Early in the film, when Dr. Karen Watkins drives up to the office, her car leaves slightly whitish tire tracks. When she backs away and drives out, the tire tracks are very noticeable and dark-colored. These marks are not behind any other cars in view.
General Mark 'Stonewall' Jackson, played by Alex Cord, is wearing a Class A uniform that is noticeably lacking in any sort of identification, nor unit patches on either of the sleeves. However the biggest inaccuracy is that the character is an Army General, but his rank insignia on his epaulets are Silver Oak Leaves (which makes him a Lt. Colonel).
The hero says a certain isotope of Lithium would, in a large enough concentration at normal or near-normal temperature and pressure, blow-up in a thermonuclear (fusion) explosion. It is contrary to physics as known today for any isotope of Lithium or any other element could spontaneously form a thermonuclear explosion except under circumstances of extreme pressure and temperature such as exists in the core of a star like the Sun.
When Jake (Kevin Sorbo) demonstrates what a small amount of water will do to a small bit of lithium in a glass. He then fills the glass more than half full.
Emergency response such as that shown is the responsibility of FEMA, state emergency agencies, and/or the National Guard, not the Army.
The piece of wood which falls off the dock was obviously neither rotten nor burned to the point of weakness. To come off the dock as it did, the nails or screws had to be removed.
Supposedly the piece of wood from the dock was charred on its underside by flames from the lake; however, none of the adjacent posts showed any similar damage.
No explanation why the body found by the lake shore is bagged.
The military equipment shown is long obsolete or not used by the U.S. Army.
During the water skiing chase the wake from the camera boat is clearly visible.