**2.3 Sampling design**

The study takes industrial and science parks having a higher water consumption as survey objects, including factories in Hsinchu Industrial Park, Chungli Industrial Park, Taichung Industrial Park, Linyuan Industrial Park, Hsinchu Science Park, Central Taiwan Science Park and Tainan Technology Industrial Park. The above industrial and science parks comprise the sampling zone of the study. For industrial parks, factories having a water consumption exceeding 200CMD are selected as survey objects, a total of 347 factories are included. Then, we call factories one by one to verify their water consumption and exclude those having a low water demand or those lacking willingness to participate our survey. After verification, a total of 205 factories are included in the survey. The survey schedule covers September and October of 2009.


Table 2. Statistics on questionnaire count of sampling zone factories

Questionnaire via fax or mail is adopted for the survey. Every returned questionnaire is checked for completion; in case of miss or obvious mistake of key items, a telephone recheck will be made against the particular factory. For factories that fail to return the questionnaire, urging telephone calls will be made. The study sends out a total of 205 questionnaires and receives 47 returns of which 2 are null; the return ratio is 22.93%. Table 3 shows questionnaire distribution of the sampling zone. For further understanding of the scenario, Table 3 is compiled to statistically manifest the WTP selected for the scenario, and the percentage of factories that are willing to use the reclaimed water at different WTPs corresponding to respective questionnaires of the study.


Note: Data of null questionnaires are not included in this table. Unit of T: NT\$/ton. Ratio of Willingness is in %.

Table 3. Return ratio of difference type of questionnaires
