Sadly, unless the media is present, making emotional comments to staff is almost ignored by decisionmakers who have usually made up their minds before you show up. Technical comments made to political decision makers is similarly futile. They rarely have any comfort with technical subjects - deferring any questions to their staff who almost always give an anti-public interest  political spin to their answers.

In spite of that, many decision makers actually appreciate appropriate comments - even occasionally when they completely disagree with you. 

There are several general types of effective ways to comment objecting to a project or activity. Which type of comment depends upon who your comments go to. 

First, figure out which kind of governmental body your comments go to. Here are the main possibilities.

1) Objections to the Administrative body - send Technical & Legal comments.

2) Objections or Questions on an Environmental Impact Documents. (Technical and Reasoning only)

3) Objections for an Elected Official. (Political, Emotional)

4) Appeal to a Court. (Legal, Reasoning, Political)

5) Letters to a Newspaper Editor. (All above & Emotional)
 
 

Technical comments are normally on science topics and involve established science or your personal expertise or experience and reasoning.

Example: "I live in that area and have seen the endangered birds nesting in those trees. "

It is important to write that you object to the proposed project. The simplest form of this is the "I Object" letter.
 
 

Environmental Impact comments are most effective when asking questions or providing evidence that could make a difference in the conclusions of the document.

Example: "What is the average delay at this intersection during rush hours?" or "When a road is experiencing rush hour gridlock CALTRANS standard for a Significant Impact is the addition of a single new peak hour vehicle trip."
 
 

Politicians typically do not respond to any concerns which ordinary citizens bring to them. However, if you are the only person to communicate with them about a specific project - they just might surprise you and do what you ask if your request seems reasonable and not likely to make anyone (with money) mad.

Example: "Please support funding for creating the new park."
 
 

Appeals are needed when a non-final governmental body (e.g. Planning Commission, Zoning Administrator, Architectural Review Board) approves a project and unless someone formally objects within a short deadline - the project approval is final - protected from most legal challenges.

Filing an Appeal often requires using a special form and sometimes paying a fee. Monterey County requires the public to bear the cost and effort of notifying the public so you have to address envelopes including stamps. Sometimes this involves hundreds of envelopes. 

Some Appeals are free (Appeals to the Coastal Commission) others charge thousands of dollars (Pacific Grove had a project in 2001 (the Lover's Point Towers) with an appeal fee of $15,000). In my opinion, any Appeal fee greater than the fee for filing a suit is an unconstitutional barrier preventing the public's access to courts. Further, in my experience, an agency's main reason for an Appeal fee is to discourage public participation.

An Appeal is sometimes required to get an explanation of an approval's legal inadequacy.
 
 

Courts, above all, make political decisions in environmental and public participation lawsuits - they rarely make decisions based on the law. So your "comments" (legal arguments) to the judge should be based on the most outrageous political issues, which you can solidly back up with legal reasoning and facts. 

You might keep this in mind when you are preparing comments for the Administrative record when you know the agency doesn't give a hoot about the public interest (i.e. most agencies).
 
 

Newspaper Letters can use any of many approaches. Some people believe that a personal emotional appeal is very effective. You might consider trying out a few letter approaches on friends you respect. If you have a grandmother handy - their responses can give you an excellent idea how effective your letter will be.