var chain = new ChainLoading(),
    promises = [];

//where drop() is a function that returns a promise
promises.push(drop(usersCollection.name));
promises.push(drop(seqCollection.name));
promises.push(drop(orgsCollection.name));
promises.push(drop(networksCollection.name));

chain.pushIgnoreFail.apply(chain, promises);
chain.done(callback);