Document ID: EPA-HQ-OW-2008-0667-0661
Agency: epa
Document Type: Supporting & Related Material
Title: 
Posted Date: 2011-04-20T04:00Z

MEMORANDUM

Tetra Tech, Inc.
10306 Eaton Place, Suite 340
Fairfax, VA 22030
phone	703-385-6000
fax	703-385-6007

TO:			Paul Shriner, EPA
FROM:		Blaine Snyder, Henry Latimer and Kelly Meadows
DATE: 		December 7, 2010

SUBJECT:	Estimated costs for conducting entrainment monitoring 

Introduction

Tetra Tech was tasked with developing an estimate for entrainment monitoring costs.  This memo provides multiple examples of monitoring cost estimates developed by Tetra Tech in support of 316(b) as a way to provide perspective on entrainment sampling costs and ultimately supports the use of a cost estimate of approximately $490,000 per facility per year.  This cost is reasonable on a national scale, but site-specific costs can vary significantly depending on the exact study design, the site location, the experience/expertise of the staff conducting the sampling, and other assumptions.

Examples

Example 1 

Tetra Tech (and one subcontractor) conducted entrainment sampling at "small facilities" for EPA in 2002 in support of Phase III Rule development.  We sampled at 6 facilities in the Delaware River estuary, which represents relatively local travel.  Each facility was visited twice during the peak of the spawning/nursery season.  We collected both entrainment and nearfield samples for one week (4 days) during each of the two sampling events.  Each day consisted of sampling every 3 hours over the 24-hour period.  Our total number of samples was approximately 700, and the total cost of the project was just over $600K.  Keep in mind that we're "experienced" in impingement and entrainment sampling and design (and we used an experienced subcontractor), the sampling was local, and the total costs are 2002 dollars.

Example 2

We reviewed the costs provided in the Phase II NODA (2003) and the ICR Cost Analysis and attempted to extract only entrainment sampling, laboratory, analysis, and reporting costs.  It appears that the sampling scheme proposed at the time was 3 years of sampling, 26 weeks each, with 5 samples per week, for a total of 390 entrainment samples per facility.  It is not straightforward to extract the costs from the expansive spreadsheets, but it appears that the total annual cost per facility would be approximately $100K (or $300K for 3 years of sampling).  This represents on-site entrainment sampling, using experienced personnel, and a 2003 dollar value.

Example 3 

We generated cost estimates for EPA in November 2009 based on entrainment study assumptions discussed at that time: 100 sampling events per year; sampling once per week for 10 months; sampling daily for the other 2 months; collecting 24-hour composite samples; and sampling at any/all waterbody types (excluding marine).  We added the assumptions that all samples were truly entrainment samples, collected on-site at the facility (e.g., behind the screens) and did not include any nearfield samples, boat samples, and the like.  Therefore, equipment costs (e.g., boats, nets, etc.) were not included as part of other direct costs.  Three scenarios were considered, including: a) use of a non-local consultant (i.e., requiring travel to the sampling site); b) use of a local consultant; and c) "in-house" sampling (i.e., consultants would train facility employees to do the work, resulting in labor costs that are near zero).  Consideration of the three scenarios resulted in total costs of approximately $490K, $320K, and $100K per year, respectively, in 2009 dollars. (See Attachment A.)

Discussion

As noted above, several of the cost estimates presented here were derived on a national scale using very broad assumptions and may not be representative of site-specific costs for some facilities.  Given the complexity of sampling, the lack of on-site or in-house experience, and the high level of expertise involved in conducting scientifically valid studies, we believe that most entrainment studies would be conducted by non-local consultants, resulting in the highest cost scenario presented in Example 3 above.  As a result, it is logical and appropriate to use those costs as the basis for estimating overall rule costs.

One common thread in all of these examples, despite differences in numbers of samples, locations, etc., is that the absolute minimum dollar amount needed for an entrainment sampling exercise is $100K.  However, these minimum costs can be considerably higher at some facilities due to high organism abundances, sampling access challenges, etc., and costs could easily climb to $500K, depending on the sampling scenario (even with number of samples remaining equal).  Further, costs would be expected to be higher for facilities with multiple generating units and/or cooling water intake structures.  Accordingly, it is clear that these lower estimates are not appropriate to consider in a national scale estimate; they may represent the true costs for some facilities, but are not likely to be representative of costs on a wider scale.