Christine Workman, an employee of Minteq UK (trading as Specialty Minerals), was walking in the designated pedestrian area of the site's roadway on 24 July 2017 when she was hit, Birmingham Magistrates' Court was told.
She died from her injuries on 8 August.
A Health and Safety Executive (HSE) investigation found Minteq's measures to separate vehicles and its workers on foot were inadequate.
The unprotected designated pedestrian walkway was positioned down the centre of the roadway used by workplace transport.
Minteq pleaded guilty to breaching ss 2(1) and 3(1) of the Health and Safety at Work Act. Alongside the fine of £200,000 it was ordered to pay costs of £23,218.
After the hearing HSE inspector Kay Brookes said: "Far too many people are killed and seriously injured by vehicles in the workplace every year. Provisional data for 2018-19 shows that of the 147 workers fatally injured, 30 of them were as a result of being struck by a moving vehicle. Many hundreds are left with life-changing injuries.
"The requirement to ensure adequate separation and segregation between pedestrians and vehicles is paramount. This tragic and wholly avoidable incident highlights the need for companies to comply with their legal duty to identify what can kill and seriously hurt people in their workplace and take steps to stop that happening."