Expe­ri­ence in the indus­tri­al exploita­tion of var­i­ous types of min­er­al deposits shows the need for their fur­ther study dur­ing the extrac­tion process. This is usu­al­ly car­ried out with­in the frame­work of oper­a­tional explo­ration. Such addi­tion­al inves­ti­ga­tion dur­ing min­ing is often rec­om­mend­ed by the State Com­mis­sion of Ukraine on Min­er­al Resources Reserves (DKZ) when review­ing detailed geo­log­i­cal and eco­nom­ic eval­u­a­tion reports of spe­cif­ic deposits and approv­ing reserves. How­ev­er, min­ing enter­pris­es them­selves are also inter­est­ed in obtain­ing addi­tion­al data about the deposit under devel­op­ment, which is nec­es­sary to ensure high extrac­tion effi­cien­cy, to plan pro­duc­tion qual­i­ty, and to max­i­mize the recov­ery of min­er­al resources from the sub­soil. In addi­tion, con­duct­ing pre­lim­i­nary explo­ration and oper­a­tional explo­ration in accor­dance with the com­pa­ny’s stan­dard is reg­u­lat­ed by clause 13.4 of order №199 dat­ed 16.12.2002 “On approval of the Instruc­tions for the appli­ca­tion of the clas­si­fi­ca­tion of min­er­al reserves and resources of the state sub­soil fund”.

Oper­a­tional explo­ration pri­mar­i­ly con­cerns deposits with com­plex geo­log­i­cal struc­tures, char­ac­ter­ized by vari­able occur­rence con­di­tions of min­er­al bod­ies, chang­ing ore para­me­ters, and unsta­ble qual­i­ty indi­ca­tors of ores. The objec­tives and meth­ods of oper­a­tional explo­ration depend on the spe­cif­ic deposit and the type of min­er­al resources. Oper­a­tional explo­ration is planned by the enter­prise in accor­dance with the require­ments of the instruc­tion and at the dis­cre­tion of the chief engi­neer and chief geol­o­gist of the enter­prise, based on geo­log­i­cal reports and the min­ing and recla­ma­tion project doc­u­men­ta­tion.

Oper­a­tional explo­ration is car­ried out to refine data about the min­ing object obtained dur­ing the stage of pre­lim­i­nary detailed explo­ration. Explo­ration work at the pro­duc­tion stage address­es the fol­low­ing tasks:

• clar­i­fi­ca­tion of data on the occur­rence con­di­tions, mor­phol­o­gy, and inter­nal struc­ture of min­er­al deposits,
• con­di­tions for the devel­op­ment of the deposit,
• assess­ment of the qual­i­ty of min­er­al raw mate­ri­als.

Explo­ration advances ahead of the active min­ing front and is car­ried out to refine the bound­aries of ore bod­ies with a high ore-bear­ing coef­fi­cient, to define the con­tours of stop­ing blocks, and to уточнити (refine) the quan­ti­ty and qual­i­ty of min­er­al reserves. The obtained data are used for pro­duc­tion design, prepa­ra­tion works, as well as annu­al and oper­a­tional plan­ning of the enter­prise.

Explo­ration con­duct­ed at the min­ing stage dif­fers from ear­li­er stages by a high­er lev­el of detail and reli­a­bil­i­ty of results. The den­si­ty of the explo­ration grid, as well as the fre­quen­cy and vol­ume of sam­pling, sig­nif­i­cant­ly increase. Inves­ti­ga­tions at the oper­a­tional explo­ration stage are car­ried out in a tar­get­ed man­ner. In this regard, oper­a­tional explo­ration solves two spe­cif­ic tasks:

• refine­ment of data from pre­vi­ous explo­ration;
• con­trol of the min­er­al extrac­tion process.

