Army Corps: 2 Asian carp DNA hits near Lake Mich.

Samples from a third round of testing in Lake Calumet are being analyzed, as the government’s Asian carp control policy requires. If they also test positive, federal officials will decide whether rapid-response measures are needed, such as a stepped-up search for actual carp using commercial netting and electric jolts to stun fish so they can be more easily landed.

Earlier this week, the Army Corps reported that nine water samples taken this spring — including seven from Lake Calumet — had tested positive. The other two were from the Chicago River.

The samples were taken above an electric barrier about 25 miles from Chicago designed to prevent aquatic species from moving between the Great Lakes and Mississippi River basins.

Federal officials contend the barrier is working well and there’s no evidence any Asian carp have passed through it. Just one live Asian carp has been found on the Lake Michigan side of the barrier.

Of nearly 5,000 water samples taken beyond the barrier, 83 have been found to contain Asian carp DNA. Critics of the government’s control strategy say those numbers suggest carp are eluding the barrier and stronger action is needed.

“I don’t think it’s smart to burn a lot of time and effort trying to determine if the fish are there,’’ said Joel Brammeier, president of the Alliance for the Great Lakes, a Chicago-based environmental group. “We already know they are there. We know the solutions we have are not sufficient.’’

Environmentalists favor placing structures in Chicago-area waterways to sever the century-old, man-made link between Lake Michigan and the Mississippi system. The Army Corps is studying that and other possible methods of preventing aquatic species from moving between the two basins, but its report is scheduled for release in 2015. Critics say that’s too slow.

Five states — Michigan, Minnesota, Ohio, Pennsylvania and Wisconsin — have filed a federal lawsuit demanding quicker action. Some scientists say if the large, voracious carp establish a foothold in the Great Lakes, they could unravel the food web by gobbling plankton needed by smaller fish that feed prized sport varieties such as walleye and trout.