Administrator Anne M. Gorsuch reorganized the Environmental Protection Agency yesterday to split up its enforcement powers and put more policymaking authority in her own hands.

Environmentalist critics immediately charged that the move makes EPA "a toothless tiger," but EPA officials insisted there will be no reduced emphasis on enforcement of antipollution laws.

The realignment, effective July 1, will break up the Office of Enforcement, sending the pieces into six program areas: water, air, noise and radiation; solid waste and emergency responses; pesticides and toxic substances; research and development, and administration.

The change makes EPA's assistant administrators in each of those areas newly responsible for enforcing the regulations they write, and "is simply a better way of doing business," Gorsuch said. The administrators have yet to be named by President Reagan and are subject to Senate confirmation.

But the Audubon Society charged that the realignment would diffuse enforcement by putting it under politically chosen officials whose primary interests are elsewhere. The main burden of enforcing the laws will now fall on state and local governments, said Bill Butler, making the government effort "the toothless tiger it was before EPA's creation."

Marchant Wentworth of Environmental Action Inc. said the shift "creates a conflict of interest within the agency," because program managers by definition "are the good guys, trying to help the states make things work, while the enforcement people want to push the polluters into doing the right thing." Future enforcement decisions, he charged, will now be made for political reasons through politically appointed program chiefs.

EPA officials denied the charge. "This does not in any way change the relationship of EPA and the states toward enforcement," said Byron Nelson, EPA's chief press officer. Gorsuch plans to stress more cooperation with state and local governments, he said, noting that the agency's Office of Intergovernmental Relations had been renamed the Office of Intergovernmental Liaison to reflect the shift.

Gorsuch also created two associate administrators with policymaking authority under her direct control, not subject to Senate confirmation. A "legal and enforcement counsel" will make overall enforcement policy decisions and provide general legal advice, while an associate for "policy and resource management" will oversee legislative proposals, budget matters, development of regulatory standards and general policy.

The shifts juggle programs and personnel without eliminating any of them, ending weeks of rumors that whole departments were to be axed. "We moved complete functions. There's no blood on the rug," said EPA spokesman Nick deBenedictis.

Gorsuch nominated John Horton, a New Jersey businessman and engineer, to be the new assistant administrator for administration. Deputy Administrator John Hernandez, she said, would have special responsibility for overseeing EPA's scientific efforts. "Good science makes for good regulations, and good economics," Gorsuch said. "Our scientific credibility is the backbone of this agency."