Arthur R. Marshall Loxahatchee National Wildlife Refuge 
10216 Lee Road, Boynton Beach, Florida 33437-4796 
Phone (561) 732-3684 Fax (561) 369-7190 
10 June 2005 
To: SFWMD and DEP 
CC: TOC members 
From: Matt Harwell 
Subject: Response to written comments on the April 19, 2005 A.R.M. Loxahatchee 
National Wildlife Refuge Enhanced Water Quality Monitoring and Modeling 
- Interim Report
On 17 May we received written comments on the April 19, 2005 A.R.M. Loxahatchee 
National Wildlife Refuge Enhanced Water Quality Monitoring and Modeling -Interim 
Report from both FDEP and SFWMD. We appreciate the time and effort put into 
providing these comments and will consider them when we produce our next annual 
report in 2006. 
The comments did reveal the need for us to reiterate the purposes of the enhanced 
monitoring program and the modeling program, and to clarify several issues: 
As stated in the report and given the relatively short period of record of report data, the 
authors do not believe that it is appropriate at this time to begin the assessment of the 
adequacy and appropriateness of the program to achieve its objectives, nor to recommend 
any adjustments to the sampling design or number and location of stations. Similarly, 
there are not enough data yet to significantly gain scientific understanding of historic and 
future exceedances. Additionally, we will focus only on better understanding of future 
exceedances if they occur, because we will have a much larger monitoring data set than 
was available for past exceedances. 
While the occurrence of canal water intrusion into the Refuge is not a new finding, we 
anticipate that our increased understanding of these events will lead to specific water 
management recommendations to minimize the degree of canal water intrusion. To 
accomplish this objective, we will focus future reports on gaining a specific 
understanding of the relationships between canal and marsh water levels and other 
factors, and their influence on the extent of intrusion. For this interim report, we logically 
focused on conductivity, which is a good indicator of the presence of canal water and its 
associated nutrients and other ions. 

We are working with USGS to make information on the Refuge’s Enhanced Water 
Quality Monitoring and Modeling Program (such as the Interim Report and the 
comments) open and available to everyone on their SOFIA web site. 
Thank you again for your comments, and we would be happy to discuss any of them 
individually with technical staff from the SFWMD or FDEP.