Acacia, which owns three gold-producing mines in Tanzania – Bulyanhulu, Buzwagi and North Mara - is at the heart of a sweeping crackdown on tax evasion and corruption by President John Magufuli's government.
Mwaipopo (55), who was charged with nine counts of economic sabotage at the Kisutu Resident Magistrate's Court in Dar es Salaam, is expected to be joined in a similar case involving other executives of the gold mining giant.
The prosecution of Acacia's MD comes just days after two other senior executives from the same mining company were also charged with similar charges.
Deo Mwanyika, Acacia's recently-retired vice president of corporate affairs, was charged last week alongside the company's chief advisor for government relations, Alex Lugendo, with 39 counts of tax evasion and money laundering.
Prosecutors claimed that Mwaipopo allegedly conspired with Mwanyika and Lugendo to forge various documents and evade taxes worth billions of shillings in favour of their employer, Acacia Mining, hence denying the Tanzanian government substantial revenue collection.
Several other officials of the mining firm at its North Mara Gold Mine, were also charged earlier this month at a court in Mara Region along with government land valuers and local government leaders with corruption.
The London-headquartered mining company said in a statement yesterday that Mwaipopo pleaded "not guilty to all charges" against him.
"We understand that he (Mwaipopo) has been charged with various counts of tax evasion, forgery and money laundering, but have not yet seen a copy of the charge sheet," Acacia said.
"The company notes again with concern that offences under the Tanzanian Anti-Money Laundering Act are not bailable and, accordingly, the senior manager charged today has not been released on bail."
Mwanyika and Lugendo also remain in remand prison since money laundering is not a bailable offence in Tanzania.
Acacia said yesterday that it was "deeply concerned" by the increasing risks to the safety and security of its employees in Tanzania given the criminal charges being brought by the government against some of its senior executives.
"The company believes that these recent actions represent a significant escalation of governmental pressure, as the company’s 19-month dispute with the government of Tanzania remains unresolved and as the discussions between Barrick Gold Corporation and the government have not yet been concluded," it said.
Acacia said it would continue to reach out to the government "for direct dialogue" on the ongoing tax dispute between the two sides.
The government has slapped a $190 billion tax bill on Acacia, banned exports of its gold and copper concentrates and refused to engage in direct talks with the firm, instead launching negotiations with parent company Barrick Gold.
Acacia maintained that the criminal charges filed against its Tanzanian executes relate to matters that are currently subject to international arbitration, with the majority of the charges linked to historical structuring and financing of its mines in the country.
"These contractual arbitrations have continued through 2018, with the government of Tanzania participating, including by serving its defence immediately after the filing of the criminal charges over the past two weeks," it said.
Acacia has implemented several senior management changes at its London headquarters and Dar es Salaam corporate office over the past year as its relations with the Tanzanian government soured.
The company announced in November last year that Brad Gordon, its Chief Executive Officer (CEO), and Chief Financial Officer (CFO) Andrew Wray both resigned from their positions in London.
The gold miner said at the time that Gordon was returning to his Australia home country for family reasons, while Wray was pursuing an opportunity elsewhere.
Peter Geleta, formerly Acacia’s head of organisational effectiveness, was appointed interim CEO, while Jaco Maritz, the miner's former general manager for finance, was appointed CFO effectively from January 1 this year.
The resignations came a month after Acacia's majority shareholder, Barrick Gold Corporation, agreed to cede part of the shares in Acacia’s three mines in Tanzania to the government, pay a $300 million settlement and share 50-50 "economic benefits" from its mining operations in the country with the state following talks with the government.
The top management changes in London spilled over to Tanzania when Acacia announced in February this year that for the first time, general managers of the company's mines will now be reporting to a Tanzanian Managing Director, Asa Mwaipopo.
Mwaipopo, an experienced Tanzanian mining engineer, yesterday found himself in legal trouble after being joined in the tax evasion and money laundering case.
The government approved the Mining (Integrity Pledge) Regulations in July this year, which require miners to comply with new rules effectively from this month.
Mining executives could now face severe penalties, including the possibility of spending more than 10 years in prison, under the tough new government regulations aimed at tackling tax evasion, corruption, transfer pricing and other malpractices.
"A holder of a mineral right shall not engage in any malpractices including tax evasion, double taxation, under or overpricing, transfer pricing and corruption," reads part of the new rules.
"Any person who contravenes the provisions ... commits an offence and shall be liable upon conviction, to a fine of not less than 100 million/- or to an imprisonment for a term of not less than 10 years or to both fine and imprisonment."
Transfer pricing is a method of pricing goods and services transferred within a multinational or trans-national company in order to reduce tax burdens.
The Tanzania Revenue Authority (TRA) has been struggling to tackle claims of rampant transfer pricing among some multinational companies alleged to be dodging payment of corporate tax by fraudulently inflating their operating costs, hence allowing them to declare losses.