As weather starts to cool in much of the country, the heat-baked cement and sweaty afternoons from this summer fade from collective memory. But activists and labor groups representing outdoor workers haven’t forgotten. They are pushing lawmakers and regulators to keep facing the heat.

Texas-based nonprofit Workers Defense Project went public Friday with the details of an unfair labor practice charge it filed with the National Labor Relations Board in February.

Oscar Torres has logged hours working at construction sites across Dallas-Fort Worth throughout the last seven years. Six times now, he hasn’t been rightfully paid, he said, losing upwards of $5,000.