NEIL ABERCROMBIE DIRECTOR OF HEALTH GOVERNOR OF HAWAII STATE OF HAWAI‘I In reply, please refer to: File: EHA/HEER Office DEPARTMENT OF HEALTH 2011-143-RB P.O. Box 3378 HONOLULU, HAWAI‘I 96801-3378 March 2011 To: Interested Parties From: Roger Brewer & John Peard Hazard Evaluation and Emergency Response (HEER) Subject: Technical Guidance Manual Notes: Decision Unit and Multi-Increment* Sample Investigations This technical memorandum presents a compilation of notes and recommendations for Decision Unit (DU) and Multi-Increment Sample (MIS) site investigations based on the experiences of State, Federal and private environmental professionals since publication of the HEER office Technical Guidance Manual (TGM) in 2008 and 2009. This memorandum serves as an addendum to that guidance and to Sections 3, 4 and 5 of the guidance in particular, which discuss Decision Unit designation, Multi-Increment Sample (MIS) collection and soil and sediment sample collection methods. In some cases the information provided is new but in general the memorandum simply expands on and clarifies issues already discussed in the TGM. The information presented in this memorandum will be incorporated in future updates to the TGM along with consideration of additional input from stakeholders. The HEER TGM will be continually updated as additional experience in DU-MIS investigations is gained. Comments and suggestions from the public are welcome and should be addressed to Roger Brewer (
[email protected]) or John Peard (
[email protected]) of the HEER Office. * “Multi-increment” is a registered trademark of EnviroStat, Inc. 1 Decision Unit Designation and Characterization (see TGM Section 3) • Phase I Reviews: Refer to historical Sanborn Fire insurance maps (Figure 1; produced between late 1800s to 1970s, available at UH-Manoa library among other sources), historical aerial photos (e.g., R.M.