A Chinese visitor has been fined 1,000 dollars after Yellowstone National Park officials found him walking off the designated boardwalk at the Mammoth Hot Spring thermal area and collecting thermal spring water.

The officials said on Wednesday that the visitor was breaking through the surrounding travertine crust, which is fragile limestone deposited by the springs. And because the sedimentary form of limestone formed over a long period of time and is “irreplaceable”, the tourist was heavily fined.

When interviewed, the tourists said he did not read the safety information given to him at the park’s entrance carefully. He also confessed to taking water from the spring for medical use.

The incident comes just a week after 23-year-old Colin Scott from Oregon wandered off the boardwalk at the Norris Geyser Basin and fell into a slightly acidic, 199-degree-Fahrenheit hot spring near the Porkchop Geyser. Park Rangers were not even able to recover any of his remains. A day after that, six tourists were fined 130 dollars for not walking on the established boardwalk in the park.