As a new employee, IMPLEMENT STRONG BOUNDARIES. Working long field days will always lead to over 40hr work weeks. Company or client related emergencies will not compensate accordingly. 100+hr weeks will lead you to nothing more than an "exclusive company shirt" that is also not available due to low supply. Exerting extra hours when no one else is available will not gain you any position or favor. You are an employee that is used for whatever you'll give, so if possible only give that 40 hours. If you're able to gain a lead position for the relating emergency event, just know that it is only superficial and won't gain you any of the experience you need to be brought onto other client projects nor will you be compensated financially for the extra responsibilities.