tar xf iscan-gt-x820-bundle-1.0.1.x64.deb.tar.gz
cd iscan-gt-x820-bundle-1.0.1.x64.deb
./install.sh

Could not send command to scanner. Check the scanner’s status.

sudo vim /etc/udev/rules.d/79-udev-epson.rules

ATTRS{manufacturer}=="EPSON", DRIVERS=="usb", SUBSYSTEMS=="usb", ATTRS{idVendor}=="04b8", ATTRS{idProduct}=="*", MODE="0777"

sudo ln -sfr /usr/lib/sane/libsane-epkowa* /usr/lib/x86_64-linux-gnu/sane

$ scanimage -L
device `epkowa:interpreter:001:010' is a Epson (unknown model) flatbed scanner

$ sane-find-scanner
could not open USB device ...
found USB scanner (vendor=0x04b8 [EPSON], product=0x013a [EPSON Scanner]) at libusb:001:010
could not open USB device ...

$ sudo sane-find-scanner
found USB scanner (vendor=0x04b8 [EPSON], product=0x013a [EPSON Scanner]) at libusb:001:010