0001193125-07-127144 8-K/A 2 20070531 4.01 9.01 20070531 20070531 ADA-ES INC 0001223112 2890 841457335 CO 1231 8-K/A 34 000-50216 07891717 8100 SOUTHPARK WAY B LITTLETON CO 80120 8-K/A 1 d8ka.htm FORM 8-K/A EX-16.1 2 dex161.htm LETTER FROM HEIN & ASSOCIATES, LLP