Abstract: At 10:45 a.m. on august 2, 2017, Employee #1 was working with a crew that was using a hydro jet system to unclog the Quick Trip sewer line. After the crew sucessfully dislodged the obstruction, the employee entered the active sewer manhole to visually inspect the condition of the line.The employee collapsed and fell to the bottom of the 7.5 foot deep manhole. The fire department responded and performed atmospheric testing and found elevated hydrogen sulfide levels at approximately 193 ppm. Employee #1 was transported by ambulance to the hospital, where he was treated and released the same day.