As a result of refin­ing pre­vi­ous explo­ration data, the con­tours of ore bod­ies and rock con­tacts may be adjust­ed. New infor­ma­tion may be obtained regard­ing the quan­ti­ty and com­po­si­tion of asso­ci­at­ed use­ful com­po­nents and harm­ful impu­ri­ties, the phys­i­cal and mechan­i­cal prop­er­ties of host rocks and ores, as well as the hydro­ge­o­log­i­cal con­di­tions of dif­fer­ent parts of the deposit. Accord­ing­ly, the reserves of the min­er­al resource and their dis­tri­b­u­tion by qual­i­ty grades are updat­ed.

The sec­ond task—mon­i­tor­ing the min­er­al extrac­tion process—con­sists of ensur­ing the com­plete­ness of extrac­tion and the inte­grat­ed use of min­er­al raw mate­ri­als. Dur­ing deposit devel­op­ment, the geo­log­i­cal ser­vice must address key issues such as deter­min­ing the mag­ni­tude of loss­es and the degree of dilu­tion (mix­ing with waste rock) of the extract­ed min­er­al resources. Con­tin­u­ous min­er­alog­i­cal, min­er­al-tech­no­log­i­cal, and oth­er stud­ies must also be con­duct­ed in order to achieve the most com­plete and effi­cient uti­liza­tion of the extract­ed min­er­al raw mate­ri­als. An equal­ly impor­tant func­tion of the geo­log­i­cal ser­vice at min­ing enter­pris­es is to ensure the growth of reserves and, con­se­quent­ly, the strength­en­ing of the raw mate­r­i­al base and the exten­sion of the enterprise’s oper­a­tional life­time. An increase in reserves may be achieved through the iden­ti­fi­ca­tion of new “blind” ore bod­ies or ore occur­rences dur­ing the den­si­fi­ca­tion of the explo­ration grid, as well as through the study of min­er­al­iza­tion at the flanks and deep­er hori­zons of the deposit.

Reserves refined dur­ing oper­a­tional explo­ration are updat­ed and reclas­si­fied into high­er cat­e­gories of explo­ration reli­a­bil­i­ty. Addi­tion­al­ly, reserves that have been new­ly iden­ti­fied or deplet­ed are recal­cu­lat­ed and record­ed. Con­di­tion­al­ly eco­nom­ic and sub-eco­nom­ic reserves, when brought into pro­duc­tion, are con­vert­ed into eco­nom­ic (bal­ance) reserves. Sep­a­rate­ly, exposed, pre­pared, and min­ing-ready reserves are cal­cu­lat­ed and account­ed for. Reserves locat­ed in pro­tec­tive pil­lars are also sep­a­rate­ly eval­u­at­ed, based on their indus­tri­al sig­nif­i­cance and the lev­el of geo­log­i­cal and tech­ni­cal-eco­nom­ic knowl­edge. On this basis, the deposit devel­op­ment project may be revised and adjust­ed.

As a result of refined explo­ration data, new infor­ma­tion may emerge regard­ing the geo­log­i­cal struc­ture of the deposit, the con­di­tions of ore occur­rence, and the qual­i­ty of raw mate­ri­als. This may lead to changes in the esti­mat­ed min­er­al reserves and require adjust­ments to the deposit devel­op­ment plan. The sec­ond task also involves ensur­ing the com­plete­ness of extrac­tion and the inte­grat­ed uti­liza­tion of min­er­al resources. Geo­log­i­cal ser­vices of min­ing enter­pris­es must addi­tion­al­ly ensure reserve growth, strength­en­ing of the resource base, and exten­sion of the oper­a­tional life of the enter­prise.

Oper­a­tional explo­ration is used to refine the quan­ti­ty and qual­i­ty of min­er­al reserves, clar­i­fy ore body bound­aries and pre­pared min­ing blocks, improve the effi­cien­cy and com­plete­ness of extrac­tion from the sub­soil, sup­port min­ing design and prepara­to­ry works, as well as annu­al and oper­a­tional plan­ning of enter­prise activ­i­ties.