BANGOR, Maine — A local man seen Monday dumping bottled water he had purchased with a food stamp card in order to cash in the returnables violated federal regulations and was issued a warning by police.

The man used his Supplemental Nutrition Assistance Program benefits to purchase $15 in bottled water at Shaw’s supermarket at about 8:40 a.m. Store security personnel then saw him walk to nearby Second Street Park, police said.

“They observed him and an unknown female dump the water on the ground near a cement wall,” Bangor police Sgt. Paul Edwards said.

The 45-year-old man and his female companion then returned to the grocery store to exchange the empty bottles for cash, and police were waiting. The woman immediately left, leaving the man to answer questions.

“He basically said, ‘So what. There is nothing wrong with that,’” after explaining to police how he was using his food stamp card to get cash, Edwards said.

The man got upset when he was informed that he would not be allowed to return the bottles because he was breaking new U.S. Department of Agriculture rules on “water dumping” that went into effect in February.

The USDA runs the food stamp program and updated the definition of trafficking — a disqualifying action — to prohibit SNAP recipients from purchasing beverages just so they can dump the liquid and return the empties for cash, and the selling or trading of benefits.

“He was very mad when he left,” Edwards said.

Because the federal rules are so new, the man was not charged, the sergeant said.

“They got their names and for now, we’re going to forward them to the attorney general’s office,” Edwards said.

The man was issued a one-year criminal trespass warning for the Main Street store.

The Bangor Daily News put a spotlight on water dumping in August 2010 after a pair of men purchased $86.79 in bottled water from Shaw’s, dumped it out behind the store and returned the empties for $24.

Store employees at the time described the practice of water dumping as common, an observation shared by police.

Exactly how many SNAP recipients in Bangor have been turned away from returning bottles or cans after dumping the contents and given warnings since the new rules went into effect was not available Monday.

State prosecutors asked in January 2011 that law enforcement agencies forward water dumping reports to the welfare fraud prosecutor in the Maine attorney general’s office. Maine is one of only a dozen states that have returnables rules on the books.

A provision under the 2008 Farm Act specifically forbids the use of SNAP funds to get cash by buying products for the container’s redemption value, but until recently no penalties existed.

“The recent change of the federal definition [of SNAP trafficking] to include water dumping means the state of Maine can now begin prosecuting cases such as these, to the extent that such cases can be proven,” Kaylene Waindle, special assistant for the Maine attorney general’s office, said in February after the USDA rules were updated.

Those caught, in addition to possibly losing their SNAP benefits, could also face fraud or theft charges that carry a penalty of up to a year in jail and a fine of up to $1,000, she said.

The five or six cases of bottled water the Bangor man bought with his SNAP card on Monday would have resulted in between $6 to $7.20 back in cash, if he had been allowed to return them.

“It wasn’t much,” Edwards said.