Eight months after WellStar Health System paid $2.7 million to settle an improper billing case with the state, a former WellStar executive is charging that he was fired for blowing the whistle on other billing improprieties at WellStar.

Dr. Richard Lopes was fired without cause last month as president of WellStar’s medical group. He is one of four top executives that WellStar dismissed during a seven-month period — terminations that could cost the 12,000-employee health system about $5 million in severance payments.

The WellStar board of trustees abruptly terminated the system’s CEO, Dr. Gregory Simone, in September and fired its general counsel, Bonnie Wilson, the same week. WellStar declined to disclose a reason for the firings at the time.

In a letter this month to Simone, however, a WellStar lawyer says Simone was let go because he and Wilson were seen dining out together and appeared to have developed a “very close personal and professional relationship.”

In a six-page reply, Simone’s lawyer calls the claim “contrived, false and malicious.” The real reason that the board fired Simone, the attorney wrote, was to “stop the reforms instituted by Dr. Simone that they apparently found threatening to them and their friends.”

The allegations and countercharges are part of a growing pile of hostile correspondence between WellStar, its fired executives and their lawyers. The AJC was able to obtain copies of the letters because WellStar’s five hospitals are publicly owned, so some WellStar records are available for public inspection. The health system’s executives declined the newspaper’s request for interviews.

On the same day WellStar dismissed Lopes, who supervised the system’s doctors, it also terminated Chief Information Officer Ronald Strachan without cause. Susan Thompson, WellStar’s former assistant vice president for government and community affairs, resigned last month.

In its correspondence, WellStar strongly defends its personnel decisions. But the high-level purge has focused attention on WellStar, a nonprofit that runs public hospitals in Cobb, Douglas and Paulding counties.

WellStar is a major player in metro Atlanta, with nearly 300,000 emergency visits, 43,000 surgeries and more than 10,000 baby deliveries in 2010. It is governed by an 18-member board of trustees.

In a letter to interim CEO James Budzinski, Lopes accused WellStar executives of a range of improper actions. He said he was fired after a group of WellStar doctors complained about plans to centralize billing — something Lopes said was needed to halt inappropriate practices of some physicians employed by WellStar with close ties to WellStar’s leadership.

According to Lopes’ letter, a patient complaint about an inaccurate bill from a WellStar doctor prompted an internal investigation. An audit of the physician’s files uncovered a range of problems, Lopes claims in his letter, and he writes that he and other WellStar executives spoke with the doctor about the audit. WellStar fired Lopes less than three weeks later, he claims.

“I can only conclude that my termination was designed to prevent me from either reporting or making public the issues regarding the above-described billing and revenue improprieties,” Lopes said in the letter.

In its response to Lopes, an attorney representing WellStar said the firing was in no way related to the billing investigation and said WellStar’s investigation of the matter was proper and ongoing. “If it is determined that WellStar received funds to which it is not entitled, it will voluntarily disclose that fact and return the overpayment,” wrote Sharon Morgan, an attorney at an Atlanta firm that is representing WellStar.

Morgan said the system had the right to fire Lopes without cause. When he was terminated, Lopes acknowledged that WellStar “was not a good fit” for him, according to Morgan’s letter.

WellStar is rolling out its centralized scheduling and billing system for doctors, and about half of WellStar practices are now on the system, said spokesman Keith Bowermaster. Five physician practices that Lopes claimed were trying to avoid centralized billing were added to the system this month, Bowermaster said.

Bowermaster said WellStar also has a stringent program to ensure that the system handles claims properly. The WellStar claims that prompted the state investigation and $2.7 million settlement last year were unintentional and caused by a software glitch that may affect numerous hospitals, he said. “While we are not perfect, we strive for perfection, and we are committed to doing the right thing,” Bowermaster said in an e-mail to the AJC.

At the same time that Lopes lobbed his accusations, questions about the board’s firing of CEO Simone also resurfaced.

The board had refused for months to explain why it fired Simone, who has not yet been replaced.

WellStar claimed in its letter to Simone that his “special relationship” with Wilson created “an unhealthy and dysfunctional climate” for top managers and threatened WellStar’s reputation.

A six-page response from Simone’s attorney, Ben Mathis, mocked WellStar’s evidence of a “special relationship.” He was especially critical of WellStar’s reliance on two dinners in two years, including one at a restaurant where other WellStar executives also were eating together.

“It is unbelievable that a professional woman like yourself,” Mathis wrote to WellStar’s attorney, “could claim that two business dinners between senior executives somehow show ‘a special relationship.’ ”

A more questionable relationship is the one between executives and board members who benefited from Simone’s ouster, Mathis wrote. “It is this ‘special relationship’ that is behind the dismantling of the most successful executive team in the history of WellStar,” Mathis wrote.

Mathis, who is also representing Lopes and Strachan, said WellStar attacked Simone because the system is facing questions about its own actions.

“I would urge you to counsel your client that they are not some private corporation that is immune to answering to the people they serve,” Mathis wrote. “WellStar is a public institution. It is the people’s hospital for the community it serves.”

WellStar said the dismissals were not cause for concern.

“WellStar has been known for its depth in leadership,” Bowermaster said in an e-mail, “and the departure of a few individuals did not and does not have a negative impact on WellStar’s mission and vision of delivering world-class health care.”