure tactics to convince investors to chase the promise of lucrative returns," said Don Hoerl, director of the SEC's Denver Regional Office, in a statement. "In reality, the only green these promoters seemed interested in was investors' money."

The SEC's complaint, filed in federal court in Denver, charges Mantria and Speed of Wealth, as well as the McKelvys, Wragg and Knorr, and seeks an emergency court order to freeze their assets. The SEC alleges that they overstated the scope and success of Mantria's operations in several ways to solicit investors. For instance, they claimed that Mantria was the world's leading manufacturer and distributor of biochar and had multiple facilities producing it at a rate of 25 tons per day.

In fact, Mantria has never sold any biochar and has just one facility engaged in testing biochar for possible future commercial production. Furthermore, Mantria's only source of revenue has been from its resale of vacant lots for its purported residential communities in rural Tennessee, but those did not generate cash with which to pay investor returns, because Mantria provided 100 percent financing for almost all of its vacant lot sales to buyers using other investors' funds.

The SEC charges each of the defendants with violating the antifraud and offering registration provisions of the securities laws. The SEC also charged all of the defendants except for Mantria with violating broker-dealer registration requirements. The SEC seeks injunctions, disgorgement and financial penalties from the defendants